Class NoType
java.lang.Object
com.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
- All Implemented Interfaces:
StaticScope<JSType>
,Serializable
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.- See Also:
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Nested Class Summary
Nested classes/interfaces inherited from class com.google.javascript.rhino.jstype.JSType
JSType.TypePair
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Field Summary
Fields inherited from class com.google.javascript.rhino.jstype.JSType
EMPTY_TYPE_COMPONENT, ENUMDECL, NOT_A_CLASS, NOT_A_TYPE, NOT_ENUMDECL, templateTypeMap, UNKNOWN_NAME
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Method Summary
Modifier and TypeMethodDescriptionGets the interfaces extended by the interface associated with this type.Gets the interfaces implemented by the ctor associated with this type.Gets the owner of this if it's a function prototype.Computes the set of possible outcomes of theToBoolean
predicate for this type.boolean
Returns true if the object is named.boolean
Whether this is a built-in object.boolean
boolean
isNoType()
boolean
Tests whether this type is nullable.boolean
A function is a subtype of another if their call methods are related via subtyping andthis
is a subtype ofthat
with regard to the prototype chain.void
matchConstraint
(JSType constraint) Modify this type so that it matches the specified type.boolean
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
This predicate is used to test whether a given type can appear in anObject
context, such as the expression in a with statement.boolean
This predicate is used to test whether a given type can appear in aString
context, such as an operand of a string concat (+) operator.void
matchRecordTypeConstraint
(ObjectType constraintObj) Turn an object type to its corresponding scalar type.<T> T
Visit this type with the given visitor.Methods inherited from class com.google.javascript.rhino.jstype.NoObjectType
getConstructor, getImplicitPrototype, getReferenceName, hashCode, removeProperty, setPropertyJSDocInfo, toMaybeFunctionType
Methods inherited from class com.google.javascript.rhino.jstype.FunctionType
canBeCalled, clearCachedValues, cloneWithoutArrowType, getAllExtendedInterfaces, getAllImplementedInterfaces, getBindReturnType, getExtendedInterfaces, getExtendedInterfacesCount, getImplementedInterfaces, getInstanceType, getMaxArguments, getMinArguments, getOwnImplementedInterfaces, getOwnPropertyNames, getParameters, getParametersNode, getPropertyType, getPrototype, getReturnType, getSlot, getSource, getSubTypes, getSuperClassConstructor, getTopDefiningInterface, getTopMostDefiningType, getTypeOfThis, hasAnyTemplateTypesInternal, hasCachedValues, hasEqualCallType, hasImplementedInterfaces, hasInstanceType, isConstructor, isInstanceType, isInterface, isOrdinaryFunction, isReturnTypeInferred, makesDicts, makesStructs, setDict, setExtendedInterfaces, setImplementedInterfaces, setPrototypeBasedOn, setSource, setStruct, toDebugHashCodeString
Methods inherited from class com.google.javascript.rhino.jstype.ObjectType
cast, createDelegateSuffix, defineDeclaredProperty, defineInferredProperty, defineSynthesizedProperty, findPropertyType, getDisplayName, getJSDocInfo, getNormalizedReferenceName, getOwnPropertyJSDocInfo, getOwnSlot, getParentScope, getPropertiesCount, getPropertyNames, getPropertyNode, getRootNode, getTemplateTypes, hasOwnProperty, hasProperty, isFunctionPrototypeType, isObject, isPropertyInExterns, isPropertyTypeDeclared, isPropertyTypeInferred, isUnknownType, setJSDocInfo, testForEquality
Methods inherited from class com.google.javascript.rhino.jstype.JSType
autobox, autoboxesTo, canCastTo, canTestForEqualityWith, canTestForShallowEqualityWith, clearResolved, collapseUnion, dereference, differsFrom, equals, forceResolve, getGreatestSubtype, getLeastSupertype, getRestrictedTypeGivenToBooleanOutcome, getTemplateTypeMap, getTypesUnderEquality, getTypesUnderInequality, getTypesUnderShallowEquality, getTypesUnderShallowInequality, hasAnyTemplateTypes, hasDisplayName, isAllType, isArrayType, isBooleanObjectType, isBooleanValueType, isCheckedUnknownType, isDateType, isDict, isEmptyType, isEnumElementType, isEnumType, isEquivalent, isEquivalentTo, isFunctionType, isGlobalThisType, isInvariant, isNominalConstructor, isNominalType, isNoResolvedType, isNullType, isNumber, isNumberObjectType, isNumberValueType, isRecordType, isRegexpType, isResolved, isString, isStringObjectType, isStringValueType, isStruct, isTemplateType, isTemplatizedType, isUnionType, isVoidType, matchesInt32Context, matchesUint32Context, resolve, restrictByNotNullOrUndefined, setValidator, toAnnotationString, toMaybeEnumElementType, toMaybeEnumType, toMaybeFunctionType, toMaybeTemplateType, toMaybeTemplateType, toMaybeTemplatizedType, toMaybeTemplatizedType, toMaybeUnionType, toObjectType, toString
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Method Details
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isNoObjectType
public boolean isNoObjectType()- Overrides:
isNoObjectType
in classNoObjectType
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isNoType
public boolean isNoType() -
isNullable
public boolean isNullable()Description copied from class:JSType
Tests whether this type is nullable.- Overrides:
isNullable
in classJSType
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isSubtype
Description copied from class:FunctionType
A function is a subtype of another if their call methods are related via subtyping andthis
is a subtype ofthat
with regard to the prototype chain.- Overrides:
isSubtype
in classNoObjectType
- Returns:
this <: that
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getPossibleToBooleanOutcomes
Description copied from class:JSType
Computes the set of possible outcomes of theToBoolean
predicate for this type. TheToBoolean
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} - Overrides:
getPossibleToBooleanOutcomes
in classObjectType
- Returns:
- the set of boolean literals for this type
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matchesNumberContext
public boolean matchesNumberContext()Description copied from class:JSType
This predicate is used to test whether a given type can appear in a numeric context, such as an operand of a multiply operator.- Overrides:
matchesNumberContext
in classNoObjectType
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matchesObjectContext
public boolean matchesObjectContext()Description copied from class:JSType
This predicate is used to test whether a given type can appear in anObject
context, such as the expression in a with statement. Most types we will encounter, except notablynull
, have at least the potential for converting toObject
. Host defined objects can get peculiar.- Overrides:
matchesObjectContext
in classNoObjectType
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matchesStringContext
public boolean matchesStringContext()Description copied from class:JSType
This predicate is used to test whether a given type can appear in aString
context, such as an operand of a string concat (+) operator. All types have at least the potential for converting toString
. When we add externally defined types, such as a browser OM, we may choose to add types that do not automatically convert toString
.- Overrides:
matchesStringContext
in classNoObjectType
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visit
Description copied from class:JSType
Visit this type with the given visitor.- Overrides:
visit
in classNoObjectType
- Returns:
- the value returned by the visitor
- See Also:
-
unboxesTo
Description copied from class:JSType
Turn an object type to its corresponding scalar type. -
hasReferenceName
public boolean hasReferenceName()Description copied from class:ObjectType
Returns true if the object is named.- Overrides:
hasReferenceName
in classObjectType
- Returns:
- true if the object is named, false if it is anonymous
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isNativeObjectType
public boolean isNativeObjectType()Whether this is a built-in object.- Overrides:
isNativeObjectType
in classObjectType
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getOwnerFunction
Description copied from class:ObjectType
Gets the owner of this if it's a function prototype.- Overrides:
getOwnerFunction
in classObjectType
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getCtorImplementedInterfaces
Description copied from class:ObjectType
Gets the interfaces implemented by the ctor associated with this type. Intended to be overridden by subclasses.- Overrides:
getCtorImplementedInterfaces
in classObjectType
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getCtorExtendedInterfaces
Description copied from class:ObjectType
Gets the interfaces extended by the interface associated with this type. Intended to be overridden by subclasses.- Overrides:
getCtorExtendedInterfaces
in classObjectType
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matchConstraint
Description copied from class:JSType
Modify this type so that it matches the specified type. This is useful for reverse type-inference, where we want to infer that an object literal matches its constraint (much like how the java compiler does reverse-inference to figure out generics).- Overrides:
matchConstraint
in classJSType
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matchRecordTypeConstraint
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