diff --git a/hw1/claudio_maggioni/README.txt b/hw1/claudio_maggioni/README.txt new file mode 100644 index 0000000..a4211f8 --- /dev/null +++ b/hw1/claudio_maggioni/README.txt @@ -0,0 +1,4 @@ +Implemented bonuses: +- Gallery +- one column mobile form layout + diff --git a/hw2/claudio_maggioni/jsverify-util.js b/hw2/claudio_maggioni/jsverify-util.js new file mode 100644 index 0000000..3278470 --- /dev/null +++ b/hw2/claudio_maggioni/jsverify-util.js @@ -0,0 +1,226 @@ +function jsc_utils(jsc) { + function copyArgs(f) { + function f_(...args) { + let copies = args.map(a => { + if (typeof a === "function") return a; + else return _.cloneDeep(a); + }); + return f.apply(this, copies); + }; + return f_; + } + + // patch the function to use copied arbitrary values + // jsverify goes crazy if arbitrary arguments are mutated + function patchArgs(args) { + let args_ = _.initial(args); + let f = _.last(args); + args_.push(copyArgs(f)); + return args_; + } + + function mocha_property(name, ...args) { + let args_ = patchArgs(args); + args_.unshift(name); + return jsc.property.apply(this, args_); + } + + function pretty_function(data) { + function display(pair) { + let [as, r] = pair; + if (!_.isArray(as)) as = [as]; + return '\t\tcase ' + JSON.stringify(as) + ': return ' + + JSON.stringify(r) + ';'; + } + return 'function(...args) {\n\tswitch(args) {\n' + data.map(display).join('\n') + '}\n}'; + } + function pretty(v) { + if (typeof v === 'function') { + if (v.original_fun !== undefined) v = v.original_fun; + return pretty_function(v.internalMap.data); + return JSON.stringify(v.internalMap.data, undefined, 2); + } + return JSON.stringify(v, undefined, 2); + } + + function qunit_property_result(name, ...args) { + let args_ = patchArgs(args); + let res = jsc.check(jsc.forall.apply(this, args_)); + if (res == true) + return QUnit.assert.pushResult({result: true, message: name}); + let ce = '(' + _.take(res.counterexample, args.length - 1).map(pretty).join(',\n ') + ')\n'; + return QUnit.assert.pushResult( + {result: false, + actual: res.exc.actual, + expected: res.exc.expected, + message: name + ' failed after ' + + res.tests + ' tests, counterexample:\n' + ce, + expectedLog: res.exc.expectedLog, + resultLog: res.exc.resultLog, + outputLog: res.exc.outputLog}); + } + + function qunit_property(name, ...args) { + let args_ = patchArgs(args); + return ok(jsc.assert(jsc.forall.apply(this,args_)) || true, name); + } + + function propEqual(x,y,rl,el,ol) { + if (_.isEqual(x,y)) return true; + throw { actual: x, expected: y, expectedLog: el, resultLog: rl, outputLog: ol}; + } + + return { + mocha_property: mocha_property, + qunit_property: qunit_property, + qunit_property_result: qunit_property_result, + propEqual: propEqual + }; +} + +function arbitrary_utils(jsc) { + /* custom arbitraries */ + function set(arb) { + return arb.smap(_.uniq, _.identity); + } + + function oneOfWeight(...args) { + return jsc.oneof(_.flatMap(args, x => _.fill(Array(x[1]), x[0]))); + } + + function equalLengthArrays(...args) { + // generate an array of tuples + let arbA = jsc.array(jsc.tuple(args)); + return arbA.smap( + x => { + if (x.length == 0) return _.map(args, x => []); + return _.unzip(x); + }, + y => _.zip.apply(null, y) + ); + } + + function sortedArray(t) { + return jsc.array(t).smap(_.sortBy,_.identity); + } + + function vect(t, n) { + return jsc.tuple(_.fill(Array(n), t)); + } + + function roseTree(t, max_level) { + if (max_level <= 0) return jsc.array(t); + return jsc.array(jsc.oneof(t, roseTree(t, max_level - 1))); + } + + function charRange(min,max) { + return jsc.nonshrink(jsc.integer(min.charCodeAt(0), max.charCodeAt(0)).smap( + String.fromCharCode, + c => c.charCodeAt(0))); + } + + let lLetter = charRange('a', 'z'); + let uLetter = charRange('A', 'Z'); + let letter = jsc.oneof(lLetter, uLetter); + + let whitespace = oneOfWeight([jsc.constant(' '), 5], + [jsc.constant(' '), 4], + [jsc.constant(' '), 1], + [jsc.constant('\t'), 1]); + + let punctuation = oneOfWeight([jsc.constant('.'), 3], + [jsc.constant('...'),1], + [jsc.constant('!'), 1], + [jsc.constant('?'), 1]); + + function permutation(n) { + return jsc.tuple(_.times(n-1, i => jsc.nat(n-i-1))); + } + + function some(arb,min,max) { + return jsc.bless({ + generator: jsc.integer(min,max).generator + .flatmap(n => vect(arb,n).generator) + }); + } + + function word(l,min,max) { + return some(l,min,max).smap(a => a.join(''), s => s.split('')); + } + + function sentence(w,wSp,initWSp,trailWSp,p,min,max) { + return jsc.bless({ + generator: jsc.integer(min,max).generator.flatmap( + n => jsc.generator.tuple([vect(w,n).generator, + vect(wSp, n-1).generator, + initWSp.generator, + trailWSp.generator, + p.generator]).map(a => { + let [ws,wSps,iWs,tWs,p] = a; + wSps.push(p + tWs); + return iWs + + _.zipWith(ws, wSps, _.add).join(''); + })) + }); + } + + let posInteger = jsc.nat.smap(x => x+1, x => x-1); + + // jsverify doesn't have arbitrary multi-argument functions + // but it has curried functions and functions accepting tuples + // to get usual multi-argument functions we can either uncurry + // the generated function (in case we choose to generated + // curried function) or grab all functions arguments as an + // array and pass it to the generated function accepting tuples. + // Here we choose to use tuple-based version to get better counterexamples. + // There is a small catch: we have to ensure the right length of the tuple, + // otherwise f(1,2,ununsed_arg) won't be the same as f(1,2). + function fixManyArgFun(n,f) { + let fixed_f = function(...args) { + let as = _.take(args,n); + let d = n - as.length; + if (d) as.concat(_.fill(Array(d), undefined)); + return f(as); + }; + fixed_f.original_fun = f; + return fixed_f; + } + + // arbitrary function taking n arguments + function fnN(n, returnArb) { + let funArb = jsc.fn(returnArb); + let oldShow = funArb.show; + return funArb.smap(f => fixManyArgFun(n,f), + f => f.original_fun, + f => oldShow(f.original_fun)); + } + + function fn2(returnArb) { return fnN(2, returnArb); } + function fn3(returnArb) { return fnN(3, returnArb); } + + let anything = jsc.oneof(jsc.json, jsc.fn(jsc.json), jsc.falsy); + + return { + set: set, + oneOfWeight: oneOfWeight, + vect: vect, + equalLengthArrays: equalLengthArrays, + sortedArray: sortedArray, + roseTree: roseTree, + charRange: charRange, + permutation: permutation, + uLetter: uLetter, + lLetter: lLetter, + letter: letter, + whitespace: whitespace, + punctuation: punctuation, + some: some, + word: word, + sentence: sentence, + posInteger: posInteger, + fnN : fnN, + fn2 : fn2, + fn3 : fn3, + anything + }; +} diff --git a/hw2/claudio_maggioni/qunit-compat.js b/hw2/claudio_maggioni/qunit-compat.js new file mode 100644 index 0000000..dec4568 --- /dev/null +++ b/hw2/claudio_maggioni/qunit-compat.js @@ -0,0 +1,5 @@ +let test = QUnit.test; +let equal = QUnit.assert.equal.bind(QUnit.assert); +let notEqual = QUnit.assert.notEqual.bind(QUnit.assert); +let deepEqual = QUnit.assert.deepEqual.bind(QUnit.assert); +let notDeepEqual = QUnit.assert.notDeepEqual.bind(QUnit.assert); diff --git a/hw2/claudio_maggioni/resources/jsverify.standalone.js b/hw2/claudio_maggioni/resources/jsverify.standalone.js new file mode 100644 index 0000000..800d0af --- /dev/null +++ b/hw2/claudio_maggioni/resources/jsverify.standalone.js @@ -0,0 +1,5588 @@ +(function(f){if(typeof exports==="object"&&typeof module!=="undefined"){module.exports=f()}else if(typeof define==="function"&&define.amd){define([],f)}else{var g;if(typeof window!=="undefined"){g=window}else if(typeof global!=="undefined"){g=global}else if(typeof self!=="undefined"){g=self}else{g=this}g.jsc = f()}})(function(){var define,module,exports;return (function e(t,n,r){function s(o,u){if(!n[o]){if(!t[o]){var a=typeof require=="function"&&require;if(!u&&a)return a(o,!0);if(i)return i(o,!0);var f=new Error("Cannot find module '"+o+"'");throw f.code="MODULE_NOT_FOUND",f}var l=n[o]={exports:{}};t[o][0].call(l.exports,function(e){var n=t[o][1][e];return s(n?n:e)},l,l.exports,e,t,n,r)}return n[o].exports}var i=typeof require=="function"&&require;for(var o=0;o (arbitrary a | arbitrary b | ...)) + -> { key: arbitrary a, key: arbitrary b, ... }): + { key: arbitrary a, key: arbitrary b, ... } + ``` + + Mutually recursive definitions. Every reference to a sibling arbitrary + should go through the `tie` function. + + ```js + { arb1, arb2 } = jsc.letrec(function (tie) { + return { + arb1: jsc.tuple(jsc.int, jsc.oneof(jsc.const(null), tie("arb2"))), + arb2: jsc.tuple(jsc.bool, jsc.oneof(jsc.const(null), tie("arb1"))), + } + }); + ``` +*/ +function letrec(definition) { + // We must use a lazy dictionary because we do not know the key set + // before calling the definition. + var lazyArbs = {}; + + function tie(name) { + if (!lazyArbs.hasOwnProperty(name)) { + lazyArbs[name] = lazyArbitrary(); + } + return lazyArbs[name]; + } + + var strictArbs = definition(tie); + + Object.keys(lazyArbs).forEach(function (key) { + var strictArb = strictArbs[key]; + if (!strictArb) { + throw new Error("undefined lazy arbitrary: " + key); + } + lazyArbs[key].strict = strictArb; + }); + + return strictArbs; +} + +function recursive(arbZ, arbS) { + var genZ = arbZ.generator; + var genS = function (recGen) { + var recArb = arbitraryBless({ + generator: recGen, + shrink: shrink.noop, + show: show.def, + }); + return arbS(recArb).generator; + }; + + var gen = generator.recursive(genZ, genS); + return arbitraryBless({ + generator: gen, + shrink: shrink.noop, + show: show.def, + }); +} + +module.exports = { + nonshrink: nonshrink, + pair: pairArb, + either: either, + unit: unit, + dict: dictArb, + json: jsonArb, + nearray: nearrayArb, + array: arrayArb, + tuple: tuple, + sum: sum, + oneof: oneof, + recursive: recursive, + letrec: letrec, +}; + +},{"./arbitraryAssert.js":3,"./arbitraryBless.js":4,"./array.js":5,"./dict.js":7,"./generator.js":13,"./json.js":14,"./pair.js":16,"./show.js":21,"./shrink.js":22,"./utils.js":28,"assert":29}],3:[function(require,module,exports){ +"use strict"; + +var assert = require("assert"); + +function arbitraryAssert(arb) { + assert(arb !== undefined && arb !== null && typeof arb === "object", "arb should be an object"); + assert(typeof arb.generator === "function" && typeof arb.generator.map === "function", + "arb.generator should be a function"); + assert(typeof arb.shrink === "function" && typeof arb.shrink.smap === "function", + "arb.shrink should be a function"); + assert(typeof arb.show === "function", "arb.show should be a function"); + assert(typeof arb.smap === "function", "arb.smap should be a function"); +} + +module.exports = arbitraryAssert; + +},{"assert":29}],4:[function(require,module,exports){ +"use strict"; + +var show = require("./show.js"); + +/** + ### Arbitrary data +*/ + +// Blessing: i.e adding prototype +/* eslint-disable no-use-before-define */ +function arbitraryProtoSMap(f, g, newShow) { + /* jshint validthis:true */ + var arb = this; // eslint-disable-line no-invalid-this + return arbitraryBless({ + generator: arb.generator.map(f), + shrink: arb.shrink.smap(f, g), + show: newShow || show.def, + }); +} +/* eslint-enable no-use-before-define */ + +/** + - `.smap(f: a -> b, g: b -> a, newShow: (b -> string)?): arbitrary b` + + Transform `arbitrary a` into `arbitrary b`. For example: + + `g` should be a [right inverse](http://en.wikipedia.org/wiki/Surjective_function#Surjections_as_right_invertible_functions) of `f`, but doesn't need to be complete inverse. + i.e. i.e. `f` doesn't need to be invertible, only surjective. + + ```js + var positiveIntegersArb = nat.smap( + function (x) { return x + 1; }, + function (x) { return x - 1; }); + ``` + + ```js + var setNatArb = jsc.array(jsc.nat).smap(_.uniq, _.identity); + ``` + + Right inverse means that *f(g(y)) = y* for all *y* in *Y*. Here *Y* is a type of **arrays of unique natural numbers**. For them + ```js + _.uniq(_.identity(y)) = _.uniq(y) = y + ``` + + Opposite: *g(f(x))* for all *x* in *X*, doesn't need to hold. *X* is **arrays of natural numbers**: + ```js + _.identity(_uniq([0, 0])) = [0]] != [0, 0] + ``` + + We need an inverse for shrinking, and there right inverse is enough. We can always *pull back* `smap`ped value, shrink the preimage, and *map* or *push forward* shrunken preimages again. +*/ +function arbitraryBless(arb) { + arb.smap = arbitraryProtoSMap; + return arb; +} + +module.exports = arbitraryBless; + +},{"./show.js":21}],5:[function(require,module,exports){ +"use strict"; + +var arbitraryAssert = require("./arbitraryAssert.js"); +var arbitraryBless = require("./arbitraryBless.js"); +var generator = require("./generator.js"); +var show = require("./show.js"); +var shrink = require("./shrink.js"); +var utils = require("./utils.js"); + +function makeArray(flavour) { + return function arrayImpl(arb) { + arb = utils.force(arb); + + arbitraryAssert(arb); + + return arbitraryBless({ + generator: generator[flavour](arb.generator), + shrink: shrink[flavour](arb.shrink), + show: show.array(arb.show), + }); + }; +} + +var array = makeArray("array"); +var nearray = makeArray("nearray"); + +module.exports = { + array: array, + nearray: nearray, +}; + +},{"./arbitraryAssert.js":3,"./arbitraryBless.js":4,"./generator.js":13,"./show.js":21,"./shrink.js":22,"./utils.js":28}],6:[function(require,module,exports){ +"use strict"; + +var assert = require("assert"); + +var arbitraryBless = require("./arbitraryBless.js"); +var generator = require("./generator.js"); +var show = require("./show.js"); +var shrink = require("./shrink.js"); + +/** + - `bless(arb: {...}): arbitrary a` + + Bless almost arbitrary structure to be proper arbitrary. *Note*: this function mutates argument. + + #### Example: + + ```js + var arbTokens = jsc.bless({ + generator: function () { + switch (jsc.random(0, 2)) { + case 0: return "foo"; + case 1: return "bar"; + case 2: return "quux"; + } + } + }); + ``` +*/ +function bless(arb) { + assert(arb !== null && typeof arb === "object", "bless: arb should be an object"); + assert(typeof arb.generator === "function", "bless: arb.generator should be a function"); + + // default shrink + if (typeof arb.shrink !== "function") { + arb.shrink = shrink.noop; + } + + // default show + if (typeof arb.show !== "function") { + arb.show = show.def; + } + + generator.bless(arb.generator); + shrink.bless(arb.shrink); + + arbitraryBless(arb); + return arb; +} + +module.exports = bless; + +},{"./arbitraryBless.js":4,"./generator.js":13,"./show.js":21,"./shrink.js":22,"assert":29}],7:[function(require,module,exports){ +/* @flow weak */ +"use strict"; + +var arbitraryAssert = require("./arbitraryAssert.js"); +var array = require("./array.js"); +var generator = require("./generator.js"); +var pair = require("./pair.js"); +var string = require("./string.js"); +var utils = require("./utils.js"); + +function makeMapShow(elShow) { + return function (m) { + return "{" + Object.keys(m).map(function (k) { + return k + ": " + elShow(m[k]); + }).join(", ") + "}"; + }; +} + +/** + - `dict.generator(gen: generator a): generator (dict a)` +*/ +function generateDict(gen) { + var pairGen = generator.pair(string.string.generator, gen); + var arrayGen = generator.array(pairGen); + var result = arrayGen.map(utils.pairArrayToDict); + + return utils.curried2(result, arguments); +} + +function dict(arb) { + arb = utils.force(arb); + arbitraryAssert(arb); + + var pairArbitrary = pair.pair(string.string, arb); + var arrayArbitrary = array.array(pairArbitrary); + + return arrayArbitrary.smap(utils.pairArrayToDict, utils.dictToPairArray, makeMapShow(arb.show)); +} + +module.exports = { + arbitrary: dict, + generator: generateDict, +}; + +},{"./arbitraryAssert.js":3,"./array.js":5,"./generator.js":13,"./pair.js":16,"./string.js":24,"./utils.js":28}],8:[function(require,module,exports){ +"use strict"; + +var assert = require("assert"); + +/** + ### either +*/ + +function Left(value) { + this.value = value; +} + +function Right(value) { + this.value = value; +} + +/** + - `either.left(value: a): either a b` +*/ +function left(value) { + return new Left(value); +} + +/** + - `either.right(value: b): either a b` +*/ +function right(value) { + return new Right(value); +} + +/** + - `either.either(l: a -> x, r: b -> x): x` +*/ +Left.prototype.either = function lefteither(l) { + return l(this.value); +}; + +Right.prototype.either = function righteither(l, r) { + return r(this.value); +}; + +/** + - `either.isEqual(other: either a b): bool` + + TODO: add `eq` optional parameter +*/ +Left.prototype.isEqual = function leftIsEqual(other) { + assert(other instanceof Left || other instanceof Right, "isEqual: `other` parameter should be either"); + return other instanceof Left && this.value === other.value; +}; + +Right.prototype.isEqual = function rightIsEqual(other) { + assert(other instanceof Left || other instanceof Right, "isEqual: `other` parameter should be either"); + return other instanceof Right && this.value === other.value; +}; + +/** + - `either.bimap(f: a -> c, g: b -> d): either c d` + + ```js + either.bimap(compose(f, g), compose(h, i)) ≡ either.bimap(g, i).bimap(f, h); + ``` + +*/ +Left.prototype.bimap = function leftBimap(f) { + return new Left(f(this.value)); +}; + +Right.prototype.bimap = function rightBimap(f, g) { + return new Right(g(this.value)); +}; + +/** + - `either.first(f: a -> c): either c b` + + ```js + either.first(f) ≡ either.bimap(f, utils.identity) + ``` +*/ +Left.prototype.first = function leftFirst(f) { + return new Left(f(this.value)); +}; + +Right.prototype.first = function rightFirst() { + return this; +}; + +/** + - `either.second(g: b -> d): either a d` + + ```js + either.second(g) === either.bimap(utils.identity, g) + ``` +*/ +Left.prototype.second = function leftSecond() { + return this; +}; + +Right.prototype.second = function rightSecond(g) { + return new Right(g(this.value)); +}; + +module.exports = { + left: left, + right: right, +}; + +},{"assert":29}],9:[function(require,module,exports){ +/* @flow weak */ +"use strict"; + +var arbitrary = require("./arbitrary.js"); +var fn = require("./fn.js"); +var primitive = require("./primitive.js"); +var small = require("./small.js"); +var string = require("./string.js"); +var utils = require("./utils.js"); + +var environment = utils.merge(primitive, string, { + pair: arbitrary.pair, + unit: arbitrary.unit, + either: arbitrary.either, + dict: arbitrary.dict, + array: arbitrary.array, + nearray: arbitrary.nearray, + json: arbitrary.json, + fn: fn.fn, + fun: fn.fn, + nonshrink: arbitrary.nonshrink, + small: small.arbitrary, +}); + +module.exports = environment; + +},{"./arbitrary.js":2,"./fn.js":11,"./primitive.js":17,"./small.js":23,"./string.js":24,"./utils.js":28}],10:[function(require,module,exports){ +/* @flow weak */ +"use strict"; + +var utils = require("./utils.js"); + +/* + #### FMap (eq : a -> a -> bool) : FMap a + + Finite map, with any object a key. + + Short summary of member functions: + + - FMap.insert (key : a) (value : any) : void + - FMap.get (key : a) : any + - FMap.contains (key : a) : obool +*/ +function FMap(eq) { + this.eq = eq || utils.isEqual; + this.data = []; +} + +FMap.prototype.contains = function FMapContains(key) { + for (var i = 0; i < this.data.length; i++) { + if (this.eq(this.data[i][0], key)) { + return true; + } + } + + return false; +}; + +FMap.prototype.insert = function FMapInsert(key, value) { + for (var i = 0; i < this.data.length; i++) { + if (this.eq(this.data[i][0], key)) { + this.data[i] = [key, value]; + return; + } + } + + this.data.push([key, value]); +}; + +FMap.prototype.get = function FMapGet(key) { // eslint-disable-line consistent-return + for (var i = 0; i < this.data.length; i++) { + if (this.eq(this.data[i][0], key)) { + return this.data[i][1]; + } + } +}; + +module.exports = FMap; + +},{"./utils.js":28}],11:[function(require,module,exports){ +/* @flow weak */ +"use strict"; + +var arbitraryBless = require("./arbitraryBless.js"); +var generator = require("./generator.js"); +var FMap = require("./finitemap.js"); +var json = require("./json.js"); +var shrink = require("./shrink.js"); +var utils = require("./utils.js"); + +/** + ### Arbitrary functions + + - `fn(arb: arbitrary a): arbitrary (b -> a)` + - `fun(arb: arbitrary a): arbitrary (b -> a)` +*/ + +function fn(arb) { + arb = utils.force(arb || json.json); + + return arbitraryBless({ + generator: generator.bless(function (size) { + var m = new FMap(); + + var f = function (arg) { + if (!m.contains(arg)) { + var value = arb.generator(size); + m.insert(arg, value); + } + + return m.get(arg); + }; + + f.internalMap = m; + return f; + }), + + shrink: shrink.noop, + show: function (f) { + return "[" + f.internalMap.data.map(function (item) { + return "" + item[0] + ": " + arb.show(item[1]); + }).join(", ") + "]"; + }, + }); +} + +module.exports = { + fn: fn, + fun: fn, +}; + +},{"./arbitraryBless.js":4,"./finitemap.js":10,"./generator.js":13,"./json.js":14,"./shrink.js":22,"./utils.js":28}],12:[function(require,module,exports){ +/* @flow weak */ +"use strict"; + +var trampa = require("trampa"); + +/** + #### isPromise p : bool + + Optimistic duck-type check for promises. + Returns `true` if p is an object with `.then` function property. +*/ +function isPromise(p) { + /* eslint-disable no-new-object */ + return new Object(p) === p && typeof p.then === "function"; + /* eslint-enable non-new-object */ +} + +/** + #### map (Functor f) => (p : f a) (g : a -> b) : f b + + This is functor map, known as `map` or `fmap`. + Essentially `f(p)`. If `p` is promise, returns new promise. + Using `map` makes code look very much [CPS-style](http://en.wikipedia.org/wiki/Continuation-passing_style). +*/ +function map(p, g) { + if (isPromise(p)) { + return p.then(function (x) { + return map(x, g); + }); + } else if (trampa.isTrampoline(p)) { + return p.jump(function (x) { + return map(x, g); + }); + } else { + return g(p); + } +} + +/** + #### bind (Functor f) => (k : a -> f b) (xs : a) (h : b -> f c) -> f c + + This is almost monadic bind. +*/ +function bind(f, xs, h) { + var r; + var exc; + try { + r = f.apply(undefined, xs); + } catch (e) { + r = false; + exc = e; + } + + if (isPromise(r)) { + return r.then( + h, + function (e) { + // exc is always unset here + return h(false, e); + } + ); + } else { + return h(r, exc); + } +} + +// recursively unwrap trampoline and promises +function run(x) { + if (isPromise(x)) { + return x.then(run); + } else if (trampa.isTrampoline(x)) { + return run(x.run()); + } else { + return x; + } +} + +function pure(x) { + if (isPromise(x)) { + return x; + } else { + return trampa.wrap(x); + } +} + +module.exports = { + isPromise: isPromise, + map: map, + pure: pure, + bind: bind, + run: run, +}; + +},{"trampa":32}],13:[function(require,module,exports){ +/* @flow weak */ +"use strict"; + +var assert = require("assert"); +var either = require("./either.js"); +var random = require("./random.js"); +var sum = require("./sum.js"); +var utils = require("./utils.js"); + +/** + ### Generator functions + + A generator function, `generator a`, is a function `(size: nat) -> a`, which generates a value of given size. + + Generator combinators are auto-curried: + + ```js + var xs = jsc.generator.array(jsc.nat.generator, 1); // ≡ + var ys = jsc.generator.array(jsc.nat.generator)(1); + ``` + + In purely functional approach `generator a` would be explicitly stateful computation: + `(size: nat, rng: randomstate) -> (a, randomstate)`. + *JSVerify* uses an implicit random number generator state, + but the value generation is deterministic (tests are reproducible), + if the primitives from *random* module are used. +*/ + +// Blessing: i.e adding prototype +/* eslint-disable no-use-before-define */ +function generatorProtoMap(f) { + /* jshint validthis:true */ + var generator = this; // eslint-disable-line no-invalid-this + generatorAssert(generator); + return generatorBless(function (size) { + return f(generator(size)); + }); +} + +function generatorProtoFlatMap(f) { + /* jshint validthis:true */ + var generator = this; // eslint-disable-line no-invalid-this + generatorAssert(generator); + return generatorBless(function (size) { + return f(generator(size))(size); + }); +} +/* eslint-enable no-use-before-define */ + +function generatorAssert(generator) { + assert(typeof generator === "function", "generator should be a function"); + assert(generator.map === generatorProtoMap, "generator.map should be a function"); + assert(generator.flatmap === generatorProtoFlatMap, "generator.flatmap should be a function"); + assert(generator.flatMap === generatorProtoFlatMap, "generator.flatMap should be a function"); +} + +/** + - `generator.bless(f: nat -> a): generator a` + + Bless function with `.map` and `.flatmap` properties. + + - `.map(f: a -> b): generator b` + + Map `generator a` into `generator b`. For example: + + ```js + positiveIntegersGenerator = nat.generator.map( + function (x) { return x + 1; }); + ``` + + - `.flatmap(f: a -> generator b): generator b` + + Monadic bind for generators. Also `flatMap` version is supported. +*/ +function generatorBless(generator) { + generator.map = generatorProtoMap; + generator.flatmap = generatorProtoFlatMap; + generator.flatMap = generatorProtoFlatMap; + return generator; +} + +/** + - `generator.constant(x: a): generator a` +*/ +function generateConstant(x) { + return generatorBless(function () { + return x; + }); +} + +/** + - `generator.combine(gen: generator a..., f: a... -> b): generator b` +*/ +function generatorCombine() { + var generators = Array.prototype.slice.call(arguments, 0, -1); + var f = arguments[arguments.length - 1]; + + return generatorBless(function (size) { + var values = generators.map(function (gen) { + return gen(size); + }); + + return f.apply(undefined, values); + }); +} + +/** + - `generator.oneof(gens: list (generator a)): generator a` +*/ +function generateOneof(generators) { + // TODO: generator + generators.forEach(function (gen) { + assert(typeof gen === "function"); + }); + + var result = generatorBless(function (size) { + var idx = random(0, generators.length - 1); + var gen = generators[idx]; + return gen(size); + }); + + return utils.curried2(result, arguments); +} + +// Helper, essentially: log2(size + 1) +function logsize(size) { + return Math.max(Math.round(Math.log(size + 1) / Math.log(2), 0)); +} + +/** + - `generator.recursive(genZ: generator a, genS: generator a -> generator a): generator a` +*/ +function generatorRecursive(genZ, genS) { + return generatorBless(function (size) { + function rec(n, sizep) { + if (n <= 0 || random(0, 3) === 0) { + return genZ(sizep); + } else { + return genS(generatorBless(function (sizeq) { + return rec(n - 1, sizeq); + }))(sizep); + } + } + + return rec(logsize(size), size); + }); +} + +/** + - `generator.pair(genA: generator a, genB: generator b): generator (a, b)` +*/ +function generatePair(genA, genB) { + var result = generatorBless(function (size) { + return [genA(size), genB(size)]; + }); + + return utils.curried3(result, arguments); +} + +/** + - `generator.either(genA: generator a, genB: generator b): generator (either a b)` +*/ +function generateEither(genA, genB) { + var result = generatorBless(function (size) { // eslint-disable-line consistent-return + var n = random(0, 1); + switch (n) { + case 0: return either.left(genA(size)); + case 1: return either.right(genB(size)); + // no default + } + }); + + return utils.curried3(result, arguments); +} +/** + - `generator.unit: generator ()` + + `unit` is an empty tuple, i.e. empty array in JavaScript representation. This is useful as a building block. +*/ +var generateUnit = generatorBless(function () { + return []; +}); + +/** + - `generator.tuple(gens: (generator a, generator b...)): generator (a, b...)` +*/ +function generateTuple(gens) { + var len = gens.length; + var result = generatorBless(function (size) { + var r = []; + for (var i = 0; i < len; i++) { + r[i] = gens[i](size); + } + return r; + }); + + return utils.curried2(result, arguments); +} + +/** + - `generator.sum(gens: (generator a, generator b...)): generator (a | b...)` +*/ +function generateSum(gens) { + var len = gens.length; + var result = generatorBless(function (size) { + var idx = random(0, len - 1); + return sum.addend(idx, len, gens[idx](size)); + }); + + return utils.curried2(result, arguments); +} + +/** + - `generator.array(gen: generator a): generator (array a)` +*/ +function generateArray(gen) { + var result = generatorBless(function (size) { + var arrsize = random(0, logsize(size)); + var arr = new Array(arrsize); + for (var i = 0; i < arrsize; i++) { + arr[i] = gen(size); + } + return arr; + }); + + return utils.curried2(result, arguments); +} + +/** + - `generator.nearray(gen: generator a): generator (array a)` +*/ +function generateNEArray(gen) { + var result = generatorBless(function (size) { + var arrsize = random(1, Math.max(logsize(size), 1)); + var arr = new Array(arrsize); + for (var i = 0; i < arrsize; i++) { + arr[i] = gen(size); + } + return arr; + }); + + return utils.curried2(result, arguments); +} + +/** + - `generator.dict(gen: generator a): generator (dict a)` +*/ + +module.exports = { + pair: generatePair, + either: generateEither, + unit: generateUnit, + tuple: generateTuple, + sum: generateSum, + array: generateArray, + nearray: generateNEArray, + oneof: generateOneof, + constant: generateConstant, + bless: generatorBless, + combine: generatorCombine, + recursive: generatorRecursive, +}; + +},{"./either.js":8,"./random.js":18,"./sum.js":26,"./utils.js":28,"assert":29}],14:[function(require,module,exports){ +"use strict"; + +var assert = require("assert"); + +var arbitraryBless = require("./arbitraryBless.js"); +var dict = require("./dict.js"); +var generator = require("./generator.js"); +var primitive = require("./primitive.js"); +var show = require("./show.js"); +var shrink = require("./shrink.js"); +var string = require("./string.js"); +var utils = require("./utils.js"); + +var nullArb = primitive.constant(null); + +var generateInteger = primitive.integer.generator; +var generateNumber = primitive.number.generator; +var generateBool = primitive.bool.generator; +var generateString = string.string.generator; +var generateNull = nullArb.generator; + +var generateJson = generator.recursive( + generator.oneof([ + generateInteger, + generateNumber, + generateBool, + generateString, + generateNull, + ]), + function (gen) { + return generator.oneof([generator.array(gen), dict.generator(gen)]); + }); + +// Forward declaration +var shrinkDictJson; +var shrinkJson; + +function shrinkRecJson(json) { + if (Array.isArray(json)) { + return shrink.array(shrinkJson, json); + } else { + return shrinkDictJson(json); + } +} + +shrinkJson = shrink.bless(function (json) { + assert(typeof json !== "function"); + + if (json === null) { + return nullArb.shrink(json); + } + + switch (typeof json) { + case "boolean": return primitive.bool.shrink(json); + case "number": return primitive.number.shrink(json); + case "string": return string.string.shrink(json); + default: return shrinkRecJson(json); + } +}); + +shrinkDictJson = (function () { + var pairShrink = shrink.pair(string.string.shrink, shrinkJson); + var arrayShrink = shrink.array(pairShrink); + + return arrayShrink.smap(utils.pairArrayToDict, utils.dictToPairArray); +}()); + +var json = arbitraryBless({ + generator: generateJson, + shrink: shrinkJson, + show: show.def, +}); + +module.exports = { + json: json, +}; + +},{"./arbitraryBless.js":4,"./dict.js":7,"./generator.js":13,"./primitive.js":17,"./show.js":21,"./shrink.js":22,"./string.js":24,"./utils.js":28,"assert":29}],15:[function(require,module,exports){ +/* @flow weak */ +/** + # JSVerify + + + + > Property-based checking. Like QuickCheck. + + [![Build Status](https://secure.travis-ci.org/jsverify/jsverify.svg?branch=master)](http://travis-ci.org/jsverify/jsverify) + [![NPM version](https://badge.fury.io/js/jsverify.svg)](http://badge.fury.io/js/jsverify) + [![Dependency Status](https://david-dm.org/jsverify/jsverify.svg)](https://david-dm.org/jsverify/jsverify) + [![devDependency Status](https://david-dm.org/jsverify/jsverify/dev-status.svg)](https://david-dm.org/jsverify/jsverify#info=devDependencies) + [![Code Climate](https://img.shields.io/codeclimate/github/jsverify/jsverify.svg)](https://codeclimate.com/github/jsverify/jsverify) + + ## Getting Started + + Install the module with: `npm install jsverify` + + ## Synopsis + + ```js + var jsc = require("jsverify"); + + // forall (f : bool -> bool) (b : bool), f (f (f b)) = f(b). + var boolFnAppliedThrice = + jsc.forall("bool -> bool", "bool", function (f, b) { + return f(f(f(b))) === f(b); + }); + + jsc.assert(boolFnAppliedThrice); + // OK, passed 100 tests + ``` +*/ +"use strict"; + +/** + ## Documentation + + ### Usage with [mocha](http://mochajs.org/) + + Using jsverify with mocha is easy, just define the properties and use `jsverify.assert`. + + Starting from version 0.4.3 you can write your specs without any boilerplate: + + ```js + describe("sort", function () { + jsc.property("idempotent", "array nat", function (arr) { + return _.isEqual(sort(sort(arr)), sort(arr)); + }); + }); + ``` + + Starting from version 0.8.0 you can write the specs in TypeScript. There are + typings provided. The drawback is that you cannot use type DSL: + + ```typescript + describe("basic jsverify usage", () => { + jsc.property("(b && b) === b", jsc.bool, b => (b && b) === b); + + jsc.property("boolean fn thrice", jsc.fn(jsc.bool), jsc.bool, (f, b) => + f(f(f(b))) === f(b) + ); + }); + ``` + + You can also provide `--jsverifyRngState state` command line argument, to run tests with particular random generator state. + + ``` + $ mocha examples/nat.js + + 1) natural numbers are less than 90: + Error: Failed after 49 tests and 1 shrinks. rngState: 074e9b5f037a8c21d6; Counterexample: 90; + + $ mocha examples/nat.js --grep 'are less than' --jsverifyRngState 074e9b5f037a8c21d6 + + 1) natural numbers are less than 90: + Error: Failed after 1 tests and 1 shrinks. rngState: 074e9b5f037a8c21d6; Counterexample: 90; + ``` + + Erroneous case is found with first try. + + ### Usage with [jasmine](https://jasmine.github.io/) + + Check [jasmineHelpers.js](helpers/jasmineHelpers.js) and [jasmineHelpers2.js](helpers/jasmineHelpers2.js) for jasmine 1.3 and 2.0 respectively. + + ## API Reference + + > _Testing shows the presence, not the absence of bugs._ + > + > Edsger W. Dijkstra + + To show that propositions hold, we need to construct proofs. + There are two extremes: proof by example (unit tests) and formal (machine-checked) proof. + Property-based testing is somewhere in between. + We formulate propositions, invariants or other properties we believe to hold, but + only test it to hold for numerous (randomly generated) values. + + Types and function signatures are written in [Coq](http://coq.inria.fr/)/[Haskell](http://www.haskell.org/haskellwiki/Haskell)-influenced style: + C# -style `List filter(List v, Func predicate)` is represented by + `filter(v: array T, predicate: T -> bool): array T` in our style. + + Methods and objects live in `jsc` object, e.g. `shrink.bless` method is used by + ```js + var jsc = require("jsverify"); + var foo = jsc.shrink.bless(...); + ``` + + Methods starting with `.dot` are prototype methods: + ```js + var arb = jsc.nat; + var arb2 = jsc.nat.smap(f, g); + ``` + + `jsverify` can operate with both synchronous and asynchronous-promise properties. + Generally every property can be wrapped inside [functor](http://learnyouahaskell.com/functors-applicative-functors-and-monoids), + for now in either identity or promise functor, for synchronous and promise properties respectively. +*/ + +var assert = require("assert"); +var lazyseq = require("lazy-seq"); + +var api = require("./api.js"); +var either = require("./either.js"); +var environment = require("./environment.js"); +var FMap = require("./finitemap.js"); +var fn = require("./fn.js"); +var functor = require("./functor.js"); +var random = require("./random.js"); +var show = require("./show.js"); +var shrink = require("./shrink.js"); +var suchthat = require("./suchthat.js"); +var sum = require("./sum.js"); +var typify = require("./typify.js"); +var utils = require("./utils.js"); + +/** + ### Properties +*/ + +function shrinkResult(arbs, x, test, size, shrinksN, exc, transform) { + assert(arbs.length === x.length, "shrinkResult: arbs and x has to be of same size"); + assert(typeof size === "number", "shrinkResult: size should be number"); + assert(typeof shrinksN === "number", "shrinkResult: shrinkN should be number"); + + var shrinks = utils.pluck(arbs, "shrink"); + var shows = utils.pluck(arbs, "show"); + + var shrinked = shrink.tuple(shrinks, x); + + var shrinkP = lazyseq.fold(shrinked, true, function (y, rest) { + var t = test(size, y, shrinksN + 1); + return functor.map(t, function (tprime) { + return tprime !== true ? tprime : rest(); + }); + }); + + return functor.map(shrinkP, function (shrinkPPrime) { + if (shrinkPPrime === true) { + var res = { + counterexample: x, + counterexamplestr: show.tuple(shows, x), + shrinks: shrinksN, + exc: exc, + }; + return transform(res); + } else { + return shrinkPPrime; + } + }); +} + +function isArbitrary(arb) { + return (typeof arb === "object" || typeof arb === "function") && + typeof arb.generator === "function" && + typeof arb.shrink === "function" && + typeof arb.show === "function"; +} + +/** + - `forall(arbs: arbitrary a ..., userenv: (map arbitrary)?, prop : a -> property): property` + + Property constructor +*/ +function forall() { + var args = Array.prototype.slice.call(arguments); + var gens = args.slice(0, -1); + var property = args[args.length - 1]; + var env; + + var lastgen = gens[gens.length - 1]; + + if (!isArbitrary(lastgen) && typeof lastgen !== "string") { + env = utils.merge(environment, lastgen); + gens = gens.slice(0, -1); + } else { + env = environment; + } + + assert(gens.length > 0, "forall requires at least single generator"); + + // Map typify-dsl to hard generators + gens = gens.map(function (g) { + g = typeof g === "string" ? typify.parseTypify(env, g) : g; + return utils.force(g); + }); + + assert(typeof property === "function", "property should be a function"); + + function test(size, x, shrinks) { + assert(Array.isArray(x), "generators results should be always tuple"); + + return functor.bind(property, x, function (r, exc) { + if (r === true) { + return true; + } else if (typeof r === "function") { + var rRec = r(size); + + return functor.map(rRec, function (rRecPrime) { + if (rRecPrime === true) { + return true; + } else { + return shrinkResult(gens, x, test, size, shrinks, exc, function (rr) { + return { + counterexample: rr.counterexample.concat(rRecPrime.counterexample), + counterexamplestr: rr.counterexamplestr, // + "; " + rRec.counterexamplestr, + shrinks: rr.shrinks, + exc: rr.exc || rRecPrime.exc, + }; + }); + } + }); + } else { + return shrinkResult(gens, x, test, size, shrinks, exc || r, utils.identity); + } + }); + } + + return function (size) { + var x = gens.map(function (arb) { return arb.generator(size); }); + var r = test(size, x, 0); + return r; + }; +} + +function formatFailedCase(r, state, includeStack) { + var msg = "Failed after " + r.tests + " tests and " + r.shrinks + " shrinks. "; + msg += "rngState: " + (r.rngState || state) + "; "; + msg += "Counterexample: " + r.counterexamplestr + "; "; + if (r.exc) { + if (r.exc instanceof Error) { + msg += "Exception: " + r.exc.message; + if (includeStack) { + msg += "\nStack trace: " + r.exc.stack; + } + } else { + msg += "Error: " + r.exc; + } + } + return msg; +} + +function findRngState(argv) { // eslint-disable-line consistent-return + for (var i = 0; i < argv.length - 1; i++) { + if (argv[i] === "--jsverifyRngState") { + return argv[i + 1]; + } + } +} + +/** + - `check (prop: property, opts: checkoptions?): result` + + Run random checks for given `prop`. If `prop` is promise based, result is also wrapped in promise. + + Options: + - `opts.tests` - test count to run, default 100 + - `opts.size` - maximum size of generated values, default 50 + - `opts.quiet` - do not `console.log` + - `opts.rngState` - state string for the rng + + The `result` is `true` if check succeeds, otherwise it's an object with various fields: + - `counterexample` - an input for which property fails. + - `tests` - number of tests run before failing case is found + - `shrinks` - number of shrinks performed + - `exc` - an optional exception thrown by property function + - `rngState` - random number generator's state before execution of the property +*/ +function check(property, opts) { + opts = opts || {}; + opts.size = opts.size || 50; + opts.tests = opts.tests || 100; + opts.quiet = opts.quiet || false; + + assert(typeof property === "function", "property should be a function"); + + var state; + + if (opts.rngState) { + random.setStateString(opts.rngState); + } else if (typeof process !== "undefined") { + var argvState = findRngState(process.argv); + if (argvState) { + random.setStateString(argvState); + } + } + + function loop(i) { + state = random.currentStateString(); + if (i > opts.tests) { + return true; + } + + var size = random(0, opts.size); + + // wrap non-promises in trampoline + var r = functor.pure(property(size)); + + return functor.map(r, function (rPrime) { + if (rPrime === true) { + return loop(i + 1); + } else { + rPrime.tests = i; + /* global console */ + if (!opts.quiet) { + console.error(formatFailedCase(rPrime, state, true), rPrime.counterexample); + } + return rPrime; + } + }); + } + + return functor.run(functor.map(loop(1), function (r) { + if (r === true) { + if (!opts.quiet) { console.info("OK, passed " + opts.tests + " tests"); } + } else { + r.rngState = state; + } + + return r; + })); +} + +/** + - `assert(prop: property, opts: checkoptions?) : void` + + Same as `check`, but throw exception if property doesn't hold. +*/ +function checkThrow(property, opts) { + opts = opts || {}; + if (opts.quiet === undefined) { + opts.quiet = true; + } + + return functor.run(functor.map(check(property, opts), function (r) { + if (r !== true) { + if (r.exc instanceof Error) { + r.exc.message = formatFailedCase(r); + throw r.exc; + } else { + throw new Error(formatFailedCase(r)); + } + } + })); +} + +/** + - `property(name: string, ...)` + + Assuming there is globally defined `it`, the same as: + + ```js + it(name, function () { + jsc.assert(jsc.forall(...)); + } + ``` + + You can use `property` to write facts too: + ```js + jsc.property("+0 === -0", function () { + return +0 === -0; + }); + ``` +*/ +function bddProperty(name) { + /* global it: true */ + var args = Array.prototype.slice.call(arguments, 1); + if (args.length === 1) { + it(name, function () { + return functor.run(functor.map(args[0](), function (result) { // eslint-disable-line consistent-return + if (typeof result === "function") { + return checkThrow(result); + } else if (result !== true) { + throw new Error(name + " doesn't hold"); + } + })); + }); + } else { + var prop = forall.apply(undefined, args); + it(name, function () { + return checkThrow(prop); + }); + } + /* global it: false */ +} + +/** + - `compile(desc: string, env: typeEnv?): arbitrary a` + + Compile the type description in provided type environment, or default one. +*/ +function compile(str, env) { + env = env ? utils.merge(environment, env) : environment; + return typify.parseTypify(env, str); +} + +/** + - `sampler(arb: arbitrary a, genSize: nat = 10): (sampleSize: nat?) -> a` + + Create a sampler for a given arbitrary with an optional size. Handy when used in + a REPL: + ``` + > jsc = require('jsverify') // or require('./lib/jsverify') w/in the project + ... + > jsonSampler = jsc.sampler(jsc.json, 4) + [Function] + > jsonSampler() + 0.08467432763427496 + > jsonSampler() + [ [ [] ] ] + > jsonSampler() + '' + > sampledJson(2) + [-0.4199344692751765, false] + ``` +*/ +function sampler(arb, size) { + size = typeof size === "number" ? Math.abs(size) : 10; + return function (count) { + if (typeof count === "number") { + var acc = []; + count = Math.abs(count); + for (var i = 0; i < count; i++) { + acc.push(arb.generator(size)); + } + return acc; + } else { + return arb.generator(size); + } + }; +} + +/** + - `throws(block: () -> a, error: class?, message: string?): bool` + + Executes nullary function `block`. Returns `true` if `block` throws. See [assert.throws](https://nodejs.org/api/assert.html#assert_assert_throws_block_error_message) +*/ +function throws(block, error, message) { + assert(error === undefined || typeof error === "function", "throws: error parameter must be a constructor"); + assert(message === undefined || typeof message === "string", "throws: message parameter must be a string"); + + try { + block(); + return false; + } catch (e) { + if (error !== undefined) { + if (e instanceof error) { + return message === undefined || e.message === message; + } else { + return false; + } + } else { + return true; + } + } +} + +/** + - `assertForall(arbs: arbitrary a ..., userenv: (map arbitrary)?, prop : a -> property): void` + + Combines 'assert' and 'forall'. + Constructs a property with forall from arguments, then throws an exception if the property doesn't hold. + Options for 'assert' cannot be set here - use assert(forall(...)) if you need that. +*/ +function assertForall() { + return checkThrow(forall.apply(null, arguments)); +} + +/** + - `checkForall(arbs: arbitrary a ..., userenv: (map arbitrary)?, prop : a -> property): result` + + Combines 'check' and 'forall'. + Constructs a property with forall from arguments, and returns a value based on if the property holds or not. + See 'check' for description of return value. + + Options for 'check' cannot be set here - use check(forall(...)) if you need that. +*/ +function checkForall() { + return check(forall.apply(null, arguments)); +} + +/** + ### Types + + - `generator a` is a function `(size: nat) -> a`. + - `show` is a function `a -> string`. + - `shrink` is a function `a -> [a]`, returning *smaller* values. + - `arbitrary a` is a triple of generator, shrink and show functions. + - `{ generator: nat -> a, shrink : a -> array a, show: a -> string }` + + ### Blessing + + We chose to represent generators and shrinks by functions, yet we would + like to have additional methods on them. Thus we *bless* objects with + additional properties. + + Usually you don't need to bless anything explicitly, as all combinators + return blessed values. + + See [perldoc for bless](http://perldoc.perl.org/functions/bless.html). +*/ + +/// include ./typify.js +/// include ./arbitraryBless.js +/// include ./bless.js +/// include ./primitive.js +/// include ./arbitrary.js +/// include ./recordWithEnv.js +/// include ./record.js +/// include ./string.js +/// include ./fn.js +/// include ./small.js +/// include ./suchthat.js +/// include ./generator.js +/// include ./shrink.js +/// include ./show.js +/// include ./random.js +/// include ./either.js +/// include ./utils.js + +// Export +var jsc = { + forall: forall, + check: check, + assert: checkThrow, + assertForall: assertForall, + checkForall: checkForall, + property: bddProperty, + sampler: sampler, + throws: throws, + + // generators + fn: fn.fn, + fun: fn.fn, + suchthat: suchthat.suchthat, + + // either + left: either.left, + right: either.right, + + // sum + addend: sum.addend, + + // compile + compile: compile, + + generator: api.generator, + shrink: api.shrink, + + // internal utility lib + random: random, + + show: show, + utils: utils, + _: { + FMap: FMap, + }, +}; + +/* primitives */ +/* eslint-disable guard-for-in */ +for (var k in api.arbitrary) { + jsc[k] = api.arbitrary[k]; +} +/* eslint-enable guard-for-in */ + +module.exports = jsc; + +/// plain ../FAQ.md +/// plain ../CONTRIBUTING.md +/// plain ../CHANGELOG.md +/// plain ../related-work.md +/// plain ../LICENSE + +},{"./api.js":1,"./either.js":8,"./environment.js":9,"./finitemap.js":10,"./fn.js":11,"./functor.js":12,"./random.js":18,"./show.js":21,"./shrink.js":22,"./suchthat.js":25,"./sum.js":26,"./typify.js":27,"./utils.js":28,"assert":29,"lazy-seq":30}],16:[function(require,module,exports){ +"use strict"; + +var arbitraryAssert = require("./arbitraryAssert.js"); +var arbitraryBless = require("./arbitraryBless.js"); +var generator = require("./generator.js"); +var show = require("./show.js"); +var shrink = require("./shrink.js"); +var utils = require("./utils.js"); + +function pair(a, b) { + a = utils.force(a); + b = utils.force(b); + + arbitraryAssert(a); + arbitraryAssert(b); + + return arbitraryBless({ + generator: generator.pair(a.generator, b.generator), + shrink: shrink.pair(a.shrink, b.shrink), + show: show.pair(a.show, b.show), + }); +} + +module.exports = { + pair: pair, +}; + +},{"./arbitraryAssert.js":3,"./arbitraryBless.js":4,"./generator.js":13,"./show.js":21,"./shrink.js":22,"./utils.js":28}],17:[function(require,module,exports){ +/* @flow weak */ +"use strict"; + +var arbitraryBless = require("./arbitraryBless"); +var assert = require("assert"); +var generator = require("./generator.js"); +var random = require("./random.js"); +var show = require("./show.js"); +var shrink = require("./shrink.js"); +var utils = require("./utils.js"); + +/** + ### Primitive arbitraries +*/ + +function extendWithDefault(arb) { + var def = arb(); + arb.generator = def.generator; + arb.shrink = def.shrink; + arb.show = def.show; + arb.smap = def.smap; +} + +function numeric(impl) { + return function (minsize, maxsize) { + if (arguments.length === 2) { + var arb = arbitraryBless(impl(maxsize - minsize)); + var to = function to(x) { + return Math.abs(x) + minsize; + }; + var from = function from(x) { + return x - minsize; + }; + + return arb.smap(to, from); + } else if (arguments.length === 1) { + return arbitraryBless(impl(minsize /* as maxsize */)); + } else { + return arbitraryBless(impl()); + } + }; +} + +/** + - `integer: arbitrary integer` + - `integer(maxsize: nat): arbitrary integer` + - `integer(minsize: integer, maxsize: integer): arbitrary integer` + + Integers, ℤ +*/ +var integer = numeric(function integer(maxsize) { + return { + generator: generator.bless(function (size) { + size = maxsize === undefined ? size : maxsize; + return random(-size, size); + }), + shrink: shrink.bless(function (i) { + assert(typeof i === "number", "integer.shrink have to be a number"); + + i = Math.abs(i); + if (i === 0) { + return []; + } else { + var arr = [0]; + var j = utils.div2(i); + var k = Math.max(j, 1); + while (j < i) { + arr.push(j); + arr.push(-j); + k = Math.max(utils.div2(k), 1); + j += k; + } + return arr; + } + }), + + show: show.def, + }; +}); + +extendWithDefault(integer); + +/** + - `nat: arbitrary nat` + - `nat(maxsize: nat): arbitrary nat` + + Natural numbers, ℕ (0, 1, 2...) +*/ +function nat(maxsize) { + return arbitraryBless({ + generator: generator.bless(function (size) { + size = maxsize === undefined ? size : maxsize; + return random(0, size); + }), + shrink: shrink.bless(function (i) { + assert(typeof i === "number", "nat.shrink have to be a number"); + + var arr = []; + var j = utils.div2(i); + var k = Math.max(j, 1); + while (j < i) { + arr.push(j); + k = Math.max(utils.div2(k), 1); + j += k; + } + return arr; + }), + show: show.def, + }); +} + +extendWithDefault(nat); + +/** + - `number: arbitrary number` + - `number(maxsize: number): arbitrary number` + - `number(min: number, max: number): arbitrary number` + + JavaScript numbers, "doubles", ℝ. `NaN` and `Infinity` are not included. +*/ +var number = numeric(function number(maxsize) { + return { + generator: generator.bless(function (size) { + size = maxsize === undefined ? size : maxsize; + return random.number(-size, size); + }), + shrink: shrink.bless(function (x) { + assert(typeof x === "number", "number.shrink have to be a number"); + + if (Math.abs(x) > 1e-6) { + return [0, x / 2, -x / 2]; + } else { + return []; + } + }), + show: show.def, + }; +}); + +extendWithDefault(number); + +/** + - `uint8: arbitrary nat` + - `uint16: arbitrary nat` + - `uint32: arbitrary nat` +*/ +var uint8 = nat(0xff); +var uint16 = nat(0xffff); +var uint32 = nat(0xffffffff); + +/** + - `int8: arbitrary integer` + - `int16: arbitrary integer` + - `int32: arbitrary integer` +*/ +var int8 = integer(-0x80, 0x7f); +var int16 = integer(-0x8000, 0x7fff); +var int32 = integer(-0x80000000, 0x7fffffff); + +/** + - `bool: arbitrary bool` + + Booleans, `true` or `false`. +*/ +var bool = arbitraryBless({ + generator: generator.bless(function (/* size */) { + var i = random(0, 1); + return i === 1; + }), + + shrink: shrink.bless(function (b) { + assert(b === true || b === false, "bool.shrink excepts true or false"); + return b === true ? [false] : []; + }), + show: show.def, +}); + +/** + - `datetime: arbitrary datetime` + + Random datetime +*/ +var datetimeConst = 1416499879495; // arbitrary datetime + +function datetime(from, to) { + var toDate; + var fromDate; + var arb; + + if (arguments.length === 2) { + toDate = function toDateFn(x) { + return new Date(x); + }; + fromDate = function fromDateFn(x) { + return x.getTime(); + }; + from = fromDate(from); + to = fromDate(to); + arb = number(from, to); + + return arb.smap(toDate, fromDate); + } else { + toDate = function toDateFn(x) { + return new Date(x * 768000000 + datetimeConst); + }; + arb = number; + + return arbitraryBless({ + generator: arb.generator.map(toDate), + shrink: shrink.noop, + show: show.def, + }); + } +} + +extendWithDefault(datetime); + +/** + - `elements(args: array a): arbitrary a` + + Random element of `args` array. +*/ +function elements(args) { + assert(args.length !== 0, "elements: at least one parameter expected"); + + return arbitraryBless({ + generator: generator.bless(function (/* size */) { + var i = random(0, args.length - 1); + return args[i]; + }), + + shrink: shrink.bless(function (x) { + var idx = args.indexOf(x); + if (idx <= 0) { + return []; + } else { + return args.slice(0, idx); + } + }), + show: show.def, + }); +} + +/** + - `falsy: arbitrary *` + + Generates falsy values: `false`, `null`, `undefined`, `""`, `0`, and `NaN`. +*/ +var falsy = elements([false, null, undefined, "", 0, NaN]); +falsy.show = function (v) { + if (v !== v) { + return "falsy: NaN"; + } else if (v === "") { + return "falsy: empty string"; + } else if (v === undefined) { + return "falsy: undefined"; + } else { + return "falsy: " + v; + } +}; + +/** + - `constant(x: a): arbitrary a` + + Returns an unshrinkable arbitrary that yields the given object. +*/ +function constant(x) { + return arbitraryBless({ + generator: generator.constant(x), + shrink: shrink.noop, + show: show.def, + }); +} + +module.exports = { + integer: integer, + nat: nat, + int8: int8, + int16: int16, + int32: int32, + uint8: uint8, + uint16: uint16, + uint32: uint32, + number: number, + elements: elements, + bool: bool, + falsy: falsy, + constant: constant, + datetime: datetime, +}; + +},{"./arbitraryBless":4,"./generator.js":13,"./random.js":18,"./show.js":21,"./shrink.js":22,"./utils.js":28,"assert":29}],18:[function(require,module,exports){ +/* @flow weak */ +"use strict"; + +var rc4 = new (require("rc4").RC4small)(); + +/** + ### Random functions +*/ + +/** + - `random(min: int, max: int): int` + + Returns random int from `[min, max]` range inclusively. + + ```js + getRandomInt(2, 3) // either 2 or 3 + ``` +*/ +function randomInteger(min, max) { + return rc4.random(min, max); +} + +/** + - `random.number(min: number, max: number): number` + + Returns random number from `[min, max)` range. +*/ +function randomNumber(min, max) { + return rc4.randomFloat() * (max - min) + min; +} + +randomInteger.integer = randomInteger; +randomInteger.number = randomNumber; + +randomInteger.currentStateString = rc4.currentStateString.bind(rc4); +randomInteger.setStateString = rc4.setStateString.bind(rc4); + +module.exports = randomInteger; + +},{"rc4":31}],19:[function(require,module,exports){ +"use strict"; + +var arbitraryBless = require("./arbitraryBless.js"); +var generator = require("./generator.js"); +var utils = require("./utils.js"); +var shrink = require("./shrink.js"); + +/** + - `generator.record(gen: { key: generator a... }): generator { key: a... }` +*/ +function generatorRecord(spec) { + var keys = Object.keys(spec); + var result = generator.bless(function (size) { + var res = {}; + keys.forEach(function (k) { + res[k] = spec[k](size); + }); + return res; + }); + + return utils.curried2(result, arguments); +} + +/** + - `shrink.record(shrs: { key: shrink a... }): shrink { key: a... }` +*/ +function shrinkRecord(shrinksRecord) { + var keys = Object.keys(shrinksRecord); + var shrinks = keys.map(function (k) { return shrinksRecord[k]; }); + + var result = shrink.bless(function (rec) { + var values = keys.map(function (k) { return rec[k]; }); + var shrinked = shrink.tuple(shrinks, values); + + return shrinked.map(function (s) { + var res = {}; + keys.forEach(function (k, i) { + res[k] = s[i]; + }); + return res; + }); + }); + + return utils.curried2(result, arguments); +} + +function arbitraryRecord(spec) { + var generatorSpec = {}; + var shrinkSpec = {}; + var showSpec = {}; + + Object.keys(spec).forEach(function (k) { + var arb = utils.force(spec[k]); + generatorSpec[k] = arb.generator; + shrinkSpec[k] = arb.shrink; + showSpec[k] = arb.show; + }); + + return arbitraryBless({ + generator: generatorRecord(generatorSpec), + shrink: shrinkRecord(shrinkSpec), + show: function (m) { + return "{" + Object.keys(m).map(function (k) { + return k + ": " + showSpec[k](m[k]); + }).join(", ") + "}"; + }, + }); +} + +module.exports = { + generator: generatorRecord, + arbitrary: arbitraryRecord, + shrink: shrinkRecord, +}; + +},{"./arbitraryBless.js":4,"./generator.js":13,"./shrink.js":22,"./utils.js":28}],20:[function(require,module,exports){ +"use strict"; + +var environment = require("./environment.js"); +var record = require("./record.js"); +var typify = require("./typify.js"); +var utils = require("./utils.js"); + +/** + ### Arbitrary records + + - `record(spec: { key: arbitrary a... }, userenv: env?): arbitrary { key: a... }` + + Generates a javascript object with given record spec. +*/ +function recordWithEnv(spec, userenv) { + var env = userenv ? utils.merge(environment, userenv) : environment; + + var parsedSpec = {}; + Object.keys(spec).forEach(function (k) { + var arb = spec[k]; + parsedSpec[k] = typeof arb === "string" ? typify.parseTypify(env, arb) : arb; + }); + + return record.arbitrary(parsedSpec); +} + +module.exports = recordWithEnv; + +},{"./environment.js":9,"./record.js":19,"./typify.js":27,"./utils.js":28}],21:[function(require,module,exports){ + +/* @flow weak */ +"use strict"; + +/** + ### Show functions +*/ + +var utils = require("./utils.js"); + +/** + - `show.def(x : a): string` + + Currently implemented as `JSON.stringify`. +*/ +function showDef(obj) { + return JSON.stringify(obj); +} + +/** + - `show.pair(showA: a -> string, showB: b -> string, x: (a, b)): string` +*/ +function showPair(showA, showB) { + var result = function (p) { + return "(" + showA(p[0]) + ", " + showB(p[1]) + ")"; + }; + + return utils.curried3(result, arguments); +} + +/** + - `show.either(showA: a -> string, showB: b -> string, e: either a b): string` +*/ +function showEither(showA, showB) { + function showLeft(value) { + return "Left(" + showA(value) + ")"; + } + + function showRight(value) { + return "Right(" + showB(value) + ")"; + } + + var result = function (e) { + return e.either(showLeft, showRight); + }; + + return utils.curried3(result, arguments); +} + +/** + - `show.tuple(shrinks: (a -> string, b -> string...), x: (a, b...)): string` +*/ +function showTuple(shows) { + var result = function (objs) { + var strs = []; + for (var i = 0; i < shows.length; i++) { + strs.push(shows[i](objs[i])); + } + return strs.join("; "); + }; + + return utils.curried2(result, arguments); +} + +/** + - `show.sum(shrinks: (a -> string, b -> string...), x: (a | b ...)): string` +*/ +function showSum(shows) { + var result = function (sum) { + return sum.fold(function (idx, n, value) { + return "Sum(" + idx + "/" + n + ": " + shows[idx](value) + ")"; + }); + }; + + return utils.curried2(result, arguments); +} + +/** + - `show.array(shrink: a -> string, x: array a): string` +*/ +function showArray(show) { + var result = function (arr) { + return "[" + arr.map(show).join(", ") + "]"; + }; + + return utils.curried2(result, arguments); +} + +module.exports = { + def: showDef, + pair: showPair, + either: showEither, + tuple: showTuple, + sum: showSum, + array: showArray, +}; + +},{"./utils.js":28}],22:[function(require,module,exports){ +/* @flow weak */ +"use strict"; + +var assert = require("assert"); +var either = require("./either.js"); +var lazyseq = require("lazy-seq"); +var sum = require("./sum.js"); +var utils = require("./utils.js"); + +/** + ### Shrink functions + + A shrink function, `shrink a`, is a function `a -> [a]`, returning an array of *smaller* values. + + Shrink combinators are auto-curried: + + ```js + var xs = jsc.shrink.array(jsc.nat.shrink, [1]); // ≡ + var ys = jsc.shrink.array(jsc.nat.shrink)([1]); + ``` +*/ + +// Blessing: i.e adding prototype +/* eslint-disable no-use-before-define */ +function shrinkProtoIsoMap(f, g) { + /* jshint validthis:true */ + var shrink = this; // eslint-disable-line no-invalid-this + return shrinkBless(function (value) { + return shrink(g(value)).map(f); + }); +} +/* eslint-enable no-use-before-define */ + +/** + - `shrink.bless(f: a -> [a]): shrink a` + + Bless function with `.smap` property. + + - `.smap(f: a -> b, g: b -> a): shrink b` + + Transform `shrink a` into `shrink b`. For example: + + ```js + positiveIntegersShrink = nat.shrink.smap( + function (x) { return x + 1; }, + function (x) { return x - 1; }); + ``` +*/ +function shrinkBless(shrink) { + shrink.smap = shrinkProtoIsoMap; + return shrink; +} + +/** + - `shrink.noop: shrink a` +*/ +var shrinkNoop = shrinkBless(function shrinkNoop() { + return []; +}); + +/** + - `shrink.pair(shrA: shrink a, shrB: shrink b): shrink (a, b)` +*/ +function shrinkPair(shrinkA, shrinkB) { + var result = shrinkBless(function (pair) { + assert(pair.length === 2, "shrinkPair: pair should be an Array of length 2"); + + var a = pair[0]; + var b = pair[1]; + + var shrinkedA = shrinkA(a); + var shrinkedB = shrinkB(b); + + var pairA = shrinkedA.map(function (ap) { + return [ap, b]; + }); + + if (Array.isArray(pairA)) { + pairA = lazyseq.fromArray(pairA); + } + + return pairA.append(function () { + var pairB = shrinkedB.map(function (bp) { + return [a, bp]; + }); + return pairB; + }); + }); + + return utils.curried3(result, arguments); +} + +/** + - `shrink.either(shrA: shrink a, shrB: shrink b): shrink (either a b)` +*/ +function shrinkEither(shrinkA, shrinkB) { + function shrinkLeft(value) { + return shrinkA(value).map(either.left); + } + + function shrinkRight(value) { + return shrinkB(value).map(either.right); + } + + var result = shrinkBless(function (e) { + return e.either(shrinkLeft, shrinkRight); + }); + + return utils.curried3(result, arguments); +} + +// We represent non-empty linked list as +// singl x = [x] +// cons h t = [h, t] +function fromLinkedList(ll) { + assert(ll.length === 1 || ll.length === 2, "linked list must be either [] or [x, linkedlist]"); + if (ll.length === 1) { + return [ll[0]]; + } else { + return [ll[0]].concat(fromLinkedList(ll[1])); + } +} + +function toLinkedList(arr) { + assert(Array.isArray(arr) && arr.length > 0, "toLinkedList expects non-empty array"); + if (arr.length === 1) { + return [arr[0]]; + } else { + return [arr[0], toLinkedList(arr.slice(1))]; + } +} + +function toSingleton(x) { + return [x]; +} + +// Vec a 1 → a +function fromSingleton(a) { + return a[0]; +} + +function flattenShrink(shrinksLL) { + if (shrinksLL.length === 1) { + return shrinksLL[0].smap(toSingleton, fromSingleton); + } else { + var head = shrinksLL[0]; + var tail = shrinksLL[1]; + return shrinkPair(head, flattenShrink(tail)); + } +} + +/** + - `shrink.tuple(shrs: (shrink a, shrink b...)): shrink (a, b...)` +*/ +function shrinkTuple(shrinks) { + assert(shrinks.length > 0, "shrinkTuple needs > 0 values"); + var shrinksLL = toLinkedList(shrinks); + var shrink = flattenShrink(shrinksLL); + var result = shrinkBless(function (tuple) { + assert(tuple.length === shrinks.length, "shrinkTuple: not-matching params"); + var ll = toLinkedList(tuple); + return shrink(ll).map(fromLinkedList); + }); + + return utils.curried2(result, arguments); +} + +/** + - `shrink.sum(shrs: (shrink a, shrink b...)): shrink (a | b...)` +*/ +function shrinkSum(shrinks) { + assert(shrinks.length > 0, "shrinkTuple needs > 0 values"); + var result = shrinkBless(function (s) { + return s.fold(function (idx, len, value) { + assert(len === shrinks.length, "shrinkSum: not-matching params"); + return shrinks[idx](value).map(function (shrinked) { + return sum.addend(idx, len, shrinked); + }); + }); + }); + + return utils.curried2(result, arguments); +} + +function shrinkArrayWithMinimumSize(size) { + function shrinkArrayImpl(shrink) { + var result = shrinkBless(function (arr) { + assert(Array.isArray(arr), "shrinkArrayImpl() expects array, got: " + arr); + if (arr.length <= size) { + return lazyseq.nil; + } else { + var x = arr[0]; + var xs = arr.slice(1); + + return lazyseq.cons(xs, lazyseq.nil) + .append(shrink(x).map(function (xp) { return [xp].concat(xs); })) + .append(shrinkArrayImpl(shrink, xs).map(function (xsp) { return [x].concat(xsp); })); + } + }); + + return utils.curried2(result, arguments); + } + + return shrinkArrayImpl; +} + +/** + - `shrink.array(shr: shrink a): shrink (array a)` +*/ +var shrinkArray = shrinkArrayWithMinimumSize(0); + +/** + - `shrink.nearray(shr: shrink a): shrink (nearray a)` +*/ +var shrinkNEArray = shrinkArrayWithMinimumSize(1); + +module.exports = { + noop: shrinkNoop, + pair: shrinkPair, + either: shrinkEither, + tuple: shrinkTuple, + sum: shrinkSum, + array: shrinkArray, + nearray: shrinkNEArray, + bless: shrinkBless, +}; + +},{"./either.js":8,"./sum.js":26,"./utils.js":28,"assert":29,"lazy-seq":30}],23:[function(require,module,exports){ +"use strict"; + +var generator = require("./generator.js"); +var arbitraryBless = require("./arbitraryBless.js"); +var arbitraryAssert = require("./arbitraryAssert.js"); +var utils = require("./utils.js"); + +/** + ### Small arbitraries + + - `generator.small(gen: generator a): generator a` + - `small(arb: arbitrary a): arbitrary a` + + Create a generator (abitrary) which will generate smaller values, i.e. generator's `size` parameter is decreased logarithmically. + + ```js + jsc.property("small array of small natural numbers", "small (array nat)", function (arr) { + return Array.isArray(arr); + }); + + jsc.property("small array of normal natural numbers", "(small array) nat", function (arr) { + return Array.isArray(arr); + }); + ``` +*/ + +function smallGenerator(gen) { + // TODO: assertGenerator(gen) + return generator.bless(function (size) { + return gen(utils.ilog2(size)); + }); +} + +function smallArbitraryImpl(arb) { + arbitraryAssert(arb); + return arbitraryBless({ + generator: smallGenerator(arb.generator), + shrink: arb.shrink, + show: arb.show, + }); +} + +function smallArbitrary(arb) { + if (typeof arb === "function") { + return function () { + var resArb = arb.apply(arb, arguments); + return smallArbitraryImpl(resArb); + }; + } else { /* if (typeof arb === "object") */ + return smallArbitraryImpl(arb); + } +} + +module.exports = { + generator: smallGenerator, + arbitrary: smallArbitrary, +}; + +},{"./arbitraryAssert.js":3,"./arbitraryBless.js":4,"./generator.js":13,"./utils.js":28}],24:[function(require,module,exports){ +"use strict"; + +var array = require("./array.js"); +var primitive = require("./primitive.js"); +var utils = require("./utils.js"); + +/** + ### Arbitrary strings +*/ + +function fromCode(code) { + return String.fromCharCode(code); +} + +function toCode(c) { + return c.charCodeAt(0); +} + +/** + - `char: arbitrary char` — Single character +*/ +var char = primitive.nat(0xff).smap(fromCode, toCode); + +/** + - `asciichar: arbitrary char` — Single ascii character (0x20-0x7e inclusive, no DEL) +*/ +var asciichar = primitive.integer(0x20, 0x7e).smap(fromCode, toCode); + +/** + - `string: arbitrary string` +*/ +var string = array.array(char).smap(utils.charArrayToString, utils.stringToCharArray); + +/** + - `nestring: arbitrary string` — Generates strings which are not empty. +*/ +var nestring = array.nearray(char).smap(utils.charArrayToString, utils.stringToCharArray); + +/** + - `asciistring: arbitrary string` +*/ +var asciistring = array.array(asciichar).smap(utils.charArrayToString, utils.stringToCharArray); + +/** + - `asciinestring: arbitrary string` +*/ +var asciinestring = array.nearray(asciichar).smap(utils.charArrayToString, utils.stringToCharArray); + +module.exports = { + char: char, + asciichar: asciichar, + string: string, + nestring: nestring, + asciistring: asciistring, + asciinestring: asciinestring, +}; + +},{"./array.js":5,"./primitive.js":17,"./utils.js":28}],25:[function(require,module,exports){ +/* @flow weak */ +"use strict"; + +var environment = require("./environment.js"); +var typify = require("./typify.js"); +var utils = require("./utils.js"); +var generator = require("./generator.js"); +var shrink = require("./shrink.js"); +var arbitraryBless = require("./arbitraryBless.js"); + +/** + ### Restricting arbitraries + + - `suchthat(arb: arbitrary a, userenv: env?, p : a -> bool): arbitrary a` + Arbitrary of values that satisfy `p` predicate. It's advised that `p`'s accept rate is high. +*/ +function suchthat(arb, userenv, predicate) { + var env; + if (arguments.length === 2) { + predicate = userenv; + env = environment; + } else { + env = utils.merge(environment, userenv); + } + + arb = typeof arb === "string" ? typify.parseTypify(env, arb) : arb; + arb = utils.force(arb); + + return arbitraryBless({ + generator: generator.bless(function (size) { + for (var i = 0; ; i++) { + // if 5 tries failed, increase size + if (i > 5) { + i = 0; + size += 1; + } + + var x = arb.generator(size); + if (predicate(x)) { + return x; + } + } + }), + + shrink: shrink.bless(function (x) { + return arb.shrink(x).filter(predicate); + }), + + show: arb.show, + }); +} + +module.exports = { + suchthat: suchthat, +}; + +},{"./arbitraryBless.js":4,"./environment.js":9,"./generator.js":13,"./shrink.js":22,"./typify.js":27,"./utils.js":28}],26:[function(require,module,exports){ +"use strict"; + +var assert = require("assert"); + +/** + ### sum (n-ary either) + + See: [Wikipedia](https://en.wikipedia.org/wiki/Tagged_union) +*/ + +function Addend(idx, len, value) { + assert(len > 0, "Addend: 0 < len"); // empty sum is void - cannot create such + assert(idx >= 0 && idx < len, "Addend: 0 <= idx < len"); + this.idx = idx; + this.len = len; + this.value = value; +} + +/** + - `sum.addend(idx: nat, n: nat, value: a): sum (... a ...)` +*/ +function addend(idx, len, value) { + return new Addend(idx, len, value); +} + +/** + - `.fold(f: (idx: nat, n: nat, value: a) -> b): b` +*/ +Addend.prototype.fold = function (f) { + return f(this.idx, this.len, this.value); +}; + +module.exports = { + addend: addend, +}; + +},{"assert":29}],27:[function(require,module,exports){ +/* @flow weak */ +"use strict"; + +/** + ### DSL for input parameters + + There is a small DSL to help with `forall`. For example the two definitions below are equivalent: + ```js + var bool_fn_applied_thrice = jsc.forall("bool -> bool", "bool", check); + var bool_fn_applied_thrice = jsc.forall(jsc.fn(jsc.bool), jsc.bool, check); + ``` + + The DSL is based on a subset of language recognized by [typify-parser](https://github.com/phadej/typify-parser): + - *identifiers* are fetched from the predefined environment. + - *applications* are applied as one could expect: `"array bool"` is evaluated to `jsc.array(jsc.bool)`. + - *functions* are supported: `"bool -> bool"` is evaluated to `jsc.fn(jsc.bool)`. + - *square brackets* are treated as a shorthand for the array type: `"[nat]"` is evaluated to `jsc.array(jsc.nat)`. + - *union*: `"bool | nat"` is evaluated to `jsc.sum([jsc.bool, jsc.nat])`. + - **Note** `oneof` cannot be shrunk, because the union is untagged, we don't know which shrink to use. + - *conjunction*: `"bool & nat"` is evaluated to `jsc.tuple(jsc.bool, jsc.nat)`. + - *anonymous records*: `"{ b: bool; n: nat }"` is evaluated to `jsc.record({ b: jsc.bool, n: jsc.nat })`. + - *EXPERIMENTAL: recursive types*: `"rec list -> unit | (nat & list)"`. +*/ + +var arbitrary = require("./arbitrary.js"); +var assert = require("assert"); +var record = require("./record.js"); +var array = require("./array.js"); +var fn = require("./fn.js"); +var typifyParser = require("typify-parser"); +var utils = require("./utils.js"); + +// Forward declarations +var compileType; +var compileTypeArray; + +function compileIdent(env, type) { + var g = env[type.value]; + if (!g) { + throw new Error("Unknown arbitrary: " + type.value); + } + return g; +} + +function compileApplication(env, type) { + var callee = compileType(env, type.callee); + var args = compileTypeArray(env, type.args); + + return callee.apply(undefined, args); +} + +function compileFunction(env, type) { + // we don't care about argument type + var result = compileType(env, type.result); + return fn.fn(result); +} + +function compileBrackets(env, type) { + var arg = compileType(env, type.arg); + return array.array(arg); +} + +function compileDisjunction(env, type) { + var args = compileTypeArray(env, type.args); + return arbitrary.sum(args); +} + +function compileConjunction(env, type) { + var args = compileTypeArray(env, type.args); + return arbitrary.tuple(args); +} + +function compileRecord(env, type) { + // TODO: use mapValues + var spec = {}; + Object.keys(type.fields).forEach(function (key) { + spec[key] = compileType(env, type.fields[key]); + }); + return record.arbitrary(spec); +} + +function compileRecursive(env, type) { + assert(type.arg.type === "disjunction", "recursive type's argument should be disjunction"); + + // bound variable + var name = type.name; + + var par = utils.partition(type.arg.args, function (t) { + return typifyParser.freeVars(t).indexOf(name) === -1; + }); + + var terminal = par[0]; + + if (terminal.length === 0) { + throw new Error("Recursive type without non-recursive branch"); + } + + var terminalArb = compileType(env, { + type: "disjunction", + args: terminal, + }); + + return arbitrary.recursive(terminalArb, function (arb) { + var arbEnv = {}; + arbEnv[name] = arb; + var newEnv = utils.merge(env, arbEnv); + return compileType(newEnv, type.arg); + }); +} + +compileType = function compileTypeFn(env, type) { + switch (type.type) { + case "ident": return compileIdent(env, type); + case "application": return compileApplication(env, type); + case "function": return compileFunction(env, type); + case "brackets": return compileBrackets(env, type); + case "disjunction": return compileDisjunction(env, type); + case "conjunction": return compileConjunction(env, type); + case "record": return compileRecord(env, type); + case "number": return type.value; + case "recursive": return compileRecursive(env, type); + default: throw new Error("Unsupported typify ast type: " + type.type); + } +}; + +compileTypeArray = function compileTypeArrayFn(env, types) { + return types.map(function (type) { + return compileType(env, type); + }); +}; + +function parseTypify(env, str) { + var type = typifyParser(str); + return compileType(env, type); +} + +module.exports = { + parseTypify: parseTypify, +}; + +},{"./arbitrary.js":2,"./array.js":5,"./fn.js":11,"./record.js":19,"./utils.js":28,"assert":29,"typify-parser":33}],28:[function(require,module,exports){ +/* @flow weak */ +"use strict"; + +var isArray = Array.isArray; +function isObject(o) { + /* eslint-disable no-new-object */ + return new Object(o) === o; + /* eslint-enable no-new-object */ +} + +/* undefined-safe isNaN */ +function isNaN(n) { + return typeof n === "number" && n !== n; +} + +/** + ### Utility functions + + Utility functions are exposed (and documented) only to make contributions to jsverify more easy. + The changes here don't follow semver, i.e. there might be backward-incompatible changes even in patch releases. + + Use [underscore.js](http://underscorejs.org/), [lodash](https://lodash.com/), [ramda](http://ramda.github.io/ramdocs/docs/), [lazy.js](http://danieltao.com/lazy.js/) or some other utility belt. +*/ + +/* Simple sort */ +function sort(arr) { + var res = arr.slice(); + res.sort(); + return res; +} + +/** + - `utils.isEqual(x: json, y: json): bool` + + Equality test for `json` objects. +*/ +function isEqual(a, b) { + var i; + + if (isNaN(a) && isNaN(b)) { + return true; + } + + if (a === b) { + return true; + } else if (isArray(a) && isArray(b) && a.length === b.length) { + for (i = 0; i < a.length; i++) { + if (!isEqual(a[i], b[i])) { + return false; + } + } + return true; + } else if (isObject(a) && isObject(b) && !isArray(a) && !isArray(b)) { + var akeys = Object.keys(a); + var bkeys = Object.keys(b); + if (!isEqual(sort(akeys), sort(bkeys))) { + return false; + } + + for (i = 0; i < akeys.length; i++) { + if (!isEqual(a[akeys[i]], b[akeys[i]])) { + return false; + } + } + return true; + } + + return false; +} + +/** + - `utils.isApproxEqual(x: a, y: b, opts: obj): bool` + + Tests whether two objects are approximately and optimistically equal. + Returns `false` only if they are distinguishable not equal. + Returns `true` when `x` and `y` are `NaN`. + This function works with cyclic data. + + Takes optional 'opts' parameter with properties: + + - `fnEqual` - whether all functions are considered equal (default: yes) + - `depth` - how deep to recurse until treating as equal (default: 5) +*/ +function isApproxEqual(x, y, opts) { + opts = opts || {}; + var fnEqual = opts.fnEqual !== false; + var depth = opts.depth || 5; // totally arbitrary + + // state contains pairs we checked (or are still checking, but assume equal!) + var state = []; + + function loop(a, b, n) { + if (isNaN(a) && isNaN(b)) { + return true; + } + + // trivial check + if (a === b) { + return true; + } + + // depth check + if (n >= depth) { + return true; + } + + var i; + + // check if pair already occured + for (i = 0; i < state.length; i++) { + if (state[i][0] === a && state[i][1] === b) { + return true; + } + } + + // add to state + state.push([a, b]); + + if (typeof a === "function" && typeof b === "function") { + return fnEqual; + } + + if (isArray(a) && isArray(b) && a.length === b.length) { + for (i = 0; i < a.length; i++) { + if (!loop(a[i], b[i], n + 1)) { + return false; + } + } + return true; + } else if (isObject(a) && isObject(b) && !isArray(a) && !isArray(b)) { + var akeys = Object.keys(a); + var bkeys = Object.keys(b); + if (!loop(sort(akeys), sort(bkeys), n + 1)) { + return false; + } + + for (i = 0; i < akeys.length; i++) { + if (!loop(a[akeys[i]], b[akeys[i]], n + 1)) { + return false; + } + } + return true; + } + + return false; + } + return loop(x, y, 0); +} + +function identity(x) { + return x; +} + +function pluck(arr, key) { + return arr.map(function (e) { + return e[key]; + }); +} + +/** + - `utils.force(x: a | () -> a) : a` + + Evaluate `x` as nullary function, if it is one. +*/ +function force(arb) { + return (typeof arb === "function") ? arb() : arb; +} + +/** + - `utils.merge(x... : obj): obj` + + Merge two objects, a bit like `_.extend({}, x, y)`. +*/ +function merge() { + var res = {}; + + for (var i = 0; i < arguments.length; i++) { + var arg = arguments[i]; + var keys = Object.keys(arg); + for (var j = 0; j < keys.length; j++) { + var key = keys[j]; + res[key] = arg[key]; + } + } + + return res; +} + +function div2(x) { + return Math.floor(x / 2); +} + +function log2(x) { + return Math.log(x) / Math.log(2); +} + +function ilog2(x) { + return x <= 0 ? 0 : Math.floor(log2(x)); +} + +function curriedN(n) { + var n1 = n - 1; + return function curriedNInstance(result, args) { + if (args.length === n) { + return result(args[n1]); + } else { + return result; + } + }; +} + +var curried2 = curriedN(2); +var curried3 = curriedN(3); + +function charArrayToString(arr) { + return arr.join(""); +} + +function stringToCharArray(str) { + return str.split(""); +} + +function pairArrayToDict(arrayOfPairs) { + var res = {}; + arrayOfPairs.forEach(function (p) { + res[p[0]] = p[1]; + }); + return res; +} + +function dictToPairArray(m) { + var res = []; + Object.keys(m).forEach(function (k) { + res.push([k, m[k]]); + }); + return res; +} + +function partition(arr, pred) { + var truthy = []; + var falsy = []; + + for (var i = 0; i < arr.length; i++) { + var x = arr[i]; + if (pred(x)) { + truthy.push(x); + } else { + falsy.push(x); + } + } + + return [truthy, falsy]; +} + +module.exports = { + isArray: isArray, + isObject: isObject, + isEqual: isEqual, + isApproxEqual: isApproxEqual, + identity: identity, + pluck: pluck, + force: force, + merge: merge, + div2: div2, + ilog2: ilog2, + curried2: curried2, + curried3: curried3, + charArrayToString: charArrayToString, + stringToCharArray: stringToCharArray, + pairArrayToDict: pairArrayToDict, + dictToPairArray: dictToPairArray, + partition: partition, +}; + +},{}],29:[function(require,module,exports){ +'use strict'; + +// compare and isBuffer taken from https://github.com/feross/buffer/blob/680e9e5e488f22aac27599a57dc844a6315928dd/index.js +// original notice: + +/*! + * The buffer module from node.js, for the browser. + * + * @author Feross Aboukhadijeh + * @license MIT + */ +function compare(a, b) { + if (a === b) { + return 0; + } + + var x = a.length; + var y = b.length; + + for (var i = 0, len = Math.min(x, y); i < len; ++i) { + if (a[i] !== b[i]) { + x = a[i]; + y = b[i]; + break; + } + } + + if (x < y) { + return -1; + } + if (y < x) { + return 1; + } + return 0; +} +function isBuffer(b) { + if (global.Buffer && typeof global.Buffer.isBuffer === 'function') { + return global.Buffer.isBuffer(b); + } + return !!(b != null && b._isBuffer); +} + +// based on node assert, original notice: + +// http://wiki.commonjs.org/wiki/Unit_Testing/1.0 +// +// THIS IS NOT TESTED NOR LIKELY TO WORK OUTSIDE V8! +// +// Originally from narwhal.js (http://narwhaljs.org) +// Copyright (c) 2009 Thomas Robinson <280north.com> +// +// Permission is hereby granted, free of charge, to any person obtaining a copy +// of this software and associated documentation files (the 'Software'), to +// deal in the Software without restriction, including without limitation the +// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or +// sell copies of the Software, and to permit persons to whom the Software is +// furnished to do so, subject to the following conditions: +// +// The above copyright notice and this permission notice shall be included in +// all copies or substantial portions of the Software. +// +// THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +// AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN +// ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION +// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + +var util = require('util/'); +var hasOwn = Object.prototype.hasOwnProperty; +var pSlice = Array.prototype.slice; +var functionsHaveNames = (function () { + return function foo() {}.name === 'foo'; +}()); +function pToString (obj) { + return Object.prototype.toString.call(obj); +} +function isView(arrbuf) { + if (isBuffer(arrbuf)) { + return false; + } + if (typeof global.ArrayBuffer !== 'function') { + return false; + } + if (typeof ArrayBuffer.isView === 'function') { + return ArrayBuffer.isView(arrbuf); + } + if (!arrbuf) { + return false; + } + if (arrbuf instanceof DataView) { + return true; + } + if (arrbuf.buffer && arrbuf.buffer instanceof ArrayBuffer) { + return true; + } + return false; +} +// 1. The assert module provides functions that throw +// AssertionError's when particular conditions are not met. The +// assert module must conform to the following interface. + +var assert = module.exports = ok; + +// 2. The AssertionError is defined in assert. +// new assert.AssertionError({ message: message, +// actual: actual, +// expected: expected }) + +var regex = /\s*function\s+([^\(\s]*)\s*/; +// based on https://github.com/ljharb/function.prototype.name/blob/adeeeec8bfcc6068b187d7d9fb3d5bb1d3a30899/implementation.js +function getName(func) { + if (!util.isFunction(func)) { + return; + } + if (functionsHaveNames) { + return func.name; + } + var str = func.toString(); + var match = str.match(regex); + return match && match[1]; +} +assert.AssertionError = function AssertionError(options) { + this.name = 'AssertionError'; + this.actual = options.actual; + this.expected = options.expected; + this.operator = options.operator; + if (options.message) { + this.message = options.message; + this.generatedMessage = false; + } else { + this.message = getMessage(this); + this.generatedMessage = true; + } + var stackStartFunction = options.stackStartFunction || fail; + if (Error.captureStackTrace) { + Error.captureStackTrace(this, stackStartFunction); + } else { + // non v8 browsers so we can have a stacktrace + var err = new Error(); + if (err.stack) { + var out = err.stack; + + // try to strip useless frames + var fn_name = getName(stackStartFunction); + var idx = out.indexOf('\n' + fn_name); + if (idx >= 0) { + // once we have located the function frame + // we need to strip out everything before it (and its line) + var next_line = out.indexOf('\n', idx + 1); + out = out.substring(next_line + 1); + } + + this.stack = out; + } + } +}; + +// assert.AssertionError instanceof Error +util.inherits(assert.AssertionError, Error); + +function truncate(s, n) { + if (typeof s === 'string') { + return s.length < n ? s : s.slice(0, n); + } else { + return s; + } +} +function inspect(something) { + if (functionsHaveNames || !util.isFunction(something)) { + return util.inspect(something); + } + var rawname = getName(something); + var name = rawname ? ': ' + rawname : ''; + return '[Function' + name + ']'; +} +function getMessage(self) { + return truncate(inspect(self.actual), 128) + ' ' + + self.operator + ' ' + + truncate(inspect(self.expected), 128); +} + +// At present only the three keys mentioned above are used and +// understood by the spec. Implementations or sub modules can pass +// other keys to the AssertionError's constructor - they will be +// ignored. + +// 3. All of the following functions must throw an AssertionError +// when a corresponding condition is not met, with a message that +// may be undefined if not provided. All assertion methods provide +// both the actual and expected values to the assertion error for +// display purposes. + +function fail(actual, expected, message, operator, stackStartFunction) { + throw new assert.AssertionError({ + message: message, + actual: actual, + expected: expected, + operator: operator, + stackStartFunction: stackStartFunction + }); +} + +// EXTENSION! allows for well behaved errors defined elsewhere. +assert.fail = fail; + +// 4. Pure assertion tests whether a value is truthy, as determined +// by !!guard. +// assert.ok(guard, message_opt); +// This statement is equivalent to assert.equal(true, !!guard, +// message_opt);. To test strictly for the value true, use +// assert.strictEqual(true, guard, message_opt);. + +function ok(value, message) { + if (!value) fail(value, true, message, '==', assert.ok); +} +assert.ok = ok; + +// 5. The equality assertion tests shallow, coercive equality with +// ==. +// assert.equal(actual, expected, message_opt); + +assert.equal = function equal(actual, expected, message) { + if (actual != expected) fail(actual, expected, message, '==', assert.equal); +}; + +// 6. The non-equality assertion tests for whether two objects are not equal +// with != assert.notEqual(actual, expected, message_opt); + +assert.notEqual = function notEqual(actual, expected, message) { + if (actual == expected) { + fail(actual, expected, message, '!=', assert.notEqual); + } +}; + +// 7. The equivalence assertion tests a deep equality relation. +// assert.deepEqual(actual, expected, message_opt); + +assert.deepEqual = function deepEqual(actual, expected, message) { + if (!_deepEqual(actual, expected, false)) { + fail(actual, expected, message, 'deepEqual', assert.deepEqual); + } +}; + +assert.deepStrictEqual = function deepStrictEqual(actual, expected, message) { + if (!_deepEqual(actual, expected, true)) { + fail(actual, expected, message, 'deepStrictEqual', assert.deepStrictEqual); + } +}; + +function _deepEqual(actual, expected, strict, memos) { + // 7.1. All identical values are equivalent, as determined by ===. + if (actual === expected) { + return true; + } else if (isBuffer(actual) && isBuffer(expected)) { + return compare(actual, expected) === 0; + + // 7.2. If the expected value is a Date object, the actual value is + // equivalent if it is also a Date object that refers to the same time. + } else if (util.isDate(actual) && util.isDate(expected)) { + return actual.getTime() === expected.getTime(); + + // 7.3 If the expected value is a RegExp object, the actual value is + // equivalent if it is also a RegExp object with the same source and + // properties (`global`, `multiline`, `lastIndex`, `ignoreCase`). + } else if (util.isRegExp(actual) && util.isRegExp(expected)) { + return actual.source === expected.source && + actual.global === expected.global && + actual.multiline === expected.multiline && + actual.lastIndex === expected.lastIndex && + actual.ignoreCase === expected.ignoreCase; + + // 7.4. Other pairs that do not both pass typeof value == 'object', + // equivalence is determined by ==. + } else if ((actual === null || typeof actual !== 'object') && + (expected === null || typeof expected !== 'object')) { + return strict ? actual === expected : actual == expected; + + // If both values are instances of typed arrays, wrap their underlying + // ArrayBuffers in a Buffer each to increase performance + // This optimization requires the arrays to have the same type as checked by + // Object.prototype.toString (aka pToString). Never perform binary + // comparisons for Float*Arrays, though, since e.g. +0 === -0 but their + // bit patterns are not identical. + } else if (isView(actual) && isView(expected) && + pToString(actual) === pToString(expected) && + !(actual instanceof Float32Array || + actual instanceof Float64Array)) { + return compare(new Uint8Array(actual.buffer), + new Uint8Array(expected.buffer)) === 0; + + // 7.5 For all other Object pairs, including Array objects, equivalence is + // determined by having the same number of owned properties (as verified + // with Object.prototype.hasOwnProperty.call), the same set of keys + // (although not necessarily the same order), equivalent values for every + // corresponding key, and an identical 'prototype' property. Note: this + // accounts for both named and indexed properties on Arrays. + } else if (isBuffer(actual) !== isBuffer(expected)) { + return false; + } else { + memos = memos || {actual: [], expected: []}; + + var actualIndex = memos.actual.indexOf(actual); + if (actualIndex !== -1) { + if (actualIndex === memos.expected.indexOf(expected)) { + return true; + } + } + + memos.actual.push(actual); + memos.expected.push(expected); + + return objEquiv(actual, expected, strict, memos); + } +} + +function isArguments(object) { + return Object.prototype.toString.call(object) == '[object Arguments]'; +} + +function objEquiv(a, b, strict, actualVisitedObjects) { + if (a === null || a === undefined || b === null || b === undefined) + return false; + // if one is a primitive, the other must be same + if (util.isPrimitive(a) || util.isPrimitive(b)) + return a === b; + if (strict && Object.getPrototypeOf(a) !== Object.getPrototypeOf(b)) + return false; + var aIsArgs = isArguments(a); + var bIsArgs = isArguments(b); + if ((aIsArgs && !bIsArgs) || (!aIsArgs && bIsArgs)) + return false; + if (aIsArgs) { + a = pSlice.call(a); + b = pSlice.call(b); + return _deepEqual(a, b, strict); + } + var ka = objectKeys(a); + var kb = objectKeys(b); + var key, i; + // having the same number of owned properties (keys incorporates + // hasOwnProperty) + if (ka.length !== kb.length) + return false; + //the same set of keys (although not necessarily the same order), + ka.sort(); + kb.sort(); + //~~~cheap key test + for (i = ka.length - 1; i >= 0; i--) { + if (ka[i] !== kb[i]) + return false; + } + //equivalent values for every corresponding key, and + //~~~possibly expensive deep test + for (i = ka.length - 1; i >= 0; i--) { + key = ka[i]; + if (!_deepEqual(a[key], b[key], strict, actualVisitedObjects)) + return false; + } + return true; +} + +// 8. The non-equivalence assertion tests for any deep inequality. +// assert.notDeepEqual(actual, expected, message_opt); + +assert.notDeepEqual = function notDeepEqual(actual, expected, message) { + if (_deepEqual(actual, expected, false)) { + fail(actual, expected, message, 'notDeepEqual', assert.notDeepEqual); + } +}; + +assert.notDeepStrictEqual = notDeepStrictEqual; +function notDeepStrictEqual(actual, expected, message) { + if (_deepEqual(actual, expected, true)) { + fail(actual, expected, message, 'notDeepStrictEqual', notDeepStrictEqual); + } +} + + +// 9. The strict equality assertion tests strict equality, as determined by ===. +// assert.strictEqual(actual, expected, message_opt); + +assert.strictEqual = function strictEqual(actual, expected, message) { + if (actual !== expected) { + fail(actual, expected, message, '===', assert.strictEqual); + } +}; + +// 10. The strict non-equality assertion tests for strict inequality, as +// determined by !==. assert.notStrictEqual(actual, expected, message_opt); + +assert.notStrictEqual = function notStrictEqual(actual, expected, message) { + if (actual === expected) { + fail(actual, expected, message, '!==', assert.notStrictEqual); + } +}; + +function expectedException(actual, expected) { + if (!actual || !expected) { + return false; + } + + if (Object.prototype.toString.call(expected) == '[object RegExp]') { + return expected.test(actual); + } + + try { + if (actual instanceof expected) { + return true; + } + } catch (e) { + // Ignore. The instanceof check doesn't work for arrow functions. + } + + if (Error.isPrototypeOf(expected)) { + return false; + } + + return expected.call({}, actual) === true; +} + +function _tryBlock(block) { + var error; + try { + block(); + } catch (e) { + error = e; + } + return error; +} + +function _throws(shouldThrow, block, expected, message) { + var actual; + + if (typeof block !== 'function') { + throw new TypeError('"block" argument must be a function'); + } + + if (typeof expected === 'string') { + message = expected; + expected = null; + } + + actual = _tryBlock(block); + + message = (expected && expected.name ? ' (' + expected.name + ').' : '.') + + (message ? ' ' + message : '.'); + + if (shouldThrow && !actual) { + fail(actual, expected, 'Missing expected exception' + message); + } + + var userProvidedMessage = typeof message === 'string'; + var isUnwantedException = !shouldThrow && util.isError(actual); + var isUnexpectedException = !shouldThrow && actual && !expected; + + if ((isUnwantedException && + userProvidedMessage && + expectedException(actual, expected)) || + isUnexpectedException) { + fail(actual, expected, 'Got unwanted exception' + message); + } + + if ((shouldThrow && actual && expected && + !expectedException(actual, expected)) || (!shouldThrow && actual)) { + throw actual; + } +} + +// 11. Expected to throw an error: +// assert.throws(block, Error_opt, message_opt); + +assert.throws = function(block, /*optional*/error, /*optional*/message) { + _throws(true, block, error, message); +}; + +// EXTENSION! This is annoying to write outside this module. +assert.doesNotThrow = function(block, /*optional*/error, /*optional*/message) { + _throws(false, block, error, message); +}; + +assert.ifError = function(err) { if (err) throw err; }; + +var objectKeys = Object.keys || function (obj) { + var keys = []; + for (var key in obj) { + if (hasOwn.call(obj, key)) keys.push(key); + } + return keys; +}; + +},{"util/":36}],30:[function(require,module,exports){ +/** + # lazy-seq + + > Lazy sequences + + [![Build Status](https://secure.travis-ci.org/phadej/lazy-seq.svg?branch=master)](http://travis-ci.org/phadej/lazy-seq) + [![NPM version](https://badge.fury.io/js/lazy-seq.svg)](http://badge.fury.io/js/lazy-seq) + [![Dependency Status](https://david-dm.org/phadej/lazy-seq.svg)](https://david-dm.org/phadej/lazy-seq) + [![devDependency Status](https://david-dm.org/phadej/lazy-seq/dev-status.svg)](https://david-dm.org/phadej/lazy-seq#info=devDependencies) + [![Code Climate](https://img.shields.io/codeclimate/github/phadej/lazy-seq.svg)](https://codeclimate.com/github/phadej/lazy-seq) + + ## Lazy? + + The list structure could be defined as + + ```hs + data Seq a = Nil | Cons a (Seq a) + ``` + + The `Cons` constuctor takes two arguments, so there are four different laziness variants: + + ```hs + Cons (Strict a) (Strict (Seq a)) -- 1. fully strict + Cons (Lazy a) (Strict (Seq a)) -- 2. lazy values + Cons (Strict a) (Lazy (Seq a)) -- 3. lazy structure + Cons (Lazy a) (Lazy (Seq a)) -- 4. fully lazy + ``` + + This module implements the third variant: lazy structure, but strict values. + + ## Example + + ```js + var ones = lazyseq.cons(1, function () { return ones; }); + console.log(ones === ones.tail()); // true! + ``` + + ## Why? + + This package is originally made to optimise shrink operations in [jsverify](http://jsverify.github.io/), a property-based testing library. + + ## API +*/ + +"use strict"; + +var assert = require("assert"); + +/** + - *nil : Seq a* — Empty sequence. + + - *cons : (head : a, tail : Array a | Seq a | () → Array a | () → Seq a) → Seq a* : Cons a value to the front of a sequence (list or thunk). +*/ +var nil = {}; + +/** + - *.isNil : Boolean* — Constant time check, whether the sequence is empty. +*/ +nil.isNil = true; + +/** + - *.toString : () → String* — String representation. Doesn't force the tail. +*/ +nil.toString = function () { + return "nil"; +}; + +/** + - *.length : () → Nat* — Return the length of the sequene. Forces the structure. +*/ +nil.length = function () { + return 0; +}; + +/** + - *.toArray : () → Array a* — Convert the sequence to JavaScript array. +*/ +nil.toArray = function nilToArray() { + return []; +}; + +/** + - *.fold : (z : b, f : (a, () → b) → b) → b* — Fold from right. + + ```hs + fold nil x f = x + fold (cons h t) x f = f x (fold t x f) + ``` +*/ +nil.fold = function nilFold(x /*, f */) { + return x; +}; + +/** + - *.head : () → a* — Extract the first element of a sequence, which must be non-empty. +*/ +nil.head = function nilHead() { + throw new Error("nil.head"); +}; + +/** + - *.tail : () → Seq a* — Return the tail of the sequence. + + ```hs + tail nil = nil + tail (cons h t) = t + ``` +*/ +nil.tail = function nilTail() { + return nil; +}; + +/** + - *.nth : (n : Nat) → a* — Return nth value of the sequence. +*/ +nil.nth = function nilNth(n) { + assert(typeof n === "number"); + throw new Error("Can't get " + n + "th value of the nil"); +}; + +/** + - *.take : (n : Nat) → Seq a* — Take `n` first elements of the sequence. +*/ +nil.take = function (n) { + assert(typeof n === "number"); + return nil; +}; + +/** + - *.drop : (n : Nat) → Seq a* — Drop `n` first elements of the sequence. +*/ +nil.drop = function (n) { + assert(typeof n === "number"); + return nil; +}; + +/** + - *.map : (f : a → b) : Seq b* — The sequence obtained by applying `f` to each element of the original sequence. +*/ +nil.map = function (f) { + assert(typeof f === "function"); + return nil; +}; + +/** + - *.append : (ys : Seq a | Array a) : Seq a* — Append `ys` sequence. +*/ +nil.append = function (seq) { + if (typeof seq === "function") { + seq = seq(); + } + + if (Array.isArray(seq)) { + /* eslint-disable no-use-before-define */ + return fromArray(seq); + /* eslint-enable no-use-before-define */ + } else { + return seq; + } +}; + +/** + - *.filter : (p : a -> bool) : Seq a* — filter using `p` predicate. +*/ +nil.filter = function () { + return nil; +}; + +/** + - *.every : (p = identity: a -> b) : b | true — return first falsy value in the sequence, true otherwise. *N.B.* behaves slightly differently from `Array::every`. +*/ +nil.every = function () { + return true; +}; + +/** + - *.some : (p = identity: a -> b) : b | false — return first truthy value in the sequence, false otherwise. *N.B.* behaves slightly differently from `Array::some`. +*/ +nil.some = function () { + return false; +}; + +/** + - *.contains : (x : a) : bool — Returns `true` if `x` is in the sequence. +*/ +nil.contains = function () { + return false; +}; + +/** + - *.containsNot : (x : a) : bool — Returns `true` if `x` is not in the sequence. +*/ +nil.containsNot = function () { + return true; +}; + +// Default cons values are with strict semantics +function Cons(head, tail) { + this.headValue = head; + this.tailValue = tail; +} + +Cons.prototype.isNil = false; + +Cons.prototype.toString = function () { + return "Cons(" + this.headValue + ", " + this.tailValue + ")"; +}; + +Cons.prototype.length = function () { + return 1 + this.tail().length(); +}; + +Cons.prototype.toArray = function () { + var ptr = this; + var acc = []; + while (ptr !== nil) { + acc.push(ptr.headValue); + ptr = ptr.tail(); + } + return acc; +}; + +Cons.prototype.fold = function consFold(x, f) { + var self = this; + return f(this.headValue, function () { + return self.tail().fold(x, f); + }); +}; + +Cons.prototype.head = function consHead() { + return this.headValue; +}; + +Cons.prototype.tail = function consTail() { + return this.tailValue; +}; + +// But when cons is created, it's overloaded with lazy ones + +// Force tail to whnf. +function lazyConsForce() { + /* jshint validthis:true */ + var val = this.tailFn(); + /* eslint-disable no-use-before-define */ + this.tailValue = Array.isArray(val) ? fromArray(val) : val; + /* eslint-enable no-use-before-define */ + + delete this.tail; + delete this.force; + + return this; +} + +function lazyConsTail() { + /* jshint validthis:true */ + this.force(); + return this.tailValue; +} + +function delay(head, tail) { + assert(typeof tail === "function"); + + head.tailFn = tail; + head.tail = lazyConsTail; + + head.force = lazyConsForce; + return head; +} + +function cons(head, tail) { + if (typeof tail === "function") { + return delay(new Cons(head), tail); + } else if (Array.isArray(tail)) { + return delay(cons(head), function () { + /* eslint-disable no-use-before-define */ + return fromArray(tail); + /* eslint-enable no-use-before-define */ + }); + } else { + return new Cons(head, tail); + } +} + +// Rest of the functions. They might use cons + +Cons.prototype.nth = function consNth(n) { + assert(typeof n === "number"); + return n === 0 ? this.headValue : this.tail().nth(n - 1); +}; + +Cons.prototype.take = function consTake(n) { + assert(typeof n === "number"); + var that = this; + return n === 0 ? nil : cons(this.headValue, function () { + return that.tail().take(n - 1); + }); +}; + +Cons.prototype.drop = function consDrop(n) { + assert(typeof n === "number"); + return n === 0 ? this : this.tail().drop(n - 1); +}; + +Cons.prototype.map = function consMap(f) { + assert(typeof f === "function"); + var that = this; + return cons(f(that.headValue), function () { + return that.tail().map(f); + }); +}; + +Cons.prototype.append = function consAppend(seq) { + // Short circuit decidable: (++ []) ≡ id + if (seq === nil || (Array.isArray(seq) && seq.length === 0)) { + return this; + } + var that = this; + return cons(that.headValue, function () { + return that.tail().append(seq); + }); +}; + +Cons.prototype.filter = function consFilter(p) { + assert(typeof p === "function"); + var that = this; + if (p(that.headValue)) { + return cons(that.headValue, function () { + return that.tail().filter(p); + }); + } else { + return that.tail().filter(p); + } +}; + +Cons.prototype.every = function consEvery(p) { + p = p || function (x) { return x; }; + assert(typeof p === "function"); + var that = this; + var pHead = p(that.headValue); + if (!pHead) { + return pHead; + } else { + return that.tail().every(p); + } +}; + +Cons.prototype.some = function consSome(p) { + p = p || function (x) { return x; }; + assert(typeof p === "function"); + var that = this; + var pHead = p(that.headValue); + if (pHead) { + return pHead; + } else { + return that.tail().some(p); + } +}; + +Cons.prototype.contains = function consContains(x) { + var that = this; + if (x === that.headValue) { + return true; + } else { + return that.tail().contains(x); + } +}; + +Cons.prototype.containsNot = function consContainsNot(x) { + var that = this; + if (x === that.headValue) { + return false; + } else { + return that.tail().containsNot(x); + } +}; + +// Constructors +/** + - *fromArray: (arr : Array a) → Seq a* — Convert a JavaScript array into lazy sequence. +*/ +function fromArrayIter(arr, n) { + if (n < arr.length) { + return cons(arr[n], function () { + return fromArrayIter(arr, n + 1); + }); + } else { + return nil; + } +} + +function fromArray(arr) { + assert(Array.isArray(arr)); + return fromArrayIter(arr, 0); +} + +/** + - *singleton: (x : a) → Seq a* — Create a singleton sequence. +*/ +function singleton(x) { + return fromArray([x]); +} + +/** + - *append : (xs... : Array a | Seq a | () → Array a | () → Seq a) → Seq a* : Append one sequence-like to another. +*/ +function append() { + var acc = nil; + for (var i = 0; i < arguments.length; i++) { + acc = acc.append(arguments[i]); + } + return acc; +} + +/** + - *iterate : (x : a, f : a → a) → Seq a* — Create an infinite sequence of repeated applications of `f` to `x`: *x, f(x), f(f(x))…*. +*/ +function iterate(x, f) { + return cons(x, function () { + return iterate(f(x), f); + }); +} + +/** + - *fold : (seq : Seq a | Array a, z : b, f : (a, () → b) → b) : b* — polymorphic version of fold. Works with arrays too. +*/ +function listFold(list, z, f, n) { + if (n < list.length) { + return f(list[n], function () { + return listFold(list, z, f, n + 1); + }); + } else { + return z; + } +} + +function fold(list, z, f) { + if (Array.isArray(list)) { + return listFold(list, z, f, 0); + } else { + return list.fold(z, f); + } +} + +module.exports = { + nil: nil, + cons: cons, + append: append, + fromArray: fromArray, + singleton: singleton, + iterate: iterate, + fold: fold, +}; + +/// plain CHANGELOG.md +/// plain CONTRIBUTING.md + +},{"assert":29}],31:[function(require,module,exports){ +"use strict"; + +// Based on RC4 algorithm, as described in +// http://en.wikipedia.org/wiki/RC4 + +function isInteger(n) { + return parseInt(n, 10) === n; +} + +function createRC4(N) { + function identityPermutation() { + var s = new Array(N); + for (var i = 0; i < N; i++) { + s[i] = i; + } + return s; + } + + // :: string | array integer -> array integer + function seed(key) { + if (key === undefined) { + key = new Array(N); + for (var k = 0; k < N; k++) { + key[k] = Math.floor(Math.random() * N); + } + } else if (typeof key === "string") { + // to string + key = "" + key; + key = key.split("").map(function (c) { return c.charCodeAt(0) % N; }); + } else if (Array.isArray(key)) { + if (!key.every(function (v) { + return typeof v === "number" && v === (v | 0); + })) { + throw new TypeError("invalid seed key specified: not array of integers"); + } + } else { + throw new TypeError("invalid seed key specified"); + } + + var keylen = key.length; + + // resed state + var s = identityPermutation(); + + var j = 0; + for (var i = 0; i < N; i++) { + j = (j + s[i] + key[i % keylen]) % N; + var tmp = s[i]; + s[i] = s[j]; + s[j] = tmp; + } + + return s; + } + + /* eslint-disable no-shadow */ + function RC4(key) { + this.s = seed(key); + this.i = 0; + this.j = 0; + } + /* eslint-enable no-shadow */ + + RC4.prototype.randomNative = function () { + this.i = (this.i + 1) % N; + this.j = (this.j + this.s[this.i]) % N; + + var tmp = this.s[this.i]; + this.s[this.i] = this.s[this.j]; + this.s[this.j] = tmp; + + var k = this.s[(this.s[this.i] + this.s[this.j]) % N]; + + return k; + }; + + RC4.prototype.randomUInt32 = function () { + var a = this.randomByte(); + var b = this.randomByte(); + var c = this.randomByte(); + var d = this.randomByte(); + + return ((a * 256 + b) * 256 + c) * 256 + d; + }; + + RC4.prototype.randomFloat = function () { + return this.randomUInt32() / 0x100000000; + }; + + RC4.prototype.random = function () { + var a; + var b; + + if (arguments.length === 1) { + a = 0; + b = arguments[0]; + } else if (arguments.length === 2) { + a = arguments[0]; + b = arguments[1]; + } else { + throw new TypeError("random takes one or two integer arguments"); + } + + if (!isInteger(a) || !isInteger(b)) { + throw new TypeError("random takes one or two integer arguments"); + } + + return a + this.randomUInt32() % (b - a + 1); + }; + + RC4.prototype.currentState = function () { + return { + i: this.i, + j: this.j, + s: this.s.slice(), // copy + }; + }; + + RC4.prototype.setState = function (state) { + var s = state.s; + var i = state.i; + var j = state.j; + + /* eslint-disable yoda */ + if (!(i === (i | 0) && 0 <= i && i < N)) { + throw new Error("state.i should be integer [0, " + (N - 1) + "]"); + } + + if (!(j === (j | 0) && 0 <= j && j < N)) { + throw new Error("state.j should be integer [0, " + (N - 1) + "]"); + } + /* eslint-enable yoda */ + + // check length + if (!Array.isArray(s) || s.length !== N) { + throw new Error("state should be array of length " + N); + } + + // check that all params are there + for (var k = 0; k < N; k++) { + if (s.indexOf(k) === -1) { + throw new Error("state should be permutation of 0.." + (N - 1) + ": " + k + " is missing"); + } + } + + this.i = i; + this.j = j; + this.s = s.slice(); // assign copy + }; + + return RC4; +} + +var RC4 = createRC4(256); +RC4.prototype.randomByte = RC4.prototype.randomNative; + +var RC4small = createRC4(16); +RC4small.prototype.randomByte = function () { + var a = this.randomNative(); + var b = this.randomNative(); + + return a * 16 + b; +}; + +var ordA = "a".charCodeAt(0); +var ord0 = "0".charCodeAt(0); + +function toHex(n) { + return n < 10 ? String.fromCharCode(ord0 + n) : String.fromCharCode(ordA + n - 10); +} + +function fromHex(c) { + return parseInt(c, 16); +} + +RC4small.prototype.currentStateString = function () { + var state = this.currentState(); + + var i = toHex(state.i); + var j = toHex(state.j); + + var res = i + j + state.s.map(toHex).join(""); + return res; +}; + +RC4small.prototype.setStateString = function (stateString) { + if (!stateString.match(/^[0-9a-f]{18}$/)) { + throw new TypeError("RC4small stateString should be 18 hex character string"); + } + + var i = fromHex(stateString[0]); + var j = fromHex(stateString[1]); + var s = stateString.split("").slice(2).map(fromHex); + + this.setState({ + i: i, + j: j, + s: s, + }); +}; + +RC4.RC4small = RC4small; + +module.exports = RC4; + +},{}],32:[function(require,module,exports){ +"use strict"; + +/** + +# trampa + +Trampolines, to emulate tail-call recursion. + +[![Build Status](https://secure.travis-ci.org/phadej/trampa.svg?branch=master)](http://travis-ci.org/phadej/trampa) +[![NPM version](https://badge.fury.io/js/trampa.svg)](http://badge.fury.io/js/trampa) +[![Dependency Status](https://david-dm.org/trampa/trampa.svg)](https://david-dm.org/trampa/trampa) +[![devDependency Status](https://david-dm.org/trampa/trampa/dev-status.svg)](https://david-dm.org/trampa/trampa#info=devDependencies) +[![Code Climate](https://img.shields.io/codeclimate/github/phadej/trampa.svg)](https://codeclimate.com/github/phadej/trampa) + +## Synopsis + +```js +var trampa = require("trampa"); + +function loop(n, acc) { + return n === 0 ? trampa.wrap(acc) : trampa.lazy(function () { + return loop(n - 1, acc + 1); + }); +} + +loop(123456789, 0).run(); // doesn't cause stack overflow! +``` + +## API + +*/ + +// loosely based on https://apocalisp.wordpress.com/2011/10/26/tail-call-elimination-in-scala-monads/ + +var assert = require("assert"); + +function Done(x) { + this.x = x; +} + +function Cont(tramp, cont) { + assert(typeof cont === "function"); + this.tramp = tramp; + this.cont = cont; +} + +/** +- `isTrampoline(t: obj): bool` — Returns, whether `t` is a trampolined object. +*/ +function isTrampoline(t) { + return t instanceof Done || t instanceof Cont; +} + +/** +- `wrap(t: Trampoline a | a): Trampoline a` — Wrap `t` into trampoline, if it's not already one. +*/ +function wrap(t) { + return isTrampoline(t) ? t : new Done(t); +} + +/** +- `lazy(t : () -> Trampoline a | a)` — Wrap lazy computation into trampoline. Useful when constructing computations. +*/ +function lazy(computation) { + assert(typeof computation === "function", "lazy: computation should be function"); + return wrap().jump(computation); +} + +/** +- `Trampoline.jump(f : a -> b | Trampoline b)` — *map* or *flatmap* trampoline computation. Like `.then` for promises. +*/ +Done.prototype.jump = function (f) { + return new Cont(this, function (x) { + return wrap(f(x)); + }); +}; + +Cont.prototype.jump = Done.prototype.jump; + +function execute(curr, params) { + params = params || {}; + var debug = params.debug || false; + var log = params.log || console.log; + var stack = []; + + while (true) { // eslint-disable-line no-constant-condition + if (debug) { + log("trampoline execute: stack size " + stack.length); + } + + if (curr instanceof Done) { + if (stack.length === 0) { + return curr.x; + } else { + curr = stack[stack.length - 1](curr.x); + stack.pop(); + } + } else { + assert(curr instanceof Cont); + stack.push(curr.cont); + curr = curr.tramp; + } + } +} + +/** +- `Trampoline.run(): a` — Run the trampoline synchronously resulting a value. +*/ +Done.prototype.run = Cont.prototype.run = function (params) { + return execute(this, params); +}; + +module.exports = { + isTrampoline: isTrampoline, + wrap: wrap, + lazy: lazy, +}; + +/** +## Changelog + +- **1.0.0** — *2015-07-14* — Initial release +*/ + +},{"assert":29}],33:[function(require,module,exports){ +/** + # typify type parser + + > Type signature parser for typify + + [![Build Status](https://secure.travis-ci.org/phadej/typify-parser.svg?branch=master)](http://travis-ci.org/phadej/typify-parser) + [![NPM version](https://badge.fury.io/js/typify-parser.svg)](http://badge.fury.io/js/typify-parser) + [![Dependency Status](https://david-dm.org/phadej/typify-parser.svg)](https://david-dm.org/phadej/typify-parser) + [![devDependency Status](https://david-dm.org/phadej/typify-parser/dev-status.svg)](https://david-dm.org/phadej/typify-parser#info=devDependencies) + [![Code Climate](https://img.shields.io/codeclimate/github/phadej/typify-parser.svg)](https://codeclimate.com/github/phadej/typify-parser) + + Turns `(foo, bar 42) -> quux` into + ```js + { + "type": "function", + "arg": { + "type": "product", + "args": [ + { + "type": "ident", + "value": "foo" + }, + { + "type": "application", + "callee": { + "type": "ident", + "value": "bar" + }, + "args": [ + { + "type": "number", + "value": 42 + } + ] + } + ] + }, + "result": { + "type": "ident", + "value": "quux" + } + } + ``` + + ## Synopsis + + ```js + var parser = require("typify-parser"); + + // Example from above + var t = parser("(foo, bar 42) -> quux"); + + // Free vars + p.freeVars(t); // ['bar', 'foo', 'quux'] + p.freeVars(p("rec list -> () | a & list")) // ['a'] + ``` +*/ +"use strict"; + +function unescapeString(str) { + return str.replace(/\\(?:'|"|\\|n|x[0-9a-fA-F]{2})/g, function (match) { + switch (match[1]) { + case "'": return "'"; + case "\"": return "\""; + case "\\": return "\\"; + case "n": return "\n"; + case "x": return String.fromCharCode(parseInt(match.substr(2), 16)); + } + }); +} + +function lex(input) { + // Unicode + // top: 22a4 + // bottom: 22a5 + // and: 2227 + // or: 2228 + // times: \u00d7 + // to: 2192 + // ellipsis: 2026 + // blackboard 1: d835 dfd9 + var m = input.match(/^([ \t\r\n]+|[\u22a4\u22a5\u2227\u2228\u00d7\u2192\u2026]|\ud835\udfd9|_\|_|\*|\(\)|"(?:[^"\\]|\\[\\'"n]|\\x[0-9a-fA-F]{2})*"|'(?:[^'\\]|\\[\\'"n]|\\x[0-9a-fA-F]{2})*'|[0-9a-zA-Z_\$@]+|,|->|:|;|&|\||\.\.\.|\(|\)|\[|\]|\{|\}|\?)*$/); + if (m === null) { + throw new SyntaxError("Cannot lex type signature"); + } + m = input.match(/([ \t\r\n]+|[\u22a4\u22a5\u2227\u2228\u00d7\u2192\u2026]|\ud835\udfd9|_\|_|\*|\(\)|"(?:[^"\\]|\\[\\'"n]|\\x[0-9a-fA-F]{2})*"|'(?:[^'\\]|\\[\\'"n]|\\x[0-9a-fA-F]{2})*'|[0-9a-zA-Z_\$@]+|,|->|:|;|&|\||\.\.\.|\(|\)|\[|\]|\{|\}|\?)/g); + + return m + .map(function (token) { + switch (token) { + case "_|_": return { type: "false" }; + case "\u22a5": return { type: "false" }; + case "*": return { type: "true" }; + case "\u22a4": return { type: "true" }; + case "()": return { type: "unit" }; + case "\ud835\udfd9": return { type: "unit" }; + case "true": return { type: "bool", value: true }; + case "false": return { type: "bool", value: false }; + case "rec": return { type: "rec" }; + case "&": return { type: "&" }; + case "\u2227": return { type: "&" }; + case "|": return { type: "|" }; + case "\u2228": return { type: "|" }; + case ",": return { type: "," }; + case "\u00d7": return { type: "," }; + case ";": return { type: ";" }; + case ":": return { type: ":" }; + case "(": return { type: "(" }; + case ")": return { type: ")" }; + case "[": return { type: "[" }; + case "]": return { type: "]" }; + case "{": return { type: "{" }; + case "}": return { type: "}" }; + case "?": return { type: "?" }; + case "->": return { type: "->" }; + case "\u2192": return { type: "->" }; + case "...": return { type: "..." }; + case "\u2026": return { type: "..." }; + } + + // Whitespace + if (token.match(/^[ \r\r\n]+$/)) { + return null; + } + + if (token.match(/^[0-9]+/)) { + return { type: "number", value: parseInt(token, 10) }; + } + + if (token[0] === "'" || token[0] === "\"") { + token = token.slice(1, -1); + return { type: "string", value: unescapeString(token) }; + } + + return { type: "ident", value: token }; + }) + .filter(function (token) { + return token !== null; + }); +} + +function makePunctParser(type) { + return function (state) { + if (state.pos >= state.len) { + throw new SyntaxError("Expecting identifier, end-of-input found"); + } + + var token = state.tokens[state.pos]; + if (token.type !== type) { + throw new SyntaxError("Expecting '" + type + "', found: " + token.type); + } + state.pos += 1; + + return type; + }; +} + +var colonParser = makePunctParser(":"); +var openCurlyParser = makePunctParser("{"); +var closeCurlyParser = makePunctParser("}"); +var semicolonParser = makePunctParser(";"); +var openParenParser = makePunctParser("("); +var closeParenParser = makePunctParser(")"); +var openBracketParser = makePunctParser("["); +var closeBracketParser = makePunctParser("]"); +var recKeywordParser = makePunctParser("rec"); +var arrowParser = makePunctParser("->"); + +function nameParser(state) { + if (state.pos >= state.len) { + throw new SyntaxError("Expecting identifier, end-of-input found"); + } + + var token = state.tokens[state.pos]; + if (token.type !== "ident") { + throw new SyntaxError("Expecting 'ident', found: " + token.type); + } + state.pos += 1; + + return token.value; +} + +function recursiveParser(state) { + recKeywordParser(state); + var name = nameParser(state); + arrowParser(state); + var value = typeParser(state); // eslint-disable-line no-use-before-define + return { + type: "recursive", + name: name, + arg: value, + }; +} + +function recordParser(state) { + openCurlyParser(state); + + var token = state.tokens[state.pos]; + if (token && token.type === "}") { + closeCurlyParser(state); + return { type: "record", fields: {} }; + } + + var fields = {}; + + while (true) { // eslint-disable-line no-constant-condition + // read + var name = nameParser(state); + colonParser(state); + var value = typeParser(state); // eslint-disable-line no-use-before-define + + // assign to fields + fields[name] = value; + + // ending token + token = state.tokens[state.pos]; + + // break if } + if (token && token.type === "}") { + closeCurlyParser(state); + break; + } else if (token && token.type === ";") { + semicolonParser(state); + } else { + throw new SyntaxError("Expecting '}' or ';', found: " + token.type); + } + } + + return { type: "record", fields: fields }; +} + +function postfix(parser, postfixToken, constructor) { + return function (state) { + var arg = parser(state); + + var token = state.tokens[state.pos]; + if (token && token.type === postfixToken) { + state.pos += 1; + return { + type: constructor, + arg: arg, + }; + } else { + return arg; + } + }; +} + +// this ties the knot +var optionalParser = postfix(terminalParser, "?", "optional"); // eslint-disable-line no-use-before-define + +function applicationParser(state) { + var rator = optionalParser(state); + var rands = []; + + while (true) { // eslint-disable-line no-constant-condition + var pos = state.pos; + // XXX: we shouldn't use exceptions for this + try { + var arg = optionalParser(state); + rands.push(arg); + } catch (err) { + state.pos = pos; + break; + } + } + + if (rands.length === 0) { + return rator; + } else { + return { + type: "application", + callee: rator, + args: rands, + }; + } +} + +function separatedBy(parser, separator, constructor) { + return function (state) { + var list = [parser(state)]; + while (true) { // eslint-disable-line no-constant-condition + // separator + var token = state.tokens[state.pos]; + if (token && token.type === separator) { + state.pos += 1; + } else { + break; + } + + // right argument + list.push(parser(state)); + } + + if (list.length === 1) { + return list[0]; + } else { + return { + type: constructor, + args: list, + }; + } + }; +} + +var conjunctionParser = separatedBy(applicationParser, "&", "conjunction"); +var disjunctionParser = separatedBy(conjunctionParser, "|", "disjunction"); + +// TODO: combine with optional +var variadicParser = postfix(disjunctionParser, "...", "variadic"); + +function namedParser(state) { + var token1 = state.tokens[state.pos]; + var token2 = state.tokens[state.pos + 1]; + if (token1 && token2 && token1.type === "ident" && token2.type === ":") { + state.pos += 2; + var arg = namedParser(state); + return { + type: "named", + name: token1.value, + arg: arg, + }; + } else { + return variadicParser(state); + } +} + +var productParser = separatedBy(namedParser, ",", "product"); + +function functionParser(state) { + var v = productParser(state); + + var token = state.tokens[state.pos]; + if (token && token.type === "->") { + state.pos += 1; + var result = functionParser(state); + return { + type: "function", + arg: v, + result: result, + }; + } else { + return v; + } +} + +function typeParser(state) { + return functionParser(state); +} + +function parenthesesParser(state) { + openParenParser(state); + var type = typeParser(state); + closeParenParser(state); + return type; +} + +function bracketParser(state) { + openBracketParser(state); + var type = typeParser(state); + closeBracketParser(state); + return { + type: "brackets", + arg: type, + }; +} + +function terminalParser(state) { + if (state.pos >= state.len) { + throw new SyntaxError("Expecting terminal, end-of-input found"); + } + + var token = state.tokens[state.pos]; + switch (token.type) { + case "false": + case "true": + case "unit": + case "string": + case "number": + case "bool": + case "ident": + state.pos += 1; + return token; + case "{": + return recordParser(state); + case "(": + return parenthesesParser(state); + case "[": + return bracketParser(state); + case "rec": + return recursiveParser(state); + default: + throw new SyntaxError("Expecting terminal, " + token.type + " found"); + } +} + +function parse(input) { + // console.log(input); + var tokens = lex(input); + // console.log(tokens); + var state = { + pos: 0, + len: tokens.length, + tokens: tokens, + }; + + var res = typeParser(state); + // console.log(state); + if (state.pos !== state.len) { + throw new SyntaxError("expecting end-of-input, " + tokens[state.pos].type + " found"); + } + return res; +} + +function recordFreeVars(fields) { + var res = []; + for (var k in fields) { + var t = fields[k]; + res = res.concat(freeVarsImpl(t)); // eslint-disable-line no-use-before-define + } + return res; +} + +function concatFreeVars(ts) { + var res = []; + for (var i = 0; i < ts.length; i++) { + var t = ts[i]; + res = res.concat(freeVarsImpl(t)); // eslint-disable-line no-use-before-define + } + return res; +} + +function freeVarsImpl(t) { + switch (t.type) { + case "false": + case "true": + case "unit": + case "string": + case "number": + case "bool": + return []; + case "ident": return [t.value]; + case "record": return recordFreeVars(t.fields); + case "named": return freeVarsImpl(t.arg); + case "conjunction": return concatFreeVars(t.args); + case "disjunction": return concatFreeVars(t.args); + case "product": return concatFreeVars(t.args); + case "recursive": return freeVarsImpl(t.arg).filter(function (n) { + return n !== t.name; + }); + case "optional": return freeVarsImpl(t.arg); + case "brackets": return freeVarsImpl(t.arg); + case "variadic": return freeVarsImpl(t.arg); + case "application": return freeVarsImpl(t.callee).concat(concatFreeVars(t.args)); + case "function": return freeVarsImpl(t.arg).concat(freeVarsImpl(t.result)); + //default: throw new Error("Unknown type " + t.type); + } +} + +function uniq(arr) { + var res = []; + for (var i = 0; i < arr.length; i++) { + var x = arr[i]; + if (res.indexOf(x) === -1) { + res.push(x); + } + } + return res; +} + +function freeVars(t) { + var fvs = freeVarsImpl(t); + fvs.sort(); + return uniq(fvs); +} + +parse.freeVars = freeVars; + +module.exports = parse; + +},{}],34:[function(require,module,exports){ +if (typeof Object.create === 'function') { + // implementation from standard node.js 'util' module + module.exports = function inherits(ctor, superCtor) { + ctor.super_ = superCtor + ctor.prototype = Object.create(superCtor.prototype, { + constructor: { + value: ctor, + enumerable: false, + writable: true, + configurable: true + } + }); + }; +} else { + // old school shim for old browsers + module.exports = function inherits(ctor, superCtor) { + ctor.super_ = superCtor + var TempCtor = function () {} + TempCtor.prototype = superCtor.prototype + ctor.prototype = new TempCtor() + ctor.prototype.constructor = ctor + } +} + +},{}],35:[function(require,module,exports){ +module.exports = function isBuffer(arg) { + return arg && typeof arg === 'object' + && typeof arg.copy === 'function' + && typeof arg.fill === 'function' + && typeof arg.readUInt8 === 'function'; +} +},{}],36:[function(require,module,exports){ +// Copyright Joyent, Inc. and other Node contributors. +// +// Permission is hereby granted, free of charge, to any person obtaining a +// copy of this software and associated documentation files (the +// "Software"), to deal in the Software without restriction, including +// without limitation the rights to use, copy, modify, merge, publish, +// distribute, sublicense, and/or sell copies of the Software, and to permit +// persons to whom the Software is furnished to do so, subject to the +// following conditions: +// +// The above copyright notice and this permission notice shall be included +// in all copies or substantial portions of the Software. +// +// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS +// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF +// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN +// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, +// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR +// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE +// USE OR OTHER DEALINGS IN THE SOFTWARE. + +var formatRegExp = /%[sdj%]/g; +exports.format = function(f) { + if (!isString(f)) { + var objects = []; + for (var i = 0; i < arguments.length; i++) { + objects.push(inspect(arguments[i])); + } + return objects.join(' '); + } + + var i = 1; + var args = arguments; + var len = args.length; + var str = String(f).replace(formatRegExp, function(x) { + if (x === '%%') return '%'; + if (i >= len) return x; + switch (x) { + case '%s': return String(args[i++]); + case '%d': return Number(args[i++]); + case '%j': + try { + return JSON.stringify(args[i++]); + } catch (_) { + return '[Circular]'; + } + default: + return x; + } + }); + for (var x = args[i]; i < len; x = args[++i]) { + if (isNull(x) || !isObject(x)) { + str += ' ' + x; + } else { + str += ' ' + inspect(x); + } + } + return str; +}; + + +// Mark that a method should not be used. +// Returns a modified function which warns once by default. +// If --no-deprecation is set, then it is a no-op. +exports.deprecate = function(fn, msg) { + // Allow for deprecating things in the process of starting up. + if (isUndefined(global.process)) { + return function() { + return exports.deprecate(fn, msg).apply(this, arguments); + }; + } + + if (process.noDeprecation === true) { + return fn; + } + + var warned = false; + function deprecated() { + if (!warned) { + if (process.throwDeprecation) { + throw new Error(msg); + } else if (process.traceDeprecation) { + console.trace(msg); + } else { + console.error(msg); + } + warned = true; + } + return fn.apply(this, arguments); + } + + return deprecated; +}; + + +var debugs = {}; +var debugEnviron; +exports.debuglog = function(set) { + if (isUndefined(debugEnviron)) + debugEnviron = process.env.NODE_DEBUG || ''; + set = set.toUpperCase(); + if (!debugs[set]) { + if (new RegExp('\\b' + set + '\\b', 'i').test(debugEnviron)) { + var pid = process.pid; + debugs[set] = function() { + var msg = exports.format.apply(exports, arguments); + console.error('%s %d: %s', set, pid, msg); + }; + } else { + debugs[set] = function() {}; + } + } + return debugs[set]; +}; + + +/** + * Echos the value of a value. Trys to print the value out + * in the best way possible given the different types. + * + * @param {Object} obj The object to print out. + * @param {Object} opts Optional options object that alters the output. + */ +/* legacy: obj, showHidden, depth, colors*/ +function inspect(obj, opts) { + // default options + var ctx = { + seen: [], + stylize: stylizeNoColor + }; + // legacy... + if (arguments.length >= 3) ctx.depth = arguments[2]; + if (arguments.length >= 4) ctx.colors = arguments[3]; + if (isBoolean(opts)) { + // legacy... + ctx.showHidden = opts; + } else if (opts) { + // got an "options" object + exports._extend(ctx, opts); + } + // set default options + if (isUndefined(ctx.showHidden)) ctx.showHidden = false; + if (isUndefined(ctx.depth)) ctx.depth = 2; + if (isUndefined(ctx.colors)) ctx.colors = false; + if (isUndefined(ctx.customInspect)) ctx.customInspect = true; + if (ctx.colors) ctx.stylize = stylizeWithColor; + return formatValue(ctx, obj, ctx.depth); +} +exports.inspect = inspect; + + +// http://en.wikipedia.org/wiki/ANSI_escape_code#graphics +inspect.colors = { + 'bold' : [1, 22], + 'italic' : [3, 23], + 'underline' : [4, 24], + 'inverse' : [7, 27], + 'white' : [37, 39], + 'grey' : [90, 39], + 'black' : [30, 39], + 'blue' : [34, 39], + 'cyan' : [36, 39], + 'green' : [32, 39], + 'magenta' : [35, 39], + 'red' : [31, 39], + 'yellow' : [33, 39] +}; + +// Don't use 'blue' not visible on cmd.exe +inspect.styles = { + 'special': 'cyan', + 'number': 'yellow', + 'boolean': 'yellow', + 'undefined': 'grey', + 'null': 'bold', + 'string': 'green', + 'date': 'magenta', + // "name": intentionally not styling + 'regexp': 'red' +}; + + +function stylizeWithColor(str, styleType) { + var style = inspect.styles[styleType]; + + if (style) { + return '\u001b[' + inspect.colors[style][0] + 'm' + str + + '\u001b[' + inspect.colors[style][1] + 'm'; + } else { + return str; + } +} + + +function stylizeNoColor(str, styleType) { + return str; +} + + +function arrayToHash(array) { + var hash = {}; + + array.forEach(function(val, idx) { + hash[val] = true; + }); + + return hash; +} + + +function formatValue(ctx, value, recurseTimes) { + // Provide a hook for user-specified inspect functions. + // Check that value is an object with an inspect function on it + if (ctx.customInspect && + value && + isFunction(value.inspect) && + // Filter out the util module, it's inspect function is special + value.inspect !== exports.inspect && + // Also filter out any prototype objects using the circular check. + !(value.constructor && value.constructor.prototype === value)) { + var ret = value.inspect(recurseTimes, ctx); + if (!isString(ret)) { + ret = formatValue(ctx, ret, recurseTimes); + } + return ret; + } + + // Primitive types cannot have properties + var primitive = formatPrimitive(ctx, value); + if (primitive) { + return primitive; + } + + // Look up the keys of the object. + var keys = Object.keys(value); + var visibleKeys = arrayToHash(keys); + + if (ctx.showHidden) { + keys = Object.getOwnPropertyNames(value); + } + + // IE doesn't make error fields non-enumerable + // http://msdn.microsoft.com/en-us/library/ie/dww52sbt(v=vs.94).aspx + if (isError(value) + && (keys.indexOf('message') >= 0 || keys.indexOf('description') >= 0)) { + return formatError(value); + } + + // Some type of object without properties can be shortcutted. + if (keys.length === 0) { + if (isFunction(value)) { + var name = value.name ? ': ' + value.name : ''; + return ctx.stylize('[Function' + name + ']', 'special'); + } + if (isRegExp(value)) { + return ctx.stylize(RegExp.prototype.toString.call(value), 'regexp'); + } + if (isDate(value)) { + return ctx.stylize(Date.prototype.toString.call(value), 'date'); + } + if (isError(value)) { + return formatError(value); + } + } + + var base = '', array = false, braces = ['{', '}']; + + // Make Array say that they are Array + if (isArray(value)) { + array = true; + braces = ['[', ']']; + } + + // Make functions say that they are functions + if (isFunction(value)) { + var n = value.name ? ': ' + value.name : ''; + base = ' [Function' + n + ']'; + } + + // Make RegExps say that they are RegExps + if (isRegExp(value)) { + base = ' ' + RegExp.prototype.toString.call(value); + } + + // Make dates with properties first say the date + if (isDate(value)) { + base = ' ' + Date.prototype.toUTCString.call(value); + } + + // Make error with message first say the error + if (isError(value)) { + base = ' ' + formatError(value); + } + + if (keys.length === 0 && (!array || value.length == 0)) { + return braces[0] + base + braces[1]; + } + + if (recurseTimes < 0) { + if (isRegExp(value)) { + return ctx.stylize(RegExp.prototype.toString.call(value), 'regexp'); + } else { + return ctx.stylize('[Object]', 'special'); + } + } + + ctx.seen.push(value); + + var output; + if (array) { + output = formatArray(ctx, value, recurseTimes, visibleKeys, keys); + } else { + output = keys.map(function(key) { + return formatProperty(ctx, value, recurseTimes, visibleKeys, key, array); + }); + } + + ctx.seen.pop(); + + return reduceToSingleString(output, base, braces); +} + + +function formatPrimitive(ctx, value) { + if (isUndefined(value)) + return ctx.stylize('undefined', 'undefined'); + if (isString(value)) { + var simple = '\'' + JSON.stringify(value).replace(/^"|"$/g, '') + .replace(/'/g, "\\'") + .replace(/\\"/g, '"') + '\''; + return ctx.stylize(simple, 'string'); + } + if (isNumber(value)) + return ctx.stylize('' + value, 'number'); + if (isBoolean(value)) + return ctx.stylize('' + value, 'boolean'); + // For some reason typeof null is "object", so special case here. + if (isNull(value)) + return ctx.stylize('null', 'null'); +} + + +function formatError(value) { + return '[' + Error.prototype.toString.call(value) + ']'; +} + + +function formatArray(ctx, value, recurseTimes, visibleKeys, keys) { + var output = []; + for (var i = 0, l = value.length; i < l; ++i) { + if (hasOwnProperty(value, String(i))) { + output.push(formatProperty(ctx, value, recurseTimes, visibleKeys, + String(i), true)); + } else { + output.push(''); + } + } + keys.forEach(function(key) { + if (!key.match(/^\d+$/)) { + output.push(formatProperty(ctx, value, recurseTimes, visibleKeys, + key, true)); + } + }); + return output; +} + + +function formatProperty(ctx, value, recurseTimes, visibleKeys, key, array) { + var name, str, desc; + desc = Object.getOwnPropertyDescriptor(value, key) || { value: value[key] }; + if (desc.get) { + if (desc.set) { + str = ctx.stylize('[Getter/Setter]', 'special'); + } else { + str = ctx.stylize('[Getter]', 'special'); + } + } else { + if (desc.set) { + str = ctx.stylize('[Setter]', 'special'); + } + } + if (!hasOwnProperty(visibleKeys, key)) { + name = '[' + key + ']'; + } + if (!str) { + if (ctx.seen.indexOf(desc.value) < 0) { + if (isNull(recurseTimes)) { + str = formatValue(ctx, desc.value, null); + } else { + str = formatValue(ctx, desc.value, recurseTimes - 1); + } + if (str.indexOf('\n') > -1) { + if (array) { + str = str.split('\n').map(function(line) { + return ' ' + line; + }).join('\n').substr(2); + } else { + str = '\n' + str.split('\n').map(function(line) { + return ' ' + line; + }).join('\n'); + } + } + } else { + str = ctx.stylize('[Circular]', 'special'); + } + } + if (isUndefined(name)) { + if (array && key.match(/^\d+$/)) { + return str; + } + name = JSON.stringify('' + key); + if (name.match(/^"([a-zA-Z_][a-zA-Z_0-9]*)"$/)) { + name = name.substr(1, name.length - 2); + name = ctx.stylize(name, 'name'); + } else { + name = name.replace(/'/g, "\\'") + .replace(/\\"/g, '"') + .replace(/(^"|"$)/g, "'"); + name = ctx.stylize(name, 'string'); + } + } + + return name + ': ' + str; +} + + +function reduceToSingleString(output, base, braces) { + var numLinesEst = 0; + var length = output.reduce(function(prev, cur) { + numLinesEst++; + if (cur.indexOf('\n') >= 0) numLinesEst++; + return prev + cur.replace(/\u001b\[\d\d?m/g, '').length + 1; + }, 0); + + if (length > 60) { + return braces[0] + + (base === '' ? '' : base + '\n ') + + ' ' + + output.join(',\n ') + + ' ' + + braces[1]; + } + + return braces[0] + base + ' ' + output.join(', ') + ' ' + braces[1]; +} + + +// NOTE: These type checking functions intentionally don't use `instanceof` +// because it is fragile and can be easily faked with `Object.create()`. +function isArray(ar) { + return Array.isArray(ar); +} +exports.isArray = isArray; + +function isBoolean(arg) { + return typeof arg === 'boolean'; +} +exports.isBoolean = isBoolean; + +function isNull(arg) { + return arg === null; +} +exports.isNull = isNull; + +function isNullOrUndefined(arg) { + return arg == null; +} +exports.isNullOrUndefined = isNullOrUndefined; + +function isNumber(arg) { + return typeof arg === 'number'; +} +exports.isNumber = isNumber; + +function isString(arg) { + return typeof arg === 'string'; +} +exports.isString = isString; + +function isSymbol(arg) { + return typeof arg === 'symbol'; +} +exports.isSymbol = isSymbol; + +function isUndefined(arg) { + return arg === void 0; +} +exports.isUndefined = isUndefined; + +function isRegExp(re) { + return isObject(re) && objectToString(re) === '[object RegExp]'; +} +exports.isRegExp = isRegExp; + +function isObject(arg) { + return typeof arg === 'object' && arg !== null; +} +exports.isObject = isObject; + +function isDate(d) { + return isObject(d) && objectToString(d) === '[object Date]'; +} +exports.isDate = isDate; + +function isError(e) { + return isObject(e) && + (objectToString(e) === '[object Error]' || e instanceof Error); +} +exports.isError = isError; + +function isFunction(arg) { + return typeof arg === 'function'; +} +exports.isFunction = isFunction; + +function isPrimitive(arg) { + return arg === null || + typeof arg === 'boolean' || + typeof arg === 'number' || + typeof arg === 'string' || + typeof arg === 'symbol' || // ES6 symbol + typeof arg === 'undefined'; +} +exports.isPrimitive = isPrimitive; + +exports.isBuffer = require('./support/isBuffer'); + +function objectToString(o) { + return Object.prototype.toString.call(o); +} + + +function pad(n) { + return n < 10 ? '0' + n.toString(10) : n.toString(10); +} + + +var months = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', + 'Oct', 'Nov', 'Dec']; + +// 26 Feb 16:19:34 +function timestamp() { + var d = new Date(); + var time = [pad(d.getHours()), + pad(d.getMinutes()), + pad(d.getSeconds())].join(':'); + return [d.getDate(), months[d.getMonth()], time].join(' '); +} + + +// log is just a thin wrapper to console.log that prepends a timestamp +exports.log = function() { + console.log('%s - %s', timestamp(), exports.format.apply(exports, arguments)); +}; + + +/** + * Inherit the prototype methods from one constructor into another. + * + * The Function.prototype.inherits from lang.js rewritten as a standalone + * function (not on Function.prototype). NOTE: If this file is to be loaded + * during bootstrapping this function needs to be rewritten using some native + * functions as prototype setup using normal JavaScript does not work as + * expected during bootstrapping (see mirror.js in r114903). + * + * @param {function} ctor Constructor function which needs to inherit the + * prototype. + * @param {function} superCtor Constructor function to inherit prototype from. + */ +exports.inherits = require('inherits'); + +exports._extend = function(origin, add) { + // Don't do anything if add isn't an object + if (!add || !isObject(add)) return origin; + + var keys = Object.keys(add); + var i = keys.length; + while (i--) { + origin[keys[i]] = add[keys[i]]; + } + return origin; +}; + +function hasOwnProperty(obj, prop) { + return Object.prototype.hasOwnProperty.call(obj, prop); +} + +},{"./support/isBuffer":35,"inherits":34}]},{},[15])(15) +}); + diff --git a/hw2/claudio_maggioni/resources/lodash.js b/hw2/claudio_maggioni/resources/lodash.js new file mode 100644 index 0000000..b39ddce --- /dev/null +++ b/hw2/claudio_maggioni/resources/lodash.js @@ -0,0 +1,17084 @@ +/** + * @license + * Lodash + * Copyright JS Foundation and other contributors + * Released under MIT license + * Based on Underscore.js 1.8.3 + * Copyright Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors + */ +;(function() { + + /** Used as a safe reference for `undefined` in pre-ES5 environments. */ + var undefined; + + /** Used as the semantic version number. */ + var VERSION = '4.17.4'; + + /** Used as the size to enable large array optimizations. */ + var LARGE_ARRAY_SIZE = 200; + + /** Error message constants. */ + var CORE_ERROR_TEXT = 'Unsupported core-js use. Try https://npms.io/search?q=ponyfill.', + FUNC_ERROR_TEXT = 'Expected a function'; + + /** Used to stand-in for `undefined` hash values. */ + var HASH_UNDEFINED = '__lodash_hash_undefined__'; + + /** Used as the maximum memoize cache size. */ + var MAX_MEMOIZE_SIZE = 500; + + /** Used as the internal argument placeholder. */ + var PLACEHOLDER = '__lodash_placeholder__'; + + /** Used to compose bitmasks for cloning. */ + var CLONE_DEEP_FLAG = 1, + CLONE_FLAT_FLAG = 2, + CLONE_SYMBOLS_FLAG = 4; + + /** Used to compose bitmasks for value comparisons. */ + var COMPARE_PARTIAL_FLAG = 1, + COMPARE_UNORDERED_FLAG = 2; + + /** Used to compose bitmasks for function metadata. */ + var WRAP_BIND_FLAG = 1, + WRAP_BIND_KEY_FLAG = 2, + WRAP_CURRY_BOUND_FLAG = 4, + WRAP_CURRY_FLAG = 8, + WRAP_CURRY_RIGHT_FLAG = 16, + WRAP_PARTIAL_FLAG = 32, + WRAP_PARTIAL_RIGHT_FLAG = 64, + WRAP_ARY_FLAG = 128, + WRAP_REARG_FLAG = 256, + WRAP_FLIP_FLAG = 512; + + /** Used as default options for `_.truncate`. */ + var DEFAULT_TRUNC_LENGTH = 30, + DEFAULT_TRUNC_OMISSION = '...'; + + /** Used to detect hot functions by number of calls within a span of milliseconds. */ + var HOT_COUNT = 800, + HOT_SPAN = 16; + + /** Used to indicate the type of lazy iteratees. */ + var LAZY_FILTER_FLAG = 1, + LAZY_MAP_FLAG = 2, + LAZY_WHILE_FLAG = 3; + + /** Used as references for various `Number` constants. */ + var INFINITY = 1 / 0, + MAX_SAFE_INTEGER = 9007199254740991, + MAX_INTEGER = 1.7976931348623157e+308, + NAN = 0 / 0; + + /** Used as references for the maximum length and index of an array. */ + var MAX_ARRAY_LENGTH = 4294967295, + MAX_ARRAY_INDEX = MAX_ARRAY_LENGTH - 1, + HALF_MAX_ARRAY_LENGTH = MAX_ARRAY_LENGTH >>> 1; + + /** Used to associate wrap methods with their bit flags. */ + var wrapFlags = [ + ['ary', WRAP_ARY_FLAG], + ['bind', WRAP_BIND_FLAG], + ['bindKey', WRAP_BIND_KEY_FLAG], + ['curry', WRAP_CURRY_FLAG], + ['curryRight', WRAP_CURRY_RIGHT_FLAG], + ['flip', WRAP_FLIP_FLAG], + ['partial', WRAP_PARTIAL_FLAG], + ['partialRight', WRAP_PARTIAL_RIGHT_FLAG], + ['rearg', WRAP_REARG_FLAG] + ]; + + /** `Object#toString` result references. */ + var argsTag = '[object Arguments]', + arrayTag = '[object Array]', + asyncTag = '[object AsyncFunction]', + boolTag = '[object Boolean]', + dateTag = '[object Date]', + domExcTag = '[object DOMException]', + errorTag = '[object Error]', + funcTag = '[object Function]', + genTag = '[object GeneratorFunction]', + mapTag = '[object Map]', + numberTag = '[object Number]', + nullTag = '[object Null]', + objectTag = '[object Object]', + promiseTag = '[object Promise]', + proxyTag = '[object Proxy]', + regexpTag = '[object RegExp]', + setTag = '[object Set]', + stringTag = '[object String]', + symbolTag = '[object Symbol]', + undefinedTag = '[object Undefined]', + weakMapTag = '[object WeakMap]', + weakSetTag = '[object WeakSet]'; + + var arrayBufferTag = '[object ArrayBuffer]', + dataViewTag = '[object DataView]', + float32Tag = '[object Float32Array]', + float64Tag = '[object Float64Array]', + int8Tag = '[object Int8Array]', + int16Tag = '[object Int16Array]', + int32Tag = '[object Int32Array]', + uint8Tag = '[object Uint8Array]', + uint8ClampedTag = '[object Uint8ClampedArray]', + uint16Tag = '[object Uint16Array]', + uint32Tag = '[object Uint32Array]'; + + /** Used to match empty string literals in compiled template source. */ + var reEmptyStringLeading = /\b__p \+= '';/g, + reEmptyStringMiddle = /\b(__p \+=) '' \+/g, + reEmptyStringTrailing = /(__e\(.*?\)|\b__t\)) \+\n'';/g; + + /** Used to match HTML entities and HTML characters. */ + var reEscapedHtml = /&(?:amp|lt|gt|quot|#39);/g, + reUnescapedHtml = /[&<>"']/g, + reHasEscapedHtml = RegExp(reEscapedHtml.source), + reHasUnescapedHtml = RegExp(reUnescapedHtml.source); + + /** Used to match template delimiters. */ + var reEscape = /<%-([\s\S]+?)%>/g, + reEvaluate = /<%([\s\S]+?)%>/g, + reInterpolate = /<%=([\s\S]+?)%>/g; + + /** Used to match property names within property paths. */ + var reIsDeepProp = /\.|\[(?:[^[\]]*|(["'])(?:(?!\1)[^\\]|\\.)*?\1)\]/, + reIsPlainProp = /^\w*$/, + reLeadingDot = /^\./, + rePropName = /[^.[\]]+|\[(?:(-?\d+(?:\.\d+)?)|(["'])((?:(?!\2)[^\\]|\\.)*?)\2)\]|(?=(?:\.|\[\])(?:\.|\[\]|$))/g; + + /** + * Used to match `RegExp` + * [syntax characters](http://ecma-international.org/ecma-262/7.0/#sec-patterns). + */ + var reRegExpChar = /[\\^$.*+?()[\]{}|]/g, + reHasRegExpChar = RegExp(reRegExpChar.source); + + /** Used to match leading and trailing whitespace. */ + var reTrim = /^\s+|\s+$/g, + reTrimStart = /^\s+/, + reTrimEnd = /\s+$/; + + /** Used to match wrap detail comments. */ + var reWrapComment = /\{(?:\n\/\* \[wrapped with .+\] \*\/)?\n?/, + reWrapDetails = /\{\n\/\* \[wrapped with (.+)\] \*/, + reSplitDetails = /,? & /; + + /** Used to match words composed of alphanumeric characters. */ + var reAsciiWord = /[^\x00-\x2f\x3a-\x40\x5b-\x60\x7b-\x7f]+/g; + + /** Used to match backslashes in property paths. */ + var reEscapeChar = /\\(\\)?/g; + + /** + * Used to match + * [ES template delimiters](http://ecma-international.org/ecma-262/7.0/#sec-template-literal-lexical-components). + */ + var reEsTemplate = /\$\{([^\\}]*(?:\\.[^\\}]*)*)\}/g; + + /** Used to match `RegExp` flags from their coerced string values. */ + var reFlags = /\w*$/; + + /** Used to detect bad signed hexadecimal string values. */ + var reIsBadHex = /^[-+]0x[0-9a-f]+$/i; + + /** Used to detect binary string values. */ + var reIsBinary = /^0b[01]+$/i; + + /** Used to detect host constructors (Safari). */ + var reIsHostCtor = /^\[object .+?Constructor\]$/; + + /** Used to detect octal string values. */ + var reIsOctal = /^0o[0-7]+$/i; + + /** Used to detect unsigned integer values. */ + var reIsUint = /^(?:0|[1-9]\d*)$/; + + /** Used to match Latin Unicode letters (excluding mathematical operators). */ + var reLatin = /[\xc0-\xd6\xd8-\xf6\xf8-\xff\u0100-\u017f]/g; + + /** Used to ensure capturing order of template delimiters. */ + var reNoMatch = /($^)/; + + /** Used to match unescaped characters in compiled string literals. */ + var reUnescapedString = /['\n\r\u2028\u2029\\]/g; + + /** Used to compose unicode character classes. */ + var rsAstralRange = '\\ud800-\\udfff', + rsComboMarksRange = '\\u0300-\\u036f', + reComboHalfMarksRange = '\\ufe20-\\ufe2f', + rsComboSymbolsRange = '\\u20d0-\\u20ff', + rsComboRange = rsComboMarksRange + reComboHalfMarksRange + rsComboSymbolsRange, + rsDingbatRange = '\\u2700-\\u27bf', + rsLowerRange = 'a-z\\xdf-\\xf6\\xf8-\\xff', + rsMathOpRange = '\\xac\\xb1\\xd7\\xf7', + rsNonCharRange = '\\x00-\\x2f\\x3a-\\x40\\x5b-\\x60\\x7b-\\xbf', + rsPunctuationRange = '\\u2000-\\u206f', + rsSpaceRange = ' \\t\\x0b\\f\\xa0\\ufeff\\n\\r\\u2028\\u2029\\u1680\\u180e\\u2000\\u2001\\u2002\\u2003\\u2004\\u2005\\u2006\\u2007\\u2008\\u2009\\u200a\\u202f\\u205f\\u3000', + rsUpperRange = 'A-Z\\xc0-\\xd6\\xd8-\\xde', + rsVarRange = '\\ufe0e\\ufe0f', + rsBreakRange = rsMathOpRange + rsNonCharRange + rsPunctuationRange + rsSpaceRange; + + /** Used to compose unicode capture groups. */ + var rsApos = "['\u2019]", + rsAstral = '[' + rsAstralRange + ']', + rsBreak = '[' + rsBreakRange + ']', + rsCombo = '[' + rsComboRange + ']', + rsDigits = '\\d+', + rsDingbat = '[' + rsDingbatRange + ']', + rsLower = '[' + rsLowerRange + ']', + rsMisc = '[^' + rsAstralRange + rsBreakRange + rsDigits + rsDingbatRange + rsLowerRange + rsUpperRange + ']', + rsFitz = '\\ud83c[\\udffb-\\udfff]', + rsModifier = '(?:' + rsCombo + '|' + rsFitz + ')', + rsNonAstral = '[^' + rsAstralRange + ']', + rsRegional = '(?:\\ud83c[\\udde6-\\uddff]){2}', + rsSurrPair = '[\\ud800-\\udbff][\\udc00-\\udfff]', + rsUpper = '[' + rsUpperRange + ']', + rsZWJ = '\\u200d'; + + /** Used to compose unicode regexes. */ + var rsMiscLower = '(?:' + rsLower + '|' + rsMisc + ')', + rsMiscUpper = '(?:' + rsUpper + '|' + rsMisc + ')', + rsOptContrLower = '(?:' + rsApos + '(?:d|ll|m|re|s|t|ve))?', + rsOptContrUpper = '(?:' + rsApos + '(?:D|LL|M|RE|S|T|VE))?', + reOptMod = rsModifier + '?', + rsOptVar = '[' + rsVarRange + ']?', + rsOptJoin = '(?:' + rsZWJ + '(?:' + [rsNonAstral, rsRegional, rsSurrPair].join('|') + ')' + rsOptVar + reOptMod + ')*', + rsOrdLower = '\\d*(?:(?:1st|2nd|3rd|(?![123])\\dth)\\b)', + rsOrdUpper = '\\d*(?:(?:1ST|2ND|3RD|(?![123])\\dTH)\\b)', + rsSeq = rsOptVar + reOptMod + rsOptJoin, + rsEmoji = '(?:' + [rsDingbat, rsRegional, rsSurrPair].join('|') + ')' + rsSeq, + rsSymbol = '(?:' + [rsNonAstral + rsCombo + '?', rsCombo, rsRegional, rsSurrPair, rsAstral].join('|') + ')'; + + /** Used to match apostrophes. */ + var reApos = RegExp(rsApos, 'g'); + + /** + * Used to match [combining diacritical marks](https://en.wikipedia.org/wiki/Combining_Diacritical_Marks) and + * [combining diacritical marks for symbols](https://en.wikipedia.org/wiki/Combining_Diacritical_Marks_for_Symbols). + */ + var reComboMark = RegExp(rsCombo, 'g'); + + /** Used to match [string symbols](https://mathiasbynens.be/notes/javascript-unicode). */ + var reUnicode = RegExp(rsFitz + '(?=' + rsFitz + ')|' + rsSymbol + rsSeq, 'g'); + + /** Used to match complex or compound words. */ + var reUnicodeWord = RegExp([ + rsUpper + '?' + rsLower + '+' + rsOptContrLower + '(?=' + [rsBreak, rsUpper, '$'].join('|') + ')', + rsMiscUpper + '+' + rsOptContrUpper + '(?=' + [rsBreak, rsUpper + rsMiscLower, '$'].join('|') + ')', + rsUpper + '?' + rsMiscLower + '+' + rsOptContrLower, + rsUpper + '+' + rsOptContrUpper, + rsOrdUpper, + rsOrdLower, + rsDigits, + rsEmoji + ].join('|'), 'g'); + + /** Used to detect strings with [zero-width joiners or code points from the astral planes](http://eev.ee/blog/2015/09/12/dark-corners-of-unicode/). */ + var reHasUnicode = RegExp('[' + rsZWJ + rsAstralRange + rsComboRange + rsVarRange + ']'); + + /** Used to detect strings that need a more robust regexp to match words. */ + var reHasUnicodeWord = /[a-z][A-Z]|[A-Z]{2,}[a-z]|[0-9][a-zA-Z]|[a-zA-Z][0-9]|[^a-zA-Z0-9 ]/; + + /** Used to assign default `context` object properties. */ + var contextProps = [ + 'Array', 'Buffer', 'DataView', 'Date', 'Error', 'Float32Array', 'Float64Array', + 'Function', 'Int8Array', 'Int16Array', 'Int32Array', 'Map', 'Math', 'Object', + 'Promise', 'RegExp', 'Set', 'String', 'Symbol', 'TypeError', 'Uint8Array', + 'Uint8ClampedArray', 'Uint16Array', 'Uint32Array', 'WeakMap', + '_', 'clearTimeout', 'isFinite', 'parseInt', 'setTimeout' + ]; + + /** Used to make template sourceURLs easier to identify. */ + var templateCounter = -1; + + /** Used to identify `toStringTag` values of typed arrays. */ + var typedArrayTags = {}; + typedArrayTags[float32Tag] = typedArrayTags[float64Tag] = + typedArrayTags[int8Tag] = typedArrayTags[int16Tag] = + typedArrayTags[int32Tag] = typedArrayTags[uint8Tag] = + typedArrayTags[uint8ClampedTag] = typedArrayTags[uint16Tag] = + typedArrayTags[uint32Tag] = true; + typedArrayTags[argsTag] = typedArrayTags[arrayTag] = + typedArrayTags[arrayBufferTag] = typedArrayTags[boolTag] = + typedArrayTags[dataViewTag] = typedArrayTags[dateTag] = + typedArrayTags[errorTag] = typedArrayTags[funcTag] = + typedArrayTags[mapTag] = typedArrayTags[numberTag] = + typedArrayTags[objectTag] = typedArrayTags[regexpTag] = + typedArrayTags[setTag] = typedArrayTags[stringTag] = + typedArrayTags[weakMapTag] = false; + + /** Used to identify `toStringTag` values supported by `_.clone`. */ + var cloneableTags = {}; + cloneableTags[argsTag] = cloneableTags[arrayTag] = + cloneableTags[arrayBufferTag] = cloneableTags[dataViewTag] = + cloneableTags[boolTag] = cloneableTags[dateTag] = + cloneableTags[float32Tag] = cloneableTags[float64Tag] = + cloneableTags[int8Tag] = cloneableTags[int16Tag] = + cloneableTags[int32Tag] = cloneableTags[mapTag] = + cloneableTags[numberTag] = cloneableTags[objectTag] = + cloneableTags[regexpTag] = cloneableTags[setTag] = + cloneableTags[stringTag] = cloneableTags[symbolTag] = + cloneableTags[uint8Tag] = cloneableTags[uint8ClampedTag] = + cloneableTags[uint16Tag] = cloneableTags[uint32Tag] = true; + cloneableTags[errorTag] = cloneableTags[funcTag] = + cloneableTags[weakMapTag] = false; + + /** Used to map Latin Unicode letters to basic Latin letters. */ + var deburredLetters = { + // Latin-1 Supplement block. + '\xc0': 'A', '\xc1': 'A', '\xc2': 'A', '\xc3': 'A', '\xc4': 'A', '\xc5': 'A', + '\xe0': 'a', '\xe1': 'a', '\xe2': 'a', '\xe3': 'a', '\xe4': 'a', '\xe5': 'a', + '\xc7': 'C', '\xe7': 'c', + '\xd0': 'D', '\xf0': 'd', + '\xc8': 'E', '\xc9': 'E', '\xca': 'E', '\xcb': 'E', + '\xe8': 'e', '\xe9': 'e', '\xea': 'e', '\xeb': 'e', + '\xcc': 'I', '\xcd': 'I', '\xce': 'I', '\xcf': 'I', + '\xec': 'i', '\xed': 'i', '\xee': 'i', '\xef': 'i', + '\xd1': 'N', '\xf1': 'n', + '\xd2': 'O', '\xd3': 'O', '\xd4': 'O', '\xd5': 'O', '\xd6': 'O', '\xd8': 'O', + '\xf2': 'o', '\xf3': 'o', '\xf4': 'o', '\xf5': 'o', '\xf6': 'o', '\xf8': 'o', + '\xd9': 'U', '\xda': 'U', '\xdb': 'U', '\xdc': 'U', + '\xf9': 'u', '\xfa': 'u', '\xfb': 'u', '\xfc': 'u', + '\xdd': 'Y', '\xfd': 'y', '\xff': 'y', + '\xc6': 'Ae', '\xe6': 'ae', + '\xde': 'Th', '\xfe': 'th', + '\xdf': 'ss', + // Latin Extended-A block. + '\u0100': 'A', '\u0102': 'A', '\u0104': 'A', + '\u0101': 'a', '\u0103': 'a', '\u0105': 'a', + '\u0106': 'C', '\u0108': 'C', '\u010a': 'C', '\u010c': 'C', + '\u0107': 'c', '\u0109': 'c', '\u010b': 'c', '\u010d': 'c', + '\u010e': 'D', '\u0110': 'D', '\u010f': 'd', '\u0111': 'd', + '\u0112': 'E', '\u0114': 'E', '\u0116': 'E', '\u0118': 'E', '\u011a': 'E', + '\u0113': 'e', '\u0115': 'e', '\u0117': 'e', '\u0119': 'e', '\u011b': 'e', + '\u011c': 'G', '\u011e': 'G', '\u0120': 'G', '\u0122': 'G', + '\u011d': 'g', '\u011f': 'g', '\u0121': 'g', '\u0123': 'g', + '\u0124': 'H', '\u0126': 'H', '\u0125': 'h', '\u0127': 'h', + '\u0128': 'I', '\u012a': 'I', '\u012c': 'I', '\u012e': 'I', '\u0130': 'I', + '\u0129': 'i', '\u012b': 'i', '\u012d': 'i', '\u012f': 'i', '\u0131': 'i', + '\u0134': 'J', '\u0135': 'j', + '\u0136': 'K', '\u0137': 'k', '\u0138': 'k', + '\u0139': 'L', '\u013b': 'L', '\u013d': 'L', '\u013f': 'L', '\u0141': 'L', + '\u013a': 'l', '\u013c': 'l', '\u013e': 'l', '\u0140': 'l', '\u0142': 'l', + '\u0143': 'N', '\u0145': 'N', '\u0147': 'N', '\u014a': 'N', + '\u0144': 'n', '\u0146': 'n', '\u0148': 'n', '\u014b': 'n', + '\u014c': 'O', '\u014e': 'O', '\u0150': 'O', + '\u014d': 'o', '\u014f': 'o', '\u0151': 'o', + '\u0154': 'R', '\u0156': 'R', '\u0158': 'R', + '\u0155': 'r', '\u0157': 'r', '\u0159': 'r', + '\u015a': 'S', '\u015c': 'S', '\u015e': 'S', '\u0160': 'S', + '\u015b': 's', '\u015d': 's', '\u015f': 's', '\u0161': 's', + '\u0162': 'T', '\u0164': 'T', '\u0166': 'T', + '\u0163': 't', '\u0165': 't', '\u0167': 't', + '\u0168': 'U', '\u016a': 'U', '\u016c': 'U', '\u016e': 'U', '\u0170': 'U', '\u0172': 'U', + '\u0169': 'u', '\u016b': 'u', '\u016d': 'u', '\u016f': 'u', '\u0171': 'u', '\u0173': 'u', + '\u0174': 'W', '\u0175': 'w', + '\u0176': 'Y', '\u0177': 'y', '\u0178': 'Y', + '\u0179': 'Z', '\u017b': 'Z', '\u017d': 'Z', + '\u017a': 'z', '\u017c': 'z', '\u017e': 'z', + '\u0132': 'IJ', '\u0133': 'ij', + '\u0152': 'Oe', '\u0153': 'oe', + '\u0149': "'n", '\u017f': 's' + }; + + /** Used to map characters to HTML entities. */ + var htmlEscapes = { + '&': '&', + '<': '<', + '>': '>', + '"': '"', + "'": ''' + }; + + /** Used to map HTML entities to characters. */ + var htmlUnescapes = { + '&': '&', + '<': '<', + '>': '>', + '"': '"', + ''': "'" + }; + + /** Used to escape characters for inclusion in compiled string literals. */ + var stringEscapes = { + '\\': '\\', + "'": "'", + '\n': 'n', + '\r': 'r', + '\u2028': 'u2028', + '\u2029': 'u2029' + }; + + /** Built-in method references without a dependency on `root`. */ + var freeParseFloat = parseFloat, + freeParseInt = parseInt; + + /** Detect free variable `global` from Node.js. */ + var freeGlobal = typeof global == 'object' && global && global.Object === Object && global; + + /** Detect free variable `self`. */ + var freeSelf = typeof self == 'object' && self && self.Object === Object && self; + + /** Used as a reference to the global object. */ + var root = freeGlobal || freeSelf || Function('return this')(); + + /** Detect free variable `exports`. */ + var freeExports = typeof exports == 'object' && exports && !exports.nodeType && exports; + + /** Detect free variable `module`. */ + var freeModule = freeExports && typeof module == 'object' && module && !module.nodeType && module; + + /** Detect the popular CommonJS extension `module.exports`. */ + var moduleExports = freeModule && freeModule.exports === freeExports; + + /** Detect free variable `process` from Node.js. */ + var freeProcess = moduleExports && freeGlobal.process; + + /** Used to access faster Node.js helpers. */ + var nodeUtil = (function() { + try { + return freeProcess && freeProcess.binding && freeProcess.binding('util'); + } catch (e) {} + }()); + + /* Node.js helper references. */ + var nodeIsArrayBuffer = nodeUtil && nodeUtil.isArrayBuffer, + nodeIsDate = nodeUtil && nodeUtil.isDate, + nodeIsMap = nodeUtil && nodeUtil.isMap, + nodeIsRegExp = nodeUtil && nodeUtil.isRegExp, + nodeIsSet = nodeUtil && nodeUtil.isSet, + nodeIsTypedArray = nodeUtil && nodeUtil.isTypedArray; + + /*--------------------------------------------------------------------------*/ + + /** + * Adds the key-value `pair` to `map`. + * + * @private + * @param {Object} map The map to modify. + * @param {Array} pair The key-value pair to add. + * @returns {Object} Returns `map`. + */ + function addMapEntry(map, pair) { + // Don't return `map.set` because it's not chainable in IE 11. + map.set(pair[0], pair[1]); + return map; + } + + /** + * Adds `value` to `set`. + * + * @private + * @param {Object} set The set to modify. + * @param {*} value The value to add. + * @returns {Object} Returns `set`. + */ + function addSetEntry(set, value) { + // Don't return `set.add` because it's not chainable in IE 11. + set.add(value); + return set; + } + + /** + * A faster alternative to `Function#apply`, this function invokes `func` + * with the `this` binding of `thisArg` and the arguments of `args`. + * + * @private + * @param {Function} func The function to invoke. + * @param {*} thisArg The `this` binding of `func`. + * @param {Array} args The arguments to invoke `func` with. + * @returns {*} Returns the result of `func`. + */ + function apply(func, thisArg, args) { + switch (args.length) { + case 0: return func.call(thisArg); + case 1: return func.call(thisArg, args[0]); + case 2: return func.call(thisArg, args[0], args[1]); + case 3: return func.call(thisArg, args[0], args[1], args[2]); + } + return func.apply(thisArg, args); + } + + /** + * A specialized version of `baseAggregator` for arrays. + * + * @private + * @param {Array} [array] The array to iterate over. + * @param {Function} setter The function to set `accumulator` values. + * @param {Function} iteratee The iteratee to transform keys. + * @param {Object} accumulator The initial aggregated object. + * @returns {Function} Returns `accumulator`. + */ + function arrayAggregator(array, setter, iteratee, accumulator) { + var index = -1, + length = array == null ? 0 : array.length; + + while (++index < length) { + var value = array[index]; + setter(accumulator, value, iteratee(value), array); + } + return accumulator; + } + + /** + * A specialized version of `_.forEach` for arrays without support for + * iteratee shorthands. + * + * @private + * @param {Array} [array] The array to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @returns {Array} Returns `array`. + */ + function arrayEach(array, iteratee) { + var index = -1, + length = array == null ? 0 : array.length; + + while (++index < length) { + if (iteratee(array[index], index, array) === false) { + break; + } + } + return array; + } + + /** + * A specialized version of `_.forEachRight` for arrays without support for + * iteratee shorthands. + * + * @private + * @param {Array} [array] The array to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @returns {Array} Returns `array`. + */ + function arrayEachRight(array, iteratee) { + var length = array == null ? 0 : array.length; + + while (length--) { + if (iteratee(array[length], length, array) === false) { + break; + } + } + return array; + } + + /** + * A specialized version of `_.every` for arrays without support for + * iteratee shorthands. + * + * @private + * @param {Array} [array] The array to iterate over. + * @param {Function} predicate The function invoked per iteration. + * @returns {boolean} Returns `true` if all elements pass the predicate check, + * else `false`. + */ + function arrayEvery(array, predicate) { + var index = -1, + length = array == null ? 0 : array.length; + + while (++index < length) { + if (!predicate(array[index], index, array)) { + return false; + } + } + return true; + } + + /** + * A specialized version of `_.filter` for arrays without support for + * iteratee shorthands. + * + * @private + * @param {Array} [array] The array to iterate over. + * @param {Function} predicate The function invoked per iteration. + * @returns {Array} Returns the new filtered array. + */ + function arrayFilter(array, predicate) { + var index = -1, + length = array == null ? 0 : array.length, + resIndex = 0, + result = []; + + while (++index < length) { + var value = array[index]; + if (predicate(value, index, array)) { + result[resIndex++] = value; + } + } + return result; + } + + /** + * A specialized version of `_.includes` for arrays without support for + * specifying an index to search from. + * + * @private + * @param {Array} [array] The array to inspect. + * @param {*} target The value to search for. + * @returns {boolean} Returns `true` if `target` is found, else `false`. + */ + function arrayIncludes(array, value) { + var length = array == null ? 0 : array.length; + return !!length && baseIndexOf(array, value, 0) > -1; + } + + /** + * This function is like `arrayIncludes` except that it accepts a comparator. + * + * @private + * @param {Array} [array] The array to inspect. + * @param {*} target The value to search for. + * @param {Function} comparator The comparator invoked per element. + * @returns {boolean} Returns `true` if `target` is found, else `false`. + */ + function arrayIncludesWith(array, value, comparator) { + var index = -1, + length = array == null ? 0 : array.length; + + while (++index < length) { + if (comparator(value, array[index])) { + return true; + } + } + return false; + } + + /** + * A specialized version of `_.map` for arrays without support for iteratee + * shorthands. + * + * @private + * @param {Array} [array] The array to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @returns {Array} Returns the new mapped array. + */ + function arrayMap(array, iteratee) { + var index = -1, + length = array == null ? 0 : array.length, + result = Array(length); + + while (++index < length) { + result[index] = iteratee(array[index], index, array); + } + return result; + } + + /** + * Appends the elements of `values` to `array`. + * + * @private + * @param {Array} array The array to modify. + * @param {Array} values The values to append. + * @returns {Array} Returns `array`. + */ + function arrayPush(array, values) { + var index = -1, + length = values.length, + offset = array.length; + + while (++index < length) { + array[offset + index] = values[index]; + } + return array; + } + + /** + * A specialized version of `_.reduce` for arrays without support for + * iteratee shorthands. + * + * @private + * @param {Array} [array] The array to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @param {*} [accumulator] The initial value. + * @param {boolean} [initAccum] Specify using the first element of `array` as + * the initial value. + * @returns {*} Returns the accumulated value. + */ + function arrayReduce(array, iteratee, accumulator, initAccum) { + var index = -1, + length = array == null ? 0 : array.length; + + if (initAccum && length) { + accumulator = array[++index]; + } + while (++index < length) { + accumulator = iteratee(accumulator, array[index], index, array); + } + return accumulator; + } + + /** + * A specialized version of `_.reduceRight` for arrays without support for + * iteratee shorthands. + * + * @private + * @param {Array} [array] The array to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @param {*} [accumulator] The initial value. + * @param {boolean} [initAccum] Specify using the last element of `array` as + * the initial value. + * @returns {*} Returns the accumulated value. + */ + function arrayReduceRight(array, iteratee, accumulator, initAccum) { + var length = array == null ? 0 : array.length; + if (initAccum && length) { + accumulator = array[--length]; + } + while (length--) { + accumulator = iteratee(accumulator, array[length], length, array); + } + return accumulator; + } + + /** + * A specialized version of `_.some` for arrays without support for iteratee + * shorthands. + * + * @private + * @param {Array} [array] The array to iterate over. + * @param {Function} predicate The function invoked per iteration. + * @returns {boolean} Returns `true` if any element passes the predicate check, + * else `false`. + */ + function arraySome(array, predicate) { + var index = -1, + length = array == null ? 0 : array.length; + + while (++index < length) { + if (predicate(array[index], index, array)) { + return true; + } + } + return false; + } + + /** + * Gets the size of an ASCII `string`. + * + * @private + * @param {string} string The string inspect. + * @returns {number} Returns the string size. + */ + var asciiSize = baseProperty('length'); + + /** + * Converts an ASCII `string` to an array. + * + * @private + * @param {string} string The string to convert. + * @returns {Array} Returns the converted array. + */ + function asciiToArray(string) { + return string.split(''); + } + + /** + * Splits an ASCII `string` into an array of its words. + * + * @private + * @param {string} The string to inspect. + * @returns {Array} Returns the words of `string`. + */ + function asciiWords(string) { + return string.match(reAsciiWord) || []; + } + + /** + * The base implementation of methods like `_.findKey` and `_.findLastKey`, + * without support for iteratee shorthands, which iterates over `collection` + * using `eachFunc`. + * + * @private + * @param {Array|Object} collection The collection to inspect. + * @param {Function} predicate The function invoked per iteration. + * @param {Function} eachFunc The function to iterate over `collection`. + * @returns {*} Returns the found element or its key, else `undefined`. + */ + function baseFindKey(collection, predicate, eachFunc) { + var result; + eachFunc(collection, function(value, key, collection) { + if (predicate(value, key, collection)) { + result = key; + return false; + } + }); + return result; + } + + /** + * The base implementation of `_.findIndex` and `_.findLastIndex` without + * support for iteratee shorthands. + * + * @private + * @param {Array} array The array to inspect. + * @param {Function} predicate The function invoked per iteration. + * @param {number} fromIndex The index to search from. + * @param {boolean} [fromRight] Specify iterating from right to left. + * @returns {number} Returns the index of the matched value, else `-1`. + */ + function baseFindIndex(array, predicate, fromIndex, fromRight) { + var length = array.length, + index = fromIndex + (fromRight ? 1 : -1); + + while ((fromRight ? index-- : ++index < length)) { + if (predicate(array[index], index, array)) { + return index; + } + } + return -1; + } + + /** + * The base implementation of `_.indexOf` without `fromIndex` bounds checks. + * + * @private + * @param {Array} array The array to inspect. + * @param {*} value The value to search for. + * @param {number} fromIndex The index to search from. + * @returns {number} Returns the index of the matched value, else `-1`. + */ + function baseIndexOf(array, value, fromIndex) { + return value === value + ? strictIndexOf(array, value, fromIndex) + : baseFindIndex(array, baseIsNaN, fromIndex); + } + + /** + * This function is like `baseIndexOf` except that it accepts a comparator. + * + * @private + * @param {Array} array The array to inspect. + * @param {*} value The value to search for. + * @param {number} fromIndex The index to search from. + * @param {Function} comparator The comparator invoked per element. + * @returns {number} Returns the index of the matched value, else `-1`. + */ + function baseIndexOfWith(array, value, fromIndex, comparator) { + var index = fromIndex - 1, + length = array.length; + + while (++index < length) { + if (comparator(array[index], value)) { + return index; + } + } + return -1; + } + + /** + * The base implementation of `_.isNaN` without support for number objects. + * + * @private + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is `NaN`, else `false`. + */ + function baseIsNaN(value) { + return value !== value; + } + + /** + * The base implementation of `_.mean` and `_.meanBy` without support for + * iteratee shorthands. + * + * @private + * @param {Array} array The array to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @returns {number} Returns the mean. + */ + function baseMean(array, iteratee) { + var length = array == null ? 0 : array.length; + return length ? (baseSum(array, iteratee) / length) : NAN; + } + + /** + * The base implementation of `_.property` without support for deep paths. + * + * @private + * @param {string} key The key of the property to get. + * @returns {Function} Returns the new accessor function. + */ + function baseProperty(key) { + return function(object) { + return object == null ? undefined : object[key]; + }; + } + + /** + * The base implementation of `_.propertyOf` without support for deep paths. + * + * @private + * @param {Object} object The object to query. + * @returns {Function} Returns the new accessor function. + */ + function basePropertyOf(object) { + return function(key) { + return object == null ? undefined : object[key]; + }; + } + + /** + * The base implementation of `_.reduce` and `_.reduceRight`, without support + * for iteratee shorthands, which iterates over `collection` using `eachFunc`. + * + * @private + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @param {*} accumulator The initial value. + * @param {boolean} initAccum Specify using the first or last element of + * `collection` as the initial value. + * @param {Function} eachFunc The function to iterate over `collection`. + * @returns {*} Returns the accumulated value. + */ + function baseReduce(collection, iteratee, accumulator, initAccum, eachFunc) { + eachFunc(collection, function(value, index, collection) { + accumulator = initAccum + ? (initAccum = false, value) + : iteratee(accumulator, value, index, collection); + }); + return accumulator; + } + + /** + * The base implementation of `_.sortBy` which uses `comparer` to define the + * sort order of `array` and replaces criteria objects with their corresponding + * values. + * + * @private + * @param {Array} array The array to sort. + * @param {Function} comparer The function to define sort order. + * @returns {Array} Returns `array`. + */ + function baseSortBy(array, comparer) { + var length = array.length; + + array.sort(comparer); + while (length--) { + array[length] = array[length].value; + } + return array; + } + + /** + * The base implementation of `_.sum` and `_.sumBy` without support for + * iteratee shorthands. + * + * @private + * @param {Array} array The array to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @returns {number} Returns the sum. + */ + function baseSum(array, iteratee) { + var result, + index = -1, + length = array.length; + + while (++index < length) { + var current = iteratee(array[index]); + if (current !== undefined) { + result = result === undefined ? current : (result + current); + } + } + return result; + } + + /** + * The base implementation of `_.times` without support for iteratee shorthands + * or max array length checks. + * + * @private + * @param {number} n The number of times to invoke `iteratee`. + * @param {Function} iteratee The function invoked per iteration. + * @returns {Array} Returns the array of results. + */ + function baseTimes(n, iteratee) { + var index = -1, + result = Array(n); + + while (++index < n) { + result[index] = iteratee(index); + } + return result; + } + + /** + * The base implementation of `_.toPairs` and `_.toPairsIn` which creates an array + * of key-value pairs for `object` corresponding to the property names of `props`. + * + * @private + * @param {Object} object The object to query. + * @param {Array} props The property names to get values for. + * @returns {Object} Returns the key-value pairs. + */ + function baseToPairs(object, props) { + return arrayMap(props, function(key) { + return [key, object[key]]; + }); + } + + /** + * The base implementation of `_.unary` without support for storing metadata. + * + * @private + * @param {Function} func The function to cap arguments for. + * @returns {Function} Returns the new capped function. + */ + function baseUnary(func) { + return function(value) { + return func(value); + }; + } + + /** + * The base implementation of `_.values` and `_.valuesIn` which creates an + * array of `object` property values corresponding to the property names + * of `props`. + * + * @private + * @param {Object} object The object to query. + * @param {Array} props The property names to get values for. + * @returns {Object} Returns the array of property values. + */ + function baseValues(object, props) { + return arrayMap(props, function(key) { + return object[key]; + }); + } + + /** + * Checks if a `cache` value for `key` exists. + * + * @private + * @param {Object} cache The cache to query. + * @param {string} key The key of the entry to check. + * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`. + */ + function cacheHas(cache, key) { + return cache.has(key); + } + + /** + * Used by `_.trim` and `_.trimStart` to get the index of the first string symbol + * that is not found in the character symbols. + * + * @private + * @param {Array} strSymbols The string symbols to inspect. + * @param {Array} chrSymbols The character symbols to find. + * @returns {number} Returns the index of the first unmatched string symbol. + */ + function charsStartIndex(strSymbols, chrSymbols) { + var index = -1, + length = strSymbols.length; + + while (++index < length && baseIndexOf(chrSymbols, strSymbols[index], 0) > -1) {} + return index; + } + + /** + * Used by `_.trim` and `_.trimEnd` to get the index of the last string symbol + * that is not found in the character symbols. + * + * @private + * @param {Array} strSymbols The string symbols to inspect. + * @param {Array} chrSymbols The character symbols to find. + * @returns {number} Returns the index of the last unmatched string symbol. + */ + function charsEndIndex(strSymbols, chrSymbols) { + var index = strSymbols.length; + + while (index-- && baseIndexOf(chrSymbols, strSymbols[index], 0) > -1) {} + return index; + } + + /** + * Gets the number of `placeholder` occurrences in `array`. + * + * @private + * @param {Array} array The array to inspect. + * @param {*} placeholder The placeholder to search for. + * @returns {number} Returns the placeholder count. + */ + function countHolders(array, placeholder) { + var length = array.length, + result = 0; + + while (length--) { + if (array[length] === placeholder) { + ++result; + } + } + return result; + } + + /** + * Used by `_.deburr` to convert Latin-1 Supplement and Latin Extended-A + * letters to basic Latin letters. + * + * @private + * @param {string} letter The matched letter to deburr. + * @returns {string} Returns the deburred letter. + */ + var deburrLetter = basePropertyOf(deburredLetters); + + /** + * Used by `_.escape` to convert characters to HTML entities. + * + * @private + * @param {string} chr The matched character to escape. + * @returns {string} Returns the escaped character. + */ + var escapeHtmlChar = basePropertyOf(htmlEscapes); + + /** + * Used by `_.template` to escape characters for inclusion in compiled string literals. + * + * @private + * @param {string} chr The matched character to escape. + * @returns {string} Returns the escaped character. + */ + function escapeStringChar(chr) { + return '\\' + stringEscapes[chr]; + } + + /** + * Gets the value at `key` of `object`. + * + * @private + * @param {Object} [object] The object to query. + * @param {string} key The key of the property to get. + * @returns {*} Returns the property value. + */ + function getValue(object, key) { + return object == null ? undefined : object[key]; + } + + /** + * Checks if `string` contains Unicode symbols. + * + * @private + * @param {string} string The string to inspect. + * @returns {boolean} Returns `true` if a symbol is found, else `false`. + */ + function hasUnicode(string) { + return reHasUnicode.test(string); + } + + /** + * Checks if `string` contains a word composed of Unicode symbols. + * + * @private + * @param {string} string The string to inspect. + * @returns {boolean} Returns `true` if a word is found, else `false`. + */ + function hasUnicodeWord(string) { + return reHasUnicodeWord.test(string); + } + + /** + * Converts `iterator` to an array. + * + * @private + * @param {Object} iterator The iterator to convert. + * @returns {Array} Returns the converted array. + */ + function iteratorToArray(iterator) { + var data, + result = []; + + while (!(data = iterator.next()).done) { + result.push(data.value); + } + return result; + } + + /** + * Converts `map` to its key-value pairs. + * + * @private + * @param {Object} map The map to convert. + * @returns {Array} Returns the key-value pairs. + */ + function mapToArray(map) { + var index = -1, + result = Array(map.size); + + map.forEach(function(value, key) { + result[++index] = [key, value]; + }); + return result; + } + + /** + * Creates a unary function that invokes `func` with its argument transformed. + * + * @private + * @param {Function} func The function to wrap. + * @param {Function} transform The argument transform. + * @returns {Function} Returns the new function. + */ + function overArg(func, transform) { + return function(arg) { + return func(transform(arg)); + }; + } + + /** + * Replaces all `placeholder` elements in `array` with an internal placeholder + * and returns an array of their indexes. + * + * @private + * @param {Array} array The array to modify. + * @param {*} placeholder The placeholder to replace. + * @returns {Array} Returns the new array of placeholder indexes. + */ + function replaceHolders(array, placeholder) { + var index = -1, + length = array.length, + resIndex = 0, + result = []; + + while (++index < length) { + var value = array[index]; + if (value === placeholder || value === PLACEHOLDER) { + array[index] = PLACEHOLDER; + result[resIndex++] = index; + } + } + return result; + } + + /** + * Converts `set` to an array of its values. + * + * @private + * @param {Object} set The set to convert. + * @returns {Array} Returns the values. + */ + function setToArray(set) { + var index = -1, + result = Array(set.size); + + set.forEach(function(value) { + result[++index] = value; + }); + return result; + } + + /** + * Converts `set` to its value-value pairs. + * + * @private + * @param {Object} set The set to convert. + * @returns {Array} Returns the value-value pairs. + */ + function setToPairs(set) { + var index = -1, + result = Array(set.size); + + set.forEach(function(value) { + result[++index] = [value, value]; + }); + return result; + } + + /** + * A specialized version of `_.indexOf` which performs strict equality + * comparisons of values, i.e. `===`. + * + * @private + * @param {Array} array The array to inspect. + * @param {*} value The value to search for. + * @param {number} fromIndex The index to search from. + * @returns {number} Returns the index of the matched value, else `-1`. + */ + function strictIndexOf(array, value, fromIndex) { + var index = fromIndex - 1, + length = array.length; + + while (++index < length) { + if (array[index] === value) { + return index; + } + } + return -1; + } + + /** + * A specialized version of `_.lastIndexOf` which performs strict equality + * comparisons of values, i.e. `===`. + * + * @private + * @param {Array} array The array to inspect. + * @param {*} value The value to search for. + * @param {number} fromIndex The index to search from. + * @returns {number} Returns the index of the matched value, else `-1`. + */ + function strictLastIndexOf(array, value, fromIndex) { + var index = fromIndex + 1; + while (index--) { + if (array[index] === value) { + return index; + } + } + return index; + } + + /** + * Gets the number of symbols in `string`. + * + * @private + * @param {string} string The string to inspect. + * @returns {number} Returns the string size. + */ + function stringSize(string) { + return hasUnicode(string) + ? unicodeSize(string) + : asciiSize(string); + } + + /** + * Converts `string` to an array. + * + * @private + * @param {string} string The string to convert. + * @returns {Array} Returns the converted array. + */ + function stringToArray(string) { + return hasUnicode(string) + ? unicodeToArray(string) + : asciiToArray(string); + } + + /** + * Used by `_.unescape` to convert HTML entities to characters. + * + * @private + * @param {string} chr The matched character to unescape. + * @returns {string} Returns the unescaped character. + */ + var unescapeHtmlChar = basePropertyOf(htmlUnescapes); + + /** + * Gets the size of a Unicode `string`. + * + * @private + * @param {string} string The string inspect. + * @returns {number} Returns the string size. + */ + function unicodeSize(string) { + var result = reUnicode.lastIndex = 0; + while (reUnicode.test(string)) { + ++result; + } + return result; + } + + /** + * Converts a Unicode `string` to an array. + * + * @private + * @param {string} string The string to convert. + * @returns {Array} Returns the converted array. + */ + function unicodeToArray(string) { + return string.match(reUnicode) || []; + } + + /** + * Splits a Unicode `string` into an array of its words. + * + * @private + * @param {string} The string to inspect. + * @returns {Array} Returns the words of `string`. + */ + function unicodeWords(string) { + return string.match(reUnicodeWord) || []; + } + + /*--------------------------------------------------------------------------*/ + + /** + * Create a new pristine `lodash` function using the `context` object. + * + * @static + * @memberOf _ + * @since 1.1.0 + * @category Util + * @param {Object} [context=root] The context object. + * @returns {Function} Returns a new `lodash` function. + * @example + * + * _.mixin({ 'foo': _.constant('foo') }); + * + * var lodash = _.runInContext(); + * lodash.mixin({ 'bar': lodash.constant('bar') }); + * + * _.isFunction(_.foo); + * // => true + * _.isFunction(_.bar); + * // => false + * + * lodash.isFunction(lodash.foo); + * // => false + * lodash.isFunction(lodash.bar); + * // => true + * + * // Create a suped-up `defer` in Node.js. + * var defer = _.runInContext({ 'setTimeout': setImmediate }).defer; + */ + var runInContext = (function runInContext(context) { + context = context == null ? root : _.defaults(root.Object(), context, _.pick(root, contextProps)); + + /** Built-in constructor references. */ + var Array = context.Array, + Date = context.Date, + Error = context.Error, + Function = context.Function, + Math = context.Math, + Object = context.Object, + RegExp = context.RegExp, + String = context.String, + TypeError = context.TypeError; + + /** Used for built-in method references. */ + var arrayProto = Array.prototype, + funcProto = Function.prototype, + objectProto = Object.prototype; + + /** Used to detect overreaching core-js shims. */ + var coreJsData = context['__core-js_shared__']; + + /** Used to resolve the decompiled source of functions. */ + var funcToString = funcProto.toString; + + /** Used to check objects for own properties. */ + var hasOwnProperty = objectProto.hasOwnProperty; + + /** Used to generate unique IDs. */ + var idCounter = 0; + + /** Used to detect methods masquerading as native. */ + var maskSrcKey = (function() { + var uid = /[^.]+$/.exec(coreJsData && coreJsData.keys && coreJsData.keys.IE_PROTO || ''); + return uid ? ('Symbol(src)_1.' + uid) : ''; + }()); + + /** + * Used to resolve the + * [`toStringTag`](http://ecma-international.org/ecma-262/7.0/#sec-object.prototype.tostring) + * of values. + */ + var nativeObjectToString = objectProto.toString; + + /** Used to infer the `Object` constructor. */ + var objectCtorString = funcToString.call(Object); + + /** Used to restore the original `_` reference in `_.noConflict`. */ + var oldDash = root._; + + /** Used to detect if a method is native. */ + var reIsNative = RegExp('^' + + funcToString.call(hasOwnProperty).replace(reRegExpChar, '\\$&') + .replace(/hasOwnProperty|(function).*?(?=\\\()| for .+?(?=\\\])/g, '$1.*?') + '$' + ); + + /** Built-in value references. */ + var Buffer = moduleExports ? context.Buffer : undefined, + Symbol = context.Symbol, + Uint8Array = context.Uint8Array, + allocUnsafe = Buffer ? Buffer.allocUnsafe : undefined, + getPrototype = overArg(Object.getPrototypeOf, Object), + objectCreate = Object.create, + propertyIsEnumerable = objectProto.propertyIsEnumerable, + splice = arrayProto.splice, + spreadableSymbol = Symbol ? Symbol.isConcatSpreadable : undefined, + symIterator = Symbol ? Symbol.iterator : undefined, + symToStringTag = Symbol ? Symbol.toStringTag : undefined; + + var defineProperty = (function() { + try { + var func = getNative(Object, 'defineProperty'); + func({}, '', {}); + return func; + } catch (e) {} + }()); + + /** Mocked built-ins. */ + var ctxClearTimeout = context.clearTimeout !== root.clearTimeout && context.clearTimeout, + ctxNow = Date && Date.now !== root.Date.now && Date.now, + ctxSetTimeout = context.setTimeout !== root.setTimeout && context.setTimeout; + + /* Built-in method references for those with the same name as other `lodash` methods. */ + var nativeCeil = Math.ceil, + nativeFloor = Math.floor, + nativeGetSymbols = Object.getOwnPropertySymbols, + nativeIsBuffer = Buffer ? Buffer.isBuffer : undefined, + nativeIsFinite = context.isFinite, + nativeJoin = arrayProto.join, + nativeKeys = overArg(Object.keys, Object), + nativeMax = Math.max, + nativeMin = Math.min, + nativeNow = Date.now, + nativeParseInt = context.parseInt, + nativeRandom = Math.random, + nativeReverse = arrayProto.reverse; + + /* Built-in method references that are verified to be native. */ + var DataView = getNative(context, 'DataView'), + Map = getNative(context, 'Map'), + Promise = getNative(context, 'Promise'), + Set = getNative(context, 'Set'), + WeakMap = getNative(context, 'WeakMap'), + nativeCreate = getNative(Object, 'create'); + + /** Used to store function metadata. */ + var metaMap = WeakMap && new WeakMap; + + /** Used to lookup unminified function names. */ + var realNames = {}; + + /** Used to detect maps, sets, and weakmaps. */ + var dataViewCtorString = toSource(DataView), + mapCtorString = toSource(Map), + promiseCtorString = toSource(Promise), + setCtorString = toSource(Set), + weakMapCtorString = toSource(WeakMap); + + /** Used to convert symbols to primitives and strings. */ + var symbolProto = Symbol ? Symbol.prototype : undefined, + symbolValueOf = symbolProto ? symbolProto.valueOf : undefined, + symbolToString = symbolProto ? symbolProto.toString : undefined; + + /*------------------------------------------------------------------------*/ + + /** + * Creates a `lodash` object which wraps `value` to enable implicit method + * chain sequences. Methods that operate on and return arrays, collections, + * and functions can be chained together. Methods that retrieve a single value + * or may return a primitive value will automatically end the chain sequence + * and return the unwrapped value. Otherwise, the value must be unwrapped + * with `_#value`. + * + * Explicit chain sequences, which must be unwrapped with `_#value`, may be + * enabled using `_.chain`. + * + * The execution of chained methods is lazy, that is, it's deferred until + * `_#value` is implicitly or explicitly called. + * + * Lazy evaluation allows several methods to support shortcut fusion. + * Shortcut fusion is an optimization to merge iteratee calls; this avoids + * the creation of intermediate arrays and can greatly reduce the number of + * iteratee executions. Sections of a chain sequence qualify for shortcut + * fusion if the section is applied to an array and iteratees accept only + * one argument. The heuristic for whether a section qualifies for shortcut + * fusion is subject to change. + * + * Chaining is supported in custom builds as long as the `_#value` method is + * directly or indirectly included in the build. + * + * In addition to lodash methods, wrappers have `Array` and `String` methods. + * + * The wrapper `Array` methods are: + * `concat`, `join`, `pop`, `push`, `shift`, `sort`, `splice`, and `unshift` + * + * The wrapper `String` methods are: + * `replace` and `split` + * + * The wrapper methods that support shortcut fusion are: + * `at`, `compact`, `drop`, `dropRight`, `dropWhile`, `filter`, `find`, + * `findLast`, `head`, `initial`, `last`, `map`, `reject`, `reverse`, `slice`, + * `tail`, `take`, `takeRight`, `takeRightWhile`, `takeWhile`, and `toArray` + * + * The chainable wrapper methods are: + * `after`, `ary`, `assign`, `assignIn`, `assignInWith`, `assignWith`, `at`, + * `before`, `bind`, `bindAll`, `bindKey`, `castArray`, `chain`, `chunk`, + * `commit`, `compact`, `concat`, `conforms`, `constant`, `countBy`, `create`, + * `curry`, `debounce`, `defaults`, `defaultsDeep`, `defer`, `delay`, + * `difference`, `differenceBy`, `differenceWith`, `drop`, `dropRight`, + * `dropRightWhile`, `dropWhile`, `extend`, `extendWith`, `fill`, `filter`, + * `flatMap`, `flatMapDeep`, `flatMapDepth`, `flatten`, `flattenDeep`, + * `flattenDepth`, `flip`, `flow`, `flowRight`, `fromPairs`, `functions`, + * `functionsIn`, `groupBy`, `initial`, `intersection`, `intersectionBy`, + * `intersectionWith`, `invert`, `invertBy`, `invokeMap`, `iteratee`, `keyBy`, + * `keys`, `keysIn`, `map`, `mapKeys`, `mapValues`, `matches`, `matchesProperty`, + * `memoize`, `merge`, `mergeWith`, `method`, `methodOf`, `mixin`, `negate`, + * `nthArg`, `omit`, `omitBy`, `once`, `orderBy`, `over`, `overArgs`, + * `overEvery`, `overSome`, `partial`, `partialRight`, `partition`, `pick`, + * `pickBy`, `plant`, `property`, `propertyOf`, `pull`, `pullAll`, `pullAllBy`, + * `pullAllWith`, `pullAt`, `push`, `range`, `rangeRight`, `rearg`, `reject`, + * `remove`, `rest`, `reverse`, `sampleSize`, `set`, `setWith`, `shuffle`, + * `slice`, `sort`, `sortBy`, `splice`, `spread`, `tail`, `take`, `takeRight`, + * `takeRightWhile`, `takeWhile`, `tap`, `throttle`, `thru`, `toArray`, + * `toPairs`, `toPairsIn`, `toPath`, `toPlainObject`, `transform`, `unary`, + * `union`, `unionBy`, `unionWith`, `uniq`, `uniqBy`, `uniqWith`, `unset`, + * `unshift`, `unzip`, `unzipWith`, `update`, `updateWith`, `values`, + * `valuesIn`, `without`, `wrap`, `xor`, `xorBy`, `xorWith`, `zip`, + * `zipObject`, `zipObjectDeep`, and `zipWith` + * + * The wrapper methods that are **not** chainable by default are: + * `add`, `attempt`, `camelCase`, `capitalize`, `ceil`, `clamp`, `clone`, + * `cloneDeep`, `cloneDeepWith`, `cloneWith`, `conformsTo`, `deburr`, + * `defaultTo`, `divide`, `each`, `eachRight`, `endsWith`, `eq`, `escape`, + * `escapeRegExp`, `every`, `find`, `findIndex`, `findKey`, `findLast`, + * `findLastIndex`, `findLastKey`, `first`, `floor`, `forEach`, `forEachRight`, + * `forIn`, `forInRight`, `forOwn`, `forOwnRight`, `get`, `gt`, `gte`, `has`, + * `hasIn`, `head`, `identity`, `includes`, `indexOf`, `inRange`, `invoke`, + * `isArguments`, `isArray`, `isArrayBuffer`, `isArrayLike`, `isArrayLikeObject`, + * `isBoolean`, `isBuffer`, `isDate`, `isElement`, `isEmpty`, `isEqual`, + * `isEqualWith`, `isError`, `isFinite`, `isFunction`, `isInteger`, `isLength`, + * `isMap`, `isMatch`, `isMatchWith`, `isNaN`, `isNative`, `isNil`, `isNull`, + * `isNumber`, `isObject`, `isObjectLike`, `isPlainObject`, `isRegExp`, + * `isSafeInteger`, `isSet`, `isString`, `isUndefined`, `isTypedArray`, + * `isWeakMap`, `isWeakSet`, `join`, `kebabCase`, `last`, `lastIndexOf`, + * `lowerCase`, `lowerFirst`, `lt`, `lte`, `max`, `maxBy`, `mean`, `meanBy`, + * `min`, `minBy`, `multiply`, `noConflict`, `noop`, `now`, `nth`, `pad`, + * `padEnd`, `padStart`, `parseInt`, `pop`, `random`, `reduce`, `reduceRight`, + * `repeat`, `result`, `round`, `runInContext`, `sample`, `shift`, `size`, + * `snakeCase`, `some`, `sortedIndex`, `sortedIndexBy`, `sortedLastIndex`, + * `sortedLastIndexBy`, `startCase`, `startsWith`, `stubArray`, `stubFalse`, + * `stubObject`, `stubString`, `stubTrue`, `subtract`, `sum`, `sumBy`, + * `template`, `times`, `toFinite`, `toInteger`, `toJSON`, `toLength`, + * `toLower`, `toNumber`, `toSafeInteger`, `toString`, `toUpper`, `trim`, + * `trimEnd`, `trimStart`, `truncate`, `unescape`, `uniqueId`, `upperCase`, + * `upperFirst`, `value`, and `words` + * + * @name _ + * @constructor + * @category Seq + * @param {*} value The value to wrap in a `lodash` instance. + * @returns {Object} Returns the new `lodash` wrapper instance. + * @example + * + * function square(n) { + * return n * n; + * } + * + * var wrapped = _([1, 2, 3]); + * + * // Returns an unwrapped value. + * wrapped.reduce(_.add); + * // => 6 + * + * // Returns a wrapped value. + * var squares = wrapped.map(square); + * + * _.isArray(squares); + * // => false + * + * _.isArray(squares.value()); + * // => true + */ + function lodash(value) { + if (isObjectLike(value) && !isArray(value) && !(value instanceof LazyWrapper)) { + if (value instanceof LodashWrapper) { + return value; + } + if (hasOwnProperty.call(value, '__wrapped__')) { + return wrapperClone(value); + } + } + return new LodashWrapper(value); + } + + /** + * The base implementation of `_.create` without support for assigning + * properties to the created object. + * + * @private + * @param {Object} proto The object to inherit from. + * @returns {Object} Returns the new object. + */ + var baseCreate = (function() { + function object() {} + return function(proto) { + if (!isObject(proto)) { + return {}; + } + if (objectCreate) { + return objectCreate(proto); + } + object.prototype = proto; + var result = new object; + object.prototype = undefined; + return result; + }; + }()); + + /** + * The function whose prototype chain sequence wrappers inherit from. + * + * @private + */ + function baseLodash() { + // No operation performed. + } + + /** + * The base constructor for creating `lodash` wrapper objects. + * + * @private + * @param {*} value The value to wrap. + * @param {boolean} [chainAll] Enable explicit method chain sequences. + */ + function LodashWrapper(value, chainAll) { + this.__wrapped__ = value; + this.__actions__ = []; + this.__chain__ = !!chainAll; + this.__index__ = 0; + this.__values__ = undefined; + } + + /** + * By default, the template delimiters used by lodash are like those in + * embedded Ruby (ERB) as well as ES2015 template strings. Change the + * following template settings to use alternative delimiters. + * + * @static + * @memberOf _ + * @type {Object} + */ + lodash.templateSettings = { + + /** + * Used to detect `data` property values to be HTML-escaped. + * + * @memberOf _.templateSettings + * @type {RegExp} + */ + 'escape': reEscape, + + /** + * Used to detect code to be evaluated. + * + * @memberOf _.templateSettings + * @type {RegExp} + */ + 'evaluate': reEvaluate, + + /** + * Used to detect `data` property values to inject. + * + * @memberOf _.templateSettings + * @type {RegExp} + */ + 'interpolate': reInterpolate, + + /** + * Used to reference the data object in the template text. + * + * @memberOf _.templateSettings + * @type {string} + */ + 'variable': '', + + /** + * Used to import variables into the compiled template. + * + * @memberOf _.templateSettings + * @type {Object} + */ + 'imports': { + + /** + * A reference to the `lodash` function. + * + * @memberOf _.templateSettings.imports + * @type {Function} + */ + '_': lodash + } + }; + + // Ensure wrappers are instances of `baseLodash`. + lodash.prototype = baseLodash.prototype; + lodash.prototype.constructor = lodash; + + LodashWrapper.prototype = baseCreate(baseLodash.prototype); + LodashWrapper.prototype.constructor = LodashWrapper; + + /*------------------------------------------------------------------------*/ + + /** + * Creates a lazy wrapper object which wraps `value` to enable lazy evaluation. + * + * @private + * @constructor + * @param {*} value The value to wrap. + */ + function LazyWrapper(value) { + this.__wrapped__ = value; + this.__actions__ = []; + this.__dir__ = 1; + this.__filtered__ = false; + this.__iteratees__ = []; + this.__takeCount__ = MAX_ARRAY_LENGTH; + this.__views__ = []; + } + + /** + * Creates a clone of the lazy wrapper object. + * + * @private + * @name clone + * @memberOf LazyWrapper + * @returns {Object} Returns the cloned `LazyWrapper` object. + */ + function lazyClone() { + var result = new LazyWrapper(this.__wrapped__); + result.__actions__ = copyArray(this.__actions__); + result.__dir__ = this.__dir__; + result.__filtered__ = this.__filtered__; + result.__iteratees__ = copyArray(this.__iteratees__); + result.__takeCount__ = this.__takeCount__; + result.__views__ = copyArray(this.__views__); + return result; + } + + /** + * Reverses the direction of lazy iteration. + * + * @private + * @name reverse + * @memberOf LazyWrapper + * @returns {Object} Returns the new reversed `LazyWrapper` object. + */ + function lazyReverse() { + if (this.__filtered__) { + var result = new LazyWrapper(this); + result.__dir__ = -1; + result.__filtered__ = true; + } else { + result = this.clone(); + result.__dir__ *= -1; + } + return result; + } + + /** + * Extracts the unwrapped value from its lazy wrapper. + * + * @private + * @name value + * @memberOf LazyWrapper + * @returns {*} Returns the unwrapped value. + */ + function lazyValue() { + var array = this.__wrapped__.value(), + dir = this.__dir__, + isArr = isArray(array), + isRight = dir < 0, + arrLength = isArr ? array.length : 0, + view = getView(0, arrLength, this.__views__), + start = view.start, + end = view.end, + length = end - start, + index = isRight ? end : (start - 1), + iteratees = this.__iteratees__, + iterLength = iteratees.length, + resIndex = 0, + takeCount = nativeMin(length, this.__takeCount__); + + if (!isArr || (!isRight && arrLength == length && takeCount == length)) { + return baseWrapperValue(array, this.__actions__); + } + var result = []; + + outer: + while (length-- && resIndex < takeCount) { + index += dir; + + var iterIndex = -1, + value = array[index]; + + while (++iterIndex < iterLength) { + var data = iteratees[iterIndex], + iteratee = data.iteratee, + type = data.type, + computed = iteratee(value); + + if (type == LAZY_MAP_FLAG) { + value = computed; + } else if (!computed) { + if (type == LAZY_FILTER_FLAG) { + continue outer; + } else { + break outer; + } + } + } + result[resIndex++] = value; + } + return result; + } + + // Ensure `LazyWrapper` is an instance of `baseLodash`. + LazyWrapper.prototype = baseCreate(baseLodash.prototype); + LazyWrapper.prototype.constructor = LazyWrapper; + + /*------------------------------------------------------------------------*/ + + /** + * Creates a hash object. + * + * @private + * @constructor + * @param {Array} [entries] The key-value pairs to cache. + */ + function Hash(entries) { + var index = -1, + length = entries == null ? 0 : entries.length; + + this.clear(); + while (++index < length) { + var entry = entries[index]; + this.set(entry[0], entry[1]); + } + } + + /** + * Removes all key-value entries from the hash. + * + * @private + * @name clear + * @memberOf Hash + */ + function hashClear() { + this.__data__ = nativeCreate ? nativeCreate(null) : {}; + this.size = 0; + } + + /** + * Removes `key` and its value from the hash. + * + * @private + * @name delete + * @memberOf Hash + * @param {Object} hash The hash to modify. + * @param {string} key The key of the value to remove. + * @returns {boolean} Returns `true` if the entry was removed, else `false`. + */ + function hashDelete(key) { + var result = this.has(key) && delete this.__data__[key]; + this.size -= result ? 1 : 0; + return result; + } + + /** + * Gets the hash value for `key`. + * + * @private + * @name get + * @memberOf Hash + * @param {string} key The key of the value to get. + * @returns {*} Returns the entry value. + */ + function hashGet(key) { + var data = this.__data__; + if (nativeCreate) { + var result = data[key]; + return result === HASH_UNDEFINED ? undefined : result; + } + return hasOwnProperty.call(data, key) ? data[key] : undefined; + } + + /** + * Checks if a hash value for `key` exists. + * + * @private + * @name has + * @memberOf Hash + * @param {string} key The key of the entry to check. + * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`. + */ + function hashHas(key) { + var data = this.__data__; + return nativeCreate ? (data[key] !== undefined) : hasOwnProperty.call(data, key); + } + + /** + * Sets the hash `key` to `value`. + * + * @private + * @name set + * @memberOf Hash + * @param {string} key The key of the value to set. + * @param {*} value The value to set. + * @returns {Object} Returns the hash instance. + */ + function hashSet(key, value) { + var data = this.__data__; + this.size += this.has(key) ? 0 : 1; + data[key] = (nativeCreate && value === undefined) ? HASH_UNDEFINED : value; + return this; + } + + // Add methods to `Hash`. + Hash.prototype.clear = hashClear; + Hash.prototype['delete'] = hashDelete; + Hash.prototype.get = hashGet; + Hash.prototype.has = hashHas; + Hash.prototype.set = hashSet; + + /*------------------------------------------------------------------------*/ + + /** + * Creates an list cache object. + * + * @private + * @constructor + * @param {Array} [entries] The key-value pairs to cache. + */ + function ListCache(entries) { + var index = -1, + length = entries == null ? 0 : entries.length; + + this.clear(); + while (++index < length) { + var entry = entries[index]; + this.set(entry[0], entry[1]); + } + } + + /** + * Removes all key-value entries from the list cache. + * + * @private + * @name clear + * @memberOf ListCache + */ + function listCacheClear() { + this.__data__ = []; + this.size = 0; + } + + /** + * Removes `key` and its value from the list cache. + * + * @private + * @name delete + * @memberOf ListCache + * @param {string} key The key of the value to remove. + * @returns {boolean} Returns `true` if the entry was removed, else `false`. + */ + function listCacheDelete(key) { + var data = this.__data__, + index = assocIndexOf(data, key); + + if (index < 0) { + return false; + } + var lastIndex = data.length - 1; + if (index == lastIndex) { + data.pop(); + } else { + splice.call(data, index, 1); + } + --this.size; + return true; + } + + /** + * Gets the list cache value for `key`. + * + * @private + * @name get + * @memberOf ListCache + * @param {string} key The key of the value to get. + * @returns {*} Returns the entry value. + */ + function listCacheGet(key) { + var data = this.__data__, + index = assocIndexOf(data, key); + + return index < 0 ? undefined : data[index][1]; + } + + /** + * Checks if a list cache value for `key` exists. + * + * @private + * @name has + * @memberOf ListCache + * @param {string} key The key of the entry to check. + * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`. + */ + function listCacheHas(key) { + return assocIndexOf(this.__data__, key) > -1; + } + + /** + * Sets the list cache `key` to `value`. + * + * @private + * @name set + * @memberOf ListCache + * @param {string} key The key of the value to set. + * @param {*} value The value to set. + * @returns {Object} Returns the list cache instance. + */ + function listCacheSet(key, value) { + var data = this.__data__, + index = assocIndexOf(data, key); + + if (index < 0) { + ++this.size; + data.push([key, value]); + } else { + data[index][1] = value; + } + return this; + } + + // Add methods to `ListCache`. + ListCache.prototype.clear = listCacheClear; + ListCache.prototype['delete'] = listCacheDelete; + ListCache.prototype.get = listCacheGet; + ListCache.prototype.has = listCacheHas; + ListCache.prototype.set = listCacheSet; + + /*------------------------------------------------------------------------*/ + + /** + * Creates a map cache object to store key-value pairs. + * + * @private + * @constructor + * @param {Array} [entries] The key-value pairs to cache. + */ + function MapCache(entries) { + var index = -1, + length = entries == null ? 0 : entries.length; + + this.clear(); + while (++index < length) { + var entry = entries[index]; + this.set(entry[0], entry[1]); + } + } + + /** + * Removes all key-value entries from the map. + * + * @private + * @name clear + * @memberOf MapCache + */ + function mapCacheClear() { + this.size = 0; + this.__data__ = { + 'hash': new Hash, + 'map': new (Map || ListCache), + 'string': new Hash + }; + } + + /** + * Removes `key` and its value from the map. + * + * @private + * @name delete + * @memberOf MapCache + * @param {string} key The key of the value to remove. + * @returns {boolean} Returns `true` if the entry was removed, else `false`. + */ + function mapCacheDelete(key) { + var result = getMapData(this, key)['delete'](key); + this.size -= result ? 1 : 0; + return result; + } + + /** + * Gets the map value for `key`. + * + * @private + * @name get + * @memberOf MapCache + * @param {string} key The key of the value to get. + * @returns {*} Returns the entry value. + */ + function mapCacheGet(key) { + return getMapData(this, key).get(key); + } + + /** + * Checks if a map value for `key` exists. + * + * @private + * @name has + * @memberOf MapCache + * @param {string} key The key of the entry to check. + * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`. + */ + function mapCacheHas(key) { + return getMapData(this, key).has(key); + } + + /** + * Sets the map `key` to `value`. + * + * @private + * @name set + * @memberOf MapCache + * @param {string} key The key of the value to set. + * @param {*} value The value to set. + * @returns {Object} Returns the map cache instance. + */ + function mapCacheSet(key, value) { + var data = getMapData(this, key), + size = data.size; + + data.set(key, value); + this.size += data.size == size ? 0 : 1; + return this; + } + + // Add methods to `MapCache`. + MapCache.prototype.clear = mapCacheClear; + MapCache.prototype['delete'] = mapCacheDelete; + MapCache.prototype.get = mapCacheGet; + MapCache.prototype.has = mapCacheHas; + MapCache.prototype.set = mapCacheSet; + + /*------------------------------------------------------------------------*/ + + /** + * + * Creates an array cache object to store unique values. + * + * @private + * @constructor + * @param {Array} [values] The values to cache. + */ + function SetCache(values) { + var index = -1, + length = values == null ? 0 : values.length; + + this.__data__ = new MapCache; + while (++index < length) { + this.add(values[index]); + } + } + + /** + * Adds `value` to the array cache. + * + * @private + * @name add + * @memberOf SetCache + * @alias push + * @param {*} value The value to cache. + * @returns {Object} Returns the cache instance. + */ + function setCacheAdd(value) { + this.__data__.set(value, HASH_UNDEFINED); + return this; + } + + /** + * Checks if `value` is in the array cache. + * + * @private + * @name has + * @memberOf SetCache + * @param {*} value The value to search for. + * @returns {number} Returns `true` if `value` is found, else `false`. + */ + function setCacheHas(value) { + return this.__data__.has(value); + } + + // Add methods to `SetCache`. + SetCache.prototype.add = SetCache.prototype.push = setCacheAdd; + SetCache.prototype.has = setCacheHas; + + /*------------------------------------------------------------------------*/ + + /** + * Creates a stack cache object to store key-value pairs. + * + * @private + * @constructor + * @param {Array} [entries] The key-value pairs to cache. + */ + function Stack(entries) { + var data = this.__data__ = new ListCache(entries); + this.size = data.size; + } + + /** + * Removes all key-value entries from the stack. + * + * @private + * @name clear + * @memberOf Stack + */ + function stackClear() { + this.__data__ = new ListCache; + this.size = 0; + } + + /** + * Removes `key` and its value from the stack. + * + * @private + * @name delete + * @memberOf Stack + * @param {string} key The key of the value to remove. + * @returns {boolean} Returns `true` if the entry was removed, else `false`. + */ + function stackDelete(key) { + var data = this.__data__, + result = data['delete'](key); + + this.size = data.size; + return result; + } + + /** + * Gets the stack value for `key`. + * + * @private + * @name get + * @memberOf Stack + * @param {string} key The key of the value to get. + * @returns {*} Returns the entry value. + */ + function stackGet(key) { + return this.__data__.get(key); + } + + /** + * Checks if a stack value for `key` exists. + * + * @private + * @name has + * @memberOf Stack + * @param {string} key The key of the entry to check. + * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`. + */ + function stackHas(key) { + return this.__data__.has(key); + } + + /** + * Sets the stack `key` to `value`. + * + * @private + * @name set + * @memberOf Stack + * @param {string} key The key of the value to set. + * @param {*} value The value to set. + * @returns {Object} Returns the stack cache instance. + */ + function stackSet(key, value) { + var data = this.__data__; + if (data instanceof ListCache) { + var pairs = data.__data__; + if (!Map || (pairs.length < LARGE_ARRAY_SIZE - 1)) { + pairs.push([key, value]); + this.size = ++data.size; + return this; + } + data = this.__data__ = new MapCache(pairs); + } + data.set(key, value); + this.size = data.size; + return this; + } + + // Add methods to `Stack`. + Stack.prototype.clear = stackClear; + Stack.prototype['delete'] = stackDelete; + Stack.prototype.get = stackGet; + Stack.prototype.has = stackHas; + Stack.prototype.set = stackSet; + + /*------------------------------------------------------------------------*/ + + /** + * Creates an array of the enumerable property names of the array-like `value`. + * + * @private + * @param {*} value The value to query. + * @param {boolean} inherited Specify returning inherited property names. + * @returns {Array} Returns the array of property names. + */ + function arrayLikeKeys(value, inherited) { + var isArr = isArray(value), + isArg = !isArr && isArguments(value), + isBuff = !isArr && !isArg && isBuffer(value), + isType = !isArr && !isArg && !isBuff && isTypedArray(value), + skipIndexes = isArr || isArg || isBuff || isType, + result = skipIndexes ? baseTimes(value.length, String) : [], + length = result.length; + + for (var key in value) { + if ((inherited || hasOwnProperty.call(value, key)) && + !(skipIndexes && ( + // Safari 9 has enumerable `arguments.length` in strict mode. + key == 'length' || + // Node.js 0.10 has enumerable non-index properties on buffers. + (isBuff && (key == 'offset' || key == 'parent')) || + // PhantomJS 2 has enumerable non-index properties on typed arrays. + (isType && (key == 'buffer' || key == 'byteLength' || key == 'byteOffset')) || + // Skip index properties. + isIndex(key, length) + ))) { + result.push(key); + } + } + return result; + } + + /** + * A specialized version of `_.sample` for arrays. + * + * @private + * @param {Array} array The array to sample. + * @returns {*} Returns the random element. + */ + function arraySample(array) { + var length = array.length; + return length ? array[baseRandom(0, length - 1)] : undefined; + } + + /** + * A specialized version of `_.sampleSize` for arrays. + * + * @private + * @param {Array} array The array to sample. + * @param {number} n The number of elements to sample. + * @returns {Array} Returns the random elements. + */ + function arraySampleSize(array, n) { + return shuffleSelf(copyArray(array), baseClamp(n, 0, array.length)); + } + + /** + * A specialized version of `_.shuffle` for arrays. + * + * @private + * @param {Array} array The array to shuffle. + * @returns {Array} Returns the new shuffled array. + */ + function arrayShuffle(array) { + return shuffleSelf(copyArray(array)); + } + + /** + * This function is like `assignValue` except that it doesn't assign + * `undefined` values. + * + * @private + * @param {Object} object The object to modify. + * @param {string} key The key of the property to assign. + * @param {*} value The value to assign. + */ + function assignMergeValue(object, key, value) { + if ((value !== undefined && !eq(object[key], value)) || + (value === undefined && !(key in object))) { + baseAssignValue(object, key, value); + } + } + + /** + * Assigns `value` to `key` of `object` if the existing value is not equivalent + * using [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero) + * for equality comparisons. + * + * @private + * @param {Object} object The object to modify. + * @param {string} key The key of the property to assign. + * @param {*} value The value to assign. + */ + function assignValue(object, key, value) { + var objValue = object[key]; + if (!(hasOwnProperty.call(object, key) && eq(objValue, value)) || + (value === undefined && !(key in object))) { + baseAssignValue(object, key, value); + } + } + + /** + * Gets the index at which the `key` is found in `array` of key-value pairs. + * + * @private + * @param {Array} array The array to inspect. + * @param {*} key The key to search for. + * @returns {number} Returns the index of the matched value, else `-1`. + */ + function assocIndexOf(array, key) { + var length = array.length; + while (length--) { + if (eq(array[length][0], key)) { + return length; + } + } + return -1; + } + + /** + * Aggregates elements of `collection` on `accumulator` with keys transformed + * by `iteratee` and values set by `setter`. + * + * @private + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} setter The function to set `accumulator` values. + * @param {Function} iteratee The iteratee to transform keys. + * @param {Object} accumulator The initial aggregated object. + * @returns {Function} Returns `accumulator`. + */ + function baseAggregator(collection, setter, iteratee, accumulator) { + baseEach(collection, function(value, key, collection) { + setter(accumulator, value, iteratee(value), collection); + }); + return accumulator; + } + + /** + * The base implementation of `_.assign` without support for multiple sources + * or `customizer` functions. + * + * @private + * @param {Object} object The destination object. + * @param {Object} source The source object. + * @returns {Object} Returns `object`. + */ + function baseAssign(object, source) { + return object && copyObject(source, keys(source), object); + } + + /** + * The base implementation of `_.assignIn` without support for multiple sources + * or `customizer` functions. + * + * @private + * @param {Object} object The destination object. + * @param {Object} source The source object. + * @returns {Object} Returns `object`. + */ + function baseAssignIn(object, source) { + return object && copyObject(source, keysIn(source), object); + } + + /** + * The base implementation of `assignValue` and `assignMergeValue` without + * value checks. + * + * @private + * @param {Object} object The object to modify. + * @param {string} key The key of the property to assign. + * @param {*} value The value to assign. + */ + function baseAssignValue(object, key, value) { + if (key == '__proto__' && defineProperty) { + defineProperty(object, key, { + 'configurable': true, + 'enumerable': true, + 'value': value, + 'writable': true + }); + } else { + object[key] = value; + } + } + + /** + * The base implementation of `_.at` without support for individual paths. + * + * @private + * @param {Object} object The object to iterate over. + * @param {string[]} paths The property paths to pick. + * @returns {Array} Returns the picked elements. + */ + function baseAt(object, paths) { + var index = -1, + length = paths.length, + result = Array(length), + skip = object == null; + + while (++index < length) { + result[index] = skip ? undefined : get(object, paths[index]); + } + return result; + } + + /** + * The base implementation of `_.clamp` which doesn't coerce arguments. + * + * @private + * @param {number} number The number to clamp. + * @param {number} [lower] The lower bound. + * @param {number} upper The upper bound. + * @returns {number} Returns the clamped number. + */ + function baseClamp(number, lower, upper) { + if (number === number) { + if (upper !== undefined) { + number = number <= upper ? number : upper; + } + if (lower !== undefined) { + number = number >= lower ? number : lower; + } + } + return number; + } + + /** + * The base implementation of `_.clone` and `_.cloneDeep` which tracks + * traversed objects. + * + * @private + * @param {*} value The value to clone. + * @param {boolean} bitmask The bitmask flags. + * 1 - Deep clone + * 2 - Flatten inherited properties + * 4 - Clone symbols + * @param {Function} [customizer] The function to customize cloning. + * @param {string} [key] The key of `value`. + * @param {Object} [object] The parent object of `value`. + * @param {Object} [stack] Tracks traversed objects and their clone counterparts. + * @returns {*} Returns the cloned value. + */ + function baseClone(value, bitmask, customizer, key, object, stack) { + var result, + isDeep = bitmask & CLONE_DEEP_FLAG, + isFlat = bitmask & CLONE_FLAT_FLAG, + isFull = bitmask & CLONE_SYMBOLS_FLAG; + + if (customizer) { + result = object ? customizer(value, key, object, stack) : customizer(value); + } + if (result !== undefined) { + return result; + } + if (!isObject(value)) { + return value; + } + var isArr = isArray(value); + if (isArr) { + result = initCloneArray(value); + if (!isDeep) { + return copyArray(value, result); + } + } else { + var tag = getTag(value), + isFunc = tag == funcTag || tag == genTag; + + if (isBuffer(value)) { + return cloneBuffer(value, isDeep); + } + if (tag == objectTag || tag == argsTag || (isFunc && !object)) { + result = (isFlat || isFunc) ? {} : initCloneObject(value); + if (!isDeep) { + return isFlat + ? copySymbolsIn(value, baseAssignIn(result, value)) + : copySymbols(value, baseAssign(result, value)); + } + } else { + if (!cloneableTags[tag]) { + return object ? value : {}; + } + result = initCloneByTag(value, tag, baseClone, isDeep); + } + } + // Check for circular references and return its corresponding clone. + stack || (stack = new Stack); + var stacked = stack.get(value); + if (stacked) { + return stacked; + } + stack.set(value, result); + + var keysFunc = isFull + ? (isFlat ? getAllKeysIn : getAllKeys) + : (isFlat ? keysIn : keys); + + var props = isArr ? undefined : keysFunc(value); + arrayEach(props || value, function(subValue, key) { + if (props) { + key = subValue; + subValue = value[key]; + } + // Recursively populate clone (susceptible to call stack limits). + assignValue(result, key, baseClone(subValue, bitmask, customizer, key, value, stack)); + }); + return result; + } + + /** + * The base implementation of `_.conforms` which doesn't clone `source`. + * + * @private + * @param {Object} source The object of property predicates to conform to. + * @returns {Function} Returns the new spec function. + */ + function baseConforms(source) { + var props = keys(source); + return function(object) { + return baseConformsTo(object, source, props); + }; + } + + /** + * The base implementation of `_.conformsTo` which accepts `props` to check. + * + * @private + * @param {Object} object The object to inspect. + * @param {Object} source The object of property predicates to conform to. + * @returns {boolean} Returns `true` if `object` conforms, else `false`. + */ + function baseConformsTo(object, source, props) { + var length = props.length; + if (object == null) { + return !length; + } + object = Object(object); + while (length--) { + var key = props[length], + predicate = source[key], + value = object[key]; + + if ((value === undefined && !(key in object)) || !predicate(value)) { + return false; + } + } + return true; + } + + /** + * The base implementation of `_.delay` and `_.defer` which accepts `args` + * to provide to `func`. + * + * @private + * @param {Function} func The function to delay. + * @param {number} wait The number of milliseconds to delay invocation. + * @param {Array} args The arguments to provide to `func`. + * @returns {number|Object} Returns the timer id or timeout object. + */ + function baseDelay(func, wait, args) { + if (typeof func != 'function') { + throw new TypeError(FUNC_ERROR_TEXT); + } + return setTimeout(function() { func.apply(undefined, args); }, wait); + } + + /** + * The base implementation of methods like `_.difference` without support + * for excluding multiple arrays or iteratee shorthands. + * + * @private + * @param {Array} array The array to inspect. + * @param {Array} values The values to exclude. + * @param {Function} [iteratee] The iteratee invoked per element. + * @param {Function} [comparator] The comparator invoked per element. + * @returns {Array} Returns the new array of filtered values. + */ + function baseDifference(array, values, iteratee, comparator) { + var index = -1, + includes = arrayIncludes, + isCommon = true, + length = array.length, + result = [], + valuesLength = values.length; + + if (!length) { + return result; + } + if (iteratee) { + values = arrayMap(values, baseUnary(iteratee)); + } + if (comparator) { + includes = arrayIncludesWith; + isCommon = false; + } + else if (values.length >= LARGE_ARRAY_SIZE) { + includes = cacheHas; + isCommon = false; + values = new SetCache(values); + } + outer: + while (++index < length) { + var value = array[index], + computed = iteratee == null ? value : iteratee(value); + + value = (comparator || value !== 0) ? value : 0; + if (isCommon && computed === computed) { + var valuesIndex = valuesLength; + while (valuesIndex--) { + if (values[valuesIndex] === computed) { + continue outer; + } + } + result.push(value); + } + else if (!includes(values, computed, comparator)) { + result.push(value); + } + } + return result; + } + + /** + * The base implementation of `_.forEach` without support for iteratee shorthands. + * + * @private + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @returns {Array|Object} Returns `collection`. + */ + var baseEach = createBaseEach(baseForOwn); + + /** + * The base implementation of `_.forEachRight` without support for iteratee shorthands. + * + * @private + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @returns {Array|Object} Returns `collection`. + */ + var baseEachRight = createBaseEach(baseForOwnRight, true); + + /** + * The base implementation of `_.every` without support for iteratee shorthands. + * + * @private + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} predicate The function invoked per iteration. + * @returns {boolean} Returns `true` if all elements pass the predicate check, + * else `false` + */ + function baseEvery(collection, predicate) { + var result = true; + baseEach(collection, function(value, index, collection) { + result = !!predicate(value, index, collection); + return result; + }); + return result; + } + + /** + * The base implementation of methods like `_.max` and `_.min` which accepts a + * `comparator` to determine the extremum value. + * + * @private + * @param {Array} array The array to iterate over. + * @param {Function} iteratee The iteratee invoked per iteration. + * @param {Function} comparator The comparator used to compare values. + * @returns {*} Returns the extremum value. + */ + function baseExtremum(array, iteratee, comparator) { + var index = -1, + length = array.length; + + while (++index < length) { + var value = array[index], + current = iteratee(value); + + if (current != null && (computed === undefined + ? (current === current && !isSymbol(current)) + : comparator(current, computed) + )) { + var computed = current, + result = value; + } + } + return result; + } + + /** + * The base implementation of `_.fill` without an iteratee call guard. + * + * @private + * @param {Array} array The array to fill. + * @param {*} value The value to fill `array` with. + * @param {number} [start=0] The start position. + * @param {number} [end=array.length] The end position. + * @returns {Array} Returns `array`. + */ + function baseFill(array, value, start, end) { + var length = array.length; + + start = toInteger(start); + if (start < 0) { + start = -start > length ? 0 : (length + start); + } + end = (end === undefined || end > length) ? length : toInteger(end); + if (end < 0) { + end += length; + } + end = start > end ? 0 : toLength(end); + while (start < end) { + array[start++] = value; + } + return array; + } + + /** + * The base implementation of `_.filter` without support for iteratee shorthands. + * + * @private + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} predicate The function invoked per iteration. + * @returns {Array} Returns the new filtered array. + */ + function baseFilter(collection, predicate) { + var result = []; + baseEach(collection, function(value, index, collection) { + if (predicate(value, index, collection)) { + result.push(value); + } + }); + return result; + } + + /** + * The base implementation of `_.flatten` with support for restricting flattening. + * + * @private + * @param {Array} array The array to flatten. + * @param {number} depth The maximum recursion depth. + * @param {boolean} [predicate=isFlattenable] The function invoked per iteration. + * @param {boolean} [isStrict] Restrict to values that pass `predicate` checks. + * @param {Array} [result=[]] The initial result value. + * @returns {Array} Returns the new flattened array. + */ + function baseFlatten(array, depth, predicate, isStrict, result) { + var index = -1, + length = array.length; + + predicate || (predicate = isFlattenable); + result || (result = []); + + while (++index < length) { + var value = array[index]; + if (depth > 0 && predicate(value)) { + if (depth > 1) { + // Recursively flatten arrays (susceptible to call stack limits). + baseFlatten(value, depth - 1, predicate, isStrict, result); + } else { + arrayPush(result, value); + } + } else if (!isStrict) { + result[result.length] = value; + } + } + return result; + } + + /** + * The base implementation of `baseForOwn` which iterates over `object` + * properties returned by `keysFunc` and invokes `iteratee` for each property. + * Iteratee functions may exit iteration early by explicitly returning `false`. + * + * @private + * @param {Object} object The object to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @param {Function} keysFunc The function to get the keys of `object`. + * @returns {Object} Returns `object`. + */ + var baseFor = createBaseFor(); + + /** + * This function is like `baseFor` except that it iterates over properties + * in the opposite order. + * + * @private + * @param {Object} object The object to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @param {Function} keysFunc The function to get the keys of `object`. + * @returns {Object} Returns `object`. + */ + var baseForRight = createBaseFor(true); + + /** + * The base implementation of `_.forOwn` without support for iteratee shorthands. + * + * @private + * @param {Object} object The object to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @returns {Object} Returns `object`. + */ + function baseForOwn(object, iteratee) { + return object && baseFor(object, iteratee, keys); + } + + /** + * The base implementation of `_.forOwnRight` without support for iteratee shorthands. + * + * @private + * @param {Object} object The object to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @returns {Object} Returns `object`. + */ + function baseForOwnRight(object, iteratee) { + return object && baseForRight(object, iteratee, keys); + } + + /** + * The base implementation of `_.functions` which creates an array of + * `object` function property names filtered from `props`. + * + * @private + * @param {Object} object The object to inspect. + * @param {Array} props The property names to filter. + * @returns {Array} Returns the function names. + */ + function baseFunctions(object, props) { + return arrayFilter(props, function(key) { + return isFunction(object[key]); + }); + } + + /** + * The base implementation of `_.get` without support for default values. + * + * @private + * @param {Object} object The object to query. + * @param {Array|string} path The path of the property to get. + * @returns {*} Returns the resolved value. + */ + function baseGet(object, path) { + path = castPath(path, object); + + var index = 0, + length = path.length; + + while (object != null && index < length) { + object = object[toKey(path[index++])]; + } + return (index && index == length) ? object : undefined; + } + + /** + * The base implementation of `getAllKeys` and `getAllKeysIn` which uses + * `keysFunc` and `symbolsFunc` to get the enumerable property names and + * symbols of `object`. + * + * @private + * @param {Object} object The object to query. + * @param {Function} keysFunc The function to get the keys of `object`. + * @param {Function} symbolsFunc The function to get the symbols of `object`. + * @returns {Array} Returns the array of property names and symbols. + */ + function baseGetAllKeys(object, keysFunc, symbolsFunc) { + var result = keysFunc(object); + return isArray(object) ? result : arrayPush(result, symbolsFunc(object)); + } + + /** + * The base implementation of `getTag` without fallbacks for buggy environments. + * + * @private + * @param {*} value The value to query. + * @returns {string} Returns the `toStringTag`. + */ + function baseGetTag(value) { + if (value == null) { + return value === undefined ? undefinedTag : nullTag; + } + return (symToStringTag && symToStringTag in Object(value)) + ? getRawTag(value) + : objectToString(value); + } + + /** + * The base implementation of `_.gt` which doesn't coerce arguments. + * + * @private + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @returns {boolean} Returns `true` if `value` is greater than `other`, + * else `false`. + */ + function baseGt(value, other) { + return value > other; + } + + /** + * The base implementation of `_.has` without support for deep paths. + * + * @private + * @param {Object} [object] The object to query. + * @param {Array|string} key The key to check. + * @returns {boolean} Returns `true` if `key` exists, else `false`. + */ + function baseHas(object, key) { + return object != null && hasOwnProperty.call(object, key); + } + + /** + * The base implementation of `_.hasIn` without support for deep paths. + * + * @private + * @param {Object} [object] The object to query. + * @param {Array|string} key The key to check. + * @returns {boolean} Returns `true` if `key` exists, else `false`. + */ + function baseHasIn(object, key) { + return object != null && key in Object(object); + } + + /** + * The base implementation of `_.inRange` which doesn't coerce arguments. + * + * @private + * @param {number} number The number to check. + * @param {number} start The start of the range. + * @param {number} end The end of the range. + * @returns {boolean} Returns `true` if `number` is in the range, else `false`. + */ + function baseInRange(number, start, end) { + return number >= nativeMin(start, end) && number < nativeMax(start, end); + } + + /** + * The base implementation of methods like `_.intersection`, without support + * for iteratee shorthands, that accepts an array of arrays to inspect. + * + * @private + * @param {Array} arrays The arrays to inspect. + * @param {Function} [iteratee] The iteratee invoked per element. + * @param {Function} [comparator] The comparator invoked per element. + * @returns {Array} Returns the new array of shared values. + */ + function baseIntersection(arrays, iteratee, comparator) { + var includes = comparator ? arrayIncludesWith : arrayIncludes, + length = arrays[0].length, + othLength = arrays.length, + othIndex = othLength, + caches = Array(othLength), + maxLength = Infinity, + result = []; + + while (othIndex--) { + var array = arrays[othIndex]; + if (othIndex && iteratee) { + array = arrayMap(array, baseUnary(iteratee)); + } + maxLength = nativeMin(array.length, maxLength); + caches[othIndex] = !comparator && (iteratee || (length >= 120 && array.length >= 120)) + ? new SetCache(othIndex && array) + : undefined; + } + array = arrays[0]; + + var index = -1, + seen = caches[0]; + + outer: + while (++index < length && result.length < maxLength) { + var value = array[index], + computed = iteratee ? iteratee(value) : value; + + value = (comparator || value !== 0) ? value : 0; + if (!(seen + ? cacheHas(seen, computed) + : includes(result, computed, comparator) + )) { + othIndex = othLength; + while (--othIndex) { + var cache = caches[othIndex]; + if (!(cache + ? cacheHas(cache, computed) + : includes(arrays[othIndex], computed, comparator)) + ) { + continue outer; + } + } + if (seen) { + seen.push(computed); + } + result.push(value); + } + } + return result; + } + + /** + * The base implementation of `_.invert` and `_.invertBy` which inverts + * `object` with values transformed by `iteratee` and set by `setter`. + * + * @private + * @param {Object} object The object to iterate over. + * @param {Function} setter The function to set `accumulator` values. + * @param {Function} iteratee The iteratee to transform values. + * @param {Object} accumulator The initial inverted object. + * @returns {Function} Returns `accumulator`. + */ + function baseInverter(object, setter, iteratee, accumulator) { + baseForOwn(object, function(value, key, object) { + setter(accumulator, iteratee(value), key, object); + }); + return accumulator; + } + + /** + * The base implementation of `_.invoke` without support for individual + * method arguments. + * + * @private + * @param {Object} object The object to query. + * @param {Array|string} path The path of the method to invoke. + * @param {Array} args The arguments to invoke the method with. + * @returns {*} Returns the result of the invoked method. + */ + function baseInvoke(object, path, args) { + path = castPath(path, object); + object = parent(object, path); + var func = object == null ? object : object[toKey(last(path))]; + return func == null ? undefined : apply(func, object, args); + } + + /** + * The base implementation of `_.isArguments`. + * + * @private + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is an `arguments` object, + */ + function baseIsArguments(value) { + return isObjectLike(value) && baseGetTag(value) == argsTag; + } + + /** + * The base implementation of `_.isArrayBuffer` without Node.js optimizations. + * + * @private + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is an array buffer, else `false`. + */ + function baseIsArrayBuffer(value) { + return isObjectLike(value) && baseGetTag(value) == arrayBufferTag; + } + + /** + * The base implementation of `_.isDate` without Node.js optimizations. + * + * @private + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a date object, else `false`. + */ + function baseIsDate(value) { + return isObjectLike(value) && baseGetTag(value) == dateTag; + } + + /** + * The base implementation of `_.isEqual` which supports partial comparisons + * and tracks traversed objects. + * + * @private + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @param {boolean} bitmask The bitmask flags. + * 1 - Unordered comparison + * 2 - Partial comparison + * @param {Function} [customizer] The function to customize comparisons. + * @param {Object} [stack] Tracks traversed `value` and `other` objects. + * @returns {boolean} Returns `true` if the values are equivalent, else `false`. + */ + function baseIsEqual(value, other, bitmask, customizer, stack) { + if (value === other) { + return true; + } + if (value == null || other == null || (!isObjectLike(value) && !isObjectLike(other))) { + return value !== value && other !== other; + } + return baseIsEqualDeep(value, other, bitmask, customizer, baseIsEqual, stack); + } + + /** + * A specialized version of `baseIsEqual` for arrays and objects which performs + * deep comparisons and tracks traversed objects enabling objects with circular + * references to be compared. + * + * @private + * @param {Object} object The object to compare. + * @param {Object} other The other object to compare. + * @param {number} bitmask The bitmask flags. See `baseIsEqual` for more details. + * @param {Function} customizer The function to customize comparisons. + * @param {Function} equalFunc The function to determine equivalents of values. + * @param {Object} [stack] Tracks traversed `object` and `other` objects. + * @returns {boolean} Returns `true` if the objects are equivalent, else `false`. + */ + function baseIsEqualDeep(object, other, bitmask, customizer, equalFunc, stack) { + var objIsArr = isArray(object), + othIsArr = isArray(other), + objTag = objIsArr ? arrayTag : getTag(object), + othTag = othIsArr ? arrayTag : getTag(other); + + objTag = objTag == argsTag ? objectTag : objTag; + othTag = othTag == argsTag ? objectTag : othTag; + + var objIsObj = objTag == objectTag, + othIsObj = othTag == objectTag, + isSameTag = objTag == othTag; + + if (isSameTag && isBuffer(object)) { + if (!isBuffer(other)) { + return false; + } + objIsArr = true; + objIsObj = false; + } + if (isSameTag && !objIsObj) { + stack || (stack = new Stack); + return (objIsArr || isTypedArray(object)) + ? equalArrays(object, other, bitmask, customizer, equalFunc, stack) + : equalByTag(object, other, objTag, bitmask, customizer, equalFunc, stack); + } + if (!(bitmask & COMPARE_PARTIAL_FLAG)) { + var objIsWrapped = objIsObj && hasOwnProperty.call(object, '__wrapped__'), + othIsWrapped = othIsObj && hasOwnProperty.call(other, '__wrapped__'); + + if (objIsWrapped || othIsWrapped) { + var objUnwrapped = objIsWrapped ? object.value() : object, + othUnwrapped = othIsWrapped ? other.value() : other; + + stack || (stack = new Stack); + return equalFunc(objUnwrapped, othUnwrapped, bitmask, customizer, stack); + } + } + if (!isSameTag) { + return false; + } + stack || (stack = new Stack); + return equalObjects(object, other, bitmask, customizer, equalFunc, stack); + } + + /** + * The base implementation of `_.isMap` without Node.js optimizations. + * + * @private + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a map, else `false`. + */ + function baseIsMap(value) { + return isObjectLike(value) && getTag(value) == mapTag; + } + + /** + * The base implementation of `_.isMatch` without support for iteratee shorthands. + * + * @private + * @param {Object} object The object to inspect. + * @param {Object} source The object of property values to match. + * @param {Array} matchData The property names, values, and compare flags to match. + * @param {Function} [customizer] The function to customize comparisons. + * @returns {boolean} Returns `true` if `object` is a match, else `false`. + */ + function baseIsMatch(object, source, matchData, customizer) { + var index = matchData.length, + length = index, + noCustomizer = !customizer; + + if (object == null) { + return !length; + } + object = Object(object); + while (index--) { + var data = matchData[index]; + if ((noCustomizer && data[2]) + ? data[1] !== object[data[0]] + : !(data[0] in object) + ) { + return false; + } + } + while (++index < length) { + data = matchData[index]; + var key = data[0], + objValue = object[key], + srcValue = data[1]; + + if (noCustomizer && data[2]) { + if (objValue === undefined && !(key in object)) { + return false; + } + } else { + var stack = new Stack; + if (customizer) { + var result = customizer(objValue, srcValue, key, object, source, stack); + } + if (!(result === undefined + ? baseIsEqual(srcValue, objValue, COMPARE_PARTIAL_FLAG | COMPARE_UNORDERED_FLAG, customizer, stack) + : result + )) { + return false; + } + } + } + return true; + } + + /** + * The base implementation of `_.isNative` without bad shim checks. + * + * @private + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a native function, + * else `false`. + */ + function baseIsNative(value) { + if (!isObject(value) || isMasked(value)) { + return false; + } + var pattern = isFunction(value) ? reIsNative : reIsHostCtor; + return pattern.test(toSource(value)); + } + + /** + * The base implementation of `_.isRegExp` without Node.js optimizations. + * + * @private + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a regexp, else `false`. + */ + function baseIsRegExp(value) { + return isObjectLike(value) && baseGetTag(value) == regexpTag; + } + + /** + * The base implementation of `_.isSet` without Node.js optimizations. + * + * @private + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a set, else `false`. + */ + function baseIsSet(value) { + return isObjectLike(value) && getTag(value) == setTag; + } + + /** + * The base implementation of `_.isTypedArray` without Node.js optimizations. + * + * @private + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a typed array, else `false`. + */ + function baseIsTypedArray(value) { + return isObjectLike(value) && + isLength(value.length) && !!typedArrayTags[baseGetTag(value)]; + } + + /** + * The base implementation of `_.iteratee`. + * + * @private + * @param {*} [value=_.identity] The value to convert to an iteratee. + * @returns {Function} Returns the iteratee. + */ + function baseIteratee(value) { + // Don't store the `typeof` result in a variable to avoid a JIT bug in Safari 9. + // See https://bugs.webkit.org/show_bug.cgi?id=156034 for more details. + if (typeof value == 'function') { + return value; + } + if (value == null) { + return identity; + } + if (typeof value == 'object') { + return isArray(value) + ? baseMatchesProperty(value[0], value[1]) + : baseMatches(value); + } + return property(value); + } + + /** + * The base implementation of `_.keys` which doesn't treat sparse arrays as dense. + * + * @private + * @param {Object} object The object to query. + * @returns {Array} Returns the array of property names. + */ + function baseKeys(object) { + if (!isPrototype(object)) { + return nativeKeys(object); + } + var result = []; + for (var key in Object(object)) { + if (hasOwnProperty.call(object, key) && key != 'constructor') { + result.push(key); + } + } + return result; + } + + /** + * The base implementation of `_.keysIn` which doesn't treat sparse arrays as dense. + * + * @private + * @param {Object} object The object to query. + * @returns {Array} Returns the array of property names. + */ + function baseKeysIn(object) { + if (!isObject(object)) { + return nativeKeysIn(object); + } + var isProto = isPrototype(object), + result = []; + + for (var key in object) { + if (!(key == 'constructor' && (isProto || !hasOwnProperty.call(object, key)))) { + result.push(key); + } + } + return result; + } + + /** + * The base implementation of `_.lt` which doesn't coerce arguments. + * + * @private + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @returns {boolean} Returns `true` if `value` is less than `other`, + * else `false`. + */ + function baseLt(value, other) { + return value < other; + } + + /** + * The base implementation of `_.map` without support for iteratee shorthands. + * + * @private + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @returns {Array} Returns the new mapped array. + */ + function baseMap(collection, iteratee) { + var index = -1, + result = isArrayLike(collection) ? Array(collection.length) : []; + + baseEach(collection, function(value, key, collection) { + result[++index] = iteratee(value, key, collection); + }); + return result; + } + + /** + * The base implementation of `_.matches` which doesn't clone `source`. + * + * @private + * @param {Object} source The object of property values to match. + * @returns {Function} Returns the new spec function. + */ + function baseMatches(source) { + var matchData = getMatchData(source); + if (matchData.length == 1 && matchData[0][2]) { + return matchesStrictComparable(matchData[0][0], matchData[0][1]); + } + return function(object) { + return object === source || baseIsMatch(object, source, matchData); + }; + } + + /** + * The base implementation of `_.matchesProperty` which doesn't clone `srcValue`. + * + * @private + * @param {string} path The path of the property to get. + * @param {*} srcValue The value to match. + * @returns {Function} Returns the new spec function. + */ + function baseMatchesProperty(path, srcValue) { + if (isKey(path) && isStrictComparable(srcValue)) { + return matchesStrictComparable(toKey(path), srcValue); + } + return function(object) { + var objValue = get(object, path); + return (objValue === undefined && objValue === srcValue) + ? hasIn(object, path) + : baseIsEqual(srcValue, objValue, COMPARE_PARTIAL_FLAG | COMPARE_UNORDERED_FLAG); + }; + } + + /** + * The base implementation of `_.merge` without support for multiple sources. + * + * @private + * @param {Object} object The destination object. + * @param {Object} source The source object. + * @param {number} srcIndex The index of `source`. + * @param {Function} [customizer] The function to customize merged values. + * @param {Object} [stack] Tracks traversed source values and their merged + * counterparts. + */ + function baseMerge(object, source, srcIndex, customizer, stack) { + if (object === source) { + return; + } + baseFor(source, function(srcValue, key) { + if (isObject(srcValue)) { + stack || (stack = new Stack); + baseMergeDeep(object, source, key, srcIndex, baseMerge, customizer, stack); + } + else { + var newValue = customizer + ? customizer(object[key], srcValue, (key + ''), object, source, stack) + : undefined; + + if (newValue === undefined) { + newValue = srcValue; + } + assignMergeValue(object, key, newValue); + } + }, keysIn); + } + + /** + * A specialized version of `baseMerge` for arrays and objects which performs + * deep merges and tracks traversed objects enabling objects with circular + * references to be merged. + * + * @private + * @param {Object} object The destination object. + * @param {Object} source The source object. + * @param {string} key The key of the value to merge. + * @param {number} srcIndex The index of `source`. + * @param {Function} mergeFunc The function to merge values. + * @param {Function} [customizer] The function to customize assigned values. + * @param {Object} [stack] Tracks traversed source values and their merged + * counterparts. + */ + function baseMergeDeep(object, source, key, srcIndex, mergeFunc, customizer, stack) { + var objValue = object[key], + srcValue = source[key], + stacked = stack.get(srcValue); + + if (stacked) { + assignMergeValue(object, key, stacked); + return; + } + var newValue = customizer + ? customizer(objValue, srcValue, (key + ''), object, source, stack) + : undefined; + + var isCommon = newValue === undefined; + + if (isCommon) { + var isArr = isArray(srcValue), + isBuff = !isArr && isBuffer(srcValue), + isTyped = !isArr && !isBuff && isTypedArray(srcValue); + + newValue = srcValue; + if (isArr || isBuff || isTyped) { + if (isArray(objValue)) { + newValue = objValue; + } + else if (isArrayLikeObject(objValue)) { + newValue = copyArray(objValue); + } + else if (isBuff) { + isCommon = false; + newValue = cloneBuffer(srcValue, true); + } + else if (isTyped) { + isCommon = false; + newValue = cloneTypedArray(srcValue, true); + } + else { + newValue = []; + } + } + else if (isPlainObject(srcValue) || isArguments(srcValue)) { + newValue = objValue; + if (isArguments(objValue)) { + newValue = toPlainObject(objValue); + } + else if (!isObject(objValue) || (srcIndex && isFunction(objValue))) { + newValue = initCloneObject(srcValue); + } + } + else { + isCommon = false; + } + } + if (isCommon) { + // Recursively merge objects and arrays (susceptible to call stack limits). + stack.set(srcValue, newValue); + mergeFunc(newValue, srcValue, srcIndex, customizer, stack); + stack['delete'](srcValue); + } + assignMergeValue(object, key, newValue); + } + + /** + * The base implementation of `_.nth` which doesn't coerce arguments. + * + * @private + * @param {Array} array The array to query. + * @param {number} n The index of the element to return. + * @returns {*} Returns the nth element of `array`. + */ + function baseNth(array, n) { + var length = array.length; + if (!length) { + return; + } + n += n < 0 ? length : 0; + return isIndex(n, length) ? array[n] : undefined; + } + + /** + * The base implementation of `_.orderBy` without param guards. + * + * @private + * @param {Array|Object} collection The collection to iterate over. + * @param {Function[]|Object[]|string[]} iteratees The iteratees to sort by. + * @param {string[]} orders The sort orders of `iteratees`. + * @returns {Array} Returns the new sorted array. + */ + function baseOrderBy(collection, iteratees, orders) { + var index = -1; + iteratees = arrayMap(iteratees.length ? iteratees : [identity], baseUnary(getIteratee())); + + var result = baseMap(collection, function(value, key, collection) { + var criteria = arrayMap(iteratees, function(iteratee) { + return iteratee(value); + }); + return { 'criteria': criteria, 'index': ++index, 'value': value }; + }); + + return baseSortBy(result, function(object, other) { + return compareMultiple(object, other, orders); + }); + } + + /** + * The base implementation of `_.pick` without support for individual + * property identifiers. + * + * @private + * @param {Object} object The source object. + * @param {string[]} paths The property paths to pick. + * @returns {Object} Returns the new object. + */ + function basePick(object, paths) { + return basePickBy(object, paths, function(value, path) { + return hasIn(object, path); + }); + } + + /** + * The base implementation of `_.pickBy` without support for iteratee shorthands. + * + * @private + * @param {Object} object The source object. + * @param {string[]} paths The property paths to pick. + * @param {Function} predicate The function invoked per property. + * @returns {Object} Returns the new object. + */ + function basePickBy(object, paths, predicate) { + var index = -1, + length = paths.length, + result = {}; + + while (++index < length) { + var path = paths[index], + value = baseGet(object, path); + + if (predicate(value, path)) { + baseSet(result, castPath(path, object), value); + } + } + return result; + } + + /** + * A specialized version of `baseProperty` which supports deep paths. + * + * @private + * @param {Array|string} path The path of the property to get. + * @returns {Function} Returns the new accessor function. + */ + function basePropertyDeep(path) { + return function(object) { + return baseGet(object, path); + }; + } + + /** + * The base implementation of `_.pullAllBy` without support for iteratee + * shorthands. + * + * @private + * @param {Array} array The array to modify. + * @param {Array} values The values to remove. + * @param {Function} [iteratee] The iteratee invoked per element. + * @param {Function} [comparator] The comparator invoked per element. + * @returns {Array} Returns `array`. + */ + function basePullAll(array, values, iteratee, comparator) { + var indexOf = comparator ? baseIndexOfWith : baseIndexOf, + index = -1, + length = values.length, + seen = array; + + if (array === values) { + values = copyArray(values); + } + if (iteratee) { + seen = arrayMap(array, baseUnary(iteratee)); + } + while (++index < length) { + var fromIndex = 0, + value = values[index], + computed = iteratee ? iteratee(value) : value; + + while ((fromIndex = indexOf(seen, computed, fromIndex, comparator)) > -1) { + if (seen !== array) { + splice.call(seen, fromIndex, 1); + } + splice.call(array, fromIndex, 1); + } + } + return array; + } + + /** + * The base implementation of `_.pullAt` without support for individual + * indexes or capturing the removed elements. + * + * @private + * @param {Array} array The array to modify. + * @param {number[]} indexes The indexes of elements to remove. + * @returns {Array} Returns `array`. + */ + function basePullAt(array, indexes) { + var length = array ? indexes.length : 0, + lastIndex = length - 1; + + while (length--) { + var index = indexes[length]; + if (length == lastIndex || index !== previous) { + var previous = index; + if (isIndex(index)) { + splice.call(array, index, 1); + } else { + baseUnset(array, index); + } + } + } + return array; + } + + /** + * The base implementation of `_.random` without support for returning + * floating-point numbers. + * + * @private + * @param {number} lower The lower bound. + * @param {number} upper The upper bound. + * @returns {number} Returns the random number. + */ + function baseRandom(lower, upper) { + return lower + nativeFloor(nativeRandom() * (upper - lower + 1)); + } + + /** + * The base implementation of `_.range` and `_.rangeRight` which doesn't + * coerce arguments. + * + * @private + * @param {number} start The start of the range. + * @param {number} end The end of the range. + * @param {number} step The value to increment or decrement by. + * @param {boolean} [fromRight] Specify iterating from right to left. + * @returns {Array} Returns the range of numbers. + */ + function baseRange(start, end, step, fromRight) { + var index = -1, + length = nativeMax(nativeCeil((end - start) / (step || 1)), 0), + result = Array(length); + + while (length--) { + result[fromRight ? length : ++index] = start; + start += step; + } + return result; + } + + /** + * The base implementation of `_.repeat` which doesn't coerce arguments. + * + * @private + * @param {string} string The string to repeat. + * @param {number} n The number of times to repeat the string. + * @returns {string} Returns the repeated string. + */ + function baseRepeat(string, n) { + var result = ''; + if (!string || n < 1 || n > MAX_SAFE_INTEGER) { + return result; + } + // Leverage the exponentiation by squaring algorithm for a faster repeat. + // See https://en.wikipedia.org/wiki/Exponentiation_by_squaring for more details. + do { + if (n % 2) { + result += string; + } + n = nativeFloor(n / 2); + if (n) { + string += string; + } + } while (n); + + return result; + } + + /** + * The base implementation of `_.rest` which doesn't validate or coerce arguments. + * + * @private + * @param {Function} func The function to apply a rest parameter to. + * @param {number} [start=func.length-1] The start position of the rest parameter. + * @returns {Function} Returns the new function. + */ + function baseRest(func, start) { + return setToString(overRest(func, start, identity), func + ''); + } + + /** + * The base implementation of `_.sample`. + * + * @private + * @param {Array|Object} collection The collection to sample. + * @returns {*} Returns the random element. + */ + function baseSample(collection) { + return arraySample(values(collection)); + } + + /** + * The base implementation of `_.sampleSize` without param guards. + * + * @private + * @param {Array|Object} collection The collection to sample. + * @param {number} n The number of elements to sample. + * @returns {Array} Returns the random elements. + */ + function baseSampleSize(collection, n) { + var array = values(collection); + return shuffleSelf(array, baseClamp(n, 0, array.length)); + } + + /** + * The base implementation of `_.set`. + * + * @private + * @param {Object} object The object to modify. + * @param {Array|string} path The path of the property to set. + * @param {*} value The value to set. + * @param {Function} [customizer] The function to customize path creation. + * @returns {Object} Returns `object`. + */ + function baseSet(object, path, value, customizer) { + if (!isObject(object)) { + return object; + } + path = castPath(path, object); + + var index = -1, + length = path.length, + lastIndex = length - 1, + nested = object; + + while (nested != null && ++index < length) { + var key = toKey(path[index]), + newValue = value; + + if (index != lastIndex) { + var objValue = nested[key]; + newValue = customizer ? customizer(objValue, key, nested) : undefined; + if (newValue === undefined) { + newValue = isObject(objValue) + ? objValue + : (isIndex(path[index + 1]) ? [] : {}); + } + } + assignValue(nested, key, newValue); + nested = nested[key]; + } + return object; + } + + /** + * The base implementation of `setData` without support for hot loop shorting. + * + * @private + * @param {Function} func The function to associate metadata with. + * @param {*} data The metadata. + * @returns {Function} Returns `func`. + */ + var baseSetData = !metaMap ? identity : function(func, data) { + metaMap.set(func, data); + return func; + }; + + /** + * The base implementation of `setToString` without support for hot loop shorting. + * + * @private + * @param {Function} func The function to modify. + * @param {Function} string The `toString` result. + * @returns {Function} Returns `func`. + */ + var baseSetToString = !defineProperty ? identity : function(func, string) { + return defineProperty(func, 'toString', { + 'configurable': true, + 'enumerable': false, + 'value': constant(string), + 'writable': true + }); + }; + + /** + * The base implementation of `_.shuffle`. + * + * @private + * @param {Array|Object} collection The collection to shuffle. + * @returns {Array} Returns the new shuffled array. + */ + function baseShuffle(collection) { + return shuffleSelf(values(collection)); + } + + /** + * The base implementation of `_.slice` without an iteratee call guard. + * + * @private + * @param {Array} array The array to slice. + * @param {number} [start=0] The start position. + * @param {number} [end=array.length] The end position. + * @returns {Array} Returns the slice of `array`. + */ + function baseSlice(array, start, end) { + var index = -1, + length = array.length; + + if (start < 0) { + start = -start > length ? 0 : (length + start); + } + end = end > length ? length : end; + if (end < 0) { + end += length; + } + length = start > end ? 0 : ((end - start) >>> 0); + start >>>= 0; + + var result = Array(length); + while (++index < length) { + result[index] = array[index + start]; + } + return result; + } + + /** + * The base implementation of `_.some` without support for iteratee shorthands. + * + * @private + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} predicate The function invoked per iteration. + * @returns {boolean} Returns `true` if any element passes the predicate check, + * else `false`. + */ + function baseSome(collection, predicate) { + var result; + + baseEach(collection, function(value, index, collection) { + result = predicate(value, index, collection); + return !result; + }); + return !!result; + } + + /** + * The base implementation of `_.sortedIndex` and `_.sortedLastIndex` which + * performs a binary search of `array` to determine the index at which `value` + * should be inserted into `array` in order to maintain its sort order. + * + * @private + * @param {Array} array The sorted array to inspect. + * @param {*} value The value to evaluate. + * @param {boolean} [retHighest] Specify returning the highest qualified index. + * @returns {number} Returns the index at which `value` should be inserted + * into `array`. + */ + function baseSortedIndex(array, value, retHighest) { + var low = 0, + high = array == null ? low : array.length; + + if (typeof value == 'number' && value === value && high <= HALF_MAX_ARRAY_LENGTH) { + while (low < high) { + var mid = (low + high) >>> 1, + computed = array[mid]; + + if (computed !== null && !isSymbol(computed) && + (retHighest ? (computed <= value) : (computed < value))) { + low = mid + 1; + } else { + high = mid; + } + } + return high; + } + return baseSortedIndexBy(array, value, identity, retHighest); + } + + /** + * The base implementation of `_.sortedIndexBy` and `_.sortedLastIndexBy` + * which invokes `iteratee` for `value` and each element of `array` to compute + * their sort ranking. The iteratee is invoked with one argument; (value). + * + * @private + * @param {Array} array The sorted array to inspect. + * @param {*} value The value to evaluate. + * @param {Function} iteratee The iteratee invoked per element. + * @param {boolean} [retHighest] Specify returning the highest qualified index. + * @returns {number} Returns the index at which `value` should be inserted + * into `array`. + */ + function baseSortedIndexBy(array, value, iteratee, retHighest) { + value = iteratee(value); + + var low = 0, + high = array == null ? 0 : array.length, + valIsNaN = value !== value, + valIsNull = value === null, + valIsSymbol = isSymbol(value), + valIsUndefined = value === undefined; + + while (low < high) { + var mid = nativeFloor((low + high) / 2), + computed = iteratee(array[mid]), + othIsDefined = computed !== undefined, + othIsNull = computed === null, + othIsReflexive = computed === computed, + othIsSymbol = isSymbol(computed); + + if (valIsNaN) { + var setLow = retHighest || othIsReflexive; + } else if (valIsUndefined) { + setLow = othIsReflexive && (retHighest || othIsDefined); + } else if (valIsNull) { + setLow = othIsReflexive && othIsDefined && (retHighest || !othIsNull); + } else if (valIsSymbol) { + setLow = othIsReflexive && othIsDefined && !othIsNull && (retHighest || !othIsSymbol); + } else if (othIsNull || othIsSymbol) { + setLow = false; + } else { + setLow = retHighest ? (computed <= value) : (computed < value); + } + if (setLow) { + low = mid + 1; + } else { + high = mid; + } + } + return nativeMin(high, MAX_ARRAY_INDEX); + } + + /** + * The base implementation of `_.sortedUniq` and `_.sortedUniqBy` without + * support for iteratee shorthands. + * + * @private + * @param {Array} array The array to inspect. + * @param {Function} [iteratee] The iteratee invoked per element. + * @returns {Array} Returns the new duplicate free array. + */ + function baseSortedUniq(array, iteratee) { + var index = -1, + length = array.length, + resIndex = 0, + result = []; + + while (++index < length) { + var value = array[index], + computed = iteratee ? iteratee(value) : value; + + if (!index || !eq(computed, seen)) { + var seen = computed; + result[resIndex++] = value === 0 ? 0 : value; + } + } + return result; + } + + /** + * The base implementation of `_.toNumber` which doesn't ensure correct + * conversions of binary, hexadecimal, or octal string values. + * + * @private + * @param {*} value The value to process. + * @returns {number} Returns the number. + */ + function baseToNumber(value) { + if (typeof value == 'number') { + return value; + } + if (isSymbol(value)) { + return NAN; + } + return +value; + } + + /** + * The base implementation of `_.toString` which doesn't convert nullish + * values to empty strings. + * + * @private + * @param {*} value The value to process. + * @returns {string} Returns the string. + */ + function baseToString(value) { + // Exit early for strings to avoid a performance hit in some environments. + if (typeof value == 'string') { + return value; + } + if (isArray(value)) { + // Recursively convert values (susceptible to call stack limits). + return arrayMap(value, baseToString) + ''; + } + if (isSymbol(value)) { + return symbolToString ? symbolToString.call(value) : ''; + } + var result = (value + ''); + return (result == '0' && (1 / value) == -INFINITY) ? '-0' : result; + } + + /** + * The base implementation of `_.uniqBy` without support for iteratee shorthands. + * + * @private + * @param {Array} array The array to inspect. + * @param {Function} [iteratee] The iteratee invoked per element. + * @param {Function} [comparator] The comparator invoked per element. + * @returns {Array} Returns the new duplicate free array. + */ + function baseUniq(array, iteratee, comparator) { + var index = -1, + includes = arrayIncludes, + length = array.length, + isCommon = true, + result = [], + seen = result; + + if (comparator) { + isCommon = false; + includes = arrayIncludesWith; + } + else if (length >= LARGE_ARRAY_SIZE) { + var set = iteratee ? null : createSet(array); + if (set) { + return setToArray(set); + } + isCommon = false; + includes = cacheHas; + seen = new SetCache; + } + else { + seen = iteratee ? [] : result; + } + outer: + while (++index < length) { + var value = array[index], + computed = iteratee ? iteratee(value) : value; + + value = (comparator || value !== 0) ? value : 0; + if (isCommon && computed === computed) { + var seenIndex = seen.length; + while (seenIndex--) { + if (seen[seenIndex] === computed) { + continue outer; + } + } + if (iteratee) { + seen.push(computed); + } + result.push(value); + } + else if (!includes(seen, computed, comparator)) { + if (seen !== result) { + seen.push(computed); + } + result.push(value); + } + } + return result; + } + + /** + * The base implementation of `_.unset`. + * + * @private + * @param {Object} object The object to modify. + * @param {Array|string} path The property path to unset. + * @returns {boolean} Returns `true` if the property is deleted, else `false`. + */ + function baseUnset(object, path) { + path = castPath(path, object); + object = parent(object, path); + return object == null || delete object[toKey(last(path))]; + } + + /** + * The base implementation of `_.update`. + * + * @private + * @param {Object} object The object to modify. + * @param {Array|string} path The path of the property to update. + * @param {Function} updater The function to produce the updated value. + * @param {Function} [customizer] The function to customize path creation. + * @returns {Object} Returns `object`. + */ + function baseUpdate(object, path, updater, customizer) { + return baseSet(object, path, updater(baseGet(object, path)), customizer); + } + + /** + * The base implementation of methods like `_.dropWhile` and `_.takeWhile` + * without support for iteratee shorthands. + * + * @private + * @param {Array} array The array to query. + * @param {Function} predicate The function invoked per iteration. + * @param {boolean} [isDrop] Specify dropping elements instead of taking them. + * @param {boolean} [fromRight] Specify iterating from right to left. + * @returns {Array} Returns the slice of `array`. + */ + function baseWhile(array, predicate, isDrop, fromRight) { + var length = array.length, + index = fromRight ? length : -1; + + while ((fromRight ? index-- : ++index < length) && + predicate(array[index], index, array)) {} + + return isDrop + ? baseSlice(array, (fromRight ? 0 : index), (fromRight ? index + 1 : length)) + : baseSlice(array, (fromRight ? index + 1 : 0), (fromRight ? length : index)); + } + + /** + * The base implementation of `wrapperValue` which returns the result of + * performing a sequence of actions on the unwrapped `value`, where each + * successive action is supplied the return value of the previous. + * + * @private + * @param {*} value The unwrapped value. + * @param {Array} actions Actions to perform to resolve the unwrapped value. + * @returns {*} Returns the resolved value. + */ + function baseWrapperValue(value, actions) { + var result = value; + if (result instanceof LazyWrapper) { + result = result.value(); + } + return arrayReduce(actions, function(result, action) { + return action.func.apply(action.thisArg, arrayPush([result], action.args)); + }, result); + } + + /** + * The base implementation of methods like `_.xor`, without support for + * iteratee shorthands, that accepts an array of arrays to inspect. + * + * @private + * @param {Array} arrays The arrays to inspect. + * @param {Function} [iteratee] The iteratee invoked per element. + * @param {Function} [comparator] The comparator invoked per element. + * @returns {Array} Returns the new array of values. + */ + function baseXor(arrays, iteratee, comparator) { + var length = arrays.length; + if (length < 2) { + return length ? baseUniq(arrays[0]) : []; + } + var index = -1, + result = Array(length); + + while (++index < length) { + var array = arrays[index], + othIndex = -1; + + while (++othIndex < length) { + if (othIndex != index) { + result[index] = baseDifference(result[index] || array, arrays[othIndex], iteratee, comparator); + } + } + } + return baseUniq(baseFlatten(result, 1), iteratee, comparator); + } + + /** + * This base implementation of `_.zipObject` which assigns values using `assignFunc`. + * + * @private + * @param {Array} props The property identifiers. + * @param {Array} values The property values. + * @param {Function} assignFunc The function to assign values. + * @returns {Object} Returns the new object. + */ + function baseZipObject(props, values, assignFunc) { + var index = -1, + length = props.length, + valsLength = values.length, + result = {}; + + while (++index < length) { + var value = index < valsLength ? values[index] : undefined; + assignFunc(result, props[index], value); + } + return result; + } + + /** + * Casts `value` to an empty array if it's not an array like object. + * + * @private + * @param {*} value The value to inspect. + * @returns {Array|Object} Returns the cast array-like object. + */ + function castArrayLikeObject(value) { + return isArrayLikeObject(value) ? value : []; + } + + /** + * Casts `value` to `identity` if it's not a function. + * + * @private + * @param {*} value The value to inspect. + * @returns {Function} Returns cast function. + */ + function castFunction(value) { + return typeof value == 'function' ? value : identity; + } + + /** + * Casts `value` to a path array if it's not one. + * + * @private + * @param {*} value The value to inspect. + * @param {Object} [object] The object to query keys on. + * @returns {Array} Returns the cast property path array. + */ + function castPath(value, object) { + if (isArray(value)) { + return value; + } + return isKey(value, object) ? [value] : stringToPath(toString(value)); + } + + /** + * A `baseRest` alias which can be replaced with `identity` by module + * replacement plugins. + * + * @private + * @type {Function} + * @param {Function} func The function to apply a rest parameter to. + * @returns {Function} Returns the new function. + */ + var castRest = baseRest; + + /** + * Casts `array` to a slice if it's needed. + * + * @private + * @param {Array} array The array to inspect. + * @param {number} start The start position. + * @param {number} [end=array.length] The end position. + * @returns {Array} Returns the cast slice. + */ + function castSlice(array, start, end) { + var length = array.length; + end = end === undefined ? length : end; + return (!start && end >= length) ? array : baseSlice(array, start, end); + } + + /** + * A simple wrapper around the global [`clearTimeout`](https://mdn.io/clearTimeout). + * + * @private + * @param {number|Object} id The timer id or timeout object of the timer to clear. + */ + var clearTimeout = ctxClearTimeout || function(id) { + return root.clearTimeout(id); + }; + + /** + * Creates a clone of `buffer`. + * + * @private + * @param {Buffer} buffer The buffer to clone. + * @param {boolean} [isDeep] Specify a deep clone. + * @returns {Buffer} Returns the cloned buffer. + */ + function cloneBuffer(buffer, isDeep) { + if (isDeep) { + return buffer.slice(); + } + var length = buffer.length, + result = allocUnsafe ? allocUnsafe(length) : new buffer.constructor(length); + + buffer.copy(result); + return result; + } + + /** + * Creates a clone of `arrayBuffer`. + * + * @private + * @param {ArrayBuffer} arrayBuffer The array buffer to clone. + * @returns {ArrayBuffer} Returns the cloned array buffer. + */ + function cloneArrayBuffer(arrayBuffer) { + var result = new arrayBuffer.constructor(arrayBuffer.byteLength); + new Uint8Array(result).set(new Uint8Array(arrayBuffer)); + return result; + } + + /** + * Creates a clone of `dataView`. + * + * @private + * @param {Object} dataView The data view to clone. + * @param {boolean} [isDeep] Specify a deep clone. + * @returns {Object} Returns the cloned data view. + */ + function cloneDataView(dataView, isDeep) { + var buffer = isDeep ? cloneArrayBuffer(dataView.buffer) : dataView.buffer; + return new dataView.constructor(buffer, dataView.byteOffset, dataView.byteLength); + } + + /** + * Creates a clone of `map`. + * + * @private + * @param {Object} map The map to clone. + * @param {Function} cloneFunc The function to clone values. + * @param {boolean} [isDeep] Specify a deep clone. + * @returns {Object} Returns the cloned map. + */ + function cloneMap(map, isDeep, cloneFunc) { + var array = isDeep ? cloneFunc(mapToArray(map), CLONE_DEEP_FLAG) : mapToArray(map); + return arrayReduce(array, addMapEntry, new map.constructor); + } + + /** + * Creates a clone of `regexp`. + * + * @private + * @param {Object} regexp The regexp to clone. + * @returns {Object} Returns the cloned regexp. + */ + function cloneRegExp(regexp) { + var result = new regexp.constructor(regexp.source, reFlags.exec(regexp)); + result.lastIndex = regexp.lastIndex; + return result; + } + + /** + * Creates a clone of `set`. + * + * @private + * @param {Object} set The set to clone. + * @param {Function} cloneFunc The function to clone values. + * @param {boolean} [isDeep] Specify a deep clone. + * @returns {Object} Returns the cloned set. + */ + function cloneSet(set, isDeep, cloneFunc) { + var array = isDeep ? cloneFunc(setToArray(set), CLONE_DEEP_FLAG) : setToArray(set); + return arrayReduce(array, addSetEntry, new set.constructor); + } + + /** + * Creates a clone of the `symbol` object. + * + * @private + * @param {Object} symbol The symbol object to clone. + * @returns {Object} Returns the cloned symbol object. + */ + function cloneSymbol(symbol) { + return symbolValueOf ? Object(symbolValueOf.call(symbol)) : {}; + } + + /** + * Creates a clone of `typedArray`. + * + * @private + * @param {Object} typedArray The typed array to clone. + * @param {boolean} [isDeep] Specify a deep clone. + * @returns {Object} Returns the cloned typed array. + */ + function cloneTypedArray(typedArray, isDeep) { + var buffer = isDeep ? cloneArrayBuffer(typedArray.buffer) : typedArray.buffer; + return new typedArray.constructor(buffer, typedArray.byteOffset, typedArray.length); + } + + /** + * Compares values to sort them in ascending order. + * + * @private + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @returns {number} Returns the sort order indicator for `value`. + */ + function compareAscending(value, other) { + if (value !== other) { + var valIsDefined = value !== undefined, + valIsNull = value === null, + valIsReflexive = value === value, + valIsSymbol = isSymbol(value); + + var othIsDefined = other !== undefined, + othIsNull = other === null, + othIsReflexive = other === other, + othIsSymbol = isSymbol(other); + + if ((!othIsNull && !othIsSymbol && !valIsSymbol && value > other) || + (valIsSymbol && othIsDefined && othIsReflexive && !othIsNull && !othIsSymbol) || + (valIsNull && othIsDefined && othIsReflexive) || + (!valIsDefined && othIsReflexive) || + !valIsReflexive) { + return 1; + } + if ((!valIsNull && !valIsSymbol && !othIsSymbol && value < other) || + (othIsSymbol && valIsDefined && valIsReflexive && !valIsNull && !valIsSymbol) || + (othIsNull && valIsDefined && valIsReflexive) || + (!othIsDefined && valIsReflexive) || + !othIsReflexive) { + return -1; + } + } + return 0; + } + + /** + * Used by `_.orderBy` to compare multiple properties of a value to another + * and stable sort them. + * + * If `orders` is unspecified, all values are sorted in ascending order. Otherwise, + * specify an order of "desc" for descending or "asc" for ascending sort order + * of corresponding values. + * + * @private + * @param {Object} object The object to compare. + * @param {Object} other The other object to compare. + * @param {boolean[]|string[]} orders The order to sort by for each property. + * @returns {number} Returns the sort order indicator for `object`. + */ + function compareMultiple(object, other, orders) { + var index = -1, + objCriteria = object.criteria, + othCriteria = other.criteria, + length = objCriteria.length, + ordersLength = orders.length; + + while (++index < length) { + var result = compareAscending(objCriteria[index], othCriteria[index]); + if (result) { + if (index >= ordersLength) { + return result; + } + var order = orders[index]; + return result * (order == 'desc' ? -1 : 1); + } + } + // Fixes an `Array#sort` bug in the JS engine embedded in Adobe applications + // that causes it, under certain circumstances, to provide the same value for + // `object` and `other`. See https://github.com/jashkenas/underscore/pull/1247 + // for more details. + // + // This also ensures a stable sort in V8 and other engines. + // See https://bugs.chromium.org/p/v8/issues/detail?id=90 for more details. + return object.index - other.index; + } + + /** + * Creates an array that is the composition of partially applied arguments, + * placeholders, and provided arguments into a single array of arguments. + * + * @private + * @param {Array} args The provided arguments. + * @param {Array} partials The arguments to prepend to those provided. + * @param {Array} holders The `partials` placeholder indexes. + * @params {boolean} [isCurried] Specify composing for a curried function. + * @returns {Array} Returns the new array of composed arguments. + */ + function composeArgs(args, partials, holders, isCurried) { + var argsIndex = -1, + argsLength = args.length, + holdersLength = holders.length, + leftIndex = -1, + leftLength = partials.length, + rangeLength = nativeMax(argsLength - holdersLength, 0), + result = Array(leftLength + rangeLength), + isUncurried = !isCurried; + + while (++leftIndex < leftLength) { + result[leftIndex] = partials[leftIndex]; + } + while (++argsIndex < holdersLength) { + if (isUncurried || argsIndex < argsLength) { + result[holders[argsIndex]] = args[argsIndex]; + } + } + while (rangeLength--) { + result[leftIndex++] = args[argsIndex++]; + } + return result; + } + + /** + * This function is like `composeArgs` except that the arguments composition + * is tailored for `_.partialRight`. + * + * @private + * @param {Array} args The provided arguments. + * @param {Array} partials The arguments to append to those provided. + * @param {Array} holders The `partials` placeholder indexes. + * @params {boolean} [isCurried] Specify composing for a curried function. + * @returns {Array} Returns the new array of composed arguments. + */ + function composeArgsRight(args, partials, holders, isCurried) { + var argsIndex = -1, + argsLength = args.length, + holdersIndex = -1, + holdersLength = holders.length, + rightIndex = -1, + rightLength = partials.length, + rangeLength = nativeMax(argsLength - holdersLength, 0), + result = Array(rangeLength + rightLength), + isUncurried = !isCurried; + + while (++argsIndex < rangeLength) { + result[argsIndex] = args[argsIndex]; + } + var offset = argsIndex; + while (++rightIndex < rightLength) { + result[offset + rightIndex] = partials[rightIndex]; + } + while (++holdersIndex < holdersLength) { + if (isUncurried || argsIndex < argsLength) { + result[offset + holders[holdersIndex]] = args[argsIndex++]; + } + } + return result; + } + + /** + * Copies the values of `source` to `array`. + * + * @private + * @param {Array} source The array to copy values from. + * @param {Array} [array=[]] The array to copy values to. + * @returns {Array} Returns `array`. + */ + function copyArray(source, array) { + var index = -1, + length = source.length; + + array || (array = Array(length)); + while (++index < length) { + array[index] = source[index]; + } + return array; + } + + /** + * Copies properties of `source` to `object`. + * + * @private + * @param {Object} source The object to copy properties from. + * @param {Array} props The property identifiers to copy. + * @param {Object} [object={}] The object to copy properties to. + * @param {Function} [customizer] The function to customize copied values. + * @returns {Object} Returns `object`. + */ + function copyObject(source, props, object, customizer) { + var isNew = !object; + object || (object = {}); + + var index = -1, + length = props.length; + + while (++index < length) { + var key = props[index]; + + var newValue = customizer + ? customizer(object[key], source[key], key, object, source) + : undefined; + + if (newValue === undefined) { + newValue = source[key]; + } + if (isNew) { + baseAssignValue(object, key, newValue); + } else { + assignValue(object, key, newValue); + } + } + return object; + } + + /** + * Copies own symbols of `source` to `object`. + * + * @private + * @param {Object} source The object to copy symbols from. + * @param {Object} [object={}] The object to copy symbols to. + * @returns {Object} Returns `object`. + */ + function copySymbols(source, object) { + return copyObject(source, getSymbols(source), object); + } + + /** + * Copies own and inherited symbols of `source` to `object`. + * + * @private + * @param {Object} source The object to copy symbols from. + * @param {Object} [object={}] The object to copy symbols to. + * @returns {Object} Returns `object`. + */ + function copySymbolsIn(source, object) { + return copyObject(source, getSymbolsIn(source), object); + } + + /** + * Creates a function like `_.groupBy`. + * + * @private + * @param {Function} setter The function to set accumulator values. + * @param {Function} [initializer] The accumulator object initializer. + * @returns {Function} Returns the new aggregator function. + */ + function createAggregator(setter, initializer) { + return function(collection, iteratee) { + var func = isArray(collection) ? arrayAggregator : baseAggregator, + accumulator = initializer ? initializer() : {}; + + return func(collection, setter, getIteratee(iteratee, 2), accumulator); + }; + } + + /** + * Creates a function like `_.assign`. + * + * @private + * @param {Function} assigner The function to assign values. + * @returns {Function} Returns the new assigner function. + */ + function createAssigner(assigner) { + return baseRest(function(object, sources) { + var index = -1, + length = sources.length, + customizer = length > 1 ? sources[length - 1] : undefined, + guard = length > 2 ? sources[2] : undefined; + + customizer = (assigner.length > 3 && typeof customizer == 'function') + ? (length--, customizer) + : undefined; + + if (guard && isIterateeCall(sources[0], sources[1], guard)) { + customizer = length < 3 ? undefined : customizer; + length = 1; + } + object = Object(object); + while (++index < length) { + var source = sources[index]; + if (source) { + assigner(object, source, index, customizer); + } + } + return object; + }); + } + + /** + * Creates a `baseEach` or `baseEachRight` function. + * + * @private + * @param {Function} eachFunc The function to iterate over a collection. + * @param {boolean} [fromRight] Specify iterating from right to left. + * @returns {Function} Returns the new base function. + */ + function createBaseEach(eachFunc, fromRight) { + return function(collection, iteratee) { + if (collection == null) { + return collection; + } + if (!isArrayLike(collection)) { + return eachFunc(collection, iteratee); + } + var length = collection.length, + index = fromRight ? length : -1, + iterable = Object(collection); + + while ((fromRight ? index-- : ++index < length)) { + if (iteratee(iterable[index], index, iterable) === false) { + break; + } + } + return collection; + }; + } + + /** + * Creates a base function for methods like `_.forIn` and `_.forOwn`. + * + * @private + * @param {boolean} [fromRight] Specify iterating from right to left. + * @returns {Function} Returns the new base function. + */ + function createBaseFor(fromRight) { + return function(object, iteratee, keysFunc) { + var index = -1, + iterable = Object(object), + props = keysFunc(object), + length = props.length; + + while (length--) { + var key = props[fromRight ? length : ++index]; + if (iteratee(iterable[key], key, iterable) === false) { + break; + } + } + return object; + }; + } + + /** + * Creates a function that wraps `func` to invoke it with the optional `this` + * binding of `thisArg`. + * + * @private + * @param {Function} func The function to wrap. + * @param {number} bitmask The bitmask flags. See `createWrap` for more details. + * @param {*} [thisArg] The `this` binding of `func`. + * @returns {Function} Returns the new wrapped function. + */ + function createBind(func, bitmask, thisArg) { + var isBind = bitmask & WRAP_BIND_FLAG, + Ctor = createCtor(func); + + function wrapper() { + var fn = (this && this !== root && this instanceof wrapper) ? Ctor : func; + return fn.apply(isBind ? thisArg : this, arguments); + } + return wrapper; + } + + /** + * Creates a function like `_.lowerFirst`. + * + * @private + * @param {string} methodName The name of the `String` case method to use. + * @returns {Function} Returns the new case function. + */ + function createCaseFirst(methodName) { + return function(string) { + string = toString(string); + + var strSymbols = hasUnicode(string) + ? stringToArray(string) + : undefined; + + var chr = strSymbols + ? strSymbols[0] + : string.charAt(0); + + var trailing = strSymbols + ? castSlice(strSymbols, 1).join('') + : string.slice(1); + + return chr[methodName]() + trailing; + }; + } + + /** + * Creates a function like `_.camelCase`. + * + * @private + * @param {Function} callback The function to combine each word. + * @returns {Function} Returns the new compounder function. + */ + function createCompounder(callback) { + return function(string) { + return arrayReduce(words(deburr(string).replace(reApos, '')), callback, ''); + }; + } + + /** + * Creates a function that produces an instance of `Ctor` regardless of + * whether it was invoked as part of a `new` expression or by `call` or `apply`. + * + * @private + * @param {Function} Ctor The constructor to wrap. + * @returns {Function} Returns the new wrapped function. + */ + function createCtor(Ctor) { + return function() { + // Use a `switch` statement to work with class constructors. See + // http://ecma-international.org/ecma-262/7.0/#sec-ecmascript-function-objects-call-thisargument-argumentslist + // for more details. + var args = arguments; + switch (args.length) { + case 0: return new Ctor; + case 1: return new Ctor(args[0]); + case 2: return new Ctor(args[0], args[1]); + case 3: return new Ctor(args[0], args[1], args[2]); + case 4: return new Ctor(args[0], args[1], args[2], args[3]); + case 5: return new Ctor(args[0], args[1], args[2], args[3], args[4]); + case 6: return new Ctor(args[0], args[1], args[2], args[3], args[4], args[5]); + case 7: return new Ctor(args[0], args[1], args[2], args[3], args[4], args[5], args[6]); + } + var thisBinding = baseCreate(Ctor.prototype), + result = Ctor.apply(thisBinding, args); + + // Mimic the constructor's `return` behavior. + // See https://es5.github.io/#x13.2.2 for more details. + return isObject(result) ? result : thisBinding; + }; + } + + /** + * Creates a function that wraps `func` to enable currying. + * + * @private + * @param {Function} func The function to wrap. + * @param {number} bitmask The bitmask flags. See `createWrap` for more details. + * @param {number} arity The arity of `func`. + * @returns {Function} Returns the new wrapped function. + */ + function createCurry(func, bitmask, arity) { + var Ctor = createCtor(func); + + function wrapper() { + var length = arguments.length, + args = Array(length), + index = length, + placeholder = getHolder(wrapper); + + while (index--) { + args[index] = arguments[index]; + } + var holders = (length < 3 && args[0] !== placeholder && args[length - 1] !== placeholder) + ? [] + : replaceHolders(args, placeholder); + + length -= holders.length; + if (length < arity) { + return createRecurry( + func, bitmask, createHybrid, wrapper.placeholder, undefined, + args, holders, undefined, undefined, arity - length); + } + var fn = (this && this !== root && this instanceof wrapper) ? Ctor : func; + return apply(fn, this, args); + } + return wrapper; + } + + /** + * Creates a `_.find` or `_.findLast` function. + * + * @private + * @param {Function} findIndexFunc The function to find the collection index. + * @returns {Function} Returns the new find function. + */ + function createFind(findIndexFunc) { + return function(collection, predicate, fromIndex) { + var iterable = Object(collection); + if (!isArrayLike(collection)) { + var iteratee = getIteratee(predicate, 3); + collection = keys(collection); + predicate = function(key) { return iteratee(iterable[key], key, iterable); }; + } + var index = findIndexFunc(collection, predicate, fromIndex); + return index > -1 ? iterable[iteratee ? collection[index] : index] : undefined; + }; + } + + /** + * Creates a `_.flow` or `_.flowRight` function. + * + * @private + * @param {boolean} [fromRight] Specify iterating from right to left. + * @returns {Function} Returns the new flow function. + */ + function createFlow(fromRight) { + return flatRest(function(funcs) { + var length = funcs.length, + index = length, + prereq = LodashWrapper.prototype.thru; + + if (fromRight) { + funcs.reverse(); + } + while (index--) { + var func = funcs[index]; + if (typeof func != 'function') { + throw new TypeError(FUNC_ERROR_TEXT); + } + if (prereq && !wrapper && getFuncName(func) == 'wrapper') { + var wrapper = new LodashWrapper([], true); + } + } + index = wrapper ? index : length; + while (++index < length) { + func = funcs[index]; + + var funcName = getFuncName(func), + data = funcName == 'wrapper' ? getData(func) : undefined; + + if (data && isLaziable(data[0]) && + data[1] == (WRAP_ARY_FLAG | WRAP_CURRY_FLAG | WRAP_PARTIAL_FLAG | WRAP_REARG_FLAG) && + !data[4].length && data[9] == 1 + ) { + wrapper = wrapper[getFuncName(data[0])].apply(wrapper, data[3]); + } else { + wrapper = (func.length == 1 && isLaziable(func)) + ? wrapper[funcName]() + : wrapper.thru(func); + } + } + return function() { + var args = arguments, + value = args[0]; + + if (wrapper && args.length == 1 && isArray(value)) { + return wrapper.plant(value).value(); + } + var index = 0, + result = length ? funcs[index].apply(this, args) : value; + + while (++index < length) { + result = funcs[index].call(this, result); + } + return result; + }; + }); + } + + /** + * Creates a function that wraps `func` to invoke it with optional `this` + * binding of `thisArg`, partial application, and currying. + * + * @private + * @param {Function|string} func The function or method name to wrap. + * @param {number} bitmask The bitmask flags. See `createWrap` for more details. + * @param {*} [thisArg] The `this` binding of `func`. + * @param {Array} [partials] The arguments to prepend to those provided to + * the new function. + * @param {Array} [holders] The `partials` placeholder indexes. + * @param {Array} [partialsRight] The arguments to append to those provided + * to the new function. + * @param {Array} [holdersRight] The `partialsRight` placeholder indexes. + * @param {Array} [argPos] The argument positions of the new function. + * @param {number} [ary] The arity cap of `func`. + * @param {number} [arity] The arity of `func`. + * @returns {Function} Returns the new wrapped function. + */ + function createHybrid(func, bitmask, thisArg, partials, holders, partialsRight, holdersRight, argPos, ary, arity) { + var isAry = bitmask & WRAP_ARY_FLAG, + isBind = bitmask & WRAP_BIND_FLAG, + isBindKey = bitmask & WRAP_BIND_KEY_FLAG, + isCurried = bitmask & (WRAP_CURRY_FLAG | WRAP_CURRY_RIGHT_FLAG), + isFlip = bitmask & WRAP_FLIP_FLAG, + Ctor = isBindKey ? undefined : createCtor(func); + + function wrapper() { + var length = arguments.length, + args = Array(length), + index = length; + + while (index--) { + args[index] = arguments[index]; + } + if (isCurried) { + var placeholder = getHolder(wrapper), + holdersCount = countHolders(args, placeholder); + } + if (partials) { + args = composeArgs(args, partials, holders, isCurried); + } + if (partialsRight) { + args = composeArgsRight(args, partialsRight, holdersRight, isCurried); + } + length -= holdersCount; + if (isCurried && length < arity) { + var newHolders = replaceHolders(args, placeholder); + return createRecurry( + func, bitmask, createHybrid, wrapper.placeholder, thisArg, + args, newHolders, argPos, ary, arity - length + ); + } + var thisBinding = isBind ? thisArg : this, + fn = isBindKey ? thisBinding[func] : func; + + length = args.length; + if (argPos) { + args = reorder(args, argPos); + } else if (isFlip && length > 1) { + args.reverse(); + } + if (isAry && ary < length) { + args.length = ary; + } + if (this && this !== root && this instanceof wrapper) { + fn = Ctor || createCtor(fn); + } + return fn.apply(thisBinding, args); + } + return wrapper; + } + + /** + * Creates a function like `_.invertBy`. + * + * @private + * @param {Function} setter The function to set accumulator values. + * @param {Function} toIteratee The function to resolve iteratees. + * @returns {Function} Returns the new inverter function. + */ + function createInverter(setter, toIteratee) { + return function(object, iteratee) { + return baseInverter(object, setter, toIteratee(iteratee), {}); + }; + } + + /** + * Creates a function that performs a mathematical operation on two values. + * + * @private + * @param {Function} operator The function to perform the operation. + * @param {number} [defaultValue] The value used for `undefined` arguments. + * @returns {Function} Returns the new mathematical operation function. + */ + function createMathOperation(operator, defaultValue) { + return function(value, other) { + var result; + if (value === undefined && other === undefined) { + return defaultValue; + } + if (value !== undefined) { + result = value; + } + if (other !== undefined) { + if (result === undefined) { + return other; + } + if (typeof value == 'string' || typeof other == 'string') { + value = baseToString(value); + other = baseToString(other); + } else { + value = baseToNumber(value); + other = baseToNumber(other); + } + result = operator(value, other); + } + return result; + }; + } + + /** + * Creates a function like `_.over`. + * + * @private + * @param {Function} arrayFunc The function to iterate over iteratees. + * @returns {Function} Returns the new over function. + */ + function createOver(arrayFunc) { + return flatRest(function(iteratees) { + iteratees = arrayMap(iteratees, baseUnary(getIteratee())); + return baseRest(function(args) { + var thisArg = this; + return arrayFunc(iteratees, function(iteratee) { + return apply(iteratee, thisArg, args); + }); + }); + }); + } + + /** + * Creates the padding for `string` based on `length`. The `chars` string + * is truncated if the number of characters exceeds `length`. + * + * @private + * @param {number} length The padding length. + * @param {string} [chars=' '] The string used as padding. + * @returns {string} Returns the padding for `string`. + */ + function createPadding(length, chars) { + chars = chars === undefined ? ' ' : baseToString(chars); + + var charsLength = chars.length; + if (charsLength < 2) { + return charsLength ? baseRepeat(chars, length) : chars; + } + var result = baseRepeat(chars, nativeCeil(length / stringSize(chars))); + return hasUnicode(chars) + ? castSlice(stringToArray(result), 0, length).join('') + : result.slice(0, length); + } + + /** + * Creates a function that wraps `func` to invoke it with the `this` binding + * of `thisArg` and `partials` prepended to the arguments it receives. + * + * @private + * @param {Function} func The function to wrap. + * @param {number} bitmask The bitmask flags. See `createWrap` for more details. + * @param {*} thisArg The `this` binding of `func`. + * @param {Array} partials The arguments to prepend to those provided to + * the new function. + * @returns {Function} Returns the new wrapped function. + */ + function createPartial(func, bitmask, thisArg, partials) { + var isBind = bitmask & WRAP_BIND_FLAG, + Ctor = createCtor(func); + + function wrapper() { + var argsIndex = -1, + argsLength = arguments.length, + leftIndex = -1, + leftLength = partials.length, + args = Array(leftLength + argsLength), + fn = (this && this !== root && this instanceof wrapper) ? Ctor : func; + + while (++leftIndex < leftLength) { + args[leftIndex] = partials[leftIndex]; + } + while (argsLength--) { + args[leftIndex++] = arguments[++argsIndex]; + } + return apply(fn, isBind ? thisArg : this, args); + } + return wrapper; + } + + /** + * Creates a `_.range` or `_.rangeRight` function. + * + * @private + * @param {boolean} [fromRight] Specify iterating from right to left. + * @returns {Function} Returns the new range function. + */ + function createRange(fromRight) { + return function(start, end, step) { + if (step && typeof step != 'number' && isIterateeCall(start, end, step)) { + end = step = undefined; + } + // Ensure the sign of `-0` is preserved. + start = toFinite(start); + if (end === undefined) { + end = start; + start = 0; + } else { + end = toFinite(end); + } + step = step === undefined ? (start < end ? 1 : -1) : toFinite(step); + return baseRange(start, end, step, fromRight); + }; + } + + /** + * Creates a function that performs a relational operation on two values. + * + * @private + * @param {Function} operator The function to perform the operation. + * @returns {Function} Returns the new relational operation function. + */ + function createRelationalOperation(operator) { + return function(value, other) { + if (!(typeof value == 'string' && typeof other == 'string')) { + value = toNumber(value); + other = toNumber(other); + } + return operator(value, other); + }; + } + + /** + * Creates a function that wraps `func` to continue currying. + * + * @private + * @param {Function} func The function to wrap. + * @param {number} bitmask The bitmask flags. See `createWrap` for more details. + * @param {Function} wrapFunc The function to create the `func` wrapper. + * @param {*} placeholder The placeholder value. + * @param {*} [thisArg] The `this` binding of `func`. + * @param {Array} [partials] The arguments to prepend to those provided to + * the new function. + * @param {Array} [holders] The `partials` placeholder indexes. + * @param {Array} [argPos] The argument positions of the new function. + * @param {number} [ary] The arity cap of `func`. + * @param {number} [arity] The arity of `func`. + * @returns {Function} Returns the new wrapped function. + */ + function createRecurry(func, bitmask, wrapFunc, placeholder, thisArg, partials, holders, argPos, ary, arity) { + var isCurry = bitmask & WRAP_CURRY_FLAG, + newHolders = isCurry ? holders : undefined, + newHoldersRight = isCurry ? undefined : holders, + newPartials = isCurry ? partials : undefined, + newPartialsRight = isCurry ? undefined : partials; + + bitmask |= (isCurry ? WRAP_PARTIAL_FLAG : WRAP_PARTIAL_RIGHT_FLAG); + bitmask &= ~(isCurry ? WRAP_PARTIAL_RIGHT_FLAG : WRAP_PARTIAL_FLAG); + + if (!(bitmask & WRAP_CURRY_BOUND_FLAG)) { + bitmask &= ~(WRAP_BIND_FLAG | WRAP_BIND_KEY_FLAG); + } + var newData = [ + func, bitmask, thisArg, newPartials, newHolders, newPartialsRight, + newHoldersRight, argPos, ary, arity + ]; + + var result = wrapFunc.apply(undefined, newData); + if (isLaziable(func)) { + setData(result, newData); + } + result.placeholder = placeholder; + return setWrapToString(result, func, bitmask); + } + + /** + * Creates a function like `_.round`. + * + * @private + * @param {string} methodName The name of the `Math` method to use when rounding. + * @returns {Function} Returns the new round function. + */ + function createRound(methodName) { + var func = Math[methodName]; + return function(number, precision) { + number = toNumber(number); + precision = precision == null ? 0 : nativeMin(toInteger(precision), 292); + if (precision) { + // Shift with exponential notation to avoid floating-point issues. + // See [MDN](https://mdn.io/round#Examples) for more details. + var pair = (toString(number) + 'e').split('e'), + value = func(pair[0] + 'e' + (+pair[1] + precision)); + + pair = (toString(value) + 'e').split('e'); + return +(pair[0] + 'e' + (+pair[1] - precision)); + } + return func(number); + }; + } + + /** + * Creates a set object of `values`. + * + * @private + * @param {Array} values The values to add to the set. + * @returns {Object} Returns the new set. + */ + var createSet = !(Set && (1 / setToArray(new Set([,-0]))[1]) == INFINITY) ? noop : function(values) { + return new Set(values); + }; + + /** + * Creates a `_.toPairs` or `_.toPairsIn` function. + * + * @private + * @param {Function} keysFunc The function to get the keys of a given object. + * @returns {Function} Returns the new pairs function. + */ + function createToPairs(keysFunc) { + return function(object) { + var tag = getTag(object); + if (tag == mapTag) { + return mapToArray(object); + } + if (tag == setTag) { + return setToPairs(object); + } + return baseToPairs(object, keysFunc(object)); + }; + } + + /** + * Creates a function that either curries or invokes `func` with optional + * `this` binding and partially applied arguments. + * + * @private + * @param {Function|string} func The function or method name to wrap. + * @param {number} bitmask The bitmask flags. + * 1 - `_.bind` + * 2 - `_.bindKey` + * 4 - `_.curry` or `_.curryRight` of a bound function + * 8 - `_.curry` + * 16 - `_.curryRight` + * 32 - `_.partial` + * 64 - `_.partialRight` + * 128 - `_.rearg` + * 256 - `_.ary` + * 512 - `_.flip` + * @param {*} [thisArg] The `this` binding of `func`. + * @param {Array} [partials] The arguments to be partially applied. + * @param {Array} [holders] The `partials` placeholder indexes. + * @param {Array} [argPos] The argument positions of the new function. + * @param {number} [ary] The arity cap of `func`. + * @param {number} [arity] The arity of `func`. + * @returns {Function} Returns the new wrapped function. + */ + function createWrap(func, bitmask, thisArg, partials, holders, argPos, ary, arity) { + var isBindKey = bitmask & WRAP_BIND_KEY_FLAG; + if (!isBindKey && typeof func != 'function') { + throw new TypeError(FUNC_ERROR_TEXT); + } + var length = partials ? partials.length : 0; + if (!length) { + bitmask &= ~(WRAP_PARTIAL_FLAG | WRAP_PARTIAL_RIGHT_FLAG); + partials = holders = undefined; + } + ary = ary === undefined ? ary : nativeMax(toInteger(ary), 0); + arity = arity === undefined ? arity : toInteger(arity); + length -= holders ? holders.length : 0; + + if (bitmask & WRAP_PARTIAL_RIGHT_FLAG) { + var partialsRight = partials, + holdersRight = holders; + + partials = holders = undefined; + } + var data = isBindKey ? undefined : getData(func); + + var newData = [ + func, bitmask, thisArg, partials, holders, partialsRight, holdersRight, + argPos, ary, arity + ]; + + if (data) { + mergeData(newData, data); + } + func = newData[0]; + bitmask = newData[1]; + thisArg = newData[2]; + partials = newData[3]; + holders = newData[4]; + arity = newData[9] = newData[9] === undefined + ? (isBindKey ? 0 : func.length) + : nativeMax(newData[9] - length, 0); + + if (!arity && bitmask & (WRAP_CURRY_FLAG | WRAP_CURRY_RIGHT_FLAG)) { + bitmask &= ~(WRAP_CURRY_FLAG | WRAP_CURRY_RIGHT_FLAG); + } + if (!bitmask || bitmask == WRAP_BIND_FLAG) { + var result = createBind(func, bitmask, thisArg); + } else if (bitmask == WRAP_CURRY_FLAG || bitmask == WRAP_CURRY_RIGHT_FLAG) { + result = createCurry(func, bitmask, arity); + } else if ((bitmask == WRAP_PARTIAL_FLAG || bitmask == (WRAP_BIND_FLAG | WRAP_PARTIAL_FLAG)) && !holders.length) { + result = createPartial(func, bitmask, thisArg, partials); + } else { + result = createHybrid.apply(undefined, newData); + } + var setter = data ? baseSetData : setData; + return setWrapToString(setter(result, newData), func, bitmask); + } + + /** + * Used by `_.defaults` to customize its `_.assignIn` use to assign properties + * of source objects to the destination object for all destination properties + * that resolve to `undefined`. + * + * @private + * @param {*} objValue The destination value. + * @param {*} srcValue The source value. + * @param {string} key The key of the property to assign. + * @param {Object} object The parent object of `objValue`. + * @returns {*} Returns the value to assign. + */ + function customDefaultsAssignIn(objValue, srcValue, key, object) { + if (objValue === undefined || + (eq(objValue, objectProto[key]) && !hasOwnProperty.call(object, key))) { + return srcValue; + } + return objValue; + } + + /** + * Used by `_.defaultsDeep` to customize its `_.merge` use to merge source + * objects into destination objects that are passed thru. + * + * @private + * @param {*} objValue The destination value. + * @param {*} srcValue The source value. + * @param {string} key The key of the property to merge. + * @param {Object} object The parent object of `objValue`. + * @param {Object} source The parent object of `srcValue`. + * @param {Object} [stack] Tracks traversed source values and their merged + * counterparts. + * @returns {*} Returns the value to assign. + */ + function customDefaultsMerge(objValue, srcValue, key, object, source, stack) { + if (isObject(objValue) && isObject(srcValue)) { + // Recursively merge objects and arrays (susceptible to call stack limits). + stack.set(srcValue, objValue); + baseMerge(objValue, srcValue, undefined, customDefaultsMerge, stack); + stack['delete'](srcValue); + } + return objValue; + } + + /** + * Used by `_.omit` to customize its `_.cloneDeep` use to only clone plain + * objects. + * + * @private + * @param {*} value The value to inspect. + * @param {string} key The key of the property to inspect. + * @returns {*} Returns the uncloned value or `undefined` to defer cloning to `_.cloneDeep`. + */ + function customOmitClone(value) { + return isPlainObject(value) ? undefined : value; + } + + /** + * A specialized version of `baseIsEqualDeep` for arrays with support for + * partial deep comparisons. + * + * @private + * @param {Array} array The array to compare. + * @param {Array} other The other array to compare. + * @param {number} bitmask The bitmask flags. See `baseIsEqual` for more details. + * @param {Function} customizer The function to customize comparisons. + * @param {Function} equalFunc The function to determine equivalents of values. + * @param {Object} stack Tracks traversed `array` and `other` objects. + * @returns {boolean} Returns `true` if the arrays are equivalent, else `false`. + */ + function equalArrays(array, other, bitmask, customizer, equalFunc, stack) { + var isPartial = bitmask & COMPARE_PARTIAL_FLAG, + arrLength = array.length, + othLength = other.length; + + if (arrLength != othLength && !(isPartial && othLength > arrLength)) { + return false; + } + // Assume cyclic values are equal. + var stacked = stack.get(array); + if (stacked && stack.get(other)) { + return stacked == other; + } + var index = -1, + result = true, + seen = (bitmask & COMPARE_UNORDERED_FLAG) ? new SetCache : undefined; + + stack.set(array, other); + stack.set(other, array); + + // Ignore non-index properties. + while (++index < arrLength) { + var arrValue = array[index], + othValue = other[index]; + + if (customizer) { + var compared = isPartial + ? customizer(othValue, arrValue, index, other, array, stack) + : customizer(arrValue, othValue, index, array, other, stack); + } + if (compared !== undefined) { + if (compared) { + continue; + } + result = false; + break; + } + // Recursively compare arrays (susceptible to call stack limits). + if (seen) { + if (!arraySome(other, function(othValue, othIndex) { + if (!cacheHas(seen, othIndex) && + (arrValue === othValue || equalFunc(arrValue, othValue, bitmask, customizer, stack))) { + return seen.push(othIndex); + } + })) { + result = false; + break; + } + } else if (!( + arrValue === othValue || + equalFunc(arrValue, othValue, bitmask, customizer, stack) + )) { + result = false; + break; + } + } + stack['delete'](array); + stack['delete'](other); + return result; + } + + /** + * A specialized version of `baseIsEqualDeep` for comparing objects of + * the same `toStringTag`. + * + * **Note:** This function only supports comparing values with tags of + * `Boolean`, `Date`, `Error`, `Number`, `RegExp`, or `String`. + * + * @private + * @param {Object} object The object to compare. + * @param {Object} other The other object to compare. + * @param {string} tag The `toStringTag` of the objects to compare. + * @param {number} bitmask The bitmask flags. See `baseIsEqual` for more details. + * @param {Function} customizer The function to customize comparisons. + * @param {Function} equalFunc The function to determine equivalents of values. + * @param {Object} stack Tracks traversed `object` and `other` objects. + * @returns {boolean} Returns `true` if the objects are equivalent, else `false`. + */ + function equalByTag(object, other, tag, bitmask, customizer, equalFunc, stack) { + switch (tag) { + case dataViewTag: + if ((object.byteLength != other.byteLength) || + (object.byteOffset != other.byteOffset)) { + return false; + } + object = object.buffer; + other = other.buffer; + + case arrayBufferTag: + if ((object.byteLength != other.byteLength) || + !equalFunc(new Uint8Array(object), new Uint8Array(other))) { + return false; + } + return true; + + case boolTag: + case dateTag: + case numberTag: + // Coerce booleans to `1` or `0` and dates to milliseconds. + // Invalid dates are coerced to `NaN`. + return eq(+object, +other); + + case errorTag: + return object.name == other.name && object.message == other.message; + + case regexpTag: + case stringTag: + // Coerce regexes to strings and treat strings, primitives and objects, + // as equal. See http://www.ecma-international.org/ecma-262/7.0/#sec-regexp.prototype.tostring + // for more details. + return object == (other + ''); + + case mapTag: + var convert = mapToArray; + + case setTag: + var isPartial = bitmask & COMPARE_PARTIAL_FLAG; + convert || (convert = setToArray); + + if (object.size != other.size && !isPartial) { + return false; + } + // Assume cyclic values are equal. + var stacked = stack.get(object); + if (stacked) { + return stacked == other; + } + bitmask |= COMPARE_UNORDERED_FLAG; + + // Recursively compare objects (susceptible to call stack limits). + stack.set(object, other); + var result = equalArrays(convert(object), convert(other), bitmask, customizer, equalFunc, stack); + stack['delete'](object); + return result; + + case symbolTag: + if (symbolValueOf) { + return symbolValueOf.call(object) == symbolValueOf.call(other); + } + } + return false; + } + + /** + * A specialized version of `baseIsEqualDeep` for objects with support for + * partial deep comparisons. + * + * @private + * @param {Object} object The object to compare. + * @param {Object} other The other object to compare. + * @param {number} bitmask The bitmask flags. See `baseIsEqual` for more details. + * @param {Function} customizer The function to customize comparisons. + * @param {Function} equalFunc The function to determine equivalents of values. + * @param {Object} stack Tracks traversed `object` and `other` objects. + * @returns {boolean} Returns `true` if the objects are equivalent, else `false`. + */ + function equalObjects(object, other, bitmask, customizer, equalFunc, stack) { + var isPartial = bitmask & COMPARE_PARTIAL_FLAG, + objProps = getAllKeys(object), + objLength = objProps.length, + othProps = getAllKeys(other), + othLength = othProps.length; + + if (objLength != othLength && !isPartial) { + return false; + } + var index = objLength; + while (index--) { + var key = objProps[index]; + if (!(isPartial ? key in other : hasOwnProperty.call(other, key))) { + return false; + } + } + // Assume cyclic values are equal. + var stacked = stack.get(object); + if (stacked && stack.get(other)) { + return stacked == other; + } + var result = true; + stack.set(object, other); + stack.set(other, object); + + var skipCtor = isPartial; + while (++index < objLength) { + key = objProps[index]; + var objValue = object[key], + othValue = other[key]; + + if (customizer) { + var compared = isPartial + ? customizer(othValue, objValue, key, other, object, stack) + : customizer(objValue, othValue, key, object, other, stack); + } + // Recursively compare objects (susceptible to call stack limits). + if (!(compared === undefined + ? (objValue === othValue || equalFunc(objValue, othValue, bitmask, customizer, stack)) + : compared + )) { + result = false; + break; + } + skipCtor || (skipCtor = key == 'constructor'); + } + if (result && !skipCtor) { + var objCtor = object.constructor, + othCtor = other.constructor; + + // Non `Object` object instances with different constructors are not equal. + if (objCtor != othCtor && + ('constructor' in object && 'constructor' in other) && + !(typeof objCtor == 'function' && objCtor instanceof objCtor && + typeof othCtor == 'function' && othCtor instanceof othCtor)) { + result = false; + } + } + stack['delete'](object); + stack['delete'](other); + return result; + } + + /** + * A specialized version of `baseRest` which flattens the rest array. + * + * @private + * @param {Function} func The function to apply a rest parameter to. + * @returns {Function} Returns the new function. + */ + function flatRest(func) { + return setToString(overRest(func, undefined, flatten), func + ''); + } + + /** + * Creates an array of own enumerable property names and symbols of `object`. + * + * @private + * @param {Object} object The object to query. + * @returns {Array} Returns the array of property names and symbols. + */ + function getAllKeys(object) { + return baseGetAllKeys(object, keys, getSymbols); + } + + /** + * Creates an array of own and inherited enumerable property names and + * symbols of `object`. + * + * @private + * @param {Object} object The object to query. + * @returns {Array} Returns the array of property names and symbols. + */ + function getAllKeysIn(object) { + return baseGetAllKeys(object, keysIn, getSymbolsIn); + } + + /** + * Gets metadata for `func`. + * + * @private + * @param {Function} func The function to query. + * @returns {*} Returns the metadata for `func`. + */ + var getData = !metaMap ? noop : function(func) { + return metaMap.get(func); + }; + + /** + * Gets the name of `func`. + * + * @private + * @param {Function} func The function to query. + * @returns {string} Returns the function name. + */ + function getFuncName(func) { + var result = (func.name + ''), + array = realNames[result], + length = hasOwnProperty.call(realNames, result) ? array.length : 0; + + while (length--) { + var data = array[length], + otherFunc = data.func; + if (otherFunc == null || otherFunc == func) { + return data.name; + } + } + return result; + } + + /** + * Gets the argument placeholder value for `func`. + * + * @private + * @param {Function} func The function to inspect. + * @returns {*} Returns the placeholder value. + */ + function getHolder(func) { + var object = hasOwnProperty.call(lodash, 'placeholder') ? lodash : func; + return object.placeholder; + } + + /** + * Gets the appropriate "iteratee" function. If `_.iteratee` is customized, + * this function returns the custom method, otherwise it returns `baseIteratee`. + * If arguments are provided, the chosen function is invoked with them and + * its result is returned. + * + * @private + * @param {*} [value] The value to convert to an iteratee. + * @param {number} [arity] The arity of the created iteratee. + * @returns {Function} Returns the chosen function or its result. + */ + function getIteratee() { + var result = lodash.iteratee || iteratee; + result = result === iteratee ? baseIteratee : result; + return arguments.length ? result(arguments[0], arguments[1]) : result; + } + + /** + * Gets the data for `map`. + * + * @private + * @param {Object} map The map to query. + * @param {string} key The reference key. + * @returns {*} Returns the map data. + */ + function getMapData(map, key) { + var data = map.__data__; + return isKeyable(key) + ? data[typeof key == 'string' ? 'string' : 'hash'] + : data.map; + } + + /** + * Gets the property names, values, and compare flags of `object`. + * + * @private + * @param {Object} object The object to query. + * @returns {Array} Returns the match data of `object`. + */ + function getMatchData(object) { + var result = keys(object), + length = result.length; + + while (length--) { + var key = result[length], + value = object[key]; + + result[length] = [key, value, isStrictComparable(value)]; + } + return result; + } + + /** + * Gets the native function at `key` of `object`. + * + * @private + * @param {Object} object The object to query. + * @param {string} key The key of the method to get. + * @returns {*} Returns the function if it's native, else `undefined`. + */ + function getNative(object, key) { + var value = getValue(object, key); + return baseIsNative(value) ? value : undefined; + } + + /** + * A specialized version of `baseGetTag` which ignores `Symbol.toStringTag` values. + * + * @private + * @param {*} value The value to query. + * @returns {string} Returns the raw `toStringTag`. + */ + function getRawTag(value) { + var isOwn = hasOwnProperty.call(value, symToStringTag), + tag = value[symToStringTag]; + + try { + value[symToStringTag] = undefined; + var unmasked = true; + } catch (e) {} + + var result = nativeObjectToString.call(value); + if (unmasked) { + if (isOwn) { + value[symToStringTag] = tag; + } else { + delete value[symToStringTag]; + } + } + return result; + } + + /** + * Creates an array of the own enumerable symbols of `object`. + * + * @private + * @param {Object} object The object to query. + * @returns {Array} Returns the array of symbols. + */ + var getSymbols = !nativeGetSymbols ? stubArray : function(object) { + if (object == null) { + return []; + } + object = Object(object); + return arrayFilter(nativeGetSymbols(object), function(symbol) { + return propertyIsEnumerable.call(object, symbol); + }); + }; + + /** + * Creates an array of the own and inherited enumerable symbols of `object`. + * + * @private + * @param {Object} object The object to query. + * @returns {Array} Returns the array of symbols. + */ + var getSymbolsIn = !nativeGetSymbols ? stubArray : function(object) { + var result = []; + while (object) { + arrayPush(result, getSymbols(object)); + object = getPrototype(object); + } + return result; + }; + + /** + * Gets the `toStringTag` of `value`. + * + * @private + * @param {*} value The value to query. + * @returns {string} Returns the `toStringTag`. + */ + var getTag = baseGetTag; + + // Fallback for data views, maps, sets, and weak maps in IE 11 and promises in Node.js < 6. + if ((DataView && getTag(new DataView(new ArrayBuffer(1))) != dataViewTag) || + (Map && getTag(new Map) != mapTag) || + (Promise && getTag(Promise.resolve()) != promiseTag) || + (Set && getTag(new Set) != setTag) || + (WeakMap && getTag(new WeakMap) != weakMapTag)) { + getTag = function(value) { + var result = baseGetTag(value), + Ctor = result == objectTag ? value.constructor : undefined, + ctorString = Ctor ? toSource(Ctor) : ''; + + if (ctorString) { + switch (ctorString) { + case dataViewCtorString: return dataViewTag; + case mapCtorString: return mapTag; + case promiseCtorString: return promiseTag; + case setCtorString: return setTag; + case weakMapCtorString: return weakMapTag; + } + } + return result; + }; + } + + /** + * Gets the view, applying any `transforms` to the `start` and `end` positions. + * + * @private + * @param {number} start The start of the view. + * @param {number} end The end of the view. + * @param {Array} transforms The transformations to apply to the view. + * @returns {Object} Returns an object containing the `start` and `end` + * positions of the view. + */ + function getView(start, end, transforms) { + var index = -1, + length = transforms.length; + + while (++index < length) { + var data = transforms[index], + size = data.size; + + switch (data.type) { + case 'drop': start += size; break; + case 'dropRight': end -= size; break; + case 'take': end = nativeMin(end, start + size); break; + case 'takeRight': start = nativeMax(start, end - size); break; + } + } + return { 'start': start, 'end': end }; + } + + /** + * Extracts wrapper details from the `source` body comment. + * + * @private + * @param {string} source The source to inspect. + * @returns {Array} Returns the wrapper details. + */ + function getWrapDetails(source) { + var match = source.match(reWrapDetails); + return match ? match[1].split(reSplitDetails) : []; + } + + /** + * Checks if `path` exists on `object`. + * + * @private + * @param {Object} object The object to query. + * @param {Array|string} path The path to check. + * @param {Function} hasFunc The function to check properties. + * @returns {boolean} Returns `true` if `path` exists, else `false`. + */ + function hasPath(object, path, hasFunc) { + path = castPath(path, object); + + var index = -1, + length = path.length, + result = false; + + while (++index < length) { + var key = toKey(path[index]); + if (!(result = object != null && hasFunc(object, key))) { + break; + } + object = object[key]; + } + if (result || ++index != length) { + return result; + } + length = object == null ? 0 : object.length; + return !!length && isLength(length) && isIndex(key, length) && + (isArray(object) || isArguments(object)); + } + + /** + * Initializes an array clone. + * + * @private + * @param {Array} array The array to clone. + * @returns {Array} Returns the initialized clone. + */ + function initCloneArray(array) { + var length = array.length, + result = array.constructor(length); + + // Add properties assigned by `RegExp#exec`. + if (length && typeof array[0] == 'string' && hasOwnProperty.call(array, 'index')) { + result.index = array.index; + result.input = array.input; + } + return result; + } + + /** + * Initializes an object clone. + * + * @private + * @param {Object} object The object to clone. + * @returns {Object} Returns the initialized clone. + */ + function initCloneObject(object) { + return (typeof object.constructor == 'function' && !isPrototype(object)) + ? baseCreate(getPrototype(object)) + : {}; + } + + /** + * Initializes an object clone based on its `toStringTag`. + * + * **Note:** This function only supports cloning values with tags of + * `Boolean`, `Date`, `Error`, `Number`, `RegExp`, or `String`. + * + * @private + * @param {Object} object The object to clone. + * @param {string} tag The `toStringTag` of the object to clone. + * @param {Function} cloneFunc The function to clone values. + * @param {boolean} [isDeep] Specify a deep clone. + * @returns {Object} Returns the initialized clone. + */ + function initCloneByTag(object, tag, cloneFunc, isDeep) { + var Ctor = object.constructor; + switch (tag) { + case arrayBufferTag: + return cloneArrayBuffer(object); + + case boolTag: + case dateTag: + return new Ctor(+object); + + case dataViewTag: + return cloneDataView(object, isDeep); + + case float32Tag: case float64Tag: + case int8Tag: case int16Tag: case int32Tag: + case uint8Tag: case uint8ClampedTag: case uint16Tag: case uint32Tag: + return cloneTypedArray(object, isDeep); + + case mapTag: + return cloneMap(object, isDeep, cloneFunc); + + case numberTag: + case stringTag: + return new Ctor(object); + + case regexpTag: + return cloneRegExp(object); + + case setTag: + return cloneSet(object, isDeep, cloneFunc); + + case symbolTag: + return cloneSymbol(object); + } + } + + /** + * Inserts wrapper `details` in a comment at the top of the `source` body. + * + * @private + * @param {string} source The source to modify. + * @returns {Array} details The details to insert. + * @returns {string} Returns the modified source. + */ + function insertWrapDetails(source, details) { + var length = details.length; + if (!length) { + return source; + } + var lastIndex = length - 1; + details[lastIndex] = (length > 1 ? '& ' : '') + details[lastIndex]; + details = details.join(length > 2 ? ', ' : ' '); + return source.replace(reWrapComment, '{\n/* [wrapped with ' + details + '] */\n'); + } + + /** + * Checks if `value` is a flattenable `arguments` object or array. + * + * @private + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is flattenable, else `false`. + */ + function isFlattenable(value) { + return isArray(value) || isArguments(value) || + !!(spreadableSymbol && value && value[spreadableSymbol]); + } + + /** + * Checks if `value` is a valid array-like index. + * + * @private + * @param {*} value The value to check. + * @param {number} [length=MAX_SAFE_INTEGER] The upper bounds of a valid index. + * @returns {boolean} Returns `true` if `value` is a valid index, else `false`. + */ + function isIndex(value, length) { + length = length == null ? MAX_SAFE_INTEGER : length; + return !!length && + (typeof value == 'number' || reIsUint.test(value)) && + (value > -1 && value % 1 == 0 && value < length); + } + + /** + * Checks if the given arguments are from an iteratee call. + * + * @private + * @param {*} value The potential iteratee value argument. + * @param {*} index The potential iteratee index or key argument. + * @param {*} object The potential iteratee object argument. + * @returns {boolean} Returns `true` if the arguments are from an iteratee call, + * else `false`. + */ + function isIterateeCall(value, index, object) { + if (!isObject(object)) { + return false; + } + var type = typeof index; + if (type == 'number' + ? (isArrayLike(object) && isIndex(index, object.length)) + : (type == 'string' && index in object) + ) { + return eq(object[index], value); + } + return false; + } + + /** + * Checks if `value` is a property name and not a property path. + * + * @private + * @param {*} value The value to check. + * @param {Object} [object] The object to query keys on. + * @returns {boolean} Returns `true` if `value` is a property name, else `false`. + */ + function isKey(value, object) { + if (isArray(value)) { + return false; + } + var type = typeof value; + if (type == 'number' || type == 'symbol' || type == 'boolean' || + value == null || isSymbol(value)) { + return true; + } + return reIsPlainProp.test(value) || !reIsDeepProp.test(value) || + (object != null && value in Object(object)); + } + + /** + * Checks if `value` is suitable for use as unique object key. + * + * @private + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is suitable, else `false`. + */ + function isKeyable(value) { + var type = typeof value; + return (type == 'string' || type == 'number' || type == 'symbol' || type == 'boolean') + ? (value !== '__proto__') + : (value === null); + } + + /** + * Checks if `func` has a lazy counterpart. + * + * @private + * @param {Function} func The function to check. + * @returns {boolean} Returns `true` if `func` has a lazy counterpart, + * else `false`. + */ + function isLaziable(func) { + var funcName = getFuncName(func), + other = lodash[funcName]; + + if (typeof other != 'function' || !(funcName in LazyWrapper.prototype)) { + return false; + } + if (func === other) { + return true; + } + var data = getData(other); + return !!data && func === data[0]; + } + + /** + * Checks if `func` has its source masked. + * + * @private + * @param {Function} func The function to check. + * @returns {boolean} Returns `true` if `func` is masked, else `false`. + */ + function isMasked(func) { + return !!maskSrcKey && (maskSrcKey in func); + } + + /** + * Checks if `func` is capable of being masked. + * + * @private + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `func` is maskable, else `false`. + */ + var isMaskable = coreJsData ? isFunction : stubFalse; + + /** + * Checks if `value` is likely a prototype object. + * + * @private + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a prototype, else `false`. + */ + function isPrototype(value) { + var Ctor = value && value.constructor, + proto = (typeof Ctor == 'function' && Ctor.prototype) || objectProto; + + return value === proto; + } + + /** + * Checks if `value` is suitable for strict equality comparisons, i.e. `===`. + * + * @private + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` if suitable for strict + * equality comparisons, else `false`. + */ + function isStrictComparable(value) { + return value === value && !isObject(value); + } + + /** + * A specialized version of `matchesProperty` for source values suitable + * for strict equality comparisons, i.e. `===`. + * + * @private + * @param {string} key The key of the property to get. + * @param {*} srcValue The value to match. + * @returns {Function} Returns the new spec function. + */ + function matchesStrictComparable(key, srcValue) { + return function(object) { + if (object == null) { + return false; + } + return object[key] === srcValue && + (srcValue !== undefined || (key in Object(object))); + }; + } + + /** + * A specialized version of `_.memoize` which clears the memoized function's + * cache when it exceeds `MAX_MEMOIZE_SIZE`. + * + * @private + * @param {Function} func The function to have its output memoized. + * @returns {Function} Returns the new memoized function. + */ + function memoizeCapped(func) { + var result = memoize(func, function(key) { + if (cache.size === MAX_MEMOIZE_SIZE) { + cache.clear(); + } + return key; + }); + + var cache = result.cache; + return result; + } + + /** + * Merges the function metadata of `source` into `data`. + * + * Merging metadata reduces the number of wrappers used to invoke a function. + * This is possible because methods like `_.bind`, `_.curry`, and `_.partial` + * may be applied regardless of execution order. Methods like `_.ary` and + * `_.rearg` modify function arguments, making the order in which they are + * executed important, preventing the merging of metadata. However, we make + * an exception for a safe combined case where curried functions have `_.ary` + * and or `_.rearg` applied. + * + * @private + * @param {Array} data The destination metadata. + * @param {Array} source The source metadata. + * @returns {Array} Returns `data`. + */ + function mergeData(data, source) { + var bitmask = data[1], + srcBitmask = source[1], + newBitmask = bitmask | srcBitmask, + isCommon = newBitmask < (WRAP_BIND_FLAG | WRAP_BIND_KEY_FLAG | WRAP_ARY_FLAG); + + var isCombo = + ((srcBitmask == WRAP_ARY_FLAG) && (bitmask == WRAP_CURRY_FLAG)) || + ((srcBitmask == WRAP_ARY_FLAG) && (bitmask == WRAP_REARG_FLAG) && (data[7].length <= source[8])) || + ((srcBitmask == (WRAP_ARY_FLAG | WRAP_REARG_FLAG)) && (source[7].length <= source[8]) && (bitmask == WRAP_CURRY_FLAG)); + + // Exit early if metadata can't be merged. + if (!(isCommon || isCombo)) { + return data; + } + // Use source `thisArg` if available. + if (srcBitmask & WRAP_BIND_FLAG) { + data[2] = source[2]; + // Set when currying a bound function. + newBitmask |= bitmask & WRAP_BIND_FLAG ? 0 : WRAP_CURRY_BOUND_FLAG; + } + // Compose partial arguments. + var value = source[3]; + if (value) { + var partials = data[3]; + data[3] = partials ? composeArgs(partials, value, source[4]) : value; + data[4] = partials ? replaceHolders(data[3], PLACEHOLDER) : source[4]; + } + // Compose partial right arguments. + value = source[5]; + if (value) { + partials = data[5]; + data[5] = partials ? composeArgsRight(partials, value, source[6]) : value; + data[6] = partials ? replaceHolders(data[5], PLACEHOLDER) : source[6]; + } + // Use source `argPos` if available. + value = source[7]; + if (value) { + data[7] = value; + } + // Use source `ary` if it's smaller. + if (srcBitmask & WRAP_ARY_FLAG) { + data[8] = data[8] == null ? source[8] : nativeMin(data[8], source[8]); + } + // Use source `arity` if one is not provided. + if (data[9] == null) { + data[9] = source[9]; + } + // Use source `func` and merge bitmasks. + data[0] = source[0]; + data[1] = newBitmask; + + return data; + } + + /** + * This function is like + * [`Object.keys`](http://ecma-international.org/ecma-262/7.0/#sec-object.keys) + * except that it includes inherited enumerable properties. + * + * @private + * @param {Object} object The object to query. + * @returns {Array} Returns the array of property names. + */ + function nativeKeysIn(object) { + var result = []; + if (object != null) { + for (var key in Object(object)) { + result.push(key); + } + } + return result; + } + + /** + * Converts `value` to a string using `Object.prototype.toString`. + * + * @private + * @param {*} value The value to convert. + * @returns {string} Returns the converted string. + */ + function objectToString(value) { + return nativeObjectToString.call(value); + } + + /** + * A specialized version of `baseRest` which transforms the rest array. + * + * @private + * @param {Function} func The function to apply a rest parameter to. + * @param {number} [start=func.length-1] The start position of the rest parameter. + * @param {Function} transform The rest array transform. + * @returns {Function} Returns the new function. + */ + function overRest(func, start, transform) { + start = nativeMax(start === undefined ? (func.length - 1) : start, 0); + return function() { + var args = arguments, + index = -1, + length = nativeMax(args.length - start, 0), + array = Array(length); + + while (++index < length) { + array[index] = args[start + index]; + } + index = -1; + var otherArgs = Array(start + 1); + while (++index < start) { + otherArgs[index] = args[index]; + } + otherArgs[start] = transform(array); + return apply(func, this, otherArgs); + }; + } + + /** + * Gets the parent value at `path` of `object`. + * + * @private + * @param {Object} object The object to query. + * @param {Array} path The path to get the parent value of. + * @returns {*} Returns the parent value. + */ + function parent(object, path) { + return path.length < 2 ? object : baseGet(object, baseSlice(path, 0, -1)); + } + + /** + * Reorder `array` according to the specified indexes where the element at + * the first index is assigned as the first element, the element at + * the second index is assigned as the second element, and so on. + * + * @private + * @param {Array} array The array to reorder. + * @param {Array} indexes The arranged array indexes. + * @returns {Array} Returns `array`. + */ + function reorder(array, indexes) { + var arrLength = array.length, + length = nativeMin(indexes.length, arrLength), + oldArray = copyArray(array); + + while (length--) { + var index = indexes[length]; + array[length] = isIndex(index, arrLength) ? oldArray[index] : undefined; + } + return array; + } + + /** + * Sets metadata for `func`. + * + * **Note:** If this function becomes hot, i.e. is invoked a lot in a short + * period of time, it will trip its breaker and transition to an identity + * function to avoid garbage collection pauses in V8. See + * [V8 issue 2070](https://bugs.chromium.org/p/v8/issues/detail?id=2070) + * for more details. + * + * @private + * @param {Function} func The function to associate metadata with. + * @param {*} data The metadata. + * @returns {Function} Returns `func`. + */ + var setData = shortOut(baseSetData); + + /** + * A simple wrapper around the global [`setTimeout`](https://mdn.io/setTimeout). + * + * @private + * @param {Function} func The function to delay. + * @param {number} wait The number of milliseconds to delay invocation. + * @returns {number|Object} Returns the timer id or timeout object. + */ + var setTimeout = ctxSetTimeout || function(func, wait) { + return root.setTimeout(func, wait); + }; + + /** + * Sets the `toString` method of `func` to return `string`. + * + * @private + * @param {Function} func The function to modify. + * @param {Function} string The `toString` result. + * @returns {Function} Returns `func`. + */ + var setToString = shortOut(baseSetToString); + + /** + * Sets the `toString` method of `wrapper` to mimic the source of `reference` + * with wrapper details in a comment at the top of the source body. + * + * @private + * @param {Function} wrapper The function to modify. + * @param {Function} reference The reference function. + * @param {number} bitmask The bitmask flags. See `createWrap` for more details. + * @returns {Function} Returns `wrapper`. + */ + function setWrapToString(wrapper, reference, bitmask) { + var source = (reference + ''); + return setToString(wrapper, insertWrapDetails(source, updateWrapDetails(getWrapDetails(source), bitmask))); + } + + /** + * Creates a function that'll short out and invoke `identity` instead + * of `func` when it's called `HOT_COUNT` or more times in `HOT_SPAN` + * milliseconds. + * + * @private + * @param {Function} func The function to restrict. + * @returns {Function} Returns the new shortable function. + */ + function shortOut(func) { + var count = 0, + lastCalled = 0; + + return function() { + var stamp = nativeNow(), + remaining = HOT_SPAN - (stamp - lastCalled); + + lastCalled = stamp; + if (remaining > 0) { + if (++count >= HOT_COUNT) { + return arguments[0]; + } + } else { + count = 0; + } + return func.apply(undefined, arguments); + }; + } + + /** + * A specialized version of `_.shuffle` which mutates and sets the size of `array`. + * + * @private + * @param {Array} array The array to shuffle. + * @param {number} [size=array.length] The size of `array`. + * @returns {Array} Returns `array`. + */ + function shuffleSelf(array, size) { + var index = -1, + length = array.length, + lastIndex = length - 1; + + size = size === undefined ? length : size; + while (++index < size) { + var rand = baseRandom(index, lastIndex), + value = array[rand]; + + array[rand] = array[index]; + array[index] = value; + } + array.length = size; + return array; + } + + /** + * Converts `string` to a property path array. + * + * @private + * @param {string} string The string to convert. + * @returns {Array} Returns the property path array. + */ + var stringToPath = memoizeCapped(function(string) { + var result = []; + if (reLeadingDot.test(string)) { + result.push(''); + } + string.replace(rePropName, function(match, number, quote, string) { + result.push(quote ? string.replace(reEscapeChar, '$1') : (number || match)); + }); + return result; + }); + + /** + * Converts `value` to a string key if it's not a string or symbol. + * + * @private + * @param {*} value The value to inspect. + * @returns {string|symbol} Returns the key. + */ + function toKey(value) { + if (typeof value == 'string' || isSymbol(value)) { + return value; + } + var result = (value + ''); + return (result == '0' && (1 / value) == -INFINITY) ? '-0' : result; + } + + /** + * Converts `func` to its source code. + * + * @private + * @param {Function} func The function to convert. + * @returns {string} Returns the source code. + */ + function toSource(func) { + if (func != null) { + try { + return funcToString.call(func); + } catch (e) {} + try { + return (func + ''); + } catch (e) {} + } + return ''; + } + + /** + * Updates wrapper `details` based on `bitmask` flags. + * + * @private + * @returns {Array} details The details to modify. + * @param {number} bitmask The bitmask flags. See `createWrap` for more details. + * @returns {Array} Returns `details`. + */ + function updateWrapDetails(details, bitmask) { + arrayEach(wrapFlags, function(pair) { + var value = '_.' + pair[0]; + if ((bitmask & pair[1]) && !arrayIncludes(details, value)) { + details.push(value); + } + }); + return details.sort(); + } + + /** + * Creates a clone of `wrapper`. + * + * @private + * @param {Object} wrapper The wrapper to clone. + * @returns {Object} Returns the cloned wrapper. + */ + function wrapperClone(wrapper) { + if (wrapper instanceof LazyWrapper) { + return wrapper.clone(); + } + var result = new LodashWrapper(wrapper.__wrapped__, wrapper.__chain__); + result.__actions__ = copyArray(wrapper.__actions__); + result.__index__ = wrapper.__index__; + result.__values__ = wrapper.__values__; + return result; + } + + /*------------------------------------------------------------------------*/ + + /** + * Creates an array of elements split into groups the length of `size`. + * If `array` can't be split evenly, the final chunk will be the remaining + * elements. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Array + * @param {Array} array The array to process. + * @param {number} [size=1] The length of each chunk + * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`. + * @returns {Array} Returns the new array of chunks. + * @example + * + * _.chunk(['a', 'b', 'c', 'd'], 2); + * // => [['a', 'b'], ['c', 'd']] + * + * _.chunk(['a', 'b', 'c', 'd'], 3); + * // => [['a', 'b', 'c'], ['d']] + */ + function chunk(array, size, guard) { + if ((guard ? isIterateeCall(array, size, guard) : size === undefined)) { + size = 1; + } else { + size = nativeMax(toInteger(size), 0); + } + var length = array == null ? 0 : array.length; + if (!length || size < 1) { + return []; + } + var index = 0, + resIndex = 0, + result = Array(nativeCeil(length / size)); + + while (index < length) { + result[resIndex++] = baseSlice(array, index, (index += size)); + } + return result; + } + + /** + * Creates an array with all falsey values removed. The values `false`, `null`, + * `0`, `""`, `undefined`, and `NaN` are falsey. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Array + * @param {Array} array The array to compact. + * @returns {Array} Returns the new array of filtered values. + * @example + * + * _.compact([0, 1, false, 2, '', 3]); + * // => [1, 2, 3] + */ + function compact(array) { + var index = -1, + length = array == null ? 0 : array.length, + resIndex = 0, + result = []; + + while (++index < length) { + var value = array[index]; + if (value) { + result[resIndex++] = value; + } + } + return result; + } + + /** + * Creates a new array concatenating `array` with any additional arrays + * and/or values. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Array + * @param {Array} array The array to concatenate. + * @param {...*} [values] The values to concatenate. + * @returns {Array} Returns the new concatenated array. + * @example + * + * var array = [1]; + * var other = _.concat(array, 2, [3], [[4]]); + * + * console.log(other); + * // => [1, 2, 3, [4]] + * + * console.log(array); + * // => [1] + */ + function concat() { + var length = arguments.length; + if (!length) { + return []; + } + var args = Array(length - 1), + array = arguments[0], + index = length; + + while (index--) { + args[index - 1] = arguments[index]; + } + return arrayPush(isArray(array) ? copyArray(array) : [array], baseFlatten(args, 1)); + } + + /** + * Creates an array of `array` values not included in the other given arrays + * using [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero) + * for equality comparisons. The order and references of result values are + * determined by the first array. + * + * **Note:** Unlike `_.pullAll`, this method returns a new array. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Array + * @param {Array} array The array to inspect. + * @param {...Array} [values] The values to exclude. + * @returns {Array} Returns the new array of filtered values. + * @see _.without, _.xor + * @example + * + * _.difference([2, 1], [2, 3]); + * // => [1] + */ + var difference = baseRest(function(array, values) { + return isArrayLikeObject(array) + ? baseDifference(array, baseFlatten(values, 1, isArrayLikeObject, true)) + : []; + }); + + /** + * This method is like `_.difference` except that it accepts `iteratee` which + * is invoked for each element of `array` and `values` to generate the criterion + * by which they're compared. The order and references of result values are + * determined by the first array. The iteratee is invoked with one argument: + * (value). + * + * **Note:** Unlike `_.pullAllBy`, this method returns a new array. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Array + * @param {Array} array The array to inspect. + * @param {...Array} [values] The values to exclude. + * @param {Function} [iteratee=_.identity] The iteratee invoked per element. + * @returns {Array} Returns the new array of filtered values. + * @example + * + * _.differenceBy([2.1, 1.2], [2.3, 3.4], Math.floor); + * // => [1.2] + * + * // The `_.property` iteratee shorthand. + * _.differenceBy([{ 'x': 2 }, { 'x': 1 }], [{ 'x': 1 }], 'x'); + * // => [{ 'x': 2 }] + */ + var differenceBy = baseRest(function(array, values) { + var iteratee = last(values); + if (isArrayLikeObject(iteratee)) { + iteratee = undefined; + } + return isArrayLikeObject(array) + ? baseDifference(array, baseFlatten(values, 1, isArrayLikeObject, true), getIteratee(iteratee, 2)) + : []; + }); + + /** + * This method is like `_.difference` except that it accepts `comparator` + * which is invoked to compare elements of `array` to `values`. The order and + * references of result values are determined by the first array. The comparator + * is invoked with two arguments: (arrVal, othVal). + * + * **Note:** Unlike `_.pullAllWith`, this method returns a new array. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Array + * @param {Array} array The array to inspect. + * @param {...Array} [values] The values to exclude. + * @param {Function} [comparator] The comparator invoked per element. + * @returns {Array} Returns the new array of filtered values. + * @example + * + * var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }]; + * + * _.differenceWith(objects, [{ 'x': 1, 'y': 2 }], _.isEqual); + * // => [{ 'x': 2, 'y': 1 }] + */ + var differenceWith = baseRest(function(array, values) { + var comparator = last(values); + if (isArrayLikeObject(comparator)) { + comparator = undefined; + } + return isArrayLikeObject(array) + ? baseDifference(array, baseFlatten(values, 1, isArrayLikeObject, true), undefined, comparator) + : []; + }); + + /** + * Creates a slice of `array` with `n` elements dropped from the beginning. + * + * @static + * @memberOf _ + * @since 0.5.0 + * @category Array + * @param {Array} array The array to query. + * @param {number} [n=1] The number of elements to drop. + * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`. + * @returns {Array} Returns the slice of `array`. + * @example + * + * _.drop([1, 2, 3]); + * // => [2, 3] + * + * _.drop([1, 2, 3], 2); + * // => [3] + * + * _.drop([1, 2, 3], 5); + * // => [] + * + * _.drop([1, 2, 3], 0); + * // => [1, 2, 3] + */ + function drop(array, n, guard) { + var length = array == null ? 0 : array.length; + if (!length) { + return []; + } + n = (guard || n === undefined) ? 1 : toInteger(n); + return baseSlice(array, n < 0 ? 0 : n, length); + } + + /** + * Creates a slice of `array` with `n` elements dropped from the end. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Array + * @param {Array} array The array to query. + * @param {number} [n=1] The number of elements to drop. + * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`. + * @returns {Array} Returns the slice of `array`. + * @example + * + * _.dropRight([1, 2, 3]); + * // => [1, 2] + * + * _.dropRight([1, 2, 3], 2); + * // => [1] + * + * _.dropRight([1, 2, 3], 5); + * // => [] + * + * _.dropRight([1, 2, 3], 0); + * // => [1, 2, 3] + */ + function dropRight(array, n, guard) { + var length = array == null ? 0 : array.length; + if (!length) { + return []; + } + n = (guard || n === undefined) ? 1 : toInteger(n); + n = length - n; + return baseSlice(array, 0, n < 0 ? 0 : n); + } + + /** + * Creates a slice of `array` excluding elements dropped from the end. + * Elements are dropped until `predicate` returns falsey. The predicate is + * invoked with three arguments: (value, index, array). + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Array + * @param {Array} array The array to query. + * @param {Function} [predicate=_.identity] The function invoked per iteration. + * @returns {Array} Returns the slice of `array`. + * @example + * + * var users = [ + * { 'user': 'barney', 'active': true }, + * { 'user': 'fred', 'active': false }, + * { 'user': 'pebbles', 'active': false } + * ]; + * + * _.dropRightWhile(users, function(o) { return !o.active; }); + * // => objects for ['barney'] + * + * // The `_.matches` iteratee shorthand. + * _.dropRightWhile(users, { 'user': 'pebbles', 'active': false }); + * // => objects for ['barney', 'fred'] + * + * // The `_.matchesProperty` iteratee shorthand. + * _.dropRightWhile(users, ['active', false]); + * // => objects for ['barney'] + * + * // The `_.property` iteratee shorthand. + * _.dropRightWhile(users, 'active'); + * // => objects for ['barney', 'fred', 'pebbles'] + */ + function dropRightWhile(array, predicate) { + return (array && array.length) + ? baseWhile(array, getIteratee(predicate, 3), true, true) + : []; + } + + /** + * Creates a slice of `array` excluding elements dropped from the beginning. + * Elements are dropped until `predicate` returns falsey. The predicate is + * invoked with three arguments: (value, index, array). + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Array + * @param {Array} array The array to query. + * @param {Function} [predicate=_.identity] The function invoked per iteration. + * @returns {Array} Returns the slice of `array`. + * @example + * + * var users = [ + * { 'user': 'barney', 'active': false }, + * { 'user': 'fred', 'active': false }, + * { 'user': 'pebbles', 'active': true } + * ]; + * + * _.dropWhile(users, function(o) { return !o.active; }); + * // => objects for ['pebbles'] + * + * // The `_.matches` iteratee shorthand. + * _.dropWhile(users, { 'user': 'barney', 'active': false }); + * // => objects for ['fred', 'pebbles'] + * + * // The `_.matchesProperty` iteratee shorthand. + * _.dropWhile(users, ['active', false]); + * // => objects for ['pebbles'] + * + * // The `_.property` iteratee shorthand. + * _.dropWhile(users, 'active'); + * // => objects for ['barney', 'fred', 'pebbles'] + */ + function dropWhile(array, predicate) { + return (array && array.length) + ? baseWhile(array, getIteratee(predicate, 3), true) + : []; + } + + /** + * Fills elements of `array` with `value` from `start` up to, but not + * including, `end`. + * + * **Note:** This method mutates `array`. + * + * @static + * @memberOf _ + * @since 3.2.0 + * @category Array + * @param {Array} array The array to fill. + * @param {*} value The value to fill `array` with. + * @param {number} [start=0] The start position. + * @param {number} [end=array.length] The end position. + * @returns {Array} Returns `array`. + * @example + * + * var array = [1, 2, 3]; + * + * _.fill(array, 'a'); + * console.log(array); + * // => ['a', 'a', 'a'] + * + * _.fill(Array(3), 2); + * // => [2, 2, 2] + * + * _.fill([4, 6, 8, 10], '*', 1, 3); + * // => [4, '*', '*', 10] + */ + function fill(array, value, start, end) { + var length = array == null ? 0 : array.length; + if (!length) { + return []; + } + if (start && typeof start != 'number' && isIterateeCall(array, value, start)) { + start = 0; + end = length; + } + return baseFill(array, value, start, end); + } + + /** + * This method is like `_.find` except that it returns the index of the first + * element `predicate` returns truthy for instead of the element itself. + * + * @static + * @memberOf _ + * @since 1.1.0 + * @category Array + * @param {Array} array The array to inspect. + * @param {Function} [predicate=_.identity] The function invoked per iteration. + * @param {number} [fromIndex=0] The index to search from. + * @returns {number} Returns the index of the found element, else `-1`. + * @example + * + * var users = [ + * { 'user': 'barney', 'active': false }, + * { 'user': 'fred', 'active': false }, + * { 'user': 'pebbles', 'active': true } + * ]; + * + * _.findIndex(users, function(o) { return o.user == 'barney'; }); + * // => 0 + * + * // The `_.matches` iteratee shorthand. + * _.findIndex(users, { 'user': 'fred', 'active': false }); + * // => 1 + * + * // The `_.matchesProperty` iteratee shorthand. + * _.findIndex(users, ['active', false]); + * // => 0 + * + * // The `_.property` iteratee shorthand. + * _.findIndex(users, 'active'); + * // => 2 + */ + function findIndex(array, predicate, fromIndex) { + var length = array == null ? 0 : array.length; + if (!length) { + return -1; + } + var index = fromIndex == null ? 0 : toInteger(fromIndex); + if (index < 0) { + index = nativeMax(length + index, 0); + } + return baseFindIndex(array, getIteratee(predicate, 3), index); + } + + /** + * This method is like `_.findIndex` except that it iterates over elements + * of `collection` from right to left. + * + * @static + * @memberOf _ + * @since 2.0.0 + * @category Array + * @param {Array} array The array to inspect. + * @param {Function} [predicate=_.identity] The function invoked per iteration. + * @param {number} [fromIndex=array.length-1] The index to search from. + * @returns {number} Returns the index of the found element, else `-1`. + * @example + * + * var users = [ + * { 'user': 'barney', 'active': true }, + * { 'user': 'fred', 'active': false }, + * { 'user': 'pebbles', 'active': false } + * ]; + * + * _.findLastIndex(users, function(o) { return o.user == 'pebbles'; }); + * // => 2 + * + * // The `_.matches` iteratee shorthand. + * _.findLastIndex(users, { 'user': 'barney', 'active': true }); + * // => 0 + * + * // The `_.matchesProperty` iteratee shorthand. + * _.findLastIndex(users, ['active', false]); + * // => 2 + * + * // The `_.property` iteratee shorthand. + * _.findLastIndex(users, 'active'); + * // => 0 + */ + function findLastIndex(array, predicate, fromIndex) { + var length = array == null ? 0 : array.length; + if (!length) { + return -1; + } + var index = length - 1; + if (fromIndex !== undefined) { + index = toInteger(fromIndex); + index = fromIndex < 0 + ? nativeMax(length + index, 0) + : nativeMin(index, length - 1); + } + return baseFindIndex(array, getIteratee(predicate, 3), index, true); + } + + /** + * Flattens `array` a single level deep. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Array + * @param {Array} array The array to flatten. + * @returns {Array} Returns the new flattened array. + * @example + * + * _.flatten([1, [2, [3, [4]], 5]]); + * // => [1, 2, [3, [4]], 5] + */ + function flatten(array) { + var length = array == null ? 0 : array.length; + return length ? baseFlatten(array, 1) : []; + } + + /** + * Recursively flattens `array`. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Array + * @param {Array} array The array to flatten. + * @returns {Array} Returns the new flattened array. + * @example + * + * _.flattenDeep([1, [2, [3, [4]], 5]]); + * // => [1, 2, 3, 4, 5] + */ + function flattenDeep(array) { + var length = array == null ? 0 : array.length; + return length ? baseFlatten(array, INFINITY) : []; + } + + /** + * Recursively flatten `array` up to `depth` times. + * + * @static + * @memberOf _ + * @since 4.4.0 + * @category Array + * @param {Array} array The array to flatten. + * @param {number} [depth=1] The maximum recursion depth. + * @returns {Array} Returns the new flattened array. + * @example + * + * var array = [1, [2, [3, [4]], 5]]; + * + * _.flattenDepth(array, 1); + * // => [1, 2, [3, [4]], 5] + * + * _.flattenDepth(array, 2); + * // => [1, 2, 3, [4], 5] + */ + function flattenDepth(array, depth) { + var length = array == null ? 0 : array.length; + if (!length) { + return []; + } + depth = depth === undefined ? 1 : toInteger(depth); + return baseFlatten(array, depth); + } + + /** + * The inverse of `_.toPairs`; this method returns an object composed + * from key-value `pairs`. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Array + * @param {Array} pairs The key-value pairs. + * @returns {Object} Returns the new object. + * @example + * + * _.fromPairs([['a', 1], ['b', 2]]); + * // => { 'a': 1, 'b': 2 } + */ + function fromPairs(pairs) { + var index = -1, + length = pairs == null ? 0 : pairs.length, + result = {}; + + while (++index < length) { + var pair = pairs[index]; + result[pair[0]] = pair[1]; + } + return result; + } + + /** + * Gets the first element of `array`. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @alias first + * @category Array + * @param {Array} array The array to query. + * @returns {*} Returns the first element of `array`. + * @example + * + * _.head([1, 2, 3]); + * // => 1 + * + * _.head([]); + * // => undefined + */ + function head(array) { + return (array && array.length) ? array[0] : undefined; + } + + /** + * Gets the index at which the first occurrence of `value` is found in `array` + * using [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero) + * for equality comparisons. If `fromIndex` is negative, it's used as the + * offset from the end of `array`. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Array + * @param {Array} array The array to inspect. + * @param {*} value The value to search for. + * @param {number} [fromIndex=0] The index to search from. + * @returns {number} Returns the index of the matched value, else `-1`. + * @example + * + * _.indexOf([1, 2, 1, 2], 2); + * // => 1 + * + * // Search from the `fromIndex`. + * _.indexOf([1, 2, 1, 2], 2, 2); + * // => 3 + */ + function indexOf(array, value, fromIndex) { + var length = array == null ? 0 : array.length; + if (!length) { + return -1; + } + var index = fromIndex == null ? 0 : toInteger(fromIndex); + if (index < 0) { + index = nativeMax(length + index, 0); + } + return baseIndexOf(array, value, index); + } + + /** + * Gets all but the last element of `array`. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Array + * @param {Array} array The array to query. + * @returns {Array} Returns the slice of `array`. + * @example + * + * _.initial([1, 2, 3]); + * // => [1, 2] + */ + function initial(array) { + var length = array == null ? 0 : array.length; + return length ? baseSlice(array, 0, -1) : []; + } + + /** + * Creates an array of unique values that are included in all given arrays + * using [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero) + * for equality comparisons. The order and references of result values are + * determined by the first array. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Array + * @param {...Array} [arrays] The arrays to inspect. + * @returns {Array} Returns the new array of intersecting values. + * @example + * + * _.intersection([2, 1], [2, 3]); + * // => [2] + */ + var intersection = baseRest(function(arrays) { + var mapped = arrayMap(arrays, castArrayLikeObject); + return (mapped.length && mapped[0] === arrays[0]) + ? baseIntersection(mapped) + : []; + }); + + /** + * This method is like `_.intersection` except that it accepts `iteratee` + * which is invoked for each element of each `arrays` to generate the criterion + * by which they're compared. The order and references of result values are + * determined by the first array. The iteratee is invoked with one argument: + * (value). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Array + * @param {...Array} [arrays] The arrays to inspect. + * @param {Function} [iteratee=_.identity] The iteratee invoked per element. + * @returns {Array} Returns the new array of intersecting values. + * @example + * + * _.intersectionBy([2.1, 1.2], [2.3, 3.4], Math.floor); + * // => [2.1] + * + * // The `_.property` iteratee shorthand. + * _.intersectionBy([{ 'x': 1 }], [{ 'x': 2 }, { 'x': 1 }], 'x'); + * // => [{ 'x': 1 }] + */ + var intersectionBy = baseRest(function(arrays) { + var iteratee = last(arrays), + mapped = arrayMap(arrays, castArrayLikeObject); + + if (iteratee === last(mapped)) { + iteratee = undefined; + } else { + mapped.pop(); + } + return (mapped.length && mapped[0] === arrays[0]) + ? baseIntersection(mapped, getIteratee(iteratee, 2)) + : []; + }); + + /** + * This method is like `_.intersection` except that it accepts `comparator` + * which is invoked to compare elements of `arrays`. The order and references + * of result values are determined by the first array. The comparator is + * invoked with two arguments: (arrVal, othVal). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Array + * @param {...Array} [arrays] The arrays to inspect. + * @param {Function} [comparator] The comparator invoked per element. + * @returns {Array} Returns the new array of intersecting values. + * @example + * + * var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }]; + * var others = [{ 'x': 1, 'y': 1 }, { 'x': 1, 'y': 2 }]; + * + * _.intersectionWith(objects, others, _.isEqual); + * // => [{ 'x': 1, 'y': 2 }] + */ + var intersectionWith = baseRest(function(arrays) { + var comparator = last(arrays), + mapped = arrayMap(arrays, castArrayLikeObject); + + comparator = typeof comparator == 'function' ? comparator : undefined; + if (comparator) { + mapped.pop(); + } + return (mapped.length && mapped[0] === arrays[0]) + ? baseIntersection(mapped, undefined, comparator) + : []; + }); + + /** + * Converts all elements in `array` into a string separated by `separator`. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Array + * @param {Array} array The array to convert. + * @param {string} [separator=','] The element separator. + * @returns {string} Returns the joined string. + * @example + * + * _.join(['a', 'b', 'c'], '~'); + * // => 'a~b~c' + */ + function join(array, separator) { + return array == null ? '' : nativeJoin.call(array, separator); + } + + /** + * Gets the last element of `array`. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Array + * @param {Array} array The array to query. + * @returns {*} Returns the last element of `array`. + * @example + * + * _.last([1, 2, 3]); + * // => 3 + */ + function last(array) { + var length = array == null ? 0 : array.length; + return length ? array[length - 1] : undefined; + } + + /** + * This method is like `_.indexOf` except that it iterates over elements of + * `array` from right to left. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Array + * @param {Array} array The array to inspect. + * @param {*} value The value to search for. + * @param {number} [fromIndex=array.length-1] The index to search from. + * @returns {number} Returns the index of the matched value, else `-1`. + * @example + * + * _.lastIndexOf([1, 2, 1, 2], 2); + * // => 3 + * + * // Search from the `fromIndex`. + * _.lastIndexOf([1, 2, 1, 2], 2, 2); + * // => 1 + */ + function lastIndexOf(array, value, fromIndex) { + var length = array == null ? 0 : array.length; + if (!length) { + return -1; + } + var index = length; + if (fromIndex !== undefined) { + index = toInteger(fromIndex); + index = index < 0 ? nativeMax(length + index, 0) : nativeMin(index, length - 1); + } + return value === value + ? strictLastIndexOf(array, value, index) + : baseFindIndex(array, baseIsNaN, index, true); + } + + /** + * Gets the element at index `n` of `array`. If `n` is negative, the nth + * element from the end is returned. + * + * @static + * @memberOf _ + * @since 4.11.0 + * @category Array + * @param {Array} array The array to query. + * @param {number} [n=0] The index of the element to return. + * @returns {*} Returns the nth element of `array`. + * @example + * + * var array = ['a', 'b', 'c', 'd']; + * + * _.nth(array, 1); + * // => 'b' + * + * _.nth(array, -2); + * // => 'c'; + */ + function nth(array, n) { + return (array && array.length) ? baseNth(array, toInteger(n)) : undefined; + } + + /** + * Removes all given values from `array` using + * [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero) + * for equality comparisons. + * + * **Note:** Unlike `_.without`, this method mutates `array`. Use `_.remove` + * to remove elements from an array by predicate. + * + * @static + * @memberOf _ + * @since 2.0.0 + * @category Array + * @param {Array} array The array to modify. + * @param {...*} [values] The values to remove. + * @returns {Array} Returns `array`. + * @example + * + * var array = ['a', 'b', 'c', 'a', 'b', 'c']; + * + * _.pull(array, 'a', 'c'); + * console.log(array); + * // => ['b', 'b'] + */ + var pull = baseRest(pullAll); + + /** + * This method is like `_.pull` except that it accepts an array of values to remove. + * + * **Note:** Unlike `_.difference`, this method mutates `array`. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Array + * @param {Array} array The array to modify. + * @param {Array} values The values to remove. + * @returns {Array} Returns `array`. + * @example + * + * var array = ['a', 'b', 'c', 'a', 'b', 'c']; + * + * _.pullAll(array, ['a', 'c']); + * console.log(array); + * // => ['b', 'b'] + */ + function pullAll(array, values) { + return (array && array.length && values && values.length) + ? basePullAll(array, values) + : array; + } + + /** + * This method is like `_.pullAll` except that it accepts `iteratee` which is + * invoked for each element of `array` and `values` to generate the criterion + * by which they're compared. The iteratee is invoked with one argument: (value). + * + * **Note:** Unlike `_.differenceBy`, this method mutates `array`. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Array + * @param {Array} array The array to modify. + * @param {Array} values The values to remove. + * @param {Function} [iteratee=_.identity] The iteratee invoked per element. + * @returns {Array} Returns `array`. + * @example + * + * var array = [{ 'x': 1 }, { 'x': 2 }, { 'x': 3 }, { 'x': 1 }]; + * + * _.pullAllBy(array, [{ 'x': 1 }, { 'x': 3 }], 'x'); + * console.log(array); + * // => [{ 'x': 2 }] + */ + function pullAllBy(array, values, iteratee) { + return (array && array.length && values && values.length) + ? basePullAll(array, values, getIteratee(iteratee, 2)) + : array; + } + + /** + * This method is like `_.pullAll` except that it accepts `comparator` which + * is invoked to compare elements of `array` to `values`. The comparator is + * invoked with two arguments: (arrVal, othVal). + * + * **Note:** Unlike `_.differenceWith`, this method mutates `array`. + * + * @static + * @memberOf _ + * @since 4.6.0 + * @category Array + * @param {Array} array The array to modify. + * @param {Array} values The values to remove. + * @param {Function} [comparator] The comparator invoked per element. + * @returns {Array} Returns `array`. + * @example + * + * var array = [{ 'x': 1, 'y': 2 }, { 'x': 3, 'y': 4 }, { 'x': 5, 'y': 6 }]; + * + * _.pullAllWith(array, [{ 'x': 3, 'y': 4 }], _.isEqual); + * console.log(array); + * // => [{ 'x': 1, 'y': 2 }, { 'x': 5, 'y': 6 }] + */ + function pullAllWith(array, values, comparator) { + return (array && array.length && values && values.length) + ? basePullAll(array, values, undefined, comparator) + : array; + } + + /** + * Removes elements from `array` corresponding to `indexes` and returns an + * array of removed elements. + * + * **Note:** Unlike `_.at`, this method mutates `array`. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Array + * @param {Array} array The array to modify. + * @param {...(number|number[])} [indexes] The indexes of elements to remove. + * @returns {Array} Returns the new array of removed elements. + * @example + * + * var array = ['a', 'b', 'c', 'd']; + * var pulled = _.pullAt(array, [1, 3]); + * + * console.log(array); + * // => ['a', 'c'] + * + * console.log(pulled); + * // => ['b', 'd'] + */ + var pullAt = flatRest(function(array, indexes) { + var length = array == null ? 0 : array.length, + result = baseAt(array, indexes); + + basePullAt(array, arrayMap(indexes, function(index) { + return isIndex(index, length) ? +index : index; + }).sort(compareAscending)); + + return result; + }); + + /** + * Removes all elements from `array` that `predicate` returns truthy for + * and returns an array of the removed elements. The predicate is invoked + * with three arguments: (value, index, array). + * + * **Note:** Unlike `_.filter`, this method mutates `array`. Use `_.pull` + * to pull elements from an array by value. + * + * @static + * @memberOf _ + * @since 2.0.0 + * @category Array + * @param {Array} array The array to modify. + * @param {Function} [predicate=_.identity] The function invoked per iteration. + * @returns {Array} Returns the new array of removed elements. + * @example + * + * var array = [1, 2, 3, 4]; + * var evens = _.remove(array, function(n) { + * return n % 2 == 0; + * }); + * + * console.log(array); + * // => [1, 3] + * + * console.log(evens); + * // => [2, 4] + */ + function remove(array, predicate) { + var result = []; + if (!(array && array.length)) { + return result; + } + var index = -1, + indexes = [], + length = array.length; + + predicate = getIteratee(predicate, 3); + while (++index < length) { + var value = array[index]; + if (predicate(value, index, array)) { + result.push(value); + indexes.push(index); + } + } + basePullAt(array, indexes); + return result; + } + + /** + * Reverses `array` so that the first element becomes the last, the second + * element becomes the second to last, and so on. + * + * **Note:** This method mutates `array` and is based on + * [`Array#reverse`](https://mdn.io/Array/reverse). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Array + * @param {Array} array The array to modify. + * @returns {Array} Returns `array`. + * @example + * + * var array = [1, 2, 3]; + * + * _.reverse(array); + * // => [3, 2, 1] + * + * console.log(array); + * // => [3, 2, 1] + */ + function reverse(array) { + return array == null ? array : nativeReverse.call(array); + } + + /** + * Creates a slice of `array` from `start` up to, but not including, `end`. + * + * **Note:** This method is used instead of + * [`Array#slice`](https://mdn.io/Array/slice) to ensure dense arrays are + * returned. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Array + * @param {Array} array The array to slice. + * @param {number} [start=0] The start position. + * @param {number} [end=array.length] The end position. + * @returns {Array} Returns the slice of `array`. + */ + function slice(array, start, end) { + var length = array == null ? 0 : array.length; + if (!length) { + return []; + } + if (end && typeof end != 'number' && isIterateeCall(array, start, end)) { + start = 0; + end = length; + } + else { + start = start == null ? 0 : toInteger(start); + end = end === undefined ? length : toInteger(end); + } + return baseSlice(array, start, end); + } + + /** + * Uses a binary search to determine the lowest index at which `value` + * should be inserted into `array` in order to maintain its sort order. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Array + * @param {Array} array The sorted array to inspect. + * @param {*} value The value to evaluate. + * @returns {number} Returns the index at which `value` should be inserted + * into `array`. + * @example + * + * _.sortedIndex([30, 50], 40); + * // => 1 + */ + function sortedIndex(array, value) { + return baseSortedIndex(array, value); + } + + /** + * This method is like `_.sortedIndex` except that it accepts `iteratee` + * which is invoked for `value` and each element of `array` to compute their + * sort ranking. The iteratee is invoked with one argument: (value). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Array + * @param {Array} array The sorted array to inspect. + * @param {*} value The value to evaluate. + * @param {Function} [iteratee=_.identity] The iteratee invoked per element. + * @returns {number} Returns the index at which `value` should be inserted + * into `array`. + * @example + * + * var objects = [{ 'x': 4 }, { 'x': 5 }]; + * + * _.sortedIndexBy(objects, { 'x': 4 }, function(o) { return o.x; }); + * // => 0 + * + * // The `_.property` iteratee shorthand. + * _.sortedIndexBy(objects, { 'x': 4 }, 'x'); + * // => 0 + */ + function sortedIndexBy(array, value, iteratee) { + return baseSortedIndexBy(array, value, getIteratee(iteratee, 2)); + } + + /** + * This method is like `_.indexOf` except that it performs a binary + * search on a sorted `array`. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Array + * @param {Array} array The array to inspect. + * @param {*} value The value to search for. + * @returns {number} Returns the index of the matched value, else `-1`. + * @example + * + * _.sortedIndexOf([4, 5, 5, 5, 6], 5); + * // => 1 + */ + function sortedIndexOf(array, value) { + var length = array == null ? 0 : array.length; + if (length) { + var index = baseSortedIndex(array, value); + if (index < length && eq(array[index], value)) { + return index; + } + } + return -1; + } + + /** + * This method is like `_.sortedIndex` except that it returns the highest + * index at which `value` should be inserted into `array` in order to + * maintain its sort order. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Array + * @param {Array} array The sorted array to inspect. + * @param {*} value The value to evaluate. + * @returns {number} Returns the index at which `value` should be inserted + * into `array`. + * @example + * + * _.sortedLastIndex([4, 5, 5, 5, 6], 5); + * // => 4 + */ + function sortedLastIndex(array, value) { + return baseSortedIndex(array, value, true); + } + + /** + * This method is like `_.sortedLastIndex` except that it accepts `iteratee` + * which is invoked for `value` and each element of `array` to compute their + * sort ranking. The iteratee is invoked with one argument: (value). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Array + * @param {Array} array The sorted array to inspect. + * @param {*} value The value to evaluate. + * @param {Function} [iteratee=_.identity] The iteratee invoked per element. + * @returns {number} Returns the index at which `value` should be inserted + * into `array`. + * @example + * + * var objects = [{ 'x': 4 }, { 'x': 5 }]; + * + * _.sortedLastIndexBy(objects, { 'x': 4 }, function(o) { return o.x; }); + * // => 1 + * + * // The `_.property` iteratee shorthand. + * _.sortedLastIndexBy(objects, { 'x': 4 }, 'x'); + * // => 1 + */ + function sortedLastIndexBy(array, value, iteratee) { + return baseSortedIndexBy(array, value, getIteratee(iteratee, 2), true); + } + + /** + * This method is like `_.lastIndexOf` except that it performs a binary + * search on a sorted `array`. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Array + * @param {Array} array The array to inspect. + * @param {*} value The value to search for. + * @returns {number} Returns the index of the matched value, else `-1`. + * @example + * + * _.sortedLastIndexOf([4, 5, 5, 5, 6], 5); + * // => 3 + */ + function sortedLastIndexOf(array, value) { + var length = array == null ? 0 : array.length; + if (length) { + var index = baseSortedIndex(array, value, true) - 1; + if (eq(array[index], value)) { + return index; + } + } + return -1; + } + + /** + * This method is like `_.uniq` except that it's designed and optimized + * for sorted arrays. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Array + * @param {Array} array The array to inspect. + * @returns {Array} Returns the new duplicate free array. + * @example + * + * _.sortedUniq([1, 1, 2]); + * // => [1, 2] + */ + function sortedUniq(array) { + return (array && array.length) + ? baseSortedUniq(array) + : []; + } + + /** + * This method is like `_.uniqBy` except that it's designed and optimized + * for sorted arrays. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Array + * @param {Array} array The array to inspect. + * @param {Function} [iteratee] The iteratee invoked per element. + * @returns {Array} Returns the new duplicate free array. + * @example + * + * _.sortedUniqBy([1.1, 1.2, 2.3, 2.4], Math.floor); + * // => [1.1, 2.3] + */ + function sortedUniqBy(array, iteratee) { + return (array && array.length) + ? baseSortedUniq(array, getIteratee(iteratee, 2)) + : []; + } + + /** + * Gets all but the first element of `array`. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Array + * @param {Array} array The array to query. + * @returns {Array} Returns the slice of `array`. + * @example + * + * _.tail([1, 2, 3]); + * // => [2, 3] + */ + function tail(array) { + var length = array == null ? 0 : array.length; + return length ? baseSlice(array, 1, length) : []; + } + + /** + * Creates a slice of `array` with `n` elements taken from the beginning. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Array + * @param {Array} array The array to query. + * @param {number} [n=1] The number of elements to take. + * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`. + * @returns {Array} Returns the slice of `array`. + * @example + * + * _.take([1, 2, 3]); + * // => [1] + * + * _.take([1, 2, 3], 2); + * // => [1, 2] + * + * _.take([1, 2, 3], 5); + * // => [1, 2, 3] + * + * _.take([1, 2, 3], 0); + * // => [] + */ + function take(array, n, guard) { + if (!(array && array.length)) { + return []; + } + n = (guard || n === undefined) ? 1 : toInteger(n); + return baseSlice(array, 0, n < 0 ? 0 : n); + } + + /** + * Creates a slice of `array` with `n` elements taken from the end. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Array + * @param {Array} array The array to query. + * @param {number} [n=1] The number of elements to take. + * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`. + * @returns {Array} Returns the slice of `array`. + * @example + * + * _.takeRight([1, 2, 3]); + * // => [3] + * + * _.takeRight([1, 2, 3], 2); + * // => [2, 3] + * + * _.takeRight([1, 2, 3], 5); + * // => [1, 2, 3] + * + * _.takeRight([1, 2, 3], 0); + * // => [] + */ + function takeRight(array, n, guard) { + var length = array == null ? 0 : array.length; + if (!length) { + return []; + } + n = (guard || n === undefined) ? 1 : toInteger(n); + n = length - n; + return baseSlice(array, n < 0 ? 0 : n, length); + } + + /** + * Creates a slice of `array` with elements taken from the end. Elements are + * taken until `predicate` returns falsey. The predicate is invoked with + * three arguments: (value, index, array). + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Array + * @param {Array} array The array to query. + * @param {Function} [predicate=_.identity] The function invoked per iteration. + * @returns {Array} Returns the slice of `array`. + * @example + * + * var users = [ + * { 'user': 'barney', 'active': true }, + * { 'user': 'fred', 'active': false }, + * { 'user': 'pebbles', 'active': false } + * ]; + * + * _.takeRightWhile(users, function(o) { return !o.active; }); + * // => objects for ['fred', 'pebbles'] + * + * // The `_.matches` iteratee shorthand. + * _.takeRightWhile(users, { 'user': 'pebbles', 'active': false }); + * // => objects for ['pebbles'] + * + * // The `_.matchesProperty` iteratee shorthand. + * _.takeRightWhile(users, ['active', false]); + * // => objects for ['fred', 'pebbles'] + * + * // The `_.property` iteratee shorthand. + * _.takeRightWhile(users, 'active'); + * // => [] + */ + function takeRightWhile(array, predicate) { + return (array && array.length) + ? baseWhile(array, getIteratee(predicate, 3), false, true) + : []; + } + + /** + * Creates a slice of `array` with elements taken from the beginning. Elements + * are taken until `predicate` returns falsey. The predicate is invoked with + * three arguments: (value, index, array). + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Array + * @param {Array} array The array to query. + * @param {Function} [predicate=_.identity] The function invoked per iteration. + * @returns {Array} Returns the slice of `array`. + * @example + * + * var users = [ + * { 'user': 'barney', 'active': false }, + * { 'user': 'fred', 'active': false }, + * { 'user': 'pebbles', 'active': true } + * ]; + * + * _.takeWhile(users, function(o) { return !o.active; }); + * // => objects for ['barney', 'fred'] + * + * // The `_.matches` iteratee shorthand. + * _.takeWhile(users, { 'user': 'barney', 'active': false }); + * // => objects for ['barney'] + * + * // The `_.matchesProperty` iteratee shorthand. + * _.takeWhile(users, ['active', false]); + * // => objects for ['barney', 'fred'] + * + * // The `_.property` iteratee shorthand. + * _.takeWhile(users, 'active'); + * // => [] + */ + function takeWhile(array, predicate) { + return (array && array.length) + ? baseWhile(array, getIteratee(predicate, 3)) + : []; + } + + /** + * Creates an array of unique values, in order, from all given arrays using + * [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero) + * for equality comparisons. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Array + * @param {...Array} [arrays] The arrays to inspect. + * @returns {Array} Returns the new array of combined values. + * @example + * + * _.union([2], [1, 2]); + * // => [2, 1] + */ + var union = baseRest(function(arrays) { + return baseUniq(baseFlatten(arrays, 1, isArrayLikeObject, true)); + }); + + /** + * This method is like `_.union` except that it accepts `iteratee` which is + * invoked for each element of each `arrays` to generate the criterion by + * which uniqueness is computed. Result values are chosen from the first + * array in which the value occurs. The iteratee is invoked with one argument: + * (value). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Array + * @param {...Array} [arrays] The arrays to inspect. + * @param {Function} [iteratee=_.identity] The iteratee invoked per element. + * @returns {Array} Returns the new array of combined values. + * @example + * + * _.unionBy([2.1], [1.2, 2.3], Math.floor); + * // => [2.1, 1.2] + * + * // The `_.property` iteratee shorthand. + * _.unionBy([{ 'x': 1 }], [{ 'x': 2 }, { 'x': 1 }], 'x'); + * // => [{ 'x': 1 }, { 'x': 2 }] + */ + var unionBy = baseRest(function(arrays) { + var iteratee = last(arrays); + if (isArrayLikeObject(iteratee)) { + iteratee = undefined; + } + return baseUniq(baseFlatten(arrays, 1, isArrayLikeObject, true), getIteratee(iteratee, 2)); + }); + + /** + * This method is like `_.union` except that it accepts `comparator` which + * is invoked to compare elements of `arrays`. Result values are chosen from + * the first array in which the value occurs. The comparator is invoked + * with two arguments: (arrVal, othVal). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Array + * @param {...Array} [arrays] The arrays to inspect. + * @param {Function} [comparator] The comparator invoked per element. + * @returns {Array} Returns the new array of combined values. + * @example + * + * var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }]; + * var others = [{ 'x': 1, 'y': 1 }, { 'x': 1, 'y': 2 }]; + * + * _.unionWith(objects, others, _.isEqual); + * // => [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }, { 'x': 1, 'y': 1 }] + */ + var unionWith = baseRest(function(arrays) { + var comparator = last(arrays); + comparator = typeof comparator == 'function' ? comparator : undefined; + return baseUniq(baseFlatten(arrays, 1, isArrayLikeObject, true), undefined, comparator); + }); + + /** + * Creates a duplicate-free version of an array, using + * [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero) + * for equality comparisons, in which only the first occurrence of each element + * is kept. The order of result values is determined by the order they occur + * in the array. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Array + * @param {Array} array The array to inspect. + * @returns {Array} Returns the new duplicate free array. + * @example + * + * _.uniq([2, 1, 2]); + * // => [2, 1] + */ + function uniq(array) { + return (array && array.length) ? baseUniq(array) : []; + } + + /** + * This method is like `_.uniq` except that it accepts `iteratee` which is + * invoked for each element in `array` to generate the criterion by which + * uniqueness is computed. The order of result values is determined by the + * order they occur in the array. The iteratee is invoked with one argument: + * (value). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Array + * @param {Array} array The array to inspect. + * @param {Function} [iteratee=_.identity] The iteratee invoked per element. + * @returns {Array} Returns the new duplicate free array. + * @example + * + * _.uniqBy([2.1, 1.2, 2.3], Math.floor); + * // => [2.1, 1.2] + * + * // The `_.property` iteratee shorthand. + * _.uniqBy([{ 'x': 1 }, { 'x': 2 }, { 'x': 1 }], 'x'); + * // => [{ 'x': 1 }, { 'x': 2 }] + */ + function uniqBy(array, iteratee) { + return (array && array.length) ? baseUniq(array, getIteratee(iteratee, 2)) : []; + } + + /** + * This method is like `_.uniq` except that it accepts `comparator` which + * is invoked to compare elements of `array`. The order of result values is + * determined by the order they occur in the array.The comparator is invoked + * with two arguments: (arrVal, othVal). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Array + * @param {Array} array The array to inspect. + * @param {Function} [comparator] The comparator invoked per element. + * @returns {Array} Returns the new duplicate free array. + * @example + * + * var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }, { 'x': 1, 'y': 2 }]; + * + * _.uniqWith(objects, _.isEqual); + * // => [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }] + */ + function uniqWith(array, comparator) { + comparator = typeof comparator == 'function' ? comparator : undefined; + return (array && array.length) ? baseUniq(array, undefined, comparator) : []; + } + + /** + * This method is like `_.zip` except that it accepts an array of grouped + * elements and creates an array regrouping the elements to their pre-zip + * configuration. + * + * @static + * @memberOf _ + * @since 1.2.0 + * @category Array + * @param {Array} array The array of grouped elements to process. + * @returns {Array} Returns the new array of regrouped elements. + * @example + * + * var zipped = _.zip(['a', 'b'], [1, 2], [true, false]); + * // => [['a', 1, true], ['b', 2, false]] + * + * _.unzip(zipped); + * // => [['a', 'b'], [1, 2], [true, false]] + */ + function unzip(array) { + if (!(array && array.length)) { + return []; + } + var length = 0; + array = arrayFilter(array, function(group) { + if (isArrayLikeObject(group)) { + length = nativeMax(group.length, length); + return true; + } + }); + return baseTimes(length, function(index) { + return arrayMap(array, baseProperty(index)); + }); + } + + /** + * This method is like `_.unzip` except that it accepts `iteratee` to specify + * how regrouped values should be combined. The iteratee is invoked with the + * elements of each group: (...group). + * + * @static + * @memberOf _ + * @since 3.8.0 + * @category Array + * @param {Array} array The array of grouped elements to process. + * @param {Function} [iteratee=_.identity] The function to combine + * regrouped values. + * @returns {Array} Returns the new array of regrouped elements. + * @example + * + * var zipped = _.zip([1, 2], [10, 20], [100, 200]); + * // => [[1, 10, 100], [2, 20, 200]] + * + * _.unzipWith(zipped, _.add); + * // => [3, 30, 300] + */ + function unzipWith(array, iteratee) { + if (!(array && array.length)) { + return []; + } + var result = unzip(array); + if (iteratee == null) { + return result; + } + return arrayMap(result, function(group) { + return apply(iteratee, undefined, group); + }); + } + + /** + * Creates an array excluding all given values using + * [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero) + * for equality comparisons. + * + * **Note:** Unlike `_.pull`, this method returns a new array. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Array + * @param {Array} array The array to inspect. + * @param {...*} [values] The values to exclude. + * @returns {Array} Returns the new array of filtered values. + * @see _.difference, _.xor + * @example + * + * _.without([2, 1, 2, 3], 1, 2); + * // => [3] + */ + var without = baseRest(function(array, values) { + return isArrayLikeObject(array) + ? baseDifference(array, values) + : []; + }); + + /** + * Creates an array of unique values that is the + * [symmetric difference](https://en.wikipedia.org/wiki/Symmetric_difference) + * of the given arrays. The order of result values is determined by the order + * they occur in the arrays. + * + * @static + * @memberOf _ + * @since 2.4.0 + * @category Array + * @param {...Array} [arrays] The arrays to inspect. + * @returns {Array} Returns the new array of filtered values. + * @see _.difference, _.without + * @example + * + * _.xor([2, 1], [2, 3]); + * // => [1, 3] + */ + var xor = baseRest(function(arrays) { + return baseXor(arrayFilter(arrays, isArrayLikeObject)); + }); + + /** + * This method is like `_.xor` except that it accepts `iteratee` which is + * invoked for each element of each `arrays` to generate the criterion by + * which by which they're compared. The order of result values is determined + * by the order they occur in the arrays. The iteratee is invoked with one + * argument: (value). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Array + * @param {...Array} [arrays] The arrays to inspect. + * @param {Function} [iteratee=_.identity] The iteratee invoked per element. + * @returns {Array} Returns the new array of filtered values. + * @example + * + * _.xorBy([2.1, 1.2], [2.3, 3.4], Math.floor); + * // => [1.2, 3.4] + * + * // The `_.property` iteratee shorthand. + * _.xorBy([{ 'x': 1 }], [{ 'x': 2 }, { 'x': 1 }], 'x'); + * // => [{ 'x': 2 }] + */ + var xorBy = baseRest(function(arrays) { + var iteratee = last(arrays); + if (isArrayLikeObject(iteratee)) { + iteratee = undefined; + } + return baseXor(arrayFilter(arrays, isArrayLikeObject), getIteratee(iteratee, 2)); + }); + + /** + * This method is like `_.xor` except that it accepts `comparator` which is + * invoked to compare elements of `arrays`. The order of result values is + * determined by the order they occur in the arrays. The comparator is invoked + * with two arguments: (arrVal, othVal). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Array + * @param {...Array} [arrays] The arrays to inspect. + * @param {Function} [comparator] The comparator invoked per element. + * @returns {Array} Returns the new array of filtered values. + * @example + * + * var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }]; + * var others = [{ 'x': 1, 'y': 1 }, { 'x': 1, 'y': 2 }]; + * + * _.xorWith(objects, others, _.isEqual); + * // => [{ 'x': 2, 'y': 1 }, { 'x': 1, 'y': 1 }] + */ + var xorWith = baseRest(function(arrays) { + var comparator = last(arrays); + comparator = typeof comparator == 'function' ? comparator : undefined; + return baseXor(arrayFilter(arrays, isArrayLikeObject), undefined, comparator); + }); + + /** + * Creates an array of grouped elements, the first of which contains the + * first elements of the given arrays, the second of which contains the + * second elements of the given arrays, and so on. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Array + * @param {...Array} [arrays] The arrays to process. + * @returns {Array} Returns the new array of grouped elements. + * @example + * + * _.zip(['a', 'b'], [1, 2], [true, false]); + * // => [['a', 1, true], ['b', 2, false]] + */ + var zip = baseRest(unzip); + + /** + * This method is like `_.fromPairs` except that it accepts two arrays, + * one of property identifiers and one of corresponding values. + * + * @static + * @memberOf _ + * @since 0.4.0 + * @category Array + * @param {Array} [props=[]] The property identifiers. + * @param {Array} [values=[]] The property values. + * @returns {Object} Returns the new object. + * @example + * + * _.zipObject(['a', 'b'], [1, 2]); + * // => { 'a': 1, 'b': 2 } + */ + function zipObject(props, values) { + return baseZipObject(props || [], values || [], assignValue); + } + + /** + * This method is like `_.zipObject` except that it supports property paths. + * + * @static + * @memberOf _ + * @since 4.1.0 + * @category Array + * @param {Array} [props=[]] The property identifiers. + * @param {Array} [values=[]] The property values. + * @returns {Object} Returns the new object. + * @example + * + * _.zipObjectDeep(['a.b[0].c', 'a.b[1].d'], [1, 2]); + * // => { 'a': { 'b': [{ 'c': 1 }, { 'd': 2 }] } } + */ + function zipObjectDeep(props, values) { + return baseZipObject(props || [], values || [], baseSet); + } + + /** + * This method is like `_.zip` except that it accepts `iteratee` to specify + * how grouped values should be combined. The iteratee is invoked with the + * elements of each group: (...group). + * + * @static + * @memberOf _ + * @since 3.8.0 + * @category Array + * @param {...Array} [arrays] The arrays to process. + * @param {Function} [iteratee=_.identity] The function to combine + * grouped values. + * @returns {Array} Returns the new array of grouped elements. + * @example + * + * _.zipWith([1, 2], [10, 20], [100, 200], function(a, b, c) { + * return a + b + c; + * }); + * // => [111, 222] + */ + var zipWith = baseRest(function(arrays) { + var length = arrays.length, + iteratee = length > 1 ? arrays[length - 1] : undefined; + + iteratee = typeof iteratee == 'function' ? (arrays.pop(), iteratee) : undefined; + return unzipWith(arrays, iteratee); + }); + + /*------------------------------------------------------------------------*/ + + /** + * Creates a `lodash` wrapper instance that wraps `value` with explicit method + * chain sequences enabled. The result of such sequences must be unwrapped + * with `_#value`. + * + * @static + * @memberOf _ + * @since 1.3.0 + * @category Seq + * @param {*} value The value to wrap. + * @returns {Object} Returns the new `lodash` wrapper instance. + * @example + * + * var users = [ + * { 'user': 'barney', 'age': 36 }, + * { 'user': 'fred', 'age': 40 }, + * { 'user': 'pebbles', 'age': 1 } + * ]; + * + * var youngest = _ + * .chain(users) + * .sortBy('age') + * .map(function(o) { + * return o.user + ' is ' + o.age; + * }) + * .head() + * .value(); + * // => 'pebbles is 1' + */ + function chain(value) { + var result = lodash(value); + result.__chain__ = true; + return result; + } + + /** + * This method invokes `interceptor` and returns `value`. The interceptor + * is invoked with one argument; (value). The purpose of this method is to + * "tap into" a method chain sequence in order to modify intermediate results. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Seq + * @param {*} value The value to provide to `interceptor`. + * @param {Function} interceptor The function to invoke. + * @returns {*} Returns `value`. + * @example + * + * _([1, 2, 3]) + * .tap(function(array) { + * // Mutate input array. + * array.pop(); + * }) + * .reverse() + * .value(); + * // => [2, 1] + */ + function tap(value, interceptor) { + interceptor(value); + return value; + } + + /** + * This method is like `_.tap` except that it returns the result of `interceptor`. + * The purpose of this method is to "pass thru" values replacing intermediate + * results in a method chain sequence. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Seq + * @param {*} value The value to provide to `interceptor`. + * @param {Function} interceptor The function to invoke. + * @returns {*} Returns the result of `interceptor`. + * @example + * + * _(' abc ') + * .chain() + * .trim() + * .thru(function(value) { + * return [value]; + * }) + * .value(); + * // => ['abc'] + */ + function thru(value, interceptor) { + return interceptor(value); + } + + /** + * This method is the wrapper version of `_.at`. + * + * @name at + * @memberOf _ + * @since 1.0.0 + * @category Seq + * @param {...(string|string[])} [paths] The property paths to pick. + * @returns {Object} Returns the new `lodash` wrapper instance. + * @example + * + * var object = { 'a': [{ 'b': { 'c': 3 } }, 4] }; + * + * _(object).at(['a[0].b.c', 'a[1]']).value(); + * // => [3, 4] + */ + var wrapperAt = flatRest(function(paths) { + var length = paths.length, + start = length ? paths[0] : 0, + value = this.__wrapped__, + interceptor = function(object) { return baseAt(object, paths); }; + + if (length > 1 || this.__actions__.length || + !(value instanceof LazyWrapper) || !isIndex(start)) { + return this.thru(interceptor); + } + value = value.slice(start, +start + (length ? 1 : 0)); + value.__actions__.push({ + 'func': thru, + 'args': [interceptor], + 'thisArg': undefined + }); + return new LodashWrapper(value, this.__chain__).thru(function(array) { + if (length && !array.length) { + array.push(undefined); + } + return array; + }); + }); + + /** + * Creates a `lodash` wrapper instance with explicit method chain sequences enabled. + * + * @name chain + * @memberOf _ + * @since 0.1.0 + * @category Seq + * @returns {Object} Returns the new `lodash` wrapper instance. + * @example + * + * var users = [ + * { 'user': 'barney', 'age': 36 }, + * { 'user': 'fred', 'age': 40 } + * ]; + * + * // A sequence without explicit chaining. + * _(users).head(); + * // => { 'user': 'barney', 'age': 36 } + * + * // A sequence with explicit chaining. + * _(users) + * .chain() + * .head() + * .pick('user') + * .value(); + * // => { 'user': 'barney' } + */ + function wrapperChain() { + return chain(this); + } + + /** + * Executes the chain sequence and returns the wrapped result. + * + * @name commit + * @memberOf _ + * @since 3.2.0 + * @category Seq + * @returns {Object} Returns the new `lodash` wrapper instance. + * @example + * + * var array = [1, 2]; + * var wrapped = _(array).push(3); + * + * console.log(array); + * // => [1, 2] + * + * wrapped = wrapped.commit(); + * console.log(array); + * // => [1, 2, 3] + * + * wrapped.last(); + * // => 3 + * + * console.log(array); + * // => [1, 2, 3] + */ + function wrapperCommit() { + return new LodashWrapper(this.value(), this.__chain__); + } + + /** + * Gets the next value on a wrapped object following the + * [iterator protocol](https://mdn.io/iteration_protocols#iterator). + * + * @name next + * @memberOf _ + * @since 4.0.0 + * @category Seq + * @returns {Object} Returns the next iterator value. + * @example + * + * var wrapped = _([1, 2]); + * + * wrapped.next(); + * // => { 'done': false, 'value': 1 } + * + * wrapped.next(); + * // => { 'done': false, 'value': 2 } + * + * wrapped.next(); + * // => { 'done': true, 'value': undefined } + */ + function wrapperNext() { + if (this.__values__ === undefined) { + this.__values__ = toArray(this.value()); + } + var done = this.__index__ >= this.__values__.length, + value = done ? undefined : this.__values__[this.__index__++]; + + return { 'done': done, 'value': value }; + } + + /** + * Enables the wrapper to be iterable. + * + * @name Symbol.iterator + * @memberOf _ + * @since 4.0.0 + * @category Seq + * @returns {Object} Returns the wrapper object. + * @example + * + * var wrapped = _([1, 2]); + * + * wrapped[Symbol.iterator]() === wrapped; + * // => true + * + * Array.from(wrapped); + * // => [1, 2] + */ + function wrapperToIterator() { + return this; + } + + /** + * Creates a clone of the chain sequence planting `value` as the wrapped value. + * + * @name plant + * @memberOf _ + * @since 3.2.0 + * @category Seq + * @param {*} value The value to plant. + * @returns {Object} Returns the new `lodash` wrapper instance. + * @example + * + * function square(n) { + * return n * n; + * } + * + * var wrapped = _([1, 2]).map(square); + * var other = wrapped.plant([3, 4]); + * + * other.value(); + * // => [9, 16] + * + * wrapped.value(); + * // => [1, 4] + */ + function wrapperPlant(value) { + var result, + parent = this; + + while (parent instanceof baseLodash) { + var clone = wrapperClone(parent); + clone.__index__ = 0; + clone.__values__ = undefined; + if (result) { + previous.__wrapped__ = clone; + } else { + result = clone; + } + var previous = clone; + parent = parent.__wrapped__; + } + previous.__wrapped__ = value; + return result; + } + + /** + * This method is the wrapper version of `_.reverse`. + * + * **Note:** This method mutates the wrapped array. + * + * @name reverse + * @memberOf _ + * @since 0.1.0 + * @category Seq + * @returns {Object} Returns the new `lodash` wrapper instance. + * @example + * + * var array = [1, 2, 3]; + * + * _(array).reverse().value() + * // => [3, 2, 1] + * + * console.log(array); + * // => [3, 2, 1] + */ + function wrapperReverse() { + var value = this.__wrapped__; + if (value instanceof LazyWrapper) { + var wrapped = value; + if (this.__actions__.length) { + wrapped = new LazyWrapper(this); + } + wrapped = wrapped.reverse(); + wrapped.__actions__.push({ + 'func': thru, + 'args': [reverse], + 'thisArg': undefined + }); + return new LodashWrapper(wrapped, this.__chain__); + } + return this.thru(reverse); + } + + /** + * Executes the chain sequence to resolve the unwrapped value. + * + * @name value + * @memberOf _ + * @since 0.1.0 + * @alias toJSON, valueOf + * @category Seq + * @returns {*} Returns the resolved unwrapped value. + * @example + * + * _([1, 2, 3]).value(); + * // => [1, 2, 3] + */ + function wrapperValue() { + return baseWrapperValue(this.__wrapped__, this.__actions__); + } + + /*------------------------------------------------------------------------*/ + + /** + * Creates an object composed of keys generated from the results of running + * each element of `collection` thru `iteratee`. The corresponding value of + * each key is the number of times the key was returned by `iteratee`. The + * iteratee is invoked with one argument: (value). + * + * @static + * @memberOf _ + * @since 0.5.0 + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [iteratee=_.identity] The iteratee to transform keys. + * @returns {Object} Returns the composed aggregate object. + * @example + * + * _.countBy([6.1, 4.2, 6.3], Math.floor); + * // => { '4': 1, '6': 2 } + * + * // The `_.property` iteratee shorthand. + * _.countBy(['one', 'two', 'three'], 'length'); + * // => { '3': 2, '5': 1 } + */ + var countBy = createAggregator(function(result, value, key) { + if (hasOwnProperty.call(result, key)) { + ++result[key]; + } else { + baseAssignValue(result, key, 1); + } + }); + + /** + * Checks if `predicate` returns truthy for **all** elements of `collection`. + * Iteration is stopped once `predicate` returns falsey. The predicate is + * invoked with three arguments: (value, index|key, collection). + * + * **Note:** This method returns `true` for + * [empty collections](https://en.wikipedia.org/wiki/Empty_set) because + * [everything is true](https://en.wikipedia.org/wiki/Vacuous_truth) of + * elements of empty collections. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [predicate=_.identity] The function invoked per iteration. + * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`. + * @returns {boolean} Returns `true` if all elements pass the predicate check, + * else `false`. + * @example + * + * _.every([true, 1, null, 'yes'], Boolean); + * // => false + * + * var users = [ + * { 'user': 'barney', 'age': 36, 'active': false }, + * { 'user': 'fred', 'age': 40, 'active': false } + * ]; + * + * // The `_.matches` iteratee shorthand. + * _.every(users, { 'user': 'barney', 'active': false }); + * // => false + * + * // The `_.matchesProperty` iteratee shorthand. + * _.every(users, ['active', false]); + * // => true + * + * // The `_.property` iteratee shorthand. + * _.every(users, 'active'); + * // => false + */ + function every(collection, predicate, guard) { + var func = isArray(collection) ? arrayEvery : baseEvery; + if (guard && isIterateeCall(collection, predicate, guard)) { + predicate = undefined; + } + return func(collection, getIteratee(predicate, 3)); + } + + /** + * Iterates over elements of `collection`, returning an array of all elements + * `predicate` returns truthy for. The predicate is invoked with three + * arguments: (value, index|key, collection). + * + * **Note:** Unlike `_.remove`, this method returns a new array. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [predicate=_.identity] The function invoked per iteration. + * @returns {Array} Returns the new filtered array. + * @see _.reject + * @example + * + * var users = [ + * { 'user': 'barney', 'age': 36, 'active': true }, + * { 'user': 'fred', 'age': 40, 'active': false } + * ]; + * + * _.filter(users, function(o) { return !o.active; }); + * // => objects for ['fred'] + * + * // The `_.matches` iteratee shorthand. + * _.filter(users, { 'age': 36, 'active': true }); + * // => objects for ['barney'] + * + * // The `_.matchesProperty` iteratee shorthand. + * _.filter(users, ['active', false]); + * // => objects for ['fred'] + * + * // The `_.property` iteratee shorthand. + * _.filter(users, 'active'); + * // => objects for ['barney'] + */ + function filter(collection, predicate) { + var func = isArray(collection) ? arrayFilter : baseFilter; + return func(collection, getIteratee(predicate, 3)); + } + + /** + * Iterates over elements of `collection`, returning the first element + * `predicate` returns truthy for. The predicate is invoked with three + * arguments: (value, index|key, collection). + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Collection + * @param {Array|Object} collection The collection to inspect. + * @param {Function} [predicate=_.identity] The function invoked per iteration. + * @param {number} [fromIndex=0] The index to search from. + * @returns {*} Returns the matched element, else `undefined`. + * @example + * + * var users = [ + * { 'user': 'barney', 'age': 36, 'active': true }, + * { 'user': 'fred', 'age': 40, 'active': false }, + * { 'user': 'pebbles', 'age': 1, 'active': true } + * ]; + * + * _.find(users, function(o) { return o.age < 40; }); + * // => object for 'barney' + * + * // The `_.matches` iteratee shorthand. + * _.find(users, { 'age': 1, 'active': true }); + * // => object for 'pebbles' + * + * // The `_.matchesProperty` iteratee shorthand. + * _.find(users, ['active', false]); + * // => object for 'fred' + * + * // The `_.property` iteratee shorthand. + * _.find(users, 'active'); + * // => object for 'barney' + */ + var find = createFind(findIndex); + + /** + * This method is like `_.find` except that it iterates over elements of + * `collection` from right to left. + * + * @static + * @memberOf _ + * @since 2.0.0 + * @category Collection + * @param {Array|Object} collection The collection to inspect. + * @param {Function} [predicate=_.identity] The function invoked per iteration. + * @param {number} [fromIndex=collection.length-1] The index to search from. + * @returns {*} Returns the matched element, else `undefined`. + * @example + * + * _.findLast([1, 2, 3, 4], function(n) { + * return n % 2 == 1; + * }); + * // => 3 + */ + var findLast = createFind(findLastIndex); + + /** + * Creates a flattened array of values by running each element in `collection` + * thru `iteratee` and flattening the mapped results. The iteratee is invoked + * with three arguments: (value, index|key, collection). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @returns {Array} Returns the new flattened array. + * @example + * + * function duplicate(n) { + * return [n, n]; + * } + * + * _.flatMap([1, 2], duplicate); + * // => [1, 1, 2, 2] + */ + function flatMap(collection, iteratee) { + return baseFlatten(map(collection, iteratee), 1); + } + + /** + * This method is like `_.flatMap` except that it recursively flattens the + * mapped results. + * + * @static + * @memberOf _ + * @since 4.7.0 + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @returns {Array} Returns the new flattened array. + * @example + * + * function duplicate(n) { + * return [[[n, n]]]; + * } + * + * _.flatMapDeep([1, 2], duplicate); + * // => [1, 1, 2, 2] + */ + function flatMapDeep(collection, iteratee) { + return baseFlatten(map(collection, iteratee), INFINITY); + } + + /** + * This method is like `_.flatMap` except that it recursively flattens the + * mapped results up to `depth` times. + * + * @static + * @memberOf _ + * @since 4.7.0 + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @param {number} [depth=1] The maximum recursion depth. + * @returns {Array} Returns the new flattened array. + * @example + * + * function duplicate(n) { + * return [[[n, n]]]; + * } + * + * _.flatMapDepth([1, 2], duplicate, 2); + * // => [[1, 1], [2, 2]] + */ + function flatMapDepth(collection, iteratee, depth) { + depth = depth === undefined ? 1 : toInteger(depth); + return baseFlatten(map(collection, iteratee), depth); + } + + /** + * Iterates over elements of `collection` and invokes `iteratee` for each element. + * The iteratee is invoked with three arguments: (value, index|key, collection). + * Iteratee functions may exit iteration early by explicitly returning `false`. + * + * **Note:** As with other "Collections" methods, objects with a "length" + * property are iterated like arrays. To avoid this behavior use `_.forIn` + * or `_.forOwn` for object iteration. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @alias each + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @returns {Array|Object} Returns `collection`. + * @see _.forEachRight + * @example + * + * _.forEach([1, 2], function(value) { + * console.log(value); + * }); + * // => Logs `1` then `2`. + * + * _.forEach({ 'a': 1, 'b': 2 }, function(value, key) { + * console.log(key); + * }); + * // => Logs 'a' then 'b' (iteration order is not guaranteed). + */ + function forEach(collection, iteratee) { + var func = isArray(collection) ? arrayEach : baseEach; + return func(collection, getIteratee(iteratee, 3)); + } + + /** + * This method is like `_.forEach` except that it iterates over elements of + * `collection` from right to left. + * + * @static + * @memberOf _ + * @since 2.0.0 + * @alias eachRight + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @returns {Array|Object} Returns `collection`. + * @see _.forEach + * @example + * + * _.forEachRight([1, 2], function(value) { + * console.log(value); + * }); + * // => Logs `2` then `1`. + */ + function forEachRight(collection, iteratee) { + var func = isArray(collection) ? arrayEachRight : baseEachRight; + return func(collection, getIteratee(iteratee, 3)); + } + + /** + * Creates an object composed of keys generated from the results of running + * each element of `collection` thru `iteratee`. The order of grouped values + * is determined by the order they occur in `collection`. The corresponding + * value of each key is an array of elements responsible for generating the + * key. The iteratee is invoked with one argument: (value). + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [iteratee=_.identity] The iteratee to transform keys. + * @returns {Object} Returns the composed aggregate object. + * @example + * + * _.groupBy([6.1, 4.2, 6.3], Math.floor); + * // => { '4': [4.2], '6': [6.1, 6.3] } + * + * // The `_.property` iteratee shorthand. + * _.groupBy(['one', 'two', 'three'], 'length'); + * // => { '3': ['one', 'two'], '5': ['three'] } + */ + var groupBy = createAggregator(function(result, value, key) { + if (hasOwnProperty.call(result, key)) { + result[key].push(value); + } else { + baseAssignValue(result, key, [value]); + } + }); + + /** + * Checks if `value` is in `collection`. If `collection` is a string, it's + * checked for a substring of `value`, otherwise + * [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero) + * is used for equality comparisons. If `fromIndex` is negative, it's used as + * the offset from the end of `collection`. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Collection + * @param {Array|Object|string} collection The collection to inspect. + * @param {*} value The value to search for. + * @param {number} [fromIndex=0] The index to search from. + * @param- {Object} [guard] Enables use as an iteratee for methods like `_.reduce`. + * @returns {boolean} Returns `true` if `value` is found, else `false`. + * @example + * + * _.includes([1, 2, 3], 1); + * // => true + * + * _.includes([1, 2, 3], 1, 2); + * // => false + * + * _.includes({ 'a': 1, 'b': 2 }, 1); + * // => true + * + * _.includes('abcd', 'bc'); + * // => true + */ + function includes(collection, value, fromIndex, guard) { + collection = isArrayLike(collection) ? collection : values(collection); + fromIndex = (fromIndex && !guard) ? toInteger(fromIndex) : 0; + + var length = collection.length; + if (fromIndex < 0) { + fromIndex = nativeMax(length + fromIndex, 0); + } + return isString(collection) + ? (fromIndex <= length && collection.indexOf(value, fromIndex) > -1) + : (!!length && baseIndexOf(collection, value, fromIndex) > -1); + } + + /** + * Invokes the method at `path` of each element in `collection`, returning + * an array of the results of each invoked method. Any additional arguments + * are provided to each invoked method. If `path` is a function, it's invoked + * for, and `this` bound to, each element in `collection`. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Array|Function|string} path The path of the method to invoke or + * the function invoked per iteration. + * @param {...*} [args] The arguments to invoke each method with. + * @returns {Array} Returns the array of results. + * @example + * + * _.invokeMap([[5, 1, 7], [3, 2, 1]], 'sort'); + * // => [[1, 5, 7], [1, 2, 3]] + * + * _.invokeMap([123, 456], String.prototype.split, ''); + * // => [['1', '2', '3'], ['4', '5', '6']] + */ + var invokeMap = baseRest(function(collection, path, args) { + var index = -1, + isFunc = typeof path == 'function', + result = isArrayLike(collection) ? Array(collection.length) : []; + + baseEach(collection, function(value) { + result[++index] = isFunc ? apply(path, value, args) : baseInvoke(value, path, args); + }); + return result; + }); + + /** + * Creates an object composed of keys generated from the results of running + * each element of `collection` thru `iteratee`. The corresponding value of + * each key is the last element responsible for generating the key. The + * iteratee is invoked with one argument: (value). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [iteratee=_.identity] The iteratee to transform keys. + * @returns {Object} Returns the composed aggregate object. + * @example + * + * var array = [ + * { 'dir': 'left', 'code': 97 }, + * { 'dir': 'right', 'code': 100 } + * ]; + * + * _.keyBy(array, function(o) { + * return String.fromCharCode(o.code); + * }); + * // => { 'a': { 'dir': 'left', 'code': 97 }, 'd': { 'dir': 'right', 'code': 100 } } + * + * _.keyBy(array, 'dir'); + * // => { 'left': { 'dir': 'left', 'code': 97 }, 'right': { 'dir': 'right', 'code': 100 } } + */ + var keyBy = createAggregator(function(result, value, key) { + baseAssignValue(result, key, value); + }); + + /** + * Creates an array of values by running each element in `collection` thru + * `iteratee`. The iteratee is invoked with three arguments: + * (value, index|key, collection). + * + * Many lodash methods are guarded to work as iteratees for methods like + * `_.every`, `_.filter`, `_.map`, `_.mapValues`, `_.reject`, and `_.some`. + * + * The guarded methods are: + * `ary`, `chunk`, `curry`, `curryRight`, `drop`, `dropRight`, `every`, + * `fill`, `invert`, `parseInt`, `random`, `range`, `rangeRight`, `repeat`, + * `sampleSize`, `slice`, `some`, `sortBy`, `split`, `take`, `takeRight`, + * `template`, `trim`, `trimEnd`, `trimStart`, and `words` + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @returns {Array} Returns the new mapped array. + * @example + * + * function square(n) { + * return n * n; + * } + * + * _.map([4, 8], square); + * // => [16, 64] + * + * _.map({ 'a': 4, 'b': 8 }, square); + * // => [16, 64] (iteration order is not guaranteed) + * + * var users = [ + * { 'user': 'barney' }, + * { 'user': 'fred' } + * ]; + * + * // The `_.property` iteratee shorthand. + * _.map(users, 'user'); + * // => ['barney', 'fred'] + */ + function map(collection, iteratee) { + var func = isArray(collection) ? arrayMap : baseMap; + return func(collection, getIteratee(iteratee, 3)); + } + + /** + * This method is like `_.sortBy` except that it allows specifying the sort + * orders of the iteratees to sort by. If `orders` is unspecified, all values + * are sorted in ascending order. Otherwise, specify an order of "desc" for + * descending or "asc" for ascending sort order of corresponding values. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Array[]|Function[]|Object[]|string[]} [iteratees=[_.identity]] + * The iteratees to sort by. + * @param {string[]} [orders] The sort orders of `iteratees`. + * @param- {Object} [guard] Enables use as an iteratee for methods like `_.reduce`. + * @returns {Array} Returns the new sorted array. + * @example + * + * var users = [ + * { 'user': 'fred', 'age': 48 }, + * { 'user': 'barney', 'age': 34 }, + * { 'user': 'fred', 'age': 40 }, + * { 'user': 'barney', 'age': 36 } + * ]; + * + * // Sort by `user` in ascending order and by `age` in descending order. + * _.orderBy(users, ['user', 'age'], ['asc', 'desc']); + * // => objects for [['barney', 36], ['barney', 34], ['fred', 48], ['fred', 40]] + */ + function orderBy(collection, iteratees, orders, guard) { + if (collection == null) { + return []; + } + if (!isArray(iteratees)) { + iteratees = iteratees == null ? [] : [iteratees]; + } + orders = guard ? undefined : orders; + if (!isArray(orders)) { + orders = orders == null ? [] : [orders]; + } + return baseOrderBy(collection, iteratees, orders); + } + + /** + * Creates an array of elements split into two groups, the first of which + * contains elements `predicate` returns truthy for, the second of which + * contains elements `predicate` returns falsey for. The predicate is + * invoked with one argument: (value). + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [predicate=_.identity] The function invoked per iteration. + * @returns {Array} Returns the array of grouped elements. + * @example + * + * var users = [ + * { 'user': 'barney', 'age': 36, 'active': false }, + * { 'user': 'fred', 'age': 40, 'active': true }, + * { 'user': 'pebbles', 'age': 1, 'active': false } + * ]; + * + * _.partition(users, function(o) { return o.active; }); + * // => objects for [['fred'], ['barney', 'pebbles']] + * + * // The `_.matches` iteratee shorthand. + * _.partition(users, { 'age': 1, 'active': false }); + * // => objects for [['pebbles'], ['barney', 'fred']] + * + * // The `_.matchesProperty` iteratee shorthand. + * _.partition(users, ['active', false]); + * // => objects for [['barney', 'pebbles'], ['fred']] + * + * // The `_.property` iteratee shorthand. + * _.partition(users, 'active'); + * // => objects for [['fred'], ['barney', 'pebbles']] + */ + var partition = createAggregator(function(result, value, key) { + result[key ? 0 : 1].push(value); + }, function() { return [[], []]; }); + + /** + * Reduces `collection` to a value which is the accumulated result of running + * each element in `collection` thru `iteratee`, where each successive + * invocation is supplied the return value of the previous. If `accumulator` + * is not given, the first element of `collection` is used as the initial + * value. The iteratee is invoked with four arguments: + * (accumulator, value, index|key, collection). + * + * Many lodash methods are guarded to work as iteratees for methods like + * `_.reduce`, `_.reduceRight`, and `_.transform`. + * + * The guarded methods are: + * `assign`, `defaults`, `defaultsDeep`, `includes`, `merge`, `orderBy`, + * and `sortBy` + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @param {*} [accumulator] The initial value. + * @returns {*} Returns the accumulated value. + * @see _.reduceRight + * @example + * + * _.reduce([1, 2], function(sum, n) { + * return sum + n; + * }, 0); + * // => 3 + * + * _.reduce({ 'a': 1, 'b': 2, 'c': 1 }, function(result, value, key) { + * (result[value] || (result[value] = [])).push(key); + * return result; + * }, {}); + * // => { '1': ['a', 'c'], '2': ['b'] } (iteration order is not guaranteed) + */ + function reduce(collection, iteratee, accumulator) { + var func = isArray(collection) ? arrayReduce : baseReduce, + initAccum = arguments.length < 3; + + return func(collection, getIteratee(iteratee, 4), accumulator, initAccum, baseEach); + } + + /** + * This method is like `_.reduce` except that it iterates over elements of + * `collection` from right to left. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @param {*} [accumulator] The initial value. + * @returns {*} Returns the accumulated value. + * @see _.reduce + * @example + * + * var array = [[0, 1], [2, 3], [4, 5]]; + * + * _.reduceRight(array, function(flattened, other) { + * return flattened.concat(other); + * }, []); + * // => [4, 5, 2, 3, 0, 1] + */ + function reduceRight(collection, iteratee, accumulator) { + var func = isArray(collection) ? arrayReduceRight : baseReduce, + initAccum = arguments.length < 3; + + return func(collection, getIteratee(iteratee, 4), accumulator, initAccum, baseEachRight); + } + + /** + * The opposite of `_.filter`; this method returns the elements of `collection` + * that `predicate` does **not** return truthy for. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [predicate=_.identity] The function invoked per iteration. + * @returns {Array} Returns the new filtered array. + * @see _.filter + * @example + * + * var users = [ + * { 'user': 'barney', 'age': 36, 'active': false }, + * { 'user': 'fred', 'age': 40, 'active': true } + * ]; + * + * _.reject(users, function(o) { return !o.active; }); + * // => objects for ['fred'] + * + * // The `_.matches` iteratee shorthand. + * _.reject(users, { 'age': 40, 'active': true }); + * // => objects for ['barney'] + * + * // The `_.matchesProperty` iteratee shorthand. + * _.reject(users, ['active', false]); + * // => objects for ['fred'] + * + * // The `_.property` iteratee shorthand. + * _.reject(users, 'active'); + * // => objects for ['barney'] + */ + function reject(collection, predicate) { + var func = isArray(collection) ? arrayFilter : baseFilter; + return func(collection, negate(getIteratee(predicate, 3))); + } + + /** + * Gets a random element from `collection`. + * + * @static + * @memberOf _ + * @since 2.0.0 + * @category Collection + * @param {Array|Object} collection The collection to sample. + * @returns {*} Returns the random element. + * @example + * + * _.sample([1, 2, 3, 4]); + * // => 2 + */ + function sample(collection) { + var func = isArray(collection) ? arraySample : baseSample; + return func(collection); + } + + /** + * Gets `n` random elements at unique keys from `collection` up to the + * size of `collection`. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Collection + * @param {Array|Object} collection The collection to sample. + * @param {number} [n=1] The number of elements to sample. + * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`. + * @returns {Array} Returns the random elements. + * @example + * + * _.sampleSize([1, 2, 3], 2); + * // => [3, 1] + * + * _.sampleSize([1, 2, 3], 4); + * // => [2, 3, 1] + */ + function sampleSize(collection, n, guard) { + if ((guard ? isIterateeCall(collection, n, guard) : n === undefined)) { + n = 1; + } else { + n = toInteger(n); + } + var func = isArray(collection) ? arraySampleSize : baseSampleSize; + return func(collection, n); + } + + /** + * Creates an array of shuffled values, using a version of the + * [Fisher-Yates shuffle](https://en.wikipedia.org/wiki/Fisher-Yates_shuffle). + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Collection + * @param {Array|Object} collection The collection to shuffle. + * @returns {Array} Returns the new shuffled array. + * @example + * + * _.shuffle([1, 2, 3, 4]); + * // => [4, 1, 3, 2] + */ + function shuffle(collection) { + var func = isArray(collection) ? arrayShuffle : baseShuffle; + return func(collection); + } + + /** + * Gets the size of `collection` by returning its length for array-like + * values or the number of own enumerable string keyed properties for objects. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Collection + * @param {Array|Object|string} collection The collection to inspect. + * @returns {number} Returns the collection size. + * @example + * + * _.size([1, 2, 3]); + * // => 3 + * + * _.size({ 'a': 1, 'b': 2 }); + * // => 2 + * + * _.size('pebbles'); + * // => 7 + */ + function size(collection) { + if (collection == null) { + return 0; + } + if (isArrayLike(collection)) { + return isString(collection) ? stringSize(collection) : collection.length; + } + var tag = getTag(collection); + if (tag == mapTag || tag == setTag) { + return collection.size; + } + return baseKeys(collection).length; + } + + /** + * Checks if `predicate` returns truthy for **any** element of `collection`. + * Iteration is stopped once `predicate` returns truthy. The predicate is + * invoked with three arguments: (value, index|key, collection). + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [predicate=_.identity] The function invoked per iteration. + * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`. + * @returns {boolean} Returns `true` if any element passes the predicate check, + * else `false`. + * @example + * + * _.some([null, 0, 'yes', false], Boolean); + * // => true + * + * var users = [ + * { 'user': 'barney', 'active': true }, + * { 'user': 'fred', 'active': false } + * ]; + * + * // The `_.matches` iteratee shorthand. + * _.some(users, { 'user': 'barney', 'active': false }); + * // => false + * + * // The `_.matchesProperty` iteratee shorthand. + * _.some(users, ['active', false]); + * // => true + * + * // The `_.property` iteratee shorthand. + * _.some(users, 'active'); + * // => true + */ + function some(collection, predicate, guard) { + var func = isArray(collection) ? arraySome : baseSome; + if (guard && isIterateeCall(collection, predicate, guard)) { + predicate = undefined; + } + return func(collection, getIteratee(predicate, 3)); + } + + /** + * Creates an array of elements, sorted in ascending order by the results of + * running each element in a collection thru each iteratee. This method + * performs a stable sort, that is, it preserves the original sort order of + * equal elements. The iteratees are invoked with one argument: (value). + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {...(Function|Function[])} [iteratees=[_.identity]] + * The iteratees to sort by. + * @returns {Array} Returns the new sorted array. + * @example + * + * var users = [ + * { 'user': 'fred', 'age': 48 }, + * { 'user': 'barney', 'age': 36 }, + * { 'user': 'fred', 'age': 40 }, + * { 'user': 'barney', 'age': 34 } + * ]; + * + * _.sortBy(users, [function(o) { return o.user; }]); + * // => objects for [['barney', 36], ['barney', 34], ['fred', 48], ['fred', 40]] + * + * _.sortBy(users, ['user', 'age']); + * // => objects for [['barney', 34], ['barney', 36], ['fred', 40], ['fred', 48]] + */ + var sortBy = baseRest(function(collection, iteratees) { + if (collection == null) { + return []; + } + var length = iteratees.length; + if (length > 1 && isIterateeCall(collection, iteratees[0], iteratees[1])) { + iteratees = []; + } else if (length > 2 && isIterateeCall(iteratees[0], iteratees[1], iteratees[2])) { + iteratees = [iteratees[0]]; + } + return baseOrderBy(collection, baseFlatten(iteratees, 1), []); + }); + + /*------------------------------------------------------------------------*/ + + /** + * Gets the timestamp of the number of milliseconds that have elapsed since + * the Unix epoch (1 January 1970 00:00:00 UTC). + * + * @static + * @memberOf _ + * @since 2.4.0 + * @category Date + * @returns {number} Returns the timestamp. + * @example + * + * _.defer(function(stamp) { + * console.log(_.now() - stamp); + * }, _.now()); + * // => Logs the number of milliseconds it took for the deferred invocation. + */ + var now = ctxNow || function() { + return root.Date.now(); + }; + + /*------------------------------------------------------------------------*/ + + /** + * The opposite of `_.before`; this method creates a function that invokes + * `func` once it's called `n` or more times. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Function + * @param {number} n The number of calls before `func` is invoked. + * @param {Function} func The function to restrict. + * @returns {Function} Returns the new restricted function. + * @example + * + * var saves = ['profile', 'settings']; + * + * var done = _.after(saves.length, function() { + * console.log('done saving!'); + * }); + * + * _.forEach(saves, function(type) { + * asyncSave({ 'type': type, 'complete': done }); + * }); + * // => Logs 'done saving!' after the two async saves have completed. + */ + function after(n, func) { + if (typeof func != 'function') { + throw new TypeError(FUNC_ERROR_TEXT); + } + n = toInteger(n); + return function() { + if (--n < 1) { + return func.apply(this, arguments); + } + }; + } + + /** + * Creates a function that invokes `func`, with up to `n` arguments, + * ignoring any additional arguments. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Function + * @param {Function} func The function to cap arguments for. + * @param {number} [n=func.length] The arity cap. + * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`. + * @returns {Function} Returns the new capped function. + * @example + * + * _.map(['6', '8', '10'], _.ary(parseInt, 1)); + * // => [6, 8, 10] + */ + function ary(func, n, guard) { + n = guard ? undefined : n; + n = (func && n == null) ? func.length : n; + return createWrap(func, WRAP_ARY_FLAG, undefined, undefined, undefined, undefined, n); + } + + /** + * Creates a function that invokes `func`, with the `this` binding and arguments + * of the created function, while it's called less than `n` times. Subsequent + * calls to the created function return the result of the last `func` invocation. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Function + * @param {number} n The number of calls at which `func` is no longer invoked. + * @param {Function} func The function to restrict. + * @returns {Function} Returns the new restricted function. + * @example + * + * jQuery(element).on('click', _.before(5, addContactToList)); + * // => Allows adding up to 4 contacts to the list. + */ + function before(n, func) { + var result; + if (typeof func != 'function') { + throw new TypeError(FUNC_ERROR_TEXT); + } + n = toInteger(n); + return function() { + if (--n > 0) { + result = func.apply(this, arguments); + } + if (n <= 1) { + func = undefined; + } + return result; + }; + } + + /** + * Creates a function that invokes `func` with the `this` binding of `thisArg` + * and `partials` prepended to the arguments it receives. + * + * The `_.bind.placeholder` value, which defaults to `_` in monolithic builds, + * may be used as a placeholder for partially applied arguments. + * + * **Note:** Unlike native `Function#bind`, this method doesn't set the "length" + * property of bound functions. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Function + * @param {Function} func The function to bind. + * @param {*} thisArg The `this` binding of `func`. + * @param {...*} [partials] The arguments to be partially applied. + * @returns {Function} Returns the new bound function. + * @example + * + * function greet(greeting, punctuation) { + * return greeting + ' ' + this.user + punctuation; + * } + * + * var object = { 'user': 'fred' }; + * + * var bound = _.bind(greet, object, 'hi'); + * bound('!'); + * // => 'hi fred!' + * + * // Bound with placeholders. + * var bound = _.bind(greet, object, _, '!'); + * bound('hi'); + * // => 'hi fred!' + */ + var bind = baseRest(function(func, thisArg, partials) { + var bitmask = WRAP_BIND_FLAG; + if (partials.length) { + var holders = replaceHolders(partials, getHolder(bind)); + bitmask |= WRAP_PARTIAL_FLAG; + } + return createWrap(func, bitmask, thisArg, partials, holders); + }); + + /** + * Creates a function that invokes the method at `object[key]` with `partials` + * prepended to the arguments it receives. + * + * This method differs from `_.bind` by allowing bound functions to reference + * methods that may be redefined or don't yet exist. See + * [Peter Michaux's article](http://peter.michaux.ca/articles/lazy-function-definition-pattern) + * for more details. + * + * The `_.bindKey.placeholder` value, which defaults to `_` in monolithic + * builds, may be used as a placeholder for partially applied arguments. + * + * @static + * @memberOf _ + * @since 0.10.0 + * @category Function + * @param {Object} object The object to invoke the method on. + * @param {string} key The key of the method. + * @param {...*} [partials] The arguments to be partially applied. + * @returns {Function} Returns the new bound function. + * @example + * + * var object = { + * 'user': 'fred', + * 'greet': function(greeting, punctuation) { + * return greeting + ' ' + this.user + punctuation; + * } + * }; + * + * var bound = _.bindKey(object, 'greet', 'hi'); + * bound('!'); + * // => 'hi fred!' + * + * object.greet = function(greeting, punctuation) { + * return greeting + 'ya ' + this.user + punctuation; + * }; + * + * bound('!'); + * // => 'hiya fred!' + * + * // Bound with placeholders. + * var bound = _.bindKey(object, 'greet', _, '!'); + * bound('hi'); + * // => 'hiya fred!' + */ + var bindKey = baseRest(function(object, key, partials) { + var bitmask = WRAP_BIND_FLAG | WRAP_BIND_KEY_FLAG; + if (partials.length) { + var holders = replaceHolders(partials, getHolder(bindKey)); + bitmask |= WRAP_PARTIAL_FLAG; + } + return createWrap(key, bitmask, object, partials, holders); + }); + + /** + * Creates a function that accepts arguments of `func` and either invokes + * `func` returning its result, if at least `arity` number of arguments have + * been provided, or returns a function that accepts the remaining `func` + * arguments, and so on. The arity of `func` may be specified if `func.length` + * is not sufficient. + * + * The `_.curry.placeholder` value, which defaults to `_` in monolithic builds, + * may be used as a placeholder for provided arguments. + * + * **Note:** This method doesn't set the "length" property of curried functions. + * + * @static + * @memberOf _ + * @since 2.0.0 + * @category Function + * @param {Function} func The function to curry. + * @param {number} [arity=func.length] The arity of `func`. + * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`. + * @returns {Function} Returns the new curried function. + * @example + * + * var abc = function(a, b, c) { + * return [a, b, c]; + * }; + * + * var curried = _.curry(abc); + * + * curried(1)(2)(3); + * // => [1, 2, 3] + * + * curried(1, 2)(3); + * // => [1, 2, 3] + * + * curried(1, 2, 3); + * // => [1, 2, 3] + * + * // Curried with placeholders. + * curried(1)(_, 3)(2); + * // => [1, 2, 3] + */ + function curry(func, arity, guard) { + arity = guard ? undefined : arity; + var result = createWrap(func, WRAP_CURRY_FLAG, undefined, undefined, undefined, undefined, undefined, arity); + result.placeholder = curry.placeholder; + return result; + } + + /** + * This method is like `_.curry` except that arguments are applied to `func` + * in the manner of `_.partialRight` instead of `_.partial`. + * + * The `_.curryRight.placeholder` value, which defaults to `_` in monolithic + * builds, may be used as a placeholder for provided arguments. + * + * **Note:** This method doesn't set the "length" property of curried functions. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Function + * @param {Function} func The function to curry. + * @param {number} [arity=func.length] The arity of `func`. + * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`. + * @returns {Function} Returns the new curried function. + * @example + * + * var abc = function(a, b, c) { + * return [a, b, c]; + * }; + * + * var curried = _.curryRight(abc); + * + * curried(3)(2)(1); + * // => [1, 2, 3] + * + * curried(2, 3)(1); + * // => [1, 2, 3] + * + * curried(1, 2, 3); + * // => [1, 2, 3] + * + * // Curried with placeholders. + * curried(3)(1, _)(2); + * // => [1, 2, 3] + */ + function curryRight(func, arity, guard) { + arity = guard ? undefined : arity; + var result = createWrap(func, WRAP_CURRY_RIGHT_FLAG, undefined, undefined, undefined, undefined, undefined, arity); + result.placeholder = curryRight.placeholder; + return result; + } + + /** + * Creates a debounced function that delays invoking `func` until after `wait` + * milliseconds have elapsed since the last time the debounced function was + * invoked. The debounced function comes with a `cancel` method to cancel + * delayed `func` invocations and a `flush` method to immediately invoke them. + * Provide `options` to indicate whether `func` should be invoked on the + * leading and/or trailing edge of the `wait` timeout. The `func` is invoked + * with the last arguments provided to the debounced function. Subsequent + * calls to the debounced function return the result of the last `func` + * invocation. + * + * **Note:** If `leading` and `trailing` options are `true`, `func` is + * invoked on the trailing edge of the timeout only if the debounced function + * is invoked more than once during the `wait` timeout. + * + * If `wait` is `0` and `leading` is `false`, `func` invocation is deferred + * until to the next tick, similar to `setTimeout` with a timeout of `0`. + * + * See [David Corbacho's article](https://css-tricks.com/debouncing-throttling-explained-examples/) + * for details over the differences between `_.debounce` and `_.throttle`. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Function + * @param {Function} func The function to debounce. + * @param {number} [wait=0] The number of milliseconds to delay. + * @param {Object} [options={}] The options object. + * @param {boolean} [options.leading=false] + * Specify invoking on the leading edge of the timeout. + * @param {number} [options.maxWait] + * The maximum time `func` is allowed to be delayed before it's invoked. + * @param {boolean} [options.trailing=true] + * Specify invoking on the trailing edge of the timeout. + * @returns {Function} Returns the new debounced function. + * @example + * + * // Avoid costly calculations while the window size is in flux. + * jQuery(window).on('resize', _.debounce(calculateLayout, 150)); + * + * // Invoke `sendMail` when clicked, debouncing subsequent calls. + * jQuery(element).on('click', _.debounce(sendMail, 300, { + * 'leading': true, + * 'trailing': false + * })); + * + * // Ensure `batchLog` is invoked once after 1 second of debounced calls. + * var debounced = _.debounce(batchLog, 250, { 'maxWait': 1000 }); + * var source = new EventSource('/stream'); + * jQuery(source).on('message', debounced); + * + * // Cancel the trailing debounced invocation. + * jQuery(window).on('popstate', debounced.cancel); + */ + function debounce(func, wait, options) { + var lastArgs, + lastThis, + maxWait, + result, + timerId, + lastCallTime, + lastInvokeTime = 0, + leading = false, + maxing = false, + trailing = true; + + if (typeof func != 'function') { + throw new TypeError(FUNC_ERROR_TEXT); + } + wait = toNumber(wait) || 0; + if (isObject(options)) { + leading = !!options.leading; + maxing = 'maxWait' in options; + maxWait = maxing ? nativeMax(toNumber(options.maxWait) || 0, wait) : maxWait; + trailing = 'trailing' in options ? !!options.trailing : trailing; + } + + function invokeFunc(time) { + var args = lastArgs, + thisArg = lastThis; + + lastArgs = lastThis = undefined; + lastInvokeTime = time; + result = func.apply(thisArg, args); + return result; + } + + function leadingEdge(time) { + // Reset any `maxWait` timer. + lastInvokeTime = time; + // Start the timer for the trailing edge. + timerId = setTimeout(timerExpired, wait); + // Invoke the leading edge. + return leading ? invokeFunc(time) : result; + } + + function remainingWait(time) { + var timeSinceLastCall = time - lastCallTime, + timeSinceLastInvoke = time - lastInvokeTime, + result = wait - timeSinceLastCall; + + return maxing ? nativeMin(result, maxWait - timeSinceLastInvoke) : result; + } + + function shouldInvoke(time) { + var timeSinceLastCall = time - lastCallTime, + timeSinceLastInvoke = time - lastInvokeTime; + + // Either this is the first call, activity has stopped and we're at the + // trailing edge, the system time has gone backwards and we're treating + // it as the trailing edge, or we've hit the `maxWait` limit. + return (lastCallTime === undefined || (timeSinceLastCall >= wait) || + (timeSinceLastCall < 0) || (maxing && timeSinceLastInvoke >= maxWait)); + } + + function timerExpired() { + var time = now(); + if (shouldInvoke(time)) { + return trailingEdge(time); + } + // Restart the timer. + timerId = setTimeout(timerExpired, remainingWait(time)); + } + + function trailingEdge(time) { + timerId = undefined; + + // Only invoke if we have `lastArgs` which means `func` has been + // debounced at least once. + if (trailing && lastArgs) { + return invokeFunc(time); + } + lastArgs = lastThis = undefined; + return result; + } + + function cancel() { + if (timerId !== undefined) { + clearTimeout(timerId); + } + lastInvokeTime = 0; + lastArgs = lastCallTime = lastThis = timerId = undefined; + } + + function flush() { + return timerId === undefined ? result : trailingEdge(now()); + } + + function debounced() { + var time = now(), + isInvoking = shouldInvoke(time); + + lastArgs = arguments; + lastThis = this; + lastCallTime = time; + + if (isInvoking) { + if (timerId === undefined) { + return leadingEdge(lastCallTime); + } + if (maxing) { + // Handle invocations in a tight loop. + timerId = setTimeout(timerExpired, wait); + return invokeFunc(lastCallTime); + } + } + if (timerId === undefined) { + timerId = setTimeout(timerExpired, wait); + } + return result; + } + debounced.cancel = cancel; + debounced.flush = flush; + return debounced; + } + + /** + * Defers invoking the `func` until the current call stack has cleared. Any + * additional arguments are provided to `func` when it's invoked. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Function + * @param {Function} func The function to defer. + * @param {...*} [args] The arguments to invoke `func` with. + * @returns {number} Returns the timer id. + * @example + * + * _.defer(function(text) { + * console.log(text); + * }, 'deferred'); + * // => Logs 'deferred' after one millisecond. + */ + var defer = baseRest(function(func, args) { + return baseDelay(func, 1, args); + }); + + /** + * Invokes `func` after `wait` milliseconds. Any additional arguments are + * provided to `func` when it's invoked. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Function + * @param {Function} func The function to delay. + * @param {number} wait The number of milliseconds to delay invocation. + * @param {...*} [args] The arguments to invoke `func` with. + * @returns {number} Returns the timer id. + * @example + * + * _.delay(function(text) { + * console.log(text); + * }, 1000, 'later'); + * // => Logs 'later' after one second. + */ + var delay = baseRest(function(func, wait, args) { + return baseDelay(func, toNumber(wait) || 0, args); + }); + + /** + * Creates a function that invokes `func` with arguments reversed. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Function + * @param {Function} func The function to flip arguments for. + * @returns {Function} Returns the new flipped function. + * @example + * + * var flipped = _.flip(function() { + * return _.toArray(arguments); + * }); + * + * flipped('a', 'b', 'c', 'd'); + * // => ['d', 'c', 'b', 'a'] + */ + function flip(func) { + return createWrap(func, WRAP_FLIP_FLAG); + } + + /** + * Creates a function that memoizes the result of `func`. If `resolver` is + * provided, it determines the cache key for storing the result based on the + * arguments provided to the memoized function. By default, the first argument + * provided to the memoized function is used as the map cache key. The `func` + * is invoked with the `this` binding of the memoized function. + * + * **Note:** The cache is exposed as the `cache` property on the memoized + * function. Its creation may be customized by replacing the `_.memoize.Cache` + * constructor with one whose instances implement the + * [`Map`](http://ecma-international.org/ecma-262/7.0/#sec-properties-of-the-map-prototype-object) + * method interface of `clear`, `delete`, `get`, `has`, and `set`. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Function + * @param {Function} func The function to have its output memoized. + * @param {Function} [resolver] The function to resolve the cache key. + * @returns {Function} Returns the new memoized function. + * @example + * + * var object = { 'a': 1, 'b': 2 }; + * var other = { 'c': 3, 'd': 4 }; + * + * var values = _.memoize(_.values); + * values(object); + * // => [1, 2] + * + * values(other); + * // => [3, 4] + * + * object.a = 2; + * values(object); + * // => [1, 2] + * + * // Modify the result cache. + * values.cache.set(object, ['a', 'b']); + * values(object); + * // => ['a', 'b'] + * + * // Replace `_.memoize.Cache`. + * _.memoize.Cache = WeakMap; + */ + function memoize(func, resolver) { + if (typeof func != 'function' || (resolver != null && typeof resolver != 'function')) { + throw new TypeError(FUNC_ERROR_TEXT); + } + var memoized = function() { + var args = arguments, + key = resolver ? resolver.apply(this, args) : args[0], + cache = memoized.cache; + + if (cache.has(key)) { + return cache.get(key); + } + var result = func.apply(this, args); + memoized.cache = cache.set(key, result) || cache; + return result; + }; + memoized.cache = new (memoize.Cache || MapCache); + return memoized; + } + + // Expose `MapCache`. + memoize.Cache = MapCache; + + /** + * Creates a function that negates the result of the predicate `func`. The + * `func` predicate is invoked with the `this` binding and arguments of the + * created function. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Function + * @param {Function} predicate The predicate to negate. + * @returns {Function} Returns the new negated function. + * @example + * + * function isEven(n) { + * return n % 2 == 0; + * } + * + * _.filter([1, 2, 3, 4, 5, 6], _.negate(isEven)); + * // => [1, 3, 5] + */ + function negate(predicate) { + if (typeof predicate != 'function') { + throw new TypeError(FUNC_ERROR_TEXT); + } + return function() { + var args = arguments; + switch (args.length) { + case 0: return !predicate.call(this); + case 1: return !predicate.call(this, args[0]); + case 2: return !predicate.call(this, args[0], args[1]); + case 3: return !predicate.call(this, args[0], args[1], args[2]); + } + return !predicate.apply(this, args); + }; + } + + /** + * Creates a function that is restricted to invoking `func` once. Repeat calls + * to the function return the value of the first invocation. The `func` is + * invoked with the `this` binding and arguments of the created function. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Function + * @param {Function} func The function to restrict. + * @returns {Function} Returns the new restricted function. + * @example + * + * var initialize = _.once(createApplication); + * initialize(); + * initialize(); + * // => `createApplication` is invoked once + */ + function once(func) { + return before(2, func); + } + + /** + * Creates a function that invokes `func` with its arguments transformed. + * + * @static + * @since 4.0.0 + * @memberOf _ + * @category Function + * @param {Function} func The function to wrap. + * @param {...(Function|Function[])} [transforms=[_.identity]] + * The argument transforms. + * @returns {Function} Returns the new function. + * @example + * + * function doubled(n) { + * return n * 2; + * } + * + * function square(n) { + * return n * n; + * } + * + * var func = _.overArgs(function(x, y) { + * return [x, y]; + * }, [square, doubled]); + * + * func(9, 3); + * // => [81, 6] + * + * func(10, 5); + * // => [100, 10] + */ + var overArgs = castRest(function(func, transforms) { + transforms = (transforms.length == 1 && isArray(transforms[0])) + ? arrayMap(transforms[0], baseUnary(getIteratee())) + : arrayMap(baseFlatten(transforms, 1), baseUnary(getIteratee())); + + var funcsLength = transforms.length; + return baseRest(function(args) { + var index = -1, + length = nativeMin(args.length, funcsLength); + + while (++index < length) { + args[index] = transforms[index].call(this, args[index]); + } + return apply(func, this, args); + }); + }); + + /** + * Creates a function that invokes `func` with `partials` prepended to the + * arguments it receives. This method is like `_.bind` except it does **not** + * alter the `this` binding. + * + * The `_.partial.placeholder` value, which defaults to `_` in monolithic + * builds, may be used as a placeholder for partially applied arguments. + * + * **Note:** This method doesn't set the "length" property of partially + * applied functions. + * + * @static + * @memberOf _ + * @since 0.2.0 + * @category Function + * @param {Function} func The function to partially apply arguments to. + * @param {...*} [partials] The arguments to be partially applied. + * @returns {Function} Returns the new partially applied function. + * @example + * + * function greet(greeting, name) { + * return greeting + ' ' + name; + * } + * + * var sayHelloTo = _.partial(greet, 'hello'); + * sayHelloTo('fred'); + * // => 'hello fred' + * + * // Partially applied with placeholders. + * var greetFred = _.partial(greet, _, 'fred'); + * greetFred('hi'); + * // => 'hi fred' + */ + var partial = baseRest(function(func, partials) { + var holders = replaceHolders(partials, getHolder(partial)); + return createWrap(func, WRAP_PARTIAL_FLAG, undefined, partials, holders); + }); + + /** + * This method is like `_.partial` except that partially applied arguments + * are appended to the arguments it receives. + * + * The `_.partialRight.placeholder` value, which defaults to `_` in monolithic + * builds, may be used as a placeholder for partially applied arguments. + * + * **Note:** This method doesn't set the "length" property of partially + * applied functions. + * + * @static + * @memberOf _ + * @since 1.0.0 + * @category Function + * @param {Function} func The function to partially apply arguments to. + * @param {...*} [partials] The arguments to be partially applied. + * @returns {Function} Returns the new partially applied function. + * @example + * + * function greet(greeting, name) { + * return greeting + ' ' + name; + * } + * + * var greetFred = _.partialRight(greet, 'fred'); + * greetFred('hi'); + * // => 'hi fred' + * + * // Partially applied with placeholders. + * var sayHelloTo = _.partialRight(greet, 'hello', _); + * sayHelloTo('fred'); + * // => 'hello fred' + */ + var partialRight = baseRest(function(func, partials) { + var holders = replaceHolders(partials, getHolder(partialRight)); + return createWrap(func, WRAP_PARTIAL_RIGHT_FLAG, undefined, partials, holders); + }); + + /** + * Creates a function that invokes `func` with arguments arranged according + * to the specified `indexes` where the argument value at the first index is + * provided as the first argument, the argument value at the second index is + * provided as the second argument, and so on. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Function + * @param {Function} func The function to rearrange arguments for. + * @param {...(number|number[])} indexes The arranged argument indexes. + * @returns {Function} Returns the new function. + * @example + * + * var rearged = _.rearg(function(a, b, c) { + * return [a, b, c]; + * }, [2, 0, 1]); + * + * rearged('b', 'c', 'a') + * // => ['a', 'b', 'c'] + */ + var rearg = flatRest(function(func, indexes) { + return createWrap(func, WRAP_REARG_FLAG, undefined, undefined, undefined, indexes); + }); + + /** + * Creates a function that invokes `func` with the `this` binding of the + * created function and arguments from `start` and beyond provided as + * an array. + * + * **Note:** This method is based on the + * [rest parameter](https://mdn.io/rest_parameters). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Function + * @param {Function} func The function to apply a rest parameter to. + * @param {number} [start=func.length-1] The start position of the rest parameter. + * @returns {Function} Returns the new function. + * @example + * + * var say = _.rest(function(what, names) { + * return what + ' ' + _.initial(names).join(', ') + + * (_.size(names) > 1 ? ', & ' : '') + _.last(names); + * }); + * + * say('hello', 'fred', 'barney', 'pebbles'); + * // => 'hello fred, barney, & pebbles' + */ + function rest(func, start) { + if (typeof func != 'function') { + throw new TypeError(FUNC_ERROR_TEXT); + } + start = start === undefined ? start : toInteger(start); + return baseRest(func, start); + } + + /** + * Creates a function that invokes `func` with the `this` binding of the + * create function and an array of arguments much like + * [`Function#apply`](http://www.ecma-international.org/ecma-262/7.0/#sec-function.prototype.apply). + * + * **Note:** This method is based on the + * [spread operator](https://mdn.io/spread_operator). + * + * @static + * @memberOf _ + * @since 3.2.0 + * @category Function + * @param {Function} func The function to spread arguments over. + * @param {number} [start=0] The start position of the spread. + * @returns {Function} Returns the new function. + * @example + * + * var say = _.spread(function(who, what) { + * return who + ' says ' + what; + * }); + * + * say(['fred', 'hello']); + * // => 'fred says hello' + * + * var numbers = Promise.all([ + * Promise.resolve(40), + * Promise.resolve(36) + * ]); + * + * numbers.then(_.spread(function(x, y) { + * return x + y; + * })); + * // => a Promise of 76 + */ + function spread(func, start) { + if (typeof func != 'function') { + throw new TypeError(FUNC_ERROR_TEXT); + } + start = start == null ? 0 : nativeMax(toInteger(start), 0); + return baseRest(function(args) { + var array = args[start], + otherArgs = castSlice(args, 0, start); + + if (array) { + arrayPush(otherArgs, array); + } + return apply(func, this, otherArgs); + }); + } + + /** + * Creates a throttled function that only invokes `func` at most once per + * every `wait` milliseconds. The throttled function comes with a `cancel` + * method to cancel delayed `func` invocations and a `flush` method to + * immediately invoke them. Provide `options` to indicate whether `func` + * should be invoked on the leading and/or trailing edge of the `wait` + * timeout. The `func` is invoked with the last arguments provided to the + * throttled function. Subsequent calls to the throttled function return the + * result of the last `func` invocation. + * + * **Note:** If `leading` and `trailing` options are `true`, `func` is + * invoked on the trailing edge of the timeout only if the throttled function + * is invoked more than once during the `wait` timeout. + * + * If `wait` is `0` and `leading` is `false`, `func` invocation is deferred + * until to the next tick, similar to `setTimeout` with a timeout of `0`. + * + * See [David Corbacho's article](https://css-tricks.com/debouncing-throttling-explained-examples/) + * for details over the differences between `_.throttle` and `_.debounce`. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Function + * @param {Function} func The function to throttle. + * @param {number} [wait=0] The number of milliseconds to throttle invocations to. + * @param {Object} [options={}] The options object. + * @param {boolean} [options.leading=true] + * Specify invoking on the leading edge of the timeout. + * @param {boolean} [options.trailing=true] + * Specify invoking on the trailing edge of the timeout. + * @returns {Function} Returns the new throttled function. + * @example + * + * // Avoid excessively updating the position while scrolling. + * jQuery(window).on('scroll', _.throttle(updatePosition, 100)); + * + * // Invoke `renewToken` when the click event is fired, but not more than once every 5 minutes. + * var throttled = _.throttle(renewToken, 300000, { 'trailing': false }); + * jQuery(element).on('click', throttled); + * + * // Cancel the trailing throttled invocation. + * jQuery(window).on('popstate', throttled.cancel); + */ + function throttle(func, wait, options) { + var leading = true, + trailing = true; + + if (typeof func != 'function') { + throw new TypeError(FUNC_ERROR_TEXT); + } + if (isObject(options)) { + leading = 'leading' in options ? !!options.leading : leading; + trailing = 'trailing' in options ? !!options.trailing : trailing; + } + return debounce(func, wait, { + 'leading': leading, + 'maxWait': wait, + 'trailing': trailing + }); + } + + /** + * Creates a function that accepts up to one argument, ignoring any + * additional arguments. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Function + * @param {Function} func The function to cap arguments for. + * @returns {Function} Returns the new capped function. + * @example + * + * _.map(['6', '8', '10'], _.unary(parseInt)); + * // => [6, 8, 10] + */ + function unary(func) { + return ary(func, 1); + } + + /** + * Creates a function that provides `value` to `wrapper` as its first + * argument. Any additional arguments provided to the function are appended + * to those provided to the `wrapper`. The wrapper is invoked with the `this` + * binding of the created function. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Function + * @param {*} value The value to wrap. + * @param {Function} [wrapper=identity] The wrapper function. + * @returns {Function} Returns the new function. + * @example + * + * var p = _.wrap(_.escape, function(func, text) { + * return '

' + func(text) + '

'; + * }); + * + * p('fred, barney, & pebbles'); + * // => '

fred, barney, & pebbles

' + */ + function wrap(value, wrapper) { + return partial(castFunction(wrapper), value); + } + + /*------------------------------------------------------------------------*/ + + /** + * Casts `value` as an array if it's not one. + * + * @static + * @memberOf _ + * @since 4.4.0 + * @category Lang + * @param {*} value The value to inspect. + * @returns {Array} Returns the cast array. + * @example + * + * _.castArray(1); + * // => [1] + * + * _.castArray({ 'a': 1 }); + * // => [{ 'a': 1 }] + * + * _.castArray('abc'); + * // => ['abc'] + * + * _.castArray(null); + * // => [null] + * + * _.castArray(undefined); + * // => [undefined] + * + * _.castArray(); + * // => [] + * + * var array = [1, 2, 3]; + * console.log(_.castArray(array) === array); + * // => true + */ + function castArray() { + if (!arguments.length) { + return []; + } + var value = arguments[0]; + return isArray(value) ? value : [value]; + } + + /** + * Creates a shallow clone of `value`. + * + * **Note:** This method is loosely based on the + * [structured clone algorithm](https://mdn.io/Structured_clone_algorithm) + * and supports cloning arrays, array buffers, booleans, date objects, maps, + * numbers, `Object` objects, regexes, sets, strings, symbols, and typed + * arrays. The own enumerable properties of `arguments` objects are cloned + * as plain objects. An empty object is returned for uncloneable values such + * as error objects, functions, DOM nodes, and WeakMaps. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to clone. + * @returns {*} Returns the cloned value. + * @see _.cloneDeep + * @example + * + * var objects = [{ 'a': 1 }, { 'b': 2 }]; + * + * var shallow = _.clone(objects); + * console.log(shallow[0] === objects[0]); + * // => true + */ + function clone(value) { + return baseClone(value, CLONE_SYMBOLS_FLAG); + } + + /** + * This method is like `_.clone` except that it accepts `customizer` which + * is invoked to produce the cloned value. If `customizer` returns `undefined`, + * cloning is handled by the method instead. The `customizer` is invoked with + * up to four arguments; (value [, index|key, object, stack]). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Lang + * @param {*} value The value to clone. + * @param {Function} [customizer] The function to customize cloning. + * @returns {*} Returns the cloned value. + * @see _.cloneDeepWith + * @example + * + * function customizer(value) { + * if (_.isElement(value)) { + * return value.cloneNode(false); + * } + * } + * + * var el = _.cloneWith(document.body, customizer); + * + * console.log(el === document.body); + * // => false + * console.log(el.nodeName); + * // => 'BODY' + * console.log(el.childNodes.length); + * // => 0 + */ + function cloneWith(value, customizer) { + customizer = typeof customizer == 'function' ? customizer : undefined; + return baseClone(value, CLONE_SYMBOLS_FLAG, customizer); + } + + /** + * This method is like `_.clone` except that it recursively clones `value`. + * + * @static + * @memberOf _ + * @since 1.0.0 + * @category Lang + * @param {*} value The value to recursively clone. + * @returns {*} Returns the deep cloned value. + * @see _.clone + * @example + * + * var objects = [{ 'a': 1 }, { 'b': 2 }]; + * + * var deep = _.cloneDeep(objects); + * console.log(deep[0] === objects[0]); + * // => false + */ + function cloneDeep(value) { + return baseClone(value, CLONE_DEEP_FLAG | CLONE_SYMBOLS_FLAG); + } + + /** + * This method is like `_.cloneWith` except that it recursively clones `value`. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Lang + * @param {*} value The value to recursively clone. + * @param {Function} [customizer] The function to customize cloning. + * @returns {*} Returns the deep cloned value. + * @see _.cloneWith + * @example + * + * function customizer(value) { + * if (_.isElement(value)) { + * return value.cloneNode(true); + * } + * } + * + * var el = _.cloneDeepWith(document.body, customizer); + * + * console.log(el === document.body); + * // => false + * console.log(el.nodeName); + * // => 'BODY' + * console.log(el.childNodes.length); + * // => 20 + */ + function cloneDeepWith(value, customizer) { + customizer = typeof customizer == 'function' ? customizer : undefined; + return baseClone(value, CLONE_DEEP_FLAG | CLONE_SYMBOLS_FLAG, customizer); + } + + /** + * Checks if `object` conforms to `source` by invoking the predicate + * properties of `source` with the corresponding property values of `object`. + * + * **Note:** This method is equivalent to `_.conforms` when `source` is + * partially applied. + * + * @static + * @memberOf _ + * @since 4.14.0 + * @category Lang + * @param {Object} object The object to inspect. + * @param {Object} source The object of property predicates to conform to. + * @returns {boolean} Returns `true` if `object` conforms, else `false`. + * @example + * + * var object = { 'a': 1, 'b': 2 }; + * + * _.conformsTo(object, { 'b': function(n) { return n > 1; } }); + * // => true + * + * _.conformsTo(object, { 'b': function(n) { return n > 2; } }); + * // => false + */ + function conformsTo(object, source) { + return source == null || baseConformsTo(object, source, keys(source)); + } + + /** + * Performs a + * [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero) + * comparison between two values to determine if they are equivalent. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Lang + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @returns {boolean} Returns `true` if the values are equivalent, else `false`. + * @example + * + * var object = { 'a': 1 }; + * var other = { 'a': 1 }; + * + * _.eq(object, object); + * // => true + * + * _.eq(object, other); + * // => false + * + * _.eq('a', 'a'); + * // => true + * + * _.eq('a', Object('a')); + * // => false + * + * _.eq(NaN, NaN); + * // => true + */ + function eq(value, other) { + return value === other || (value !== value && other !== other); + } + + /** + * Checks if `value` is greater than `other`. + * + * @static + * @memberOf _ + * @since 3.9.0 + * @category Lang + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @returns {boolean} Returns `true` if `value` is greater than `other`, + * else `false`. + * @see _.lt + * @example + * + * _.gt(3, 1); + * // => true + * + * _.gt(3, 3); + * // => false + * + * _.gt(1, 3); + * // => false + */ + var gt = createRelationalOperation(baseGt); + + /** + * Checks if `value` is greater than or equal to `other`. + * + * @static + * @memberOf _ + * @since 3.9.0 + * @category Lang + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @returns {boolean} Returns `true` if `value` is greater than or equal to + * `other`, else `false`. + * @see _.lte + * @example + * + * _.gte(3, 1); + * // => true + * + * _.gte(3, 3); + * // => true + * + * _.gte(1, 3); + * // => false + */ + var gte = createRelationalOperation(function(value, other) { + return value >= other; + }); + + /** + * Checks if `value` is likely an `arguments` object. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is an `arguments` object, + * else `false`. + * @example + * + * _.isArguments(function() { return arguments; }()); + * // => true + * + * _.isArguments([1, 2, 3]); + * // => false + */ + var isArguments = baseIsArguments(function() { return arguments; }()) ? baseIsArguments : function(value) { + return isObjectLike(value) && hasOwnProperty.call(value, 'callee') && + !propertyIsEnumerable.call(value, 'callee'); + }; + + /** + * Checks if `value` is classified as an `Array` object. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is an array, else `false`. + * @example + * + * _.isArray([1, 2, 3]); + * // => true + * + * _.isArray(document.body.children); + * // => false + * + * _.isArray('abc'); + * // => false + * + * _.isArray(_.noop); + * // => false + */ + var isArray = Array.isArray; + + /** + * Checks if `value` is classified as an `ArrayBuffer` object. + * + * @static + * @memberOf _ + * @since 4.3.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is an array buffer, else `false`. + * @example + * + * _.isArrayBuffer(new ArrayBuffer(2)); + * // => true + * + * _.isArrayBuffer(new Array(2)); + * // => false + */ + var isArrayBuffer = nodeIsArrayBuffer ? baseUnary(nodeIsArrayBuffer) : baseIsArrayBuffer; + + /** + * Checks if `value` is array-like. A value is considered array-like if it's + * not a function and has a `value.length` that's an integer greater than or + * equal to `0` and less than or equal to `Number.MAX_SAFE_INTEGER`. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is array-like, else `false`. + * @example + * + * _.isArrayLike([1, 2, 3]); + * // => true + * + * _.isArrayLike(document.body.children); + * // => true + * + * _.isArrayLike('abc'); + * // => true + * + * _.isArrayLike(_.noop); + * // => false + */ + function isArrayLike(value) { + return value != null && isLength(value.length) && !isFunction(value); + } + + /** + * This method is like `_.isArrayLike` except that it also checks if `value` + * is an object. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is an array-like object, + * else `false`. + * @example + * + * _.isArrayLikeObject([1, 2, 3]); + * // => true + * + * _.isArrayLikeObject(document.body.children); + * // => true + * + * _.isArrayLikeObject('abc'); + * // => false + * + * _.isArrayLikeObject(_.noop); + * // => false + */ + function isArrayLikeObject(value) { + return isObjectLike(value) && isArrayLike(value); + } + + /** + * Checks if `value` is classified as a boolean primitive or object. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a boolean, else `false`. + * @example + * + * _.isBoolean(false); + * // => true + * + * _.isBoolean(null); + * // => false + */ + function isBoolean(value) { + return value === true || value === false || + (isObjectLike(value) && baseGetTag(value) == boolTag); + } + + /** + * Checks if `value` is a buffer. + * + * @static + * @memberOf _ + * @since 4.3.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a buffer, else `false`. + * @example + * + * _.isBuffer(new Buffer(2)); + * // => true + * + * _.isBuffer(new Uint8Array(2)); + * // => false + */ + var isBuffer = nativeIsBuffer || stubFalse; + + /** + * Checks if `value` is classified as a `Date` object. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a date object, else `false`. + * @example + * + * _.isDate(new Date); + * // => true + * + * _.isDate('Mon April 23 2012'); + * // => false + */ + var isDate = nodeIsDate ? baseUnary(nodeIsDate) : baseIsDate; + + /** + * Checks if `value` is likely a DOM element. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a DOM element, else `false`. + * @example + * + * _.isElement(document.body); + * // => true + * + * _.isElement(''); + * // => false + */ + function isElement(value) { + return isObjectLike(value) && value.nodeType === 1 && !isPlainObject(value); + } + + /** + * Checks if `value` is an empty object, collection, map, or set. + * + * Objects are considered empty if they have no own enumerable string keyed + * properties. + * + * Array-like values such as `arguments` objects, arrays, buffers, strings, or + * jQuery-like collections are considered empty if they have a `length` of `0`. + * Similarly, maps and sets are considered empty if they have a `size` of `0`. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is empty, else `false`. + * @example + * + * _.isEmpty(null); + * // => true + * + * _.isEmpty(true); + * // => true + * + * _.isEmpty(1); + * // => true + * + * _.isEmpty([1, 2, 3]); + * // => false + * + * _.isEmpty({ 'a': 1 }); + * // => false + */ + function isEmpty(value) { + if (value == null) { + return true; + } + if (isArrayLike(value) && + (isArray(value) || typeof value == 'string' || typeof value.splice == 'function' || + isBuffer(value) || isTypedArray(value) || isArguments(value))) { + return !value.length; + } + var tag = getTag(value); + if (tag == mapTag || tag == setTag) { + return !value.size; + } + if (isPrototype(value)) { + return !baseKeys(value).length; + } + for (var key in value) { + if (hasOwnProperty.call(value, key)) { + return false; + } + } + return true; + } + + /** + * Performs a deep comparison between two values to determine if they are + * equivalent. + * + * **Note:** This method supports comparing arrays, array buffers, booleans, + * date objects, error objects, maps, numbers, `Object` objects, regexes, + * sets, strings, symbols, and typed arrays. `Object` objects are compared + * by their own, not inherited, enumerable properties. Functions and DOM + * nodes are compared by strict equality, i.e. `===`. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @returns {boolean} Returns `true` if the values are equivalent, else `false`. + * @example + * + * var object = { 'a': 1 }; + * var other = { 'a': 1 }; + * + * _.isEqual(object, other); + * // => true + * + * object === other; + * // => false + */ + function isEqual(value, other) { + return baseIsEqual(value, other); + } + + /** + * This method is like `_.isEqual` except that it accepts `customizer` which + * is invoked to compare values. If `customizer` returns `undefined`, comparisons + * are handled by the method instead. The `customizer` is invoked with up to + * six arguments: (objValue, othValue [, index|key, object, other, stack]). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Lang + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @param {Function} [customizer] The function to customize comparisons. + * @returns {boolean} Returns `true` if the values are equivalent, else `false`. + * @example + * + * function isGreeting(value) { + * return /^h(?:i|ello)$/.test(value); + * } + * + * function customizer(objValue, othValue) { + * if (isGreeting(objValue) && isGreeting(othValue)) { + * return true; + * } + * } + * + * var array = ['hello', 'goodbye']; + * var other = ['hi', 'goodbye']; + * + * _.isEqualWith(array, other, customizer); + * // => true + */ + function isEqualWith(value, other, customizer) { + customizer = typeof customizer == 'function' ? customizer : undefined; + var result = customizer ? customizer(value, other) : undefined; + return result === undefined ? baseIsEqual(value, other, undefined, customizer) : !!result; + } + + /** + * Checks if `value` is an `Error`, `EvalError`, `RangeError`, `ReferenceError`, + * `SyntaxError`, `TypeError`, or `URIError` object. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is an error object, else `false`. + * @example + * + * _.isError(new Error); + * // => true + * + * _.isError(Error); + * // => false + */ + function isError(value) { + if (!isObjectLike(value)) { + return false; + } + var tag = baseGetTag(value); + return tag == errorTag || tag == domExcTag || + (typeof value.message == 'string' && typeof value.name == 'string' && !isPlainObject(value)); + } + + /** + * Checks if `value` is a finite primitive number. + * + * **Note:** This method is based on + * [`Number.isFinite`](https://mdn.io/Number/isFinite). + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a finite number, else `false`. + * @example + * + * _.isFinite(3); + * // => true + * + * _.isFinite(Number.MIN_VALUE); + * // => true + * + * _.isFinite(Infinity); + * // => false + * + * _.isFinite('3'); + * // => false + */ + function isFinite(value) { + return typeof value == 'number' && nativeIsFinite(value); + } + + /** + * Checks if `value` is classified as a `Function` object. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a function, else `false`. + * @example + * + * _.isFunction(_); + * // => true + * + * _.isFunction(/abc/); + * // => false + */ + function isFunction(value) { + if (!isObject(value)) { + return false; + } + // The use of `Object#toString` avoids issues with the `typeof` operator + // in Safari 9 which returns 'object' for typed arrays and other constructors. + var tag = baseGetTag(value); + return tag == funcTag || tag == genTag || tag == asyncTag || tag == proxyTag; + } + + /** + * Checks if `value` is an integer. + * + * **Note:** This method is based on + * [`Number.isInteger`](https://mdn.io/Number/isInteger). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is an integer, else `false`. + * @example + * + * _.isInteger(3); + * // => true + * + * _.isInteger(Number.MIN_VALUE); + * // => false + * + * _.isInteger(Infinity); + * // => false + * + * _.isInteger('3'); + * // => false + */ + function isInteger(value) { + return typeof value == 'number' && value == toInteger(value); + } + + /** + * Checks if `value` is a valid array-like length. + * + * **Note:** This method is loosely based on + * [`ToLength`](http://ecma-international.org/ecma-262/7.0/#sec-tolength). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a valid length, else `false`. + * @example + * + * _.isLength(3); + * // => true + * + * _.isLength(Number.MIN_VALUE); + * // => false + * + * _.isLength(Infinity); + * // => false + * + * _.isLength('3'); + * // => false + */ + function isLength(value) { + return typeof value == 'number' && + value > -1 && value % 1 == 0 && value <= MAX_SAFE_INTEGER; + } + + /** + * Checks if `value` is the + * [language type](http://www.ecma-international.org/ecma-262/7.0/#sec-ecmascript-language-types) + * of `Object`. (e.g. arrays, functions, objects, regexes, `new Number(0)`, and `new String('')`) + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is an object, else `false`. + * @example + * + * _.isObject({}); + * // => true + * + * _.isObject([1, 2, 3]); + * // => true + * + * _.isObject(_.noop); + * // => true + * + * _.isObject(null); + * // => false + */ + function isObject(value) { + var type = typeof value; + return value != null && (type == 'object' || type == 'function'); + } + + /** + * Checks if `value` is object-like. A value is object-like if it's not `null` + * and has a `typeof` result of "object". + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is object-like, else `false`. + * @example + * + * _.isObjectLike({}); + * // => true + * + * _.isObjectLike([1, 2, 3]); + * // => true + * + * _.isObjectLike(_.noop); + * // => false + * + * _.isObjectLike(null); + * // => false + */ + function isObjectLike(value) { + return value != null && typeof value == 'object'; + } + + /** + * Checks if `value` is classified as a `Map` object. + * + * @static + * @memberOf _ + * @since 4.3.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a map, else `false`. + * @example + * + * _.isMap(new Map); + * // => true + * + * _.isMap(new WeakMap); + * // => false + */ + var isMap = nodeIsMap ? baseUnary(nodeIsMap) : baseIsMap; + + /** + * Performs a partial deep comparison between `object` and `source` to + * determine if `object` contains equivalent property values. + * + * **Note:** This method is equivalent to `_.matches` when `source` is + * partially applied. + * + * Partial comparisons will match empty array and empty object `source` + * values against any array or object value, respectively. See `_.isEqual` + * for a list of supported value comparisons. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Lang + * @param {Object} object The object to inspect. + * @param {Object} source The object of property values to match. + * @returns {boolean} Returns `true` if `object` is a match, else `false`. + * @example + * + * var object = { 'a': 1, 'b': 2 }; + * + * _.isMatch(object, { 'b': 2 }); + * // => true + * + * _.isMatch(object, { 'b': 1 }); + * // => false + */ + function isMatch(object, source) { + return object === source || baseIsMatch(object, source, getMatchData(source)); + } + + /** + * This method is like `_.isMatch` except that it accepts `customizer` which + * is invoked to compare values. If `customizer` returns `undefined`, comparisons + * are handled by the method instead. The `customizer` is invoked with five + * arguments: (objValue, srcValue, index|key, object, source). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Lang + * @param {Object} object The object to inspect. + * @param {Object} source The object of property values to match. + * @param {Function} [customizer] The function to customize comparisons. + * @returns {boolean} Returns `true` if `object` is a match, else `false`. + * @example + * + * function isGreeting(value) { + * return /^h(?:i|ello)$/.test(value); + * } + * + * function customizer(objValue, srcValue) { + * if (isGreeting(objValue) && isGreeting(srcValue)) { + * return true; + * } + * } + * + * var object = { 'greeting': 'hello' }; + * var source = { 'greeting': 'hi' }; + * + * _.isMatchWith(object, source, customizer); + * // => true + */ + function isMatchWith(object, source, customizer) { + customizer = typeof customizer == 'function' ? customizer : undefined; + return baseIsMatch(object, source, getMatchData(source), customizer); + } + + /** + * Checks if `value` is `NaN`. + * + * **Note:** This method is based on + * [`Number.isNaN`](https://mdn.io/Number/isNaN) and is not the same as + * global [`isNaN`](https://mdn.io/isNaN) which returns `true` for + * `undefined` and other non-number values. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is `NaN`, else `false`. + * @example + * + * _.isNaN(NaN); + * // => true + * + * _.isNaN(new Number(NaN)); + * // => true + * + * isNaN(undefined); + * // => true + * + * _.isNaN(undefined); + * // => false + */ + function isNaN(value) { + // An `NaN` primitive is the only value that is not equal to itself. + // Perform the `toStringTag` check first to avoid errors with some + // ActiveX objects in IE. + return isNumber(value) && value != +value; + } + + /** + * Checks if `value` is a pristine native function. + * + * **Note:** This method can't reliably detect native functions in the presence + * of the core-js package because core-js circumvents this kind of detection. + * Despite multiple requests, the core-js maintainer has made it clear: any + * attempt to fix the detection will be obstructed. As a result, we're left + * with little choice but to throw an error. Unfortunately, this also affects + * packages, like [babel-polyfill](https://www.npmjs.com/package/babel-polyfill), + * which rely on core-js. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a native function, + * else `false`. + * @example + * + * _.isNative(Array.prototype.push); + * // => true + * + * _.isNative(_); + * // => false + */ + function isNative(value) { + if (isMaskable(value)) { + throw new Error(CORE_ERROR_TEXT); + } + return baseIsNative(value); + } + + /** + * Checks if `value` is `null`. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is `null`, else `false`. + * @example + * + * _.isNull(null); + * // => true + * + * _.isNull(void 0); + * // => false + */ + function isNull(value) { + return value === null; + } + + /** + * Checks if `value` is `null` or `undefined`. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is nullish, else `false`. + * @example + * + * _.isNil(null); + * // => true + * + * _.isNil(void 0); + * // => true + * + * _.isNil(NaN); + * // => false + */ + function isNil(value) { + return value == null; + } + + /** + * Checks if `value` is classified as a `Number` primitive or object. + * + * **Note:** To exclude `Infinity`, `-Infinity`, and `NaN`, which are + * classified as numbers, use the `_.isFinite` method. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a number, else `false`. + * @example + * + * _.isNumber(3); + * // => true + * + * _.isNumber(Number.MIN_VALUE); + * // => true + * + * _.isNumber(Infinity); + * // => true + * + * _.isNumber('3'); + * // => false + */ + function isNumber(value) { + return typeof value == 'number' || + (isObjectLike(value) && baseGetTag(value) == numberTag); + } + + /** + * Checks if `value` is a plain object, that is, an object created by the + * `Object` constructor or one with a `[[Prototype]]` of `null`. + * + * @static + * @memberOf _ + * @since 0.8.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a plain object, else `false`. + * @example + * + * function Foo() { + * this.a = 1; + * } + * + * _.isPlainObject(new Foo); + * // => false + * + * _.isPlainObject([1, 2, 3]); + * // => false + * + * _.isPlainObject({ 'x': 0, 'y': 0 }); + * // => true + * + * _.isPlainObject(Object.create(null)); + * // => true + */ + function isPlainObject(value) { + if (!isObjectLike(value) || baseGetTag(value) != objectTag) { + return false; + } + var proto = getPrototype(value); + if (proto === null) { + return true; + } + var Ctor = hasOwnProperty.call(proto, 'constructor') && proto.constructor; + return typeof Ctor == 'function' && Ctor instanceof Ctor && + funcToString.call(Ctor) == objectCtorString; + } + + /** + * Checks if `value` is classified as a `RegExp` object. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a regexp, else `false`. + * @example + * + * _.isRegExp(/abc/); + * // => true + * + * _.isRegExp('/abc/'); + * // => false + */ + var isRegExp = nodeIsRegExp ? baseUnary(nodeIsRegExp) : baseIsRegExp; + + /** + * Checks if `value` is a safe integer. An integer is safe if it's an IEEE-754 + * double precision number which isn't the result of a rounded unsafe integer. + * + * **Note:** This method is based on + * [`Number.isSafeInteger`](https://mdn.io/Number/isSafeInteger). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a safe integer, else `false`. + * @example + * + * _.isSafeInteger(3); + * // => true + * + * _.isSafeInteger(Number.MIN_VALUE); + * // => false + * + * _.isSafeInteger(Infinity); + * // => false + * + * _.isSafeInteger('3'); + * // => false + */ + function isSafeInteger(value) { + return isInteger(value) && value >= -MAX_SAFE_INTEGER && value <= MAX_SAFE_INTEGER; + } + + /** + * Checks if `value` is classified as a `Set` object. + * + * @static + * @memberOf _ + * @since 4.3.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a set, else `false`. + * @example + * + * _.isSet(new Set); + * // => true + * + * _.isSet(new WeakSet); + * // => false + */ + var isSet = nodeIsSet ? baseUnary(nodeIsSet) : baseIsSet; + + /** + * Checks if `value` is classified as a `String` primitive or object. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a string, else `false`. + * @example + * + * _.isString('abc'); + * // => true + * + * _.isString(1); + * // => false + */ + function isString(value) { + return typeof value == 'string' || + (!isArray(value) && isObjectLike(value) && baseGetTag(value) == stringTag); + } + + /** + * Checks if `value` is classified as a `Symbol` primitive or object. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a symbol, else `false`. + * @example + * + * _.isSymbol(Symbol.iterator); + * // => true + * + * _.isSymbol('abc'); + * // => false + */ + function isSymbol(value) { + return typeof value == 'symbol' || + (isObjectLike(value) && baseGetTag(value) == symbolTag); + } + + /** + * Checks if `value` is classified as a typed array. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a typed array, else `false`. + * @example + * + * _.isTypedArray(new Uint8Array); + * // => true + * + * _.isTypedArray([]); + * // => false + */ + var isTypedArray = nodeIsTypedArray ? baseUnary(nodeIsTypedArray) : baseIsTypedArray; + + /** + * Checks if `value` is `undefined`. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is `undefined`, else `false`. + * @example + * + * _.isUndefined(void 0); + * // => true + * + * _.isUndefined(null); + * // => false + */ + function isUndefined(value) { + return value === undefined; + } + + /** + * Checks if `value` is classified as a `WeakMap` object. + * + * @static + * @memberOf _ + * @since 4.3.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a weak map, else `false`. + * @example + * + * _.isWeakMap(new WeakMap); + * // => true + * + * _.isWeakMap(new Map); + * // => false + */ + function isWeakMap(value) { + return isObjectLike(value) && getTag(value) == weakMapTag; + } + + /** + * Checks if `value` is classified as a `WeakSet` object. + * + * @static + * @memberOf _ + * @since 4.3.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a weak set, else `false`. + * @example + * + * _.isWeakSet(new WeakSet); + * // => true + * + * _.isWeakSet(new Set); + * // => false + */ + function isWeakSet(value) { + return isObjectLike(value) && baseGetTag(value) == weakSetTag; + } + + /** + * Checks if `value` is less than `other`. + * + * @static + * @memberOf _ + * @since 3.9.0 + * @category Lang + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @returns {boolean} Returns `true` if `value` is less than `other`, + * else `false`. + * @see _.gt + * @example + * + * _.lt(1, 3); + * // => true + * + * _.lt(3, 3); + * // => false + * + * _.lt(3, 1); + * // => false + */ + var lt = createRelationalOperation(baseLt); + + /** + * Checks if `value` is less than or equal to `other`. + * + * @static + * @memberOf _ + * @since 3.9.0 + * @category Lang + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @returns {boolean} Returns `true` if `value` is less than or equal to + * `other`, else `false`. + * @see _.gte + * @example + * + * _.lte(1, 3); + * // => true + * + * _.lte(3, 3); + * // => true + * + * _.lte(3, 1); + * // => false + */ + var lte = createRelationalOperation(function(value, other) { + return value <= other; + }); + + /** + * Converts `value` to an array. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category Lang + * @param {*} value The value to convert. + * @returns {Array} Returns the converted array. + * @example + * + * _.toArray({ 'a': 1, 'b': 2 }); + * // => [1, 2] + * + * _.toArray('abc'); + * // => ['a', 'b', 'c'] + * + * _.toArray(1); + * // => [] + * + * _.toArray(null); + * // => [] + */ + function toArray(value) { + if (!value) { + return []; + } + if (isArrayLike(value)) { + return isString(value) ? stringToArray(value) : copyArray(value); + } + if (symIterator && value[symIterator]) { + return iteratorToArray(value[symIterator]()); + } + var tag = getTag(value), + func = tag == mapTag ? mapToArray : (tag == setTag ? setToArray : values); + + return func(value); + } + + /** + * Converts `value` to a finite number. + * + * @static + * @memberOf _ + * @since 4.12.0 + * @category Lang + * @param {*} value The value to convert. + * @returns {number} Returns the converted number. + * @example + * + * _.toFinite(3.2); + * // => 3.2 + * + * _.toFinite(Number.MIN_VALUE); + * // => 5e-324 + * + * _.toFinite(Infinity); + * // => 1.7976931348623157e+308 + * + * _.toFinite('3.2'); + * // => 3.2 + */ + function toFinite(value) { + if (!value) { + return value === 0 ? value : 0; + } + value = toNumber(value); + if (value === INFINITY || value === -INFINITY) { + var sign = (value < 0 ? -1 : 1); + return sign * MAX_INTEGER; + } + return value === value ? value : 0; + } + + /** + * Converts `value` to an integer. + * + * **Note:** This method is loosely based on + * [`ToInteger`](http://www.ecma-international.org/ecma-262/7.0/#sec-tointeger). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Lang + * @param {*} value The value to convert. + * @returns {number} Returns the converted integer. + * @example + * + * _.toInteger(3.2); + * // => 3 + * + * _.toInteger(Number.MIN_VALUE); + * // => 0 + * + * _.toInteger(Infinity); + * // => 1.7976931348623157e+308 + * + * _.toInteger('3.2'); + * // => 3 + */ + function toInteger(value) { + var result = toFinite(value), + remainder = result % 1; + + return result === result ? (remainder ? result - remainder : result) : 0; + } + + /** + * Converts `value` to an integer suitable for use as the length of an + * array-like object. + * + * **Note:** This method is based on + * [`ToLength`](http://ecma-international.org/ecma-262/7.0/#sec-tolength). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Lang + * @param {*} value The value to convert. + * @returns {number} Returns the converted integer. + * @example + * + * _.toLength(3.2); + * // => 3 + * + * _.toLength(Number.MIN_VALUE); + * // => 0 + * + * _.toLength(Infinity); + * // => 4294967295 + * + * _.toLength('3.2'); + * // => 3 + */ + function toLength(value) { + return value ? baseClamp(toInteger(value), 0, MAX_ARRAY_LENGTH) : 0; + } + + /** + * Converts `value` to a number. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Lang + * @param {*} value The value to process. + * @returns {number} Returns the number. + * @example + * + * _.toNumber(3.2); + * // => 3.2 + * + * _.toNumber(Number.MIN_VALUE); + * // => 5e-324 + * + * _.toNumber(Infinity); + * // => Infinity + * + * _.toNumber('3.2'); + * // => 3.2 + */ + function toNumber(value) { + if (typeof value == 'number') { + return value; + } + if (isSymbol(value)) { + return NAN; + } + if (isObject(value)) { + var other = typeof value.valueOf == 'function' ? value.valueOf() : value; + value = isObject(other) ? (other + '') : other; + } + if (typeof value != 'string') { + return value === 0 ? value : +value; + } + value = value.replace(reTrim, ''); + var isBinary = reIsBinary.test(value); + return (isBinary || reIsOctal.test(value)) + ? freeParseInt(value.slice(2), isBinary ? 2 : 8) + : (reIsBadHex.test(value) ? NAN : +value); + } + + /** + * Converts `value` to a plain object flattening inherited enumerable string + * keyed properties of `value` to own properties of the plain object. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Lang + * @param {*} value The value to convert. + * @returns {Object} Returns the converted plain object. + * @example + * + * function Foo() { + * this.b = 2; + * } + * + * Foo.prototype.c = 3; + * + * _.assign({ 'a': 1 }, new Foo); + * // => { 'a': 1, 'b': 2 } + * + * _.assign({ 'a': 1 }, _.toPlainObject(new Foo)); + * // => { 'a': 1, 'b': 2, 'c': 3 } + */ + function toPlainObject(value) { + return copyObject(value, keysIn(value)); + } + + /** + * Converts `value` to a safe integer. A safe integer can be compared and + * represented correctly. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Lang + * @param {*} value The value to convert. + * @returns {number} Returns the converted integer. + * @example + * + * _.toSafeInteger(3.2); + * // => 3 + * + * _.toSafeInteger(Number.MIN_VALUE); + * // => 0 + * + * _.toSafeInteger(Infinity); + * // => 9007199254740991 + * + * _.toSafeInteger('3.2'); + * // => 3 + */ + function toSafeInteger(value) { + return value + ? baseClamp(toInteger(value), -MAX_SAFE_INTEGER, MAX_SAFE_INTEGER) + : (value === 0 ? value : 0); + } + + /** + * Converts `value` to a string. An empty string is returned for `null` + * and `undefined` values. The sign of `-0` is preserved. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Lang + * @param {*} value The value to convert. + * @returns {string} Returns the converted string. + * @example + * + * _.toString(null); + * // => '' + * + * _.toString(-0); + * // => '-0' + * + * _.toString([1, 2, 3]); + * // => '1,2,3' + */ + function toString(value) { + return value == null ? '' : baseToString(value); + } + + /*------------------------------------------------------------------------*/ + + /** + * Assigns own enumerable string keyed properties of source objects to the + * destination object. Source objects are applied from left to right. + * Subsequent sources overwrite property assignments of previous sources. + * + * **Note:** This method mutates `object` and is loosely based on + * [`Object.assign`](https://mdn.io/Object/assign). + * + * @static + * @memberOf _ + * @since 0.10.0 + * @category Object + * @param {Object} object The destination object. + * @param {...Object} [sources] The source objects. + * @returns {Object} Returns `object`. + * @see _.assignIn + * @example + * + * function Foo() { + * this.a = 1; + * } + * + * function Bar() { + * this.c = 3; + * } + * + * Foo.prototype.b = 2; + * Bar.prototype.d = 4; + * + * _.assign({ 'a': 0 }, new Foo, new Bar); + * // => { 'a': 1, 'c': 3 } + */ + var assign = createAssigner(function(object, source) { + if (isPrototype(source) || isArrayLike(source)) { + copyObject(source, keys(source), object); + return; + } + for (var key in source) { + if (hasOwnProperty.call(source, key)) { + assignValue(object, key, source[key]); + } + } + }); + + /** + * This method is like `_.assign` except that it iterates over own and + * inherited source properties. + * + * **Note:** This method mutates `object`. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @alias extend + * @category Object + * @param {Object} object The destination object. + * @param {...Object} [sources] The source objects. + * @returns {Object} Returns `object`. + * @see _.assign + * @example + * + * function Foo() { + * this.a = 1; + * } + * + * function Bar() { + * this.c = 3; + * } + * + * Foo.prototype.b = 2; + * Bar.prototype.d = 4; + * + * _.assignIn({ 'a': 0 }, new Foo, new Bar); + * // => { 'a': 1, 'b': 2, 'c': 3, 'd': 4 } + */ + var assignIn = createAssigner(function(object, source) { + copyObject(source, keysIn(source), object); + }); + + /** + * This method is like `_.assignIn` except that it accepts `customizer` + * which is invoked to produce the assigned values. If `customizer` returns + * `undefined`, assignment is handled by the method instead. The `customizer` + * is invoked with five arguments: (objValue, srcValue, key, object, source). + * + * **Note:** This method mutates `object`. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @alias extendWith + * @category Object + * @param {Object} object The destination object. + * @param {...Object} sources The source objects. + * @param {Function} [customizer] The function to customize assigned values. + * @returns {Object} Returns `object`. + * @see _.assignWith + * @example + * + * function customizer(objValue, srcValue) { + * return _.isUndefined(objValue) ? srcValue : objValue; + * } + * + * var defaults = _.partialRight(_.assignInWith, customizer); + * + * defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 }); + * // => { 'a': 1, 'b': 2 } + */ + var assignInWith = createAssigner(function(object, source, srcIndex, customizer) { + copyObject(source, keysIn(source), object, customizer); + }); + + /** + * This method is like `_.assign` except that it accepts `customizer` + * which is invoked to produce the assigned values. If `customizer` returns + * `undefined`, assignment is handled by the method instead. The `customizer` + * is invoked with five arguments: (objValue, srcValue, key, object, source). + * + * **Note:** This method mutates `object`. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Object + * @param {Object} object The destination object. + * @param {...Object} sources The source objects. + * @param {Function} [customizer] The function to customize assigned values. + * @returns {Object} Returns `object`. + * @see _.assignInWith + * @example + * + * function customizer(objValue, srcValue) { + * return _.isUndefined(objValue) ? srcValue : objValue; + * } + * + * var defaults = _.partialRight(_.assignWith, customizer); + * + * defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 }); + * // => { 'a': 1, 'b': 2 } + */ + var assignWith = createAssigner(function(object, source, srcIndex, customizer) { + copyObject(source, keys(source), object, customizer); + }); + + /** + * Creates an array of values corresponding to `paths` of `object`. + * + * @static + * @memberOf _ + * @since 1.0.0 + * @category Object + * @param {Object} object The object to iterate over. + * @param {...(string|string[])} [paths] The property paths to pick. + * @returns {Array} Returns the picked values. + * @example + * + * var object = { 'a': [{ 'b': { 'c': 3 } }, 4] }; + * + * _.at(object, ['a[0].b.c', 'a[1]']); + * // => [3, 4] + */ + var at = flatRest(baseAt); + + /** + * Creates an object that inherits from the `prototype` object. If a + * `properties` object is given, its own enumerable string keyed properties + * are assigned to the created object. + * + * @static + * @memberOf _ + * @since 2.3.0 + * @category Object + * @param {Object} prototype The object to inherit from. + * @param {Object} [properties] The properties to assign to the object. + * @returns {Object} Returns the new object. + * @example + * + * function Shape() { + * this.x = 0; + * this.y = 0; + * } + * + * function Circle() { + * Shape.call(this); + * } + * + * Circle.prototype = _.create(Shape.prototype, { + * 'constructor': Circle + * }); + * + * var circle = new Circle; + * circle instanceof Circle; + * // => true + * + * circle instanceof Shape; + * // => true + */ + function create(prototype, properties) { + var result = baseCreate(prototype); + return properties == null ? result : baseAssign(result, properties); + } + + /** + * Assigns own and inherited enumerable string keyed properties of source + * objects to the destination object for all destination properties that + * resolve to `undefined`. Source objects are applied from left to right. + * Once a property is set, additional values of the same property are ignored. + * + * **Note:** This method mutates `object`. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category Object + * @param {Object} object The destination object. + * @param {...Object} [sources] The source objects. + * @returns {Object} Returns `object`. + * @see _.defaultsDeep + * @example + * + * _.defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 }); + * // => { 'a': 1, 'b': 2 } + */ + var defaults = baseRest(function(args) { + args.push(undefined, customDefaultsAssignIn); + return apply(assignInWith, undefined, args); + }); + + /** + * This method is like `_.defaults` except that it recursively assigns + * default properties. + * + * **Note:** This method mutates `object`. + * + * @static + * @memberOf _ + * @since 3.10.0 + * @category Object + * @param {Object} object The destination object. + * @param {...Object} [sources] The source objects. + * @returns {Object} Returns `object`. + * @see _.defaults + * @example + * + * _.defaultsDeep({ 'a': { 'b': 2 } }, { 'a': { 'b': 1, 'c': 3 } }); + * // => { 'a': { 'b': 2, 'c': 3 } } + */ + var defaultsDeep = baseRest(function(args) { + args.push(undefined, customDefaultsMerge); + return apply(mergeWith, undefined, args); + }); + + /** + * This method is like `_.find` except that it returns the key of the first + * element `predicate` returns truthy for instead of the element itself. + * + * @static + * @memberOf _ + * @since 1.1.0 + * @category Object + * @param {Object} object The object to inspect. + * @param {Function} [predicate=_.identity] The function invoked per iteration. + * @returns {string|undefined} Returns the key of the matched element, + * else `undefined`. + * @example + * + * var users = { + * 'barney': { 'age': 36, 'active': true }, + * 'fred': { 'age': 40, 'active': false }, + * 'pebbles': { 'age': 1, 'active': true } + * }; + * + * _.findKey(users, function(o) { return o.age < 40; }); + * // => 'barney' (iteration order is not guaranteed) + * + * // The `_.matches` iteratee shorthand. + * _.findKey(users, { 'age': 1, 'active': true }); + * // => 'pebbles' + * + * // The `_.matchesProperty` iteratee shorthand. + * _.findKey(users, ['active', false]); + * // => 'fred' + * + * // The `_.property` iteratee shorthand. + * _.findKey(users, 'active'); + * // => 'barney' + */ + function findKey(object, predicate) { + return baseFindKey(object, getIteratee(predicate, 3), baseForOwn); + } + + /** + * This method is like `_.findKey` except that it iterates over elements of + * a collection in the opposite order. + * + * @static + * @memberOf _ + * @since 2.0.0 + * @category Object + * @param {Object} object The object to inspect. + * @param {Function} [predicate=_.identity] The function invoked per iteration. + * @returns {string|undefined} Returns the key of the matched element, + * else `undefined`. + * @example + * + * var users = { + * 'barney': { 'age': 36, 'active': true }, + * 'fred': { 'age': 40, 'active': false }, + * 'pebbles': { 'age': 1, 'active': true } + * }; + * + * _.findLastKey(users, function(o) { return o.age < 40; }); + * // => returns 'pebbles' assuming `_.findKey` returns 'barney' + * + * // The `_.matches` iteratee shorthand. + * _.findLastKey(users, { 'age': 36, 'active': true }); + * // => 'barney' + * + * // The `_.matchesProperty` iteratee shorthand. + * _.findLastKey(users, ['active', false]); + * // => 'fred' + * + * // The `_.property` iteratee shorthand. + * _.findLastKey(users, 'active'); + * // => 'pebbles' + */ + function findLastKey(object, predicate) { + return baseFindKey(object, getIteratee(predicate, 3), baseForOwnRight); + } + + /** + * Iterates over own and inherited enumerable string keyed properties of an + * object and invokes `iteratee` for each property. The iteratee is invoked + * with three arguments: (value, key, object). Iteratee functions may exit + * iteration early by explicitly returning `false`. + * + * @static + * @memberOf _ + * @since 0.3.0 + * @category Object + * @param {Object} object The object to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @returns {Object} Returns `object`. + * @see _.forInRight + * @example + * + * function Foo() { + * this.a = 1; + * this.b = 2; + * } + * + * Foo.prototype.c = 3; + * + * _.forIn(new Foo, function(value, key) { + * console.log(key); + * }); + * // => Logs 'a', 'b', then 'c' (iteration order is not guaranteed). + */ + function forIn(object, iteratee) { + return object == null + ? object + : baseFor(object, getIteratee(iteratee, 3), keysIn); + } + + /** + * This method is like `_.forIn` except that it iterates over properties of + * `object` in the opposite order. + * + * @static + * @memberOf _ + * @since 2.0.0 + * @category Object + * @param {Object} object The object to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @returns {Object} Returns `object`. + * @see _.forIn + * @example + * + * function Foo() { + * this.a = 1; + * this.b = 2; + * } + * + * Foo.prototype.c = 3; + * + * _.forInRight(new Foo, function(value, key) { + * console.log(key); + * }); + * // => Logs 'c', 'b', then 'a' assuming `_.forIn` logs 'a', 'b', then 'c'. + */ + function forInRight(object, iteratee) { + return object == null + ? object + : baseForRight(object, getIteratee(iteratee, 3), keysIn); + } + + /** + * Iterates over own enumerable string keyed properties of an object and + * invokes `iteratee` for each property. The iteratee is invoked with three + * arguments: (value, key, object). Iteratee functions may exit iteration + * early by explicitly returning `false`. + * + * @static + * @memberOf _ + * @since 0.3.0 + * @category Object + * @param {Object} object The object to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @returns {Object} Returns `object`. + * @see _.forOwnRight + * @example + * + * function Foo() { + * this.a = 1; + * this.b = 2; + * } + * + * Foo.prototype.c = 3; + * + * _.forOwn(new Foo, function(value, key) { + * console.log(key); + * }); + * // => Logs 'a' then 'b' (iteration order is not guaranteed). + */ + function forOwn(object, iteratee) { + return object && baseForOwn(object, getIteratee(iteratee, 3)); + } + + /** + * This method is like `_.forOwn` except that it iterates over properties of + * `object` in the opposite order. + * + * @static + * @memberOf _ + * @since 2.0.0 + * @category Object + * @param {Object} object The object to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @returns {Object} Returns `object`. + * @see _.forOwn + * @example + * + * function Foo() { + * this.a = 1; + * this.b = 2; + * } + * + * Foo.prototype.c = 3; + * + * _.forOwnRight(new Foo, function(value, key) { + * console.log(key); + * }); + * // => Logs 'b' then 'a' assuming `_.forOwn` logs 'a' then 'b'. + */ + function forOwnRight(object, iteratee) { + return object && baseForOwnRight(object, getIteratee(iteratee, 3)); + } + + /** + * Creates an array of function property names from own enumerable properties + * of `object`. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category Object + * @param {Object} object The object to inspect. + * @returns {Array} Returns the function names. + * @see _.functionsIn + * @example + * + * function Foo() { + * this.a = _.constant('a'); + * this.b = _.constant('b'); + * } + * + * Foo.prototype.c = _.constant('c'); + * + * _.functions(new Foo); + * // => ['a', 'b'] + */ + function functions(object) { + return object == null ? [] : baseFunctions(object, keys(object)); + } + + /** + * Creates an array of function property names from own and inherited + * enumerable properties of `object`. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Object + * @param {Object} object The object to inspect. + * @returns {Array} Returns the function names. + * @see _.functions + * @example + * + * function Foo() { + * this.a = _.constant('a'); + * this.b = _.constant('b'); + * } + * + * Foo.prototype.c = _.constant('c'); + * + * _.functionsIn(new Foo); + * // => ['a', 'b', 'c'] + */ + function functionsIn(object) { + return object == null ? [] : baseFunctions(object, keysIn(object)); + } + + /** + * Gets the value at `path` of `object`. If the resolved value is + * `undefined`, the `defaultValue` is returned in its place. + * + * @static + * @memberOf _ + * @since 3.7.0 + * @category Object + * @param {Object} object The object to query. + * @param {Array|string} path The path of the property to get. + * @param {*} [defaultValue] The value returned for `undefined` resolved values. + * @returns {*} Returns the resolved value. + * @example + * + * var object = { 'a': [{ 'b': { 'c': 3 } }] }; + * + * _.get(object, 'a[0].b.c'); + * // => 3 + * + * _.get(object, ['a', '0', 'b', 'c']); + * // => 3 + * + * _.get(object, 'a.b.c', 'default'); + * // => 'default' + */ + function get(object, path, defaultValue) { + var result = object == null ? undefined : baseGet(object, path); + return result === undefined ? defaultValue : result; + } + + /** + * Checks if `path` is a direct property of `object`. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category Object + * @param {Object} object The object to query. + * @param {Array|string} path The path to check. + * @returns {boolean} Returns `true` if `path` exists, else `false`. + * @example + * + * var object = { 'a': { 'b': 2 } }; + * var other = _.create({ 'a': _.create({ 'b': 2 }) }); + * + * _.has(object, 'a'); + * // => true + * + * _.has(object, 'a.b'); + * // => true + * + * _.has(object, ['a', 'b']); + * // => true + * + * _.has(other, 'a'); + * // => false + */ + function has(object, path) { + return object != null && hasPath(object, path, baseHas); + } + + /** + * Checks if `path` is a direct or inherited property of `object`. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Object + * @param {Object} object The object to query. + * @param {Array|string} path The path to check. + * @returns {boolean} Returns `true` if `path` exists, else `false`. + * @example + * + * var object = _.create({ 'a': _.create({ 'b': 2 }) }); + * + * _.hasIn(object, 'a'); + * // => true + * + * _.hasIn(object, 'a.b'); + * // => true + * + * _.hasIn(object, ['a', 'b']); + * // => true + * + * _.hasIn(object, 'b'); + * // => false + */ + function hasIn(object, path) { + return object != null && hasPath(object, path, baseHasIn); + } + + /** + * Creates an object composed of the inverted keys and values of `object`. + * If `object` contains duplicate values, subsequent values overwrite + * property assignments of previous values. + * + * @static + * @memberOf _ + * @since 0.7.0 + * @category Object + * @param {Object} object The object to invert. + * @returns {Object} Returns the new inverted object. + * @example + * + * var object = { 'a': 1, 'b': 2, 'c': 1 }; + * + * _.invert(object); + * // => { '1': 'c', '2': 'b' } + */ + var invert = createInverter(function(result, value, key) { + result[value] = key; + }, constant(identity)); + + /** + * This method is like `_.invert` except that the inverted object is generated + * from the results of running each element of `object` thru `iteratee`. The + * corresponding inverted value of each inverted key is an array of keys + * responsible for generating the inverted value. The iteratee is invoked + * with one argument: (value). + * + * @static + * @memberOf _ + * @since 4.1.0 + * @category Object + * @param {Object} object The object to invert. + * @param {Function} [iteratee=_.identity] The iteratee invoked per element. + * @returns {Object} Returns the new inverted object. + * @example + * + * var object = { 'a': 1, 'b': 2, 'c': 1 }; + * + * _.invertBy(object); + * // => { '1': ['a', 'c'], '2': ['b'] } + * + * _.invertBy(object, function(value) { + * return 'group' + value; + * }); + * // => { 'group1': ['a', 'c'], 'group2': ['b'] } + */ + var invertBy = createInverter(function(result, value, key) { + if (hasOwnProperty.call(result, value)) { + result[value].push(key); + } else { + result[value] = [key]; + } + }, getIteratee); + + /** + * Invokes the method at `path` of `object`. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Object + * @param {Object} object The object to query. + * @param {Array|string} path The path of the method to invoke. + * @param {...*} [args] The arguments to invoke the method with. + * @returns {*} Returns the result of the invoked method. + * @example + * + * var object = { 'a': [{ 'b': { 'c': [1, 2, 3, 4] } }] }; + * + * _.invoke(object, 'a[0].b.c.slice', 1, 3); + * // => [2, 3] + */ + var invoke = baseRest(baseInvoke); + + /** + * Creates an array of the own enumerable property names of `object`. + * + * **Note:** Non-object values are coerced to objects. See the + * [ES spec](http://ecma-international.org/ecma-262/7.0/#sec-object.keys) + * for more details. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category Object + * @param {Object} object The object to query. + * @returns {Array} Returns the array of property names. + * @example + * + * function Foo() { + * this.a = 1; + * this.b = 2; + * } + * + * Foo.prototype.c = 3; + * + * _.keys(new Foo); + * // => ['a', 'b'] (iteration order is not guaranteed) + * + * _.keys('hi'); + * // => ['0', '1'] + */ + function keys(object) { + return isArrayLike(object) ? arrayLikeKeys(object) : baseKeys(object); + } + + /** + * Creates an array of the own and inherited enumerable property names of `object`. + * + * **Note:** Non-object values are coerced to objects. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Object + * @param {Object} object The object to query. + * @returns {Array} Returns the array of property names. + * @example + * + * function Foo() { + * this.a = 1; + * this.b = 2; + * } + * + * Foo.prototype.c = 3; + * + * _.keysIn(new Foo); + * // => ['a', 'b', 'c'] (iteration order is not guaranteed) + */ + function keysIn(object) { + return isArrayLike(object) ? arrayLikeKeys(object, true) : baseKeysIn(object); + } + + /** + * The opposite of `_.mapValues`; this method creates an object with the + * same values as `object` and keys generated by running each own enumerable + * string keyed property of `object` thru `iteratee`. The iteratee is invoked + * with three arguments: (value, key, object). + * + * @static + * @memberOf _ + * @since 3.8.0 + * @category Object + * @param {Object} object The object to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @returns {Object} Returns the new mapped object. + * @see _.mapValues + * @example + * + * _.mapKeys({ 'a': 1, 'b': 2 }, function(value, key) { + * return key + value; + * }); + * // => { 'a1': 1, 'b2': 2 } + */ + function mapKeys(object, iteratee) { + var result = {}; + iteratee = getIteratee(iteratee, 3); + + baseForOwn(object, function(value, key, object) { + baseAssignValue(result, iteratee(value, key, object), value); + }); + return result; + } + + /** + * Creates an object with the same keys as `object` and values generated + * by running each own enumerable string keyed property of `object` thru + * `iteratee`. The iteratee is invoked with three arguments: + * (value, key, object). + * + * @static + * @memberOf _ + * @since 2.4.0 + * @category Object + * @param {Object} object The object to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @returns {Object} Returns the new mapped object. + * @see _.mapKeys + * @example + * + * var users = { + * 'fred': { 'user': 'fred', 'age': 40 }, + * 'pebbles': { 'user': 'pebbles', 'age': 1 } + * }; + * + * _.mapValues(users, function(o) { return o.age; }); + * // => { 'fred': 40, 'pebbles': 1 } (iteration order is not guaranteed) + * + * // The `_.property` iteratee shorthand. + * _.mapValues(users, 'age'); + * // => { 'fred': 40, 'pebbles': 1 } (iteration order is not guaranteed) + */ + function mapValues(object, iteratee) { + var result = {}; + iteratee = getIteratee(iteratee, 3); + + baseForOwn(object, function(value, key, object) { + baseAssignValue(result, key, iteratee(value, key, object)); + }); + return result; + } + + /** + * This method is like `_.assign` except that it recursively merges own and + * inherited enumerable string keyed properties of source objects into the + * destination object. Source properties that resolve to `undefined` are + * skipped if a destination value exists. Array and plain object properties + * are merged recursively. Other objects and value types are overridden by + * assignment. Source objects are applied from left to right. Subsequent + * sources overwrite property assignments of previous sources. + * + * **Note:** This method mutates `object`. + * + * @static + * @memberOf _ + * @since 0.5.0 + * @category Object + * @param {Object} object The destination object. + * @param {...Object} [sources] The source objects. + * @returns {Object} Returns `object`. + * @example + * + * var object = { + * 'a': [{ 'b': 2 }, { 'd': 4 }] + * }; + * + * var other = { + * 'a': [{ 'c': 3 }, { 'e': 5 }] + * }; + * + * _.merge(object, other); + * // => { 'a': [{ 'b': 2, 'c': 3 }, { 'd': 4, 'e': 5 }] } + */ + var merge = createAssigner(function(object, source, srcIndex) { + baseMerge(object, source, srcIndex); + }); + + /** + * This method is like `_.merge` except that it accepts `customizer` which + * is invoked to produce the merged values of the destination and source + * properties. If `customizer` returns `undefined`, merging is handled by the + * method instead. The `customizer` is invoked with six arguments: + * (objValue, srcValue, key, object, source, stack). + * + * **Note:** This method mutates `object`. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Object + * @param {Object} object The destination object. + * @param {...Object} sources The source objects. + * @param {Function} customizer The function to customize assigned values. + * @returns {Object} Returns `object`. + * @example + * + * function customizer(objValue, srcValue) { + * if (_.isArray(objValue)) { + * return objValue.concat(srcValue); + * } + * } + * + * var object = { 'a': [1], 'b': [2] }; + * var other = { 'a': [3], 'b': [4] }; + * + * _.mergeWith(object, other, customizer); + * // => { 'a': [1, 3], 'b': [2, 4] } + */ + var mergeWith = createAssigner(function(object, source, srcIndex, customizer) { + baseMerge(object, source, srcIndex, customizer); + }); + + /** + * The opposite of `_.pick`; this method creates an object composed of the + * own and inherited enumerable property paths of `object` that are not omitted. + * + * **Note:** This method is considerably slower than `_.pick`. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category Object + * @param {Object} object The source object. + * @param {...(string|string[])} [paths] The property paths to omit. + * @returns {Object} Returns the new object. + * @example + * + * var object = { 'a': 1, 'b': '2', 'c': 3 }; + * + * _.omit(object, ['a', 'c']); + * // => { 'b': '2' } + */ + var omit = flatRest(function(object, paths) { + var result = {}; + if (object == null) { + return result; + } + var isDeep = false; + paths = arrayMap(paths, function(path) { + path = castPath(path, object); + isDeep || (isDeep = path.length > 1); + return path; + }); + copyObject(object, getAllKeysIn(object), result); + if (isDeep) { + result = baseClone(result, CLONE_DEEP_FLAG | CLONE_FLAT_FLAG | CLONE_SYMBOLS_FLAG, customOmitClone); + } + var length = paths.length; + while (length--) { + baseUnset(result, paths[length]); + } + return result; + }); + + /** + * The opposite of `_.pickBy`; this method creates an object composed of + * the own and inherited enumerable string keyed properties of `object` that + * `predicate` doesn't return truthy for. The predicate is invoked with two + * arguments: (value, key). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Object + * @param {Object} object The source object. + * @param {Function} [predicate=_.identity] The function invoked per property. + * @returns {Object} Returns the new object. + * @example + * + * var object = { 'a': 1, 'b': '2', 'c': 3 }; + * + * _.omitBy(object, _.isNumber); + * // => { 'b': '2' } + */ + function omitBy(object, predicate) { + return pickBy(object, negate(getIteratee(predicate))); + } + + /** + * Creates an object composed of the picked `object` properties. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category Object + * @param {Object} object The source object. + * @param {...(string|string[])} [paths] The property paths to pick. + * @returns {Object} Returns the new object. + * @example + * + * var object = { 'a': 1, 'b': '2', 'c': 3 }; + * + * _.pick(object, ['a', 'c']); + * // => { 'a': 1, 'c': 3 } + */ + var pick = flatRest(function(object, paths) { + return object == null ? {} : basePick(object, paths); + }); + + /** + * Creates an object composed of the `object` properties `predicate` returns + * truthy for. The predicate is invoked with two arguments: (value, key). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Object + * @param {Object} object The source object. + * @param {Function} [predicate=_.identity] The function invoked per property. + * @returns {Object} Returns the new object. + * @example + * + * var object = { 'a': 1, 'b': '2', 'c': 3 }; + * + * _.pickBy(object, _.isNumber); + * // => { 'a': 1, 'c': 3 } + */ + function pickBy(object, predicate) { + if (object == null) { + return {}; + } + var props = arrayMap(getAllKeysIn(object), function(prop) { + return [prop]; + }); + predicate = getIteratee(predicate); + return basePickBy(object, props, function(value, path) { + return predicate(value, path[0]); + }); + } + + /** + * This method is like `_.get` except that if the resolved value is a + * function it's invoked with the `this` binding of its parent object and + * its result is returned. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category Object + * @param {Object} object The object to query. + * @param {Array|string} path The path of the property to resolve. + * @param {*} [defaultValue] The value returned for `undefined` resolved values. + * @returns {*} Returns the resolved value. + * @example + * + * var object = { 'a': [{ 'b': { 'c1': 3, 'c2': _.constant(4) } }] }; + * + * _.result(object, 'a[0].b.c1'); + * // => 3 + * + * _.result(object, 'a[0].b.c2'); + * // => 4 + * + * _.result(object, 'a[0].b.c3', 'default'); + * // => 'default' + * + * _.result(object, 'a[0].b.c3', _.constant('default')); + * // => 'default' + */ + function result(object, path, defaultValue) { + path = castPath(path, object); + + var index = -1, + length = path.length; + + // Ensure the loop is entered when path is empty. + if (!length) { + length = 1; + object = undefined; + } + while (++index < length) { + var value = object == null ? undefined : object[toKey(path[index])]; + if (value === undefined) { + index = length; + value = defaultValue; + } + object = isFunction(value) ? value.call(object) : value; + } + return object; + } + + /** + * Sets the value at `path` of `object`. If a portion of `path` doesn't exist, + * it's created. Arrays are created for missing index properties while objects + * are created for all other missing properties. Use `_.setWith` to customize + * `path` creation. + * + * **Note:** This method mutates `object`. + * + * @static + * @memberOf _ + * @since 3.7.0 + * @category Object + * @param {Object} object The object to modify. + * @param {Array|string} path The path of the property to set. + * @param {*} value The value to set. + * @returns {Object} Returns `object`. + * @example + * + * var object = { 'a': [{ 'b': { 'c': 3 } }] }; + * + * _.set(object, 'a[0].b.c', 4); + * console.log(object.a[0].b.c); + * // => 4 + * + * _.set(object, ['x', '0', 'y', 'z'], 5); + * console.log(object.x[0].y.z); + * // => 5 + */ + function set(object, path, value) { + return object == null ? object : baseSet(object, path, value); + } + + /** + * This method is like `_.set` except that it accepts `customizer` which is + * invoked to produce the objects of `path`. If `customizer` returns `undefined` + * path creation is handled by the method instead. The `customizer` is invoked + * with three arguments: (nsValue, key, nsObject). + * + * **Note:** This method mutates `object`. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Object + * @param {Object} object The object to modify. + * @param {Array|string} path The path of the property to set. + * @param {*} value The value to set. + * @param {Function} [customizer] The function to customize assigned values. + * @returns {Object} Returns `object`. + * @example + * + * var object = {}; + * + * _.setWith(object, '[0][1]', 'a', Object); + * // => { '0': { '1': 'a' } } + */ + function setWith(object, path, value, customizer) { + customizer = typeof customizer == 'function' ? customizer : undefined; + return object == null ? object : baseSet(object, path, value, customizer); + } + + /** + * Creates an array of own enumerable string keyed-value pairs for `object` + * which can be consumed by `_.fromPairs`. If `object` is a map or set, its + * entries are returned. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @alias entries + * @category Object + * @param {Object} object The object to query. + * @returns {Array} Returns the key-value pairs. + * @example + * + * function Foo() { + * this.a = 1; + * this.b = 2; + * } + * + * Foo.prototype.c = 3; + * + * _.toPairs(new Foo); + * // => [['a', 1], ['b', 2]] (iteration order is not guaranteed) + */ + var toPairs = createToPairs(keys); + + /** + * Creates an array of own and inherited enumerable string keyed-value pairs + * for `object` which can be consumed by `_.fromPairs`. If `object` is a map + * or set, its entries are returned. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @alias entriesIn + * @category Object + * @param {Object} object The object to query. + * @returns {Array} Returns the key-value pairs. + * @example + * + * function Foo() { + * this.a = 1; + * this.b = 2; + * } + * + * Foo.prototype.c = 3; + * + * _.toPairsIn(new Foo); + * // => [['a', 1], ['b', 2], ['c', 3]] (iteration order is not guaranteed) + */ + var toPairsIn = createToPairs(keysIn); + + /** + * An alternative to `_.reduce`; this method transforms `object` to a new + * `accumulator` object which is the result of running each of its own + * enumerable string keyed properties thru `iteratee`, with each invocation + * potentially mutating the `accumulator` object. If `accumulator` is not + * provided, a new object with the same `[[Prototype]]` will be used. The + * iteratee is invoked with four arguments: (accumulator, value, key, object). + * Iteratee functions may exit iteration early by explicitly returning `false`. + * + * @static + * @memberOf _ + * @since 1.3.0 + * @category Object + * @param {Object} object The object to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @param {*} [accumulator] The custom accumulator value. + * @returns {*} Returns the accumulated value. + * @example + * + * _.transform([2, 3, 4], function(result, n) { + * result.push(n *= n); + * return n % 2 == 0; + * }, []); + * // => [4, 9] + * + * _.transform({ 'a': 1, 'b': 2, 'c': 1 }, function(result, value, key) { + * (result[value] || (result[value] = [])).push(key); + * }, {}); + * // => { '1': ['a', 'c'], '2': ['b'] } + */ + function transform(object, iteratee, accumulator) { + var isArr = isArray(object), + isArrLike = isArr || isBuffer(object) || isTypedArray(object); + + iteratee = getIteratee(iteratee, 4); + if (accumulator == null) { + var Ctor = object && object.constructor; + if (isArrLike) { + accumulator = isArr ? new Ctor : []; + } + else if (isObject(object)) { + accumulator = isFunction(Ctor) ? baseCreate(getPrototype(object)) : {}; + } + else { + accumulator = {}; + } + } + (isArrLike ? arrayEach : baseForOwn)(object, function(value, index, object) { + return iteratee(accumulator, value, index, object); + }); + return accumulator; + } + + /** + * Removes the property at `path` of `object`. + * + * **Note:** This method mutates `object`. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Object + * @param {Object} object The object to modify. + * @param {Array|string} path The path of the property to unset. + * @returns {boolean} Returns `true` if the property is deleted, else `false`. + * @example + * + * var object = { 'a': [{ 'b': { 'c': 7 } }] }; + * _.unset(object, 'a[0].b.c'); + * // => true + * + * console.log(object); + * // => { 'a': [{ 'b': {} }] }; + * + * _.unset(object, ['a', '0', 'b', 'c']); + * // => true + * + * console.log(object); + * // => { 'a': [{ 'b': {} }] }; + */ + function unset(object, path) { + return object == null ? true : baseUnset(object, path); + } + + /** + * This method is like `_.set` except that accepts `updater` to produce the + * value to set. Use `_.updateWith` to customize `path` creation. The `updater` + * is invoked with one argument: (value). + * + * **Note:** This method mutates `object`. + * + * @static + * @memberOf _ + * @since 4.6.0 + * @category Object + * @param {Object} object The object to modify. + * @param {Array|string} path The path of the property to set. + * @param {Function} updater The function to produce the updated value. + * @returns {Object} Returns `object`. + * @example + * + * var object = { 'a': [{ 'b': { 'c': 3 } }] }; + * + * _.update(object, 'a[0].b.c', function(n) { return n * n; }); + * console.log(object.a[0].b.c); + * // => 9 + * + * _.update(object, 'x[0].y.z', function(n) { return n ? n + 1 : 0; }); + * console.log(object.x[0].y.z); + * // => 0 + */ + function update(object, path, updater) { + return object == null ? object : baseUpdate(object, path, castFunction(updater)); + } + + /** + * This method is like `_.update` except that it accepts `customizer` which is + * invoked to produce the objects of `path`. If `customizer` returns `undefined` + * path creation is handled by the method instead. The `customizer` is invoked + * with three arguments: (nsValue, key, nsObject). + * + * **Note:** This method mutates `object`. + * + * @static + * @memberOf _ + * @since 4.6.0 + * @category Object + * @param {Object} object The object to modify. + * @param {Array|string} path The path of the property to set. + * @param {Function} updater The function to produce the updated value. + * @param {Function} [customizer] The function to customize assigned values. + * @returns {Object} Returns `object`. + * @example + * + * var object = {}; + * + * _.updateWith(object, '[0][1]', _.constant('a'), Object); + * // => { '0': { '1': 'a' } } + */ + function updateWith(object, path, updater, customizer) { + customizer = typeof customizer == 'function' ? customizer : undefined; + return object == null ? object : baseUpdate(object, path, castFunction(updater), customizer); + } + + /** + * Creates an array of the own enumerable string keyed property values of `object`. + * + * **Note:** Non-object values are coerced to objects. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category Object + * @param {Object} object The object to query. + * @returns {Array} Returns the array of property values. + * @example + * + * function Foo() { + * this.a = 1; + * this.b = 2; + * } + * + * Foo.prototype.c = 3; + * + * _.values(new Foo); + * // => [1, 2] (iteration order is not guaranteed) + * + * _.values('hi'); + * // => ['h', 'i'] + */ + function values(object) { + return object == null ? [] : baseValues(object, keys(object)); + } + + /** + * Creates an array of the own and inherited enumerable string keyed property + * values of `object`. + * + * **Note:** Non-object values are coerced to objects. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Object + * @param {Object} object The object to query. + * @returns {Array} Returns the array of property values. + * @example + * + * function Foo() { + * this.a = 1; + * this.b = 2; + * } + * + * Foo.prototype.c = 3; + * + * _.valuesIn(new Foo); + * // => [1, 2, 3] (iteration order is not guaranteed) + */ + function valuesIn(object) { + return object == null ? [] : baseValues(object, keysIn(object)); + } + + /*------------------------------------------------------------------------*/ + + /** + * Clamps `number` within the inclusive `lower` and `upper` bounds. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Number + * @param {number} number The number to clamp. + * @param {number} [lower] The lower bound. + * @param {number} upper The upper bound. + * @returns {number} Returns the clamped number. + * @example + * + * _.clamp(-10, -5, 5); + * // => -5 + * + * _.clamp(10, -5, 5); + * // => 5 + */ + function clamp(number, lower, upper) { + if (upper === undefined) { + upper = lower; + lower = undefined; + } + if (upper !== undefined) { + upper = toNumber(upper); + upper = upper === upper ? upper : 0; + } + if (lower !== undefined) { + lower = toNumber(lower); + lower = lower === lower ? lower : 0; + } + return baseClamp(toNumber(number), lower, upper); + } + + /** + * Checks if `n` is between `start` and up to, but not including, `end`. If + * `end` is not specified, it's set to `start` with `start` then set to `0`. + * If `start` is greater than `end` the params are swapped to support + * negative ranges. + * + * @static + * @memberOf _ + * @since 3.3.0 + * @category Number + * @param {number} number The number to check. + * @param {number} [start=0] The start of the range. + * @param {number} end The end of the range. + * @returns {boolean} Returns `true` if `number` is in the range, else `false`. + * @see _.range, _.rangeRight + * @example + * + * _.inRange(3, 2, 4); + * // => true + * + * _.inRange(4, 8); + * // => true + * + * _.inRange(4, 2); + * // => false + * + * _.inRange(2, 2); + * // => false + * + * _.inRange(1.2, 2); + * // => true + * + * _.inRange(5.2, 4); + * // => false + * + * _.inRange(-3, -2, -6); + * // => true + */ + function inRange(number, start, end) { + start = toFinite(start); + if (end === undefined) { + end = start; + start = 0; + } else { + end = toFinite(end); + } + number = toNumber(number); + return baseInRange(number, start, end); + } + + /** + * Produces a random number between the inclusive `lower` and `upper` bounds. + * If only one argument is provided a number between `0` and the given number + * is returned. If `floating` is `true`, or either `lower` or `upper` are + * floats, a floating-point number is returned instead of an integer. + * + * **Note:** JavaScript follows the IEEE-754 standard for resolving + * floating-point values which can produce unexpected results. + * + * @static + * @memberOf _ + * @since 0.7.0 + * @category Number + * @param {number} [lower=0] The lower bound. + * @param {number} [upper=1] The upper bound. + * @param {boolean} [floating] Specify returning a floating-point number. + * @returns {number} Returns the random number. + * @example + * + * _.random(0, 5); + * // => an integer between 0 and 5 + * + * _.random(5); + * // => also an integer between 0 and 5 + * + * _.random(5, true); + * // => a floating-point number between 0 and 5 + * + * _.random(1.2, 5.2); + * // => a floating-point number between 1.2 and 5.2 + */ + function random(lower, upper, floating) { + if (floating && typeof floating != 'boolean' && isIterateeCall(lower, upper, floating)) { + upper = floating = undefined; + } + if (floating === undefined) { + if (typeof upper == 'boolean') { + floating = upper; + upper = undefined; + } + else if (typeof lower == 'boolean') { + floating = lower; + lower = undefined; + } + } + if (lower === undefined && upper === undefined) { + lower = 0; + upper = 1; + } + else { + lower = toFinite(lower); + if (upper === undefined) { + upper = lower; + lower = 0; + } else { + upper = toFinite(upper); + } + } + if (lower > upper) { + var temp = lower; + lower = upper; + upper = temp; + } + if (floating || lower % 1 || upper % 1) { + var rand = nativeRandom(); + return nativeMin(lower + (rand * (upper - lower + freeParseFloat('1e-' + ((rand + '').length - 1)))), upper); + } + return baseRandom(lower, upper); + } + + /*------------------------------------------------------------------------*/ + + /** + * Converts `string` to [camel case](https://en.wikipedia.org/wiki/CamelCase). + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category String + * @param {string} [string=''] The string to convert. + * @returns {string} Returns the camel cased string. + * @example + * + * _.camelCase('Foo Bar'); + * // => 'fooBar' + * + * _.camelCase('--foo-bar--'); + * // => 'fooBar' + * + * _.camelCase('__FOO_BAR__'); + * // => 'fooBar' + */ + var camelCase = createCompounder(function(result, word, index) { + word = word.toLowerCase(); + return result + (index ? capitalize(word) : word); + }); + + /** + * Converts the first character of `string` to upper case and the remaining + * to lower case. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category String + * @param {string} [string=''] The string to capitalize. + * @returns {string} Returns the capitalized string. + * @example + * + * _.capitalize('FRED'); + * // => 'Fred' + */ + function capitalize(string) { + return upperFirst(toString(string).toLowerCase()); + } + + /** + * Deburrs `string` by converting + * [Latin-1 Supplement](https://en.wikipedia.org/wiki/Latin-1_Supplement_(Unicode_block)#Character_table) + * and [Latin Extended-A](https://en.wikipedia.org/wiki/Latin_Extended-A) + * letters to basic Latin letters and removing + * [combining diacritical marks](https://en.wikipedia.org/wiki/Combining_Diacritical_Marks). + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category String + * @param {string} [string=''] The string to deburr. + * @returns {string} Returns the deburred string. + * @example + * + * _.deburr('déjà vu'); + * // => 'deja vu' + */ + function deburr(string) { + string = toString(string); + return string && string.replace(reLatin, deburrLetter).replace(reComboMark, ''); + } + + /** + * Checks if `string` ends with the given target string. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category String + * @param {string} [string=''] The string to inspect. + * @param {string} [target] The string to search for. + * @param {number} [position=string.length] The position to search up to. + * @returns {boolean} Returns `true` if `string` ends with `target`, + * else `false`. + * @example + * + * _.endsWith('abc', 'c'); + * // => true + * + * _.endsWith('abc', 'b'); + * // => false + * + * _.endsWith('abc', 'b', 2); + * // => true + */ + function endsWith(string, target, position) { + string = toString(string); + target = baseToString(target); + + var length = string.length; + position = position === undefined + ? length + : baseClamp(toInteger(position), 0, length); + + var end = position; + position -= target.length; + return position >= 0 && string.slice(position, end) == target; + } + + /** + * Converts the characters "&", "<", ">", '"', and "'" in `string` to their + * corresponding HTML entities. + * + * **Note:** No other characters are escaped. To escape additional + * characters use a third-party library like [_he_](https://mths.be/he). + * + * Though the ">" character is escaped for symmetry, characters like + * ">" and "/" don't need escaping in HTML and have no special meaning + * unless they're part of a tag or unquoted attribute value. See + * [Mathias Bynens's article](https://mathiasbynens.be/notes/ambiguous-ampersands) + * (under "semi-related fun fact") for more details. + * + * When working with HTML you should always + * [quote attribute values](http://wonko.com/post/html-escaping) to reduce + * XSS vectors. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category String + * @param {string} [string=''] The string to escape. + * @returns {string} Returns the escaped string. + * @example + * + * _.escape('fred, barney, & pebbles'); + * // => 'fred, barney, & pebbles' + */ + function escape(string) { + string = toString(string); + return (string && reHasUnescapedHtml.test(string)) + ? string.replace(reUnescapedHtml, escapeHtmlChar) + : string; + } + + /** + * Escapes the `RegExp` special characters "^", "$", "\", ".", "*", "+", + * "?", "(", ")", "[", "]", "{", "}", and "|" in `string`. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category String + * @param {string} [string=''] The string to escape. + * @returns {string} Returns the escaped string. + * @example + * + * _.escapeRegExp('[lodash](https://lodash.com/)'); + * // => '\[lodash\]\(https://lodash\.com/\)' + */ + function escapeRegExp(string) { + string = toString(string); + return (string && reHasRegExpChar.test(string)) + ? string.replace(reRegExpChar, '\\$&') + : string; + } + + /** + * Converts `string` to + * [kebab case](https://en.wikipedia.org/wiki/Letter_case#Special_case_styles). + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category String + * @param {string} [string=''] The string to convert. + * @returns {string} Returns the kebab cased string. + * @example + * + * _.kebabCase('Foo Bar'); + * // => 'foo-bar' + * + * _.kebabCase('fooBar'); + * // => 'foo-bar' + * + * _.kebabCase('__FOO_BAR__'); + * // => 'foo-bar' + */ + var kebabCase = createCompounder(function(result, word, index) { + return result + (index ? '-' : '') + word.toLowerCase(); + }); + + /** + * Converts `string`, as space separated words, to lower case. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category String + * @param {string} [string=''] The string to convert. + * @returns {string} Returns the lower cased string. + * @example + * + * _.lowerCase('--Foo-Bar--'); + * // => 'foo bar' + * + * _.lowerCase('fooBar'); + * // => 'foo bar' + * + * _.lowerCase('__FOO_BAR__'); + * // => 'foo bar' + */ + var lowerCase = createCompounder(function(result, word, index) { + return result + (index ? ' ' : '') + word.toLowerCase(); + }); + + /** + * Converts the first character of `string` to lower case. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category String + * @param {string} [string=''] The string to convert. + * @returns {string} Returns the converted string. + * @example + * + * _.lowerFirst('Fred'); + * // => 'fred' + * + * _.lowerFirst('FRED'); + * // => 'fRED' + */ + var lowerFirst = createCaseFirst('toLowerCase'); + + /** + * Pads `string` on the left and right sides if it's shorter than `length`. + * Padding characters are truncated if they can't be evenly divided by `length`. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category String + * @param {string} [string=''] The string to pad. + * @param {number} [length=0] The padding length. + * @param {string} [chars=' '] The string used as padding. + * @returns {string} Returns the padded string. + * @example + * + * _.pad('abc', 8); + * // => ' abc ' + * + * _.pad('abc', 8, '_-'); + * // => '_-abc_-_' + * + * _.pad('abc', 3); + * // => 'abc' + */ + function pad(string, length, chars) { + string = toString(string); + length = toInteger(length); + + var strLength = length ? stringSize(string) : 0; + if (!length || strLength >= length) { + return string; + } + var mid = (length - strLength) / 2; + return ( + createPadding(nativeFloor(mid), chars) + + string + + createPadding(nativeCeil(mid), chars) + ); + } + + /** + * Pads `string` on the right side if it's shorter than `length`. Padding + * characters are truncated if they exceed `length`. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category String + * @param {string} [string=''] The string to pad. + * @param {number} [length=0] The padding length. + * @param {string} [chars=' '] The string used as padding. + * @returns {string} Returns the padded string. + * @example + * + * _.padEnd('abc', 6); + * // => 'abc ' + * + * _.padEnd('abc', 6, '_-'); + * // => 'abc_-_' + * + * _.padEnd('abc', 3); + * // => 'abc' + */ + function padEnd(string, length, chars) { + string = toString(string); + length = toInteger(length); + + var strLength = length ? stringSize(string) : 0; + return (length && strLength < length) + ? (string + createPadding(length - strLength, chars)) + : string; + } + + /** + * Pads `string` on the left side if it's shorter than `length`. Padding + * characters are truncated if they exceed `length`. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category String + * @param {string} [string=''] The string to pad. + * @param {number} [length=0] The padding length. + * @param {string} [chars=' '] The string used as padding. + * @returns {string} Returns the padded string. + * @example + * + * _.padStart('abc', 6); + * // => ' abc' + * + * _.padStart('abc', 6, '_-'); + * // => '_-_abc' + * + * _.padStart('abc', 3); + * // => 'abc' + */ + function padStart(string, length, chars) { + string = toString(string); + length = toInteger(length); + + var strLength = length ? stringSize(string) : 0; + return (length && strLength < length) + ? (createPadding(length - strLength, chars) + string) + : string; + } + + /** + * Converts `string` to an integer of the specified radix. If `radix` is + * `undefined` or `0`, a `radix` of `10` is used unless `value` is a + * hexadecimal, in which case a `radix` of `16` is used. + * + * **Note:** This method aligns with the + * [ES5 implementation](https://es5.github.io/#x15.1.2.2) of `parseInt`. + * + * @static + * @memberOf _ + * @since 1.1.0 + * @category String + * @param {string} string The string to convert. + * @param {number} [radix=10] The radix to interpret `value` by. + * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`. + * @returns {number} Returns the converted integer. + * @example + * + * _.parseInt('08'); + * // => 8 + * + * _.map(['6', '08', '10'], _.parseInt); + * // => [6, 8, 10] + */ + function parseInt(string, radix, guard) { + if (guard || radix == null) { + radix = 0; + } else if (radix) { + radix = +radix; + } + return nativeParseInt(toString(string).replace(reTrimStart, ''), radix || 0); + } + + /** + * Repeats the given string `n` times. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category String + * @param {string} [string=''] The string to repeat. + * @param {number} [n=1] The number of times to repeat the string. + * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`. + * @returns {string} Returns the repeated string. + * @example + * + * _.repeat('*', 3); + * // => '***' + * + * _.repeat('abc', 2); + * // => 'abcabc' + * + * _.repeat('abc', 0); + * // => '' + */ + function repeat(string, n, guard) { + if ((guard ? isIterateeCall(string, n, guard) : n === undefined)) { + n = 1; + } else { + n = toInteger(n); + } + return baseRepeat(toString(string), n); + } + + /** + * Replaces matches for `pattern` in `string` with `replacement`. + * + * **Note:** This method is based on + * [`String#replace`](https://mdn.io/String/replace). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category String + * @param {string} [string=''] The string to modify. + * @param {RegExp|string} pattern The pattern to replace. + * @param {Function|string} replacement The match replacement. + * @returns {string} Returns the modified string. + * @example + * + * _.replace('Hi Fred', 'Fred', 'Barney'); + * // => 'Hi Barney' + */ + function replace() { + var args = arguments, + string = toString(args[0]); + + return args.length < 3 ? string : string.replace(args[1], args[2]); + } + + /** + * Converts `string` to + * [snake case](https://en.wikipedia.org/wiki/Snake_case). + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category String + * @param {string} [string=''] The string to convert. + * @returns {string} Returns the snake cased string. + * @example + * + * _.snakeCase('Foo Bar'); + * // => 'foo_bar' + * + * _.snakeCase('fooBar'); + * // => 'foo_bar' + * + * _.snakeCase('--FOO-BAR--'); + * // => 'foo_bar' + */ + var snakeCase = createCompounder(function(result, word, index) { + return result + (index ? '_' : '') + word.toLowerCase(); + }); + + /** + * Splits `string` by `separator`. + * + * **Note:** This method is based on + * [`String#split`](https://mdn.io/String/split). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category String + * @param {string} [string=''] The string to split. + * @param {RegExp|string} separator The separator pattern to split by. + * @param {number} [limit] The length to truncate results to. + * @returns {Array} Returns the string segments. + * @example + * + * _.split('a-b-c', '-', 2); + * // => ['a', 'b'] + */ + function split(string, separator, limit) { + if (limit && typeof limit != 'number' && isIterateeCall(string, separator, limit)) { + separator = limit = undefined; + } + limit = limit === undefined ? MAX_ARRAY_LENGTH : limit >>> 0; + if (!limit) { + return []; + } + string = toString(string); + if (string && ( + typeof separator == 'string' || + (separator != null && !isRegExp(separator)) + )) { + separator = baseToString(separator); + if (!separator && hasUnicode(string)) { + return castSlice(stringToArray(string), 0, limit); + } + } + return string.split(separator, limit); + } + + /** + * Converts `string` to + * [start case](https://en.wikipedia.org/wiki/Letter_case#Stylistic_or_specialised_usage). + * + * @static + * @memberOf _ + * @since 3.1.0 + * @category String + * @param {string} [string=''] The string to convert. + * @returns {string} Returns the start cased string. + * @example + * + * _.startCase('--foo-bar--'); + * // => 'Foo Bar' + * + * _.startCase('fooBar'); + * // => 'Foo Bar' + * + * _.startCase('__FOO_BAR__'); + * // => 'FOO BAR' + */ + var startCase = createCompounder(function(result, word, index) { + return result + (index ? ' ' : '') + upperFirst(word); + }); + + /** + * Checks if `string` starts with the given target string. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category String + * @param {string} [string=''] The string to inspect. + * @param {string} [target] The string to search for. + * @param {number} [position=0] The position to search from. + * @returns {boolean} Returns `true` if `string` starts with `target`, + * else `false`. + * @example + * + * _.startsWith('abc', 'a'); + * // => true + * + * _.startsWith('abc', 'b'); + * // => false + * + * _.startsWith('abc', 'b', 1); + * // => true + */ + function startsWith(string, target, position) { + string = toString(string); + position = position == null + ? 0 + : baseClamp(toInteger(position), 0, string.length); + + target = baseToString(target); + return string.slice(position, position + target.length) == target; + } + + /** + * Creates a compiled template function that can interpolate data properties + * in "interpolate" delimiters, HTML-escape interpolated data properties in + * "escape" delimiters, and execute JavaScript in "evaluate" delimiters. Data + * properties may be accessed as free variables in the template. If a setting + * object is given, it takes precedence over `_.templateSettings` values. + * + * **Note:** In the development build `_.template` utilizes + * [sourceURLs](http://www.html5rocks.com/en/tutorials/developertools/sourcemaps/#toc-sourceurl) + * for easier debugging. + * + * For more information on precompiling templates see + * [lodash's custom builds documentation](https://lodash.com/custom-builds). + * + * For more information on Chrome extension sandboxes see + * [Chrome's extensions documentation](https://developer.chrome.com/extensions/sandboxingEval). + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category String + * @param {string} [string=''] The template string. + * @param {Object} [options={}] The options object. + * @param {RegExp} [options.escape=_.templateSettings.escape] + * The HTML "escape" delimiter. + * @param {RegExp} [options.evaluate=_.templateSettings.evaluate] + * The "evaluate" delimiter. + * @param {Object} [options.imports=_.templateSettings.imports] + * An object to import into the template as free variables. + * @param {RegExp} [options.interpolate=_.templateSettings.interpolate] + * The "interpolate" delimiter. + * @param {string} [options.sourceURL='lodash.templateSources[n]'] + * The sourceURL of the compiled template. + * @param {string} [options.variable='obj'] + * The data object variable name. + * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`. + * @returns {Function} Returns the compiled template function. + * @example + * + * // Use the "interpolate" delimiter to create a compiled template. + * var compiled = _.template('hello <%= user %>!'); + * compiled({ 'user': 'fred' }); + * // => 'hello fred!' + * + * // Use the HTML "escape" delimiter to escape data property values. + * var compiled = _.template('<%- value %>'); + * compiled({ 'value': ' + + + + + + + +
+ Frequency Analysis Input: +
+
+
+ + + diff --git a/hw2/claudio_maggioni/test.js b/hw2/claudio_maggioni/test.js new file mode 100644 index 0000000..c87397d --- /dev/null +++ b/hw2/claudio_maggioni/test.js @@ -0,0 +1,730 @@ +function tests(property, + propEqual, + jsc, + arbs, + xmlParser) { + + // simple utility functions + function words(s) { return _.words(s, /[^\s]+/g); } + function compose(f, g) { return x => f(g(x)); } + function vectorSum(arr1,arr2) { return _.zipWith(arr1, arr2, _.add); } + + window.vectorSum = vectorSum + + // how to generate sentences (for mkPrettyPrinter & mkIndenter) + let sentence = + // words are 2-12 lower letters + arbs.sentence(arbs.word(arbs.lLetter,2,12), + // prefer white space between words + arbs.oneOfWeight([arbs.whitespace, 8], + // but rarely put '\n' + [jsc.constant('\n'), 1]), + // prefer no leading whitespace + arbs.oneOfWeight([jsc.constant(''), 3], + // but sometimes add some + [arbs.whitespace, 1]), + // slightly prefer adding trailing whitespace + arbs.oneOfWeight([arbs.whitespace, 2], + // but sometimes don't + [jsc.constant(''), 1]), + // use '.', '!', '?' or '...' at the end + arbs.punctuation, + // sentence has 5 to 30 words + 5, + 30); + + test("Scalar product", function() { + property( + "doesn't change the source array", + "array number", "number", + function (arr,num) { + let copy = _.cloneDeep(arr); + let t = scalar_product(copy,num); + return propEqual(copy, arr, `scalar_product([${copy}],${num})`, `[${arr}]`); + }); + property( + "preserves the length of the array", + "array number", "number", + function (arr,num) { + return propEqual(scalar_product(arr,num).length, arr.length, `scalar_product([${arr}],${num}).length`, `${arr}.length`); + }); + property( + "returns zero array if the factor is zero", + "array number", + function (arr) { + let z = _.cloneDeep(arr); + _.fill(z,0); + return propEqual(scalar_product(arr,0),z, `scalar_product([${arr}],0)`, `[${z}]`); + }); + property( + "preserves the array if the factor is one", + "array number", + function (arr) { + let c = _.cloneDeep(arr); + return propEqual(scalar_product(arr,1),c, `scalar_product([${arr}],1))`, `[${c}]`); + }); + // have to restrict it to integers because of the rounding errors + // better to compare up to rounding error + property( + "allows factors to be combined", + "array integer", "integer", "integer", + function (arr, n1, n2) { + return propEqual(scalar_product(scalar_product(arr,n1),n2), + scalar_product(arr, n1*n2), `scalar_product(scalar_product([${arr}],${n1}),${n2})`, `scalar_product([${arr}], ${n1}*${n2})`); + }); + property( + "returns undefined if first argument is not an array", + jsc.suchthat(arbs.anything, x => !_.isArray(x)), arbs.anything, + function(notArr, x) { + return propEqual(scalar_product(notArr, x), undefined, `scalar_product(${notArr}, ${x})`, `undefined`); + }); + property( + "if factor is not passed, array is returned as is", + "array number", + function(arr) { + return propEqual(scalar_product(arr), arr, `scalar_product([${arr}])`, `[${arr}]`); + }); + }); + + test("Inner product", function() { + property( + "doesn't change the source arrays", + arbs.equalLengthArrays(jsc.number, jsc.number), + function (arrs) { + let [a1,a2] = arrs; + let copy1 = _.cloneDeep(a1); + let copy2 = _.cloneDeep(a2); + var t = inner_product(a1,a2); + return propEqual(a1,copy1) && propEqual(a2,copy2); + }); + property( + "is symmetric", + arbs.equalLengthArrays(jsc.number, jsc.number), + function (arrs) { + let [a1,a2] = arrs; + return propEqual(inner_product(a1,a2), inner_product(a2,a1), `inner_product([${a1}],[${a2}])`, `inner_product([${a2}],[${a1}])`); + }); + property( + "returns non-negative number when multiplying vector to itself", + "array number", + function (arr) { + return inner_product(arr,arr) >= 0; + }); + property( + "returns 0 if one of the vectors is a zero-filled [0,...,0] vector", + "array number", + function (arr) { + let z = new Array(arr.length); + _.fill(z,0); + return propEqual(inner_product(arr,z), 0, `inner_product([${arr}],[${z}])`, `0`); + }); + property( + "if argument arrays sizes don't match, returns undefined", + jsc.array(arbs.anything), + function(arr1) { + return jsc.forall( + jsc.suchthat(jsc.array(arbs.anything), + x => x.length !== arr1.length), + function(arr2) { + return propEqual(inner_product(arr1,arr2), undefined, `inner_product([${arr1}],[${arr2}])` , `undefined`); + }); + }); + }); + + test("mapReduce", function() { + // mapReduce is pretty agnostic to the array contents + // so we could use "json" arbitrary instead of "number" + // to get better coverage + // Unfortunately, it is also quite slower + property( + "doesn't change the source array", + "array integer", "integer -> integer", + function (arr, f) { + let copy = _.cloneDeep(arr); + let t = mapReduce(copy, f); + return propEqual(copy, arr, `[${copy}]`,`[${arr}]`); + }); + property( + "mapReduce([],f,g,seed) == seed", + "integer -> integer", arbs.fn2(jsc.integer), "integer", + function(f, combine, seed) { + return propEqual(mapReduce([],f,combine,seed), seed, `mapReduce([],${f},${combine},${seed})`, `${seed}`); + }); + property( + "mapReduce(arr,identity,combine,seed) == reduce(arr,combine,seed)", + "array integer", arbs.fn2(jsc.integer), "integer", + function (arr, combine, seed) { + return propEqual(mapReduce(arr,_.identity,combine,seed), + _.reduce(arr,combine,seed), `mapReduce([${arr}],${_.identity},${combine},${seed})`, `_.reduce([${arr}],${combine},${seed})`); + }); + property( + "mapReduce(arr,f,combine,seed) == " + + "mapReduce(arr,identity,(a,x) => combine(a,f(x)),f(seed))", + "array integer", "integer -> integer", arbs.fn2(jsc.integer), + "integer", + function (arr, f, combine, seed) { + return propEqual( + mapReduce(arr,f,combine,seed), + mapReduce(arr,_.identity,(a,x) => combine(a,f(x)),seed), `mapReduce([${arr}],${f},${combine},${seed})`, `mapReduce([${arr}],${_.identity},(a,x) => ${combine}(a,${f}(x)),${seed})`); + }); + property( + "mapReduce(arr1.concat(arr2),f) == mapReduce(arr1,f) + mapReduce(arr2,f)", + "array integer", "array integer", "integer -> integer", + function (arr1, arr2, f) { + return propEqual( + mapReduce(arr1.concat(arr2),f), + mapReduce(arr1,f) + mapReduce(arr2,f), `mapReduce([${arr1}].concat([${arr2}]),${f})`, `mapReduce([${arr1}],${f}) + mapReduce([${arr2}],${f})`); + }); + property( + "mapReduce(arr1.concat(arr2),f,+,0) == " + + "mapReduce(arr1,f,+,0) + mapReduce(arr2,f,+,0)", + "array integer", "array integer", "integer -> integer", + function (arr1, arr2, f) { + return propEqual( + mapReduce(arr1.concat(arr2),f, _.add, 0), + mapReduce(arr1,f,_.add,0) + mapReduce(arr2,f,_.add,0), `mapReduce([${arr1}].concat([${arr2}]),${f}, ${_.add}, 0)`, `mapReduce([${arr1}],${f},${_.add},0) + mapReduce([${arr2}],${f},${_.add},0)`); + }); + property( + "mapReduce(arr,f,(a,x) => a.concat([x]),[]) == map(arr,f)", + "array integer", "integer -> integer", + function (arr, f) { + return propEqual(mapReduce(arr,f,(a,x) => a.concat([x]), []), + _.map(arr,f), `mapReduce([${arr}],${f},(a,x) => a.concat([x]), [])`, `${_.map(arr,f)}`); + }); + property( + "mapReduce(arr,f,(a,x) => a.concat(x),[]) == flatMap(arr,f)", + "array integer", "integer -> array integer", + function (arr,f) { + return propEqual(mapReduce(arr,f,(a,x) => a.concat(x),[]), + _.flatMap(arr,f), `mapReduce([${arr}],${f},(a,x) => a.concat(x),[])`, + `[${_.flatMap(arr,f)}]`); + }); + property( + "mapReduce([1,2,3],f,g,0) == g(g(g(0,f(1)),f(2)),f(3))", + "integer -> integer", arbs.fn2(jsc.integer), + function (f, g) { + return propEqual(mapReduce([1,2,3],f,g,0), + g(g(g(0,f(1)),f(2)),f(3)), `mapReduce([1,2,3],${f},${g},0)`, `${g(g(g(0,f(1)),f(2)),f(3))}`); + }); + property( + "if the first argument is not an array, returns undefined", + jsc.suchthat(arbs.anything, x => !Array.isArray(x)), + "number -> number", + function(notArr, f) { + return propEqual(mapReduce(notArr,f), undefined); + }); + property( + "if the second argument is not a function, returns undefined", + "array integer", jsc.suchthat(arbs.anything, x => typeof x !== 'function'), + function(arr, notF) { + return propEqual(mapReduce(arr,notF), undefined); + }); + }); + + test("mergeSortedArrays", function() { + property( + "doesn't change the source arrays", + arbs.sortedArray(jsc.integer), arbs.sortedArray(jsc.integer), + function(a, b) { + let copy1 = _.cloneDeep(a); + let copy2 = _.cloneDeep(b); + let t = mergeSortedArrays(copy1,copy2); + return propEqual(copy1,a) && propEqual(copy2,b); + }); + property( + "produces sorted results", + arbs.sortedArray(jsc.integer), arbs.sortedArray(jsc.integer), + function(a, b) { + let t = mergeSortedArrays(a,b); + return propEqual(t, _.sortBy(t), `[${t}]`,`mergeSortedArrays([${a}],[${b}])`); + }); + property( + "has length equal to the sum of individual lengths", + arbs.sortedArray(jsc.integer), arbs.sortedArray(jsc.integer), + function(a, b) { + return propEqual(mergeSortedArrays(a,b).length, a.length + b.length, `mergeSortedArrays([${a}],[${b}]).length`, `[${a}].length + [${b}].length`); + }); + }); + + test("range", function() { + property( + "results in undefined if step is zero", + "integer", "integer", + function(x,y) { + return propEqual(range(x,y,0), undefined, `range(${x},${y},0)`, undefined, `[${range(x,y,0)}]`); + }); + property( + "results in empty array if x > y and step > 0 or x < y and step < 0", + "integer", + function(x) { + return jsc.forall( + jsc.suchthat(jsc.integer, y => y != x), arbs.posInteger, + function(y,stepMod) { + let s = x>y ? stepMod : -stepMod + return propEqual(range(x,y,s), [], `range(${x},${y},${s})`, undefined, `[${range(x,y,s)}]`); + }); + }); + property( + "produces array without repetitions", + "integer", "integer", jsc.suchthat(jsc.integer, x => x != 0), + function(x,y,step) { + let r = range(x,y,step); + return propEqual(r.length, _.uniq(r).length, `range(${x},${y},${step})`, undefined, `[${range(x,y,step)}]`); + }); + property( + "produces array with all elements >= min(x,y)", + "integer", "integer", jsc.suchthat(jsc.integer, x => x != 0), + function(x,y,step) { + let r = range(x,y,step); + let l = _.min([x,y]); + return propEqual(_.every(r,a => a >= l), true, `range(${x},${y},${step})`, undefined, `[${range(x,y,step)}]`); + }); + property( + "produces array with all elements <= max(x,y)", + "integer", "integer", jsc.suchthat(jsc.integer, x => x != 0), + function(x,y,step) { + let r = range(x,y,step); + let h = _.max([x,y]); + return propEqual(_.every(r,a => a <= h), true, `range(${x},${y},${step})`, undefined, `[${range(x,y,step)}]`); + }); + property( + "returns undefined, if either argument is not a number", + "number", "number", jsc.suchthat(jsc.number, x => x != 0), + jsc.suchthat(arbs.anything, x => !_.isNumber(x) || _.isNaN(x)), + jsc.suchthat(arbs.anything, x => !_.isNumber(x) || _.isNaN(x)), + jsc.suchthat(arbs.anything, x => !_.isNumber(x) || _.isNaN(x)), + jsc.suchthat(arbs.anything, x => !_.isUndefined(x) && + (!_.isNumber(x) || _.isNaN(x))), + function(x,y,step,nN1,nN2,nN3,nN4) { + return propEqual(range(nN1,nN2,step), undefined) && + propEqual(range(nN1,y,step), undefined) && + propEqual(range(x,nN2,step), undefined) && + propEqual(range(nN1,nN2,nN3), undefined) && + propEqual(range(x,y,nN4), undefined) && + propEqual(range(nN1,y,nN3), undefined) && + propEqual(range(x,nN2,nN3), undefined); + }); + }); + + test("flatten", function() { + property( + "doesn't change the input array", + "array json", + function(a) { + let copy = _.cloneDeep(a); + let t = flatten(copy); + return propEqual(copy, a, `flatten([${a}])`); + }); + property( + "simply returns the input, if it is not an array", + jsc.oneof(jsc.number, jsc.bool, jsc.falsy, jsc.string), + function(inp) { + return propEqual(flatten(inp), inp, `flatten(${inp})`); + }); + property( + "simply returns the input, if it is already flattened", + jsc.array(jsc.oneof(jsc.number, jsc.bool, jsc.falsy, jsc.string)), + function(a) { + return propEqual(flatten(a), a, `flatten([${a}])`, `[${a}]`); + }); + property( + "flatten([arr]) == flatten(arr)", + "array json", + function(a) { + return propEqual(flatten([a]), flatten(a), `flatten([[${a}]])`, `flatten([${a}])`); + }); + }); + + test("mkPrettyPrinter", function() { + property( + "output has no too long lines", + jsc.integer(20,80), jsc.array(sentence), + function(ls, input) { + let inp = input.join('\n'); + let pp = mkPrettyPrinter(ls); + let r = pp(inp); + return propEqual(_.every(r, l => l.length <= ls), true, `mkPrettyPrinter(${ls})("${inp.replace(/\n/, '\\n')}")`, undefined, `[${mkPrettyPrinter(ls)(inp)}]`); + }); + property( + "output has all input words in the same order", + jsc.integer(20,80), jsc.array(sentence), + function(ls, input) { + let inp = input.join('\n'); + let ws = words(inp); + let pp = mkPrettyPrinter(ls); + let r = pp(inp); + return propEqual(words(r.join('\n')), ws, `mkPrettyPrinter(${ls})("${inp.replace(/\n/, '\\n')}")`, undefined); + }); + property( + "output has no leading or trailing white spaces", + jsc.integer(20,80), jsc.array(sentence), + function(ls, input) { + let inp = input.join('\n'); + let pp = mkPrettyPrinter(ls); + let r = pp(inp); + return propEqual(_.every(r, l => (l == _.trim(l))), true, `mkPrettyPrinter(${ls})("${inp.replace(/\n/, '\\n')}")`, undefined, `[${mkPrettyPrinter(ls)(inp)}]`); + }); + property( + "does not use global variables", + arbs.vect(jsc.integer(20,80),5), + arbs.permutation(5), jsc.array(sentence), + function(lss, perm, input) { + let inp = input.join('\n'); + let pps = lss.map(mkPrettyPrinter); + for (let i in perm) { + let j = perm[i]; + let r = pps[j](inp); + _.every(r, l => propEqual(l.length <= lss[j], true)); + pps.splice(j,1); + lss.splice(j,1); + } + return true; + }); + property( + "returns undefined if called with not a number", + jsc.suchthat(arbs.anything, x => !_.isUndefined(x) && + (!_.isNumber(x) || _.isNaN(x))), + function(nN) { + return propEqual(mkPrettyPrinter(nN), undefined, `mkPrettyPrinter(${nN})`); + }); + property( + "if pretty-printer is called with non-string, it returns undefined", + jsc.integer(50,80), + jsc.suchthat(arbs.anything, x => !_.isString(x)), + function(ls, nStr) { + return propEqual(mkPrettyPrinter(ls)(nStr), undefined, `mkPrettyPrinter(${ls})(${nStr})`); + }); + }); + + test("mkIndenter", function() { + let indenterInput = jsc.oneof(jsc.nat(20), sentence, jsc.array(sentence)); + // it's easier to generate absolute indentation levels + // and then turn them into relative ones + function fixIndentationLevels(arr,curLvl) { + for (let i in arr) { + if (typeof arr[i] == "number") { + let t = arr[i]; + arr[i] -= curLvl; + curLvl = t; + } + } + return curLvl; + } + function properlyIndented(il) { + return l => { + let b = l.substr(0,il); + let e = l.slice(il); + return propEqual(b, ' '.repeat(il)) && + propEqual(e, _.trim(e)) && + ! _.includes(e, '\n') && + ! _.includes(e, '\t') && + ! _.includes(e, ' '); + }; + } + function properlyIndentedLI(il) { + return (l,ix) => { + let b = l.substr(0,il+2); + let e = l.slice(il+2); + let expectedIndent = i ? ' '.repeat(il+2) : ' '.repeat(il) + '* '; + return propEqual(b, expectedIndent) && + propEqual(e, _.trim(e)) && + ! _.includes(e, '\n') && + ! _.includes(e, '\t') && + ! _.includes(e, ' '); + }; + } + function noEarlyWraps(ls, ss, rl, el, ol) { + let lss = _.initial(ss).map(x => x.length); + let nexts = _.tail(ss).map(x => words(x)[0].length); + return propEqual(_.every(_.zipWith(lss,nexts,_.add), s => s >= ls),true,rl,el,ol); + } + + property( + "returned function doesn't change its argument", + jsc.integer(50,80), jsc.nat(12), jsc.array(sentence), + function(ls, il, arr) { + let copy = _.cloneDeep(arr); + let i = mkIndenter(ls, il); + let t = i(copy); + return propEqual(copy,arr, `mkIndenter(${ls}, ${il})([${arr}])`); + }); + property( + "freshly created indenter returns indentation level passed " + + "during creation", + jsc.integer(50,80), jsc.nat(20), + function(ls, il) { + let i = mkIndenter(ls, il); + return propEqual(i(true), il, `mkIndenter(${ls}, ${il})(true)`); + }); + property( + "freshly created indenter returns an empty array", + jsc.integer(50,80), jsc.nat(20), + function(ls, il) { + let i = mkIndenter(ls, il); + return propEqual(i(), [], `mkIndenter(${ls}, ${il})()`); + }); + property( + "content request doesn't change the indentation level", + jsc.integer(50,80), jsc.nat(20), jsc.array(indenterInput), + function(ls, il, arr) { + fixIndentationLevels(arr,il); + let i = mkIndenter(ls, il); + arr.forEach(i); + let il2 = i(true); + i(); + return propEqual(i(true), il2, `var i = mkIndenter(${ls}, ${il});i(true);i(true)`); + }); + property( + "output doesn't have too long lines", + jsc.integer(50,80), jsc.nat(20), jsc.array(indenterInput), + function(ls, il, arr) { + fixIndentationLevels(arr,il); + let i = mkIndenter(ls, il); + arr.forEach(i); + let r = i(); + return propEqual(_.every(r, l => l.length <= ls), true, `mkIndenter(${ls}, ${il})()`); + }); + property( + "integer input doesn't produce any output and changes the " + + "indentation level", + jsc.integer(50,80), jsc.nat(12), jsc.integer(-12,12), + function(ls, il, int) { + let i = mkIndenter(ls, il); + i(int); + return propEqual(i(true), il + int, `var i = mkIndenter(${ls}, ${il}); i(${int}); i(true); i()`) && + propEqual(i(), [], `var i = mkIndenter(${ls}, ${il}); i(${int}); i(true); i()`); + }); + property( + "string input produces properly indented results " + + "and doesn't change the indentation level", + jsc.integer(50,80), jsc.nat(20), sentence, + function(ls, il, s) { + let i = mkIndenter(ls, il); + i(s); + let r = i(); + return propEqual(_.every(r, properlyIndented(il)), true, `var i = mkIndenter(${ls}, ${il}); i("${s}"); i(); i(true)`) && + propEqual(i(true), il, `var i = mkIndenter(${ls}, ${il}); i("${s}"); i(); i(true)`); + }); + property( + "string input doesn't wrap lines too early", + jsc.integer(50,80), jsc.nat(20), sentence, + function(ls, il, s) { + let i = mkIndenter(ls, il); + i(s); + let r = i(); + return noEarlyWraps(ls, r, `var i = mkIndenter(${ls}, ${il}); i("${s.replace(/\n/, '\\n')}"); i()`, undefined, `[${i()}]`); + }); + property( + "empty array input does nothing", + jsc.integer(50,80), jsc.nat(20), + function(ls, il) { + let i = mkIndenter(ls, il); + i([]); + return propEqual(i(), [], `var i = mkIndenter(${ls}, ${il}); i([]); i(); i(true)`) && propEqual(i(true), il, `var i = mkIndenter(${ls}, ${il}); i([]); i(); i(true)`); + }); + property( + "it doesn't use global variables", + jsc.integer(2,5), + function(n) { + let inputsArb = arbs.vect(jsc.tuple([jsc.integer(50,80), + jsc.nat(20), + jsc.array(sentence)]), + n); + return jsc.forall( + inputsArb, + function(inputs) { + let seqOuts = _.map(inputs, inp => { + let i = mkIndenter(inp[0],inp[1]); + inp[2].forEach(i); + return i(); + }); + let sz = _.sum(_.map(inputs, x => x[2].length)) + 2*n; + return jsc.forall( + arbs.vect(jsc.nat(n-1), sz), + function(schedule) { + let cnts = _.fill(Array(n), -1); + let outs = _.fill(Array(n), undefined); + let is = []; + schedule.forEach(i_ => { + let i = i_; + for (; cnts[i] > inputs[i][2].length; i++, i %= n); + let inp = inputs[i]; + if (cnts[i] == -1) + is[i] = mkIndenter(inp[0], inp[1]); + else if (cnts[i] == inp[2].length) + outs[i] = is[i](); + else + is[i](inp[2][cnts[i]]); + cnts[i]++; + }); + let os = _.zip(seqOuts, outs); + return _.every(os, o => propEqual(o[0], o[1])); + }); + }); + }); + property( + "returns undefined if either argument is not a number", + jsc.suchthat(arbs.anything, x => !_.isNumber(x) || _.isNaN(x)), + jsc.suchthat(arbs.anything, x => !_.isUndefined(x) && + (!_.isNumber(x) || _.isNaN(x))), + jsc.integer(50,80), jsc.nat(20), + function(nN1, nN2, ls, il) { + return propEqual(mkIndenter(nN1), undefined) && + propEqual(mkIndenter(nN1,il), undefined) && + propEqual(mkIndenter(ls,nN2), undefined) && + propEqual(mkIndenter(nN1,nN2), undefined); + }); + property( + "sample input works", + "unit", + function(u) { + let i = mkIndenter(20); + i("Short line"); + i("This line is longer than 20 characters"); + i(8); + i("Big indent"); + i("Not so long line"); + i(-6); + i("Small indent"); + i(["Item 1", "Item 2", "Really really long Item 3"]); + return propEqual(i(), + [ 'Short line', + 'This line is longer', + 'than 20 characters', + ' Big indent', + ' Not so long', + ' line', + ' Small indent', + ' * Item 1', + ' * Item 2', + ' * Really really', + ' long Item 3' ]); + }); + }); + + test("letter_frequency", function() { + property( + "Concatenation of strings produces merge of maps", + jsc.array(arbs.letter), jsc.array(arbs.letter), + function(arr1, arr2) { + let s1 = arr1.join(''); + let s2 = arr2.join(''); + let expected = _.assignWith(letter_frequency(s1), + letter_frequency(s2), + _.add); + return propEqual(letter_frequency(s1 + s2), expected); + }); + property( + "Map values are always positive", + jsc.array(arbs.letter), + function(arr) { + let s = arr.join(''); + let r = letter_frequency(s); + return _.every(r, x => x > 0); + }); + property( + "Hello example works", + "unit", + function(u) { + let a = []; a.H = 1; a.E = 1; a.L = 2; a.O = 1; + let expected = {'H' : 1,'E' : 1,'L' : 2,'O' : 1} + + try { + propEqual(letter_frequency('Hello'), expected) + } catch(e) { + return propEqual(letter_frequency('Hello'),a) + } + + try { + propEqual(letter_frequency('Hello'),a) + } catch(e) { + return propEqual(letter_frequency('Hello'), expected) + } + + return true + }); + }); + + test("display_letter_frequency", function() { + // how to generate frequency table + let fTable = jsc.array(jsc.tuple([arbs.uLetter, arbs.posInteger])).smap( + _.fromPairs, + _.toPairs); + + property( + "first arguments is not modified", + fTable, + function(ft) { + let copy = _.cloneDeep(ft); + let dom = {}; + display_letter_frequency(copy, dom); + return propEqual(copy, ft); + }); + property( + "Output is a table with right number of rows and 2 columns", + fTable, + function(ft) { + let dom = {}; + display_letter_frequency(ft, dom); + let out = xmlParser.parseFromString(dom.innerHTML, 'text/xml'); + let d = out.documentElement; + let cs = d.children; + return propEqual(d.tagName, 'table') && + propEqual(cs.length, _.size(ft)) && + _.every(_.range(cs.length).map(i => { + let c = cs.item(i); + let subcs = c.children; + return propEqual(c.tagName, 'tr') && + propEqual(subcs.length, 2) && + _.every(_.range(subcs.length).map(j => { + let subc = subcs.item(j); + return propEqual(subc.tagName, 'td') && + propEqual(subc.children.length, 0); + })); + })); + }); + property( + "Every row has key/value pair from the frequency table", + fTable, + function(ft) { + function isInMap(k,v) { + let i = parseInt(v); + return propEqual(i + '', v) && + propEqual(ft[k], i); + } + let dom = {}; + display_letter_frequency(ft, dom); + let out = xmlParser.parseFromString(dom.innerHTML, 'text/xml'); + let d = out.documentElement; + let cs = d.children; + return propEqual(d.tagName, 'table') && + _.every(_.range(cs.length).map(i => { + let c = cs.item(i); + let subcs = c.children; + return propEqual(c.tagName, 'tr') && + propEqual(subcs.length,2) && + propEqual(subcs.item(0).tagName, 'td') && + propEqual(subcs.item(1).tagName, 'td') && + isInMap(subcs.item(0).innerHTML, subcs.item(1).innerHTML); + })); + }); + property( + "Does nothing if either argument is not an object", + fTable, + jsc.dict(arbs.anything), + jsc.suchthat(arbs.anything, x => !_.isObject(x)), + jsc.suchthat(arbs.anything, x => !_.isObject(x)), + jsc.suchthat(arbs.anything, x => !_.isObject(x)), + function(ft, nO1, nO2, nO3, o) { + let copyO = _.cloneDeep(o); + let copyNO2 = _.cloneDeep(nO2); + let copyNO3 = _.cloneDeep(nO3); + display_letter_frequency(nO1, copyNO2); + display_letter_frequency(nO1, copyO); + display_letter_frequency(ft, copyNO3); + return propEqual(copyNO2, nO2) && + propEqual(copyO, o) && + propEqual(copyNO3, nO3); + }); + }); +}