|
|||||||||
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.UnknownType
public class UnknownType
The Unknown
type.
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 | ||
---|---|---|
boolean |
canAssignTo(JSType that)
Tests whether values of this type can be safely assigned
to values of that type. |
|
boolean |
canBeCalled()
This predicate is used to test whether a given type can be used as the 'function' in a function call. |
|
FunctionType |
getConstructor()
Gets this object's constructor. |
|
String |
getDisplayName()
Returns a user meaningful label for the JSType instance. |
|
ObjectType |
getImplicitPrototype()
Gets the implicit prototype (a.k.a. |
|
BooleanLiteralSet |
getPossibleToBooleanOutcomes()
Computes the set of possible outcomes of the ToBoolean predicate
for this type. |
|
int |
getPropertiesCount()
Gets the number of properties of this object. |
|
JSType |
getPropertyType(String propertyName)
Gets the property type of the property whose name is given. |
|
String |
getReferenceName()
Gets the reference name for this object. |
|
ObjectType.Property |
getSlot(String name)
Returns any defined slot within this scope for this name. |
|
boolean |
hasDisplayName()
|
|
boolean |
hasProperty(String propertyName)
Checks whether the property whose name is given is present on the object. |
|
boolean |
isCheckedUnknownType()
|
|
boolean |
isNullable()
Tests whether this type is nullable. |
|
boolean |
isPropertyTypeDeclared(String propertyName)
Checks whether the property's type is declared. |
|
boolean |
isPropertyTypeInferred(String propertyName)
Checks whether the property's type is inferred. |
|
boolean |
isSubtype(JSType that)
Checks whether this is a subtype of that . |
|
boolean |
isUnknownType()
We treat this as the unknown type if any of its implicit prototype properties is unknown. |
|
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. |
|
TernaryValue |
testForEquality(JSType that)
Compares this and that . |
|
|
visit(Visitor<T> visitor)
Visit this type with the given visitor. |
Methods inherited from class java.lang.Object |
---|
clone, finalize, getClass, notify, notifyAll, wait, wait, wait |
Method Detail |
---|
public ObjectType.Property getSlot(String name)
StaticScope
getSlot
in interface StaticScope<JSType>
getSlot
in class ObjectType
name
- The name of the variable slot to look up.
null
if no
definition exists.public boolean isUnknownType()
ObjectType
isUnknownType
in class ObjectType
public boolean isCheckedUnknownType()
isCheckedUnknownType
in class JSType
public boolean canAssignTo(JSType that)
JSType
this
type can be safely assigned
to values of that
type.
The default implementation verifies that this
is a subtype
of that
.
canAssignTo
in class JSType
public boolean canBeCalled()
JSType
canBeCalled
in class JSType
true
if this type might be callable.public boolean matchesNumberContext()
JSType
matchesNumberContext
in class JSType
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 JSType
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 JSType
public TernaryValue testForEquality(JSType that)
JSType
this
and that
.
testForEquality
in class ObjectType
TernaryValue.TRUE
if the comparison of values of
this
type and that
always succeed (such as
undefined
compared to null
)TernaryValue.FALSE
if the comparison of values of
this
type and that
always fails (such as
undefined
compared to number
)TernaryValue.UNKNOWN
if the comparison can succeed or
fail depending on the concrete valuespublic boolean isNullable()
JSType
isNullable
in class JSType
public boolean isSubtype(JSType that)
JSType
this
is a subtype of that
.Subtyping rules:
(T<sub>1</sub>, …, T<sub>n</sub>) <: U
if and only
T<sub>k</sub> <: U
for all k ∈ 1..n
.U <: (T<sub>1</sub>, …, T<sub>n</sub>)
if and only
if U <: T<sub>k</sub>
for some index k
.O<sub>1</sub>
is a subtype
of an object O<sub>2</sub>
if it has more properties
than O<sub>2</sub>
and all common properties are
pairwise subtypes.
isSubtype
in class JSType
this <: that
public <T> T visit(Visitor<T> visitor)
JSType
visit
in class ObjectType
Visitor
public ObjectType getImplicitPrototype()
ObjectType
[[Prototype]]
property).
getImplicitPrototype
in class ObjectType
public int getPropertiesCount()
ObjectType
getPropertiesCount
in class ObjectType
public JSType getPropertyType(String propertyName)
ObjectType
getPropertyType
in class ObjectType
UnknownType
. This method never
returns null
.public boolean hasProperty(String propertyName)
ObjectType
hasProperty
in class ObjectType
public FunctionType getConstructor()
ObjectType
getConstructor
in class ObjectType
null
if it is a native
object (constructed natively v.s. by instantiation of a function)public String getReferenceName()
ObjectType
getReferenceName
in class ObjectType
null
if this is an anonymous
objectpublic String getDisplayName()
JSType
getDisplayName
in class ObjectType
public boolean hasDisplayName()
hasDisplayName
in class JSType
public boolean isPropertyTypeDeclared(String propertyName)
ObjectType
isPropertyTypeDeclared
in class ObjectType
public boolean isPropertyTypeInferred(String propertyName)
ObjectType
isPropertyTypeInferred
in class ObjectType
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
|
|||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | ||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |