|
|||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | ||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |
java.lang.Objectcom.google.javascript.rhino.jstype.JSType
com.google.javascript.rhino.jstype.ObjectType
com.google.javascript.rhino.jstype.FunctionType
com.google.javascript.rhino.jstype.NoObjectType
com.google.javascript.rhino.jstype.NoType
public class NoType
Bottom type, representing the subclass of any value or object.
Although JavaScript programmers can't explicitly denote the bottom type,
it comes up in static analysis. For example, if we have:
var x = null;
if (x) {
f(x);
}
We need to be able to assign x
a type within the f(x)
call. Since it has no possible type, we assign x
the NoType,
so that f(x)
is legal no matter what the type of f
's
first argument is.
Nested Class Summary |
---|
Nested classes/interfaces inherited from class com.google.javascript.rhino.jstype.ObjectType |
---|
ObjectType.Property |
Nested classes/interfaces inherited from class com.google.javascript.rhino.jstype.JSType |
---|
JSType.TypePair |
Field Summary |
---|
Fields inherited from class com.google.javascript.rhino.jstype.JSType |
---|
EMPTY_TYPE_COMPONENT, ENUMDECL, NOT_A_CLASS, NOT_A_TYPE, NOT_ENUMDECL, UNKNOWN_NAME |
Method Summary | ||
---|---|---|
Iterable<ObjectType> |
getCtorExtendedInterfaces()
Gets the interfaces extended by the interface associated with this type. |
|
Iterable<ObjectType> |
getCtorImplementedInterfaces()
Gets the interfaces implemented by the ctor associated with this type. |
|
FunctionType |
getOwnerFunction()
Gets the owner of this if it's a function prototype. |
|
BooleanLiteralSet |
getPossibleToBooleanOutcomes()
Computes the set of possible outcomes of the ToBoolean predicate
for this type. |
|
Node |
getPropertyNode(String propertyName)
Gets the node corresponding to the definition of the specified property. |
|
boolean |
hasOwnProperty(String propertyName)
Checks whether the property whose name is given is present directly on the object. |
|
boolean |
hasReferenceName()
Returns true if the object is named. |
|
boolean |
isNativeObjectType()
Whether this is a built-in object. |
|
boolean |
isNoObjectType()
|
|
boolean |
isNoType()
|
|
boolean |
isNullable()
Tests whether this type is nullable. |
|
boolean |
isPropertyInExterns(String propertyName)
Checks whether the property was defined in the externs. |
|
boolean |
isPropertyTypeDeclared(String property)
Checks whether the property's type is declared. |
|
boolean |
isSubtype(JSType that)
A function is a subtype of another if their call methods are related via subtyping and this is a subtype of that with regard to
the prototype chain. |
|
void |
matchConstraint(ObjectType constraintObj)
Modify this type so that it matches the specified type. |
|
boolean |
matchesNumberContext()
This predicate is used to test whether a given type can appear in a numeric context, such as an operand of a multiply operator. |
|
boolean |
matchesObjectContext()
This predicate is used to test whether a given type can appear in an Object context, such as the expression in a with statement. |
|
boolean |
matchesStringContext()
This predicate is used to test whether a given type can appear in a String context, such as an operand of a string concat (+) operator. |
|
JSType |
unboxesTo()
Gets the type to which this type unboxes. |
|
|
visit(Visitor<T> visitor)
Visit this type with the given visitor. |
Methods inherited from class com.google.javascript.rhino.jstype.NoObjectType |
---|
getConstructor, getImplicitPrototype, getOwnPropertyJSDocInfo, getPropertiesCount, getPropertyType, getReferenceName, hashCode, hasProperty, isEquivalentTo, isPropertyTypeInferred, removeProperty, setPropertyJSDocInfo, toMaybeFunctionType |
Methods inherited from class com.google.javascript.rhino.jstype.ObjectType |
---|
cast, createDelegateSuffix, defineDeclaredProperty, defineInferredProperty, findPropertyType, getDisplayName, getIndexType, getJSDocInfo, getNormalizedReferenceName, getOwnSlot, getParameterType, getParentScope, getPropertyNames, getRootNode, isFunctionPrototypeType, isObject, isUnknownType, setJSDocInfo, testForEquality |
Methods inherited from class java.lang.Object |
---|
clone, finalize, getClass, notify, notifyAll, wait, wait, wait |
Method Detail |
---|
public boolean isNoObjectType()
isNoObjectType
in class NoObjectType
public boolean isNoType()
isNoType
in class JSType
public boolean isNullable()
JSType
isNullable
in class JSType
public boolean isSubtype(JSType that)
FunctionType
this
is a subtype of that
with regard to
the prototype chain.
isSubtype
in class NoObjectType
this <: that
public BooleanLiteralSet getPossibleToBooleanOutcomes()
JSType
ToBoolean
predicate
for this type. The ToBoolean
predicate is defined by the ECMA-262
standard, 3rd edition. Its behavior for simple types can be
summarized by the following table:
type | result |
---|---|
undefined | {false} |
null | {false} |
boolean | {true, false} |
number | {true, false} |
string | {true, false} |
Object | {true} |
getPossibleToBooleanOutcomes
in class ObjectType
public boolean matchesNumberContext()
JSType
matchesNumberContext
in class NoObjectType
public boolean matchesObjectContext()
JSType
Object
context, such as the expression in a with statement.
Most types we will encounter, except notably null
, have at least
the potential for converting to Object
. Host defined objects can
get peculiar.
matchesObjectContext
in class NoObjectType
public boolean matchesStringContext()
JSType
String
context, such as an operand of a string concat (+) operator.
All types have at least the potential for converting to String
.
When we add externally defined types, such as a browser OM, we may choose
to add types that do not automatically convert to String
.
matchesStringContext
in class NoObjectType
public <T> T visit(Visitor<T> visitor)
JSType
visit
in class NoObjectType
Visitor
public boolean hasOwnProperty(String propertyName)
ObjectType
hasOwnProperty
in class ObjectType
public boolean isPropertyTypeDeclared(String property)
ObjectType
isPropertyTypeDeclared
in class ObjectType
public boolean isPropertyInExterns(String propertyName)
ObjectType
isPropertyInExterns
in class ObjectType
public Node getPropertyNode(String propertyName)
ObjectType
getPropertyNode
in class ObjectType
propertyName
- the name of the property
Node
corresponding to the property or null.public JSType unboxesTo()
JSType
unboxesTo
in class JSType
null
if this type does not unbox.public boolean hasReferenceName()
ObjectType
hasReferenceName
in class ObjectType
public boolean isNativeObjectType()
isNativeObjectType
in class ObjectType
public FunctionType getOwnerFunction()
ObjectType
getOwnerFunction
in class ObjectType
public Iterable<ObjectType> getCtorImplementedInterfaces()
ObjectType
getCtorImplementedInterfaces
in class ObjectType
public Iterable<ObjectType> getCtorExtendedInterfaces()
ObjectType
getCtorExtendedInterfaces
in class ObjectType
public void matchConstraint(ObjectType constraintObj)
JSType
matchConstraint
in class JSType
|
|||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | ||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |