com.google.javascript.rhino.jstype

Class ArrowType

java.lang.Object

com.google.javascript.rhino.jstype.JSType

com.google.javascript.rhino.jstype.ArrowType

All Implemented Interfaces:

TypeI, java.io.Serializable

final class ArrowType
extends JSType

The arrow type is an internal type that models the functional arrow type seen in typical functional programming languages. It is used solely for separating the management of the arrow type from the complex FunctionType that models JavaScript's notion of functions.

Nested Class Summary

Nested classes/interfaces inherited from class com.google.javascript.rhino.jstype.JSType

JSType.EqCache, JSType.ImplCache, JSType.MatchStatus, JSType.TypePair

Field Summary

Fields

Modifier and Type	Field and Description
(package private) Node	parameters
(package private) JSType	returnType
(package private) boolean	returnTypeInferred
private static long	serialVersionUID

Fields inherited from class com.google.javascript.rhino.jstype.JSType

ALPHA, registry, templateTypeMap

Constructor Summary

Constructors

Constructor and Description
ArrowType(JSTypeRegistry registry, Node parameters, JSType returnType)
ArrowType(JSTypeRegistry registry, Node parameters, JSType returnType, boolean returnTypeInferred)

Method Summary

Modifier and Type	Method and Description
(package private) boolean	checkArrowEquivalenceHelper(ArrowType that, EquivalenceMethod eqMethod, JSType.EqCache eqCache)
JSType	getGreatestSubtype(JSType that) Gets the greatest subtype of this and that.
JSType	getLeastSupertype(JSType that) Gets the least supertype of this and that.
BooleanLiteralSet	getPossibleToBooleanOutcomes() Computes the set of possible outcomes of the ToBoolean predicate for this type.
boolean	hasAnyTemplateTypesInternal()
(package private) boolean	hasEqualParameters(ArrowType that, EquivalenceMethod eqMethod, JSType.EqCache eqCache)
int	hashCode()
private boolean	hasTemplatedParameterType()
(package private) boolean	hasUnknownParamsOrReturn()
boolean	isSubtype(JSType that) Checks whether this is a subtype of that.
protected boolean	isSubtype(JSType other, JSType.ImplCache implicitImplCache) checking isSubtype with structural interface matching
(package private) JSType	resolveInternal(ErrorReporter t, StaticTypedScope<JSType> scope)
TernaryValue	testForEquality(JSType that) Compares this and that.
(package private) java.lang.String	toStringHelper(boolean forAnnotations)
(package private) <T> T	visit(RelationshipVisitor<T> visitor, JSType that) Visit the types with the given visitor.
<T> T	visit(Visitor<T> visitor) Visit this type with the given visitor.

Methods inherited from class com.google.javascript.rhino.jstype.JSType

autobox, autoboxesTo, canBeCalled, canCastTo, canTestForEqualityWith, canTestForShallowEqualityWith, checkEquivalenceHelper, checkEquivalenceHelper, collapseUnion, dereference, differsFrom, equals, extendTemplateTypeMap, filterNoResolvedType, findPropertyType, getDisplayName, getGreatestSubtype, getJSDocInfo, getLeastSupertype, getNativeType, getRestrictedTypeGivenToBooleanOutcome, getTemplateTypeMap, getTypesUnderEquality, getTypesUnderInequality, getTypesUnderShallowEquality, getTypesUnderShallowInequality, hasAnyTemplateTypes, hasDisplayName, hasProperty, isAllType, isArrayType, isBooleanObjectType, isBooleanValueType, isBottom, isCheckedUnknownType, isConstructor, isDateType, isDict, isEmptyType, isEnumElementType, isEnumType, isEquivalent, isEquivalentTo, isEquivalentTo, isExemptFromTemplateTypeInvariance, isExplicitlyVoidable, isFunctionPrototypeType, isFunctionType, isGlobalThisType, isInstanceType, isInterface, isNamedType, isNominalConstructor, isNominalType, isNoObjectType, isNoResolvedType, isNoType, isNullable, isNullType, isNumber, isNumberObjectType, isNumberValueType, isObject, isOrdinaryFunction, isRecordType, isRegexpType, isResolved, isString, isStringObjectType, isStringValueType, isStruct, isStructuralInterface, isStructuralType, isSubtypeHelper, isSubtypeOf, isSubtypeWithoutStructuralTyping, isTemplateType, isTemplatizedType, isTheObjectType, isUnionType, isUnknownType, isVoidable, isVoidType, matchConstraint, matchesInt32Context, matchesNumberContext, matchesObjectContext, matchesStringContext, matchesUint32Context, resolve, restrictByNotNullOrUndefined, safeResolve, setResolvedTypeInternal, setValidator, testForEqualityHelper, toAnnotationString, toDebugHashCodeString, toMaybeEnumElementType, toMaybeEnumType, toMaybeFunctionType, toMaybeFunctionType, toMaybeNamedType, toMaybeObjectType, toMaybeRecordType, toMaybeTemplateType, toMaybeTemplatizedType, toMaybeUnionType, toNonNullAnnotationString, toObjectType, toString, unboxesTo

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

serialVersionUID

private static final long serialVersionUID

See Also:

Constant Field Values

parameters

final Node parameters

returnType

JSType returnType

returnTypeInferred

final boolean returnTypeInferred

Constructor Detail

ArrowType

ArrowType(JSTypeRegistry registry,
          Node parameters,
          JSType returnType)

ArrowType

ArrowType(JSTypeRegistry registry,
          Node parameters,
          JSType returnType,
          boolean returnTypeInferred)

Method Detail

isSubtype

public boolean isSubtype(JSType that)

Description copied from class: JSType

Checks whether this is a subtype of that.

Note this function also returns true if this type structurally matches the protocol define by that type (if that type is an interface function type) Subtyping rules:

• (unknown) — every type is a subtype of the Unknown type.
• (no) — the No type is a subtype of every type.
• (no-object) — the NoObject type is a subtype of every object type (i.e. subtypes of the Object type).
• (ref) — a type is a subtype of itself.
• (union-l) — A union type is a subtype of a type U if all the union type's constituents are a subtype of U. Formally
  (T1, …, Tn) <: U if and only Tk <: U for all k ∈ 1..n.
• (union-r) — A type U is a subtype of a union type if it is a subtype of one of the union type's constituents. Formally
  U <: (T1, …, Tn) if and only if U <: Tk for some index k.
• (objects) — an Object O1 is a subtype of an object O2 if it has more properties than O2 and all common properties are pairwise subtypes.

Overrides:

isSubtype in class JSType

Returns:

this <: that

isSubtype

protected boolean isSubtype(JSType other,
                            JSType.ImplCache implicitImplCache)

Description copied from class: JSType

checking isSubtype with structural interface matching

Overrides:

isSubtype in class JSType

implicitImplCache - a cache that records the checked or currently checking type pairs, for example, if previous checking found that constructor C is a subtype of interface I, then in the cache, table key <I,C> maps to IMPLEMENT status.

hasEqualParameters

boolean hasEqualParameters(ArrowType that,
                           EquivalenceMethod eqMethod,
                           JSType.EqCache eqCache)

Returns:

True if our parameter spec is equal to that's parameter spec.

checkArrowEquivalenceHelper

boolean checkArrowEquivalenceHelper(ArrowType that,
                                    EquivalenceMethod eqMethod,
                                    JSType.EqCache eqCache)

hashCode

public int hashCode()

Overrides:

hashCode in class JSType

getLeastSupertype

public JSType getLeastSupertype(JSType that)

Description copied from class: JSType

Gets the least supertype of this and that. The least supertype is the join (∨) or supremum of both types in the type lattice.

Examples:

• number ∨ * = *
• number ∨ Object = (number, Object)
• Number ∨ Object = Object

Overrides:

getLeastSupertype in class JSType

Returns:

this ∨ that

getGreatestSubtype

public JSType getGreatestSubtype(JSType that)

Description copied from class: JSType

Gets the greatest subtype of this and that. The greatest subtype is the meet (∧) or infimum of both types in the type lattice.

Examples

• Number ∧ Any = Any
• number ∧ Object = Any
• Number ∧ Object = Number

Overrides:

getGreatestSubtype in class JSType

Returns:

this ∨ that

testForEquality

public TernaryValue testForEquality(JSType that)

Description copied from class: JSType

Compares this and that.

Overrides:

testForEquality in class JSType

Returns:

• 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 values

visit

public <T> T visit(Visitor<T> visitor)

Description copied from class: JSType

Visit this type with the given visitor.

Specified by:

visit in class JSType

Returns:

the value returned by the visitor

See Also:

Visitor

visit

<T> T visit(RelationshipVisitor<T> visitor,
            JSType that)

Description copied from class: JSType

Visit the types with the given visitor.

Specified by:

visit in class JSType

Returns:

the value returned by the visitor

See Also:

RelationshipVisitor

getPossibleToBooleanOutcomes

public BooleanLiteralSet getPossibleToBooleanOutcomes()

Description copied from class: JSType

Computes the set of possible outcomes of the ToBoolean predicate for this type. The ToBoolean predicate is defined by the ECMA-262 standard, 3^rd 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}

Specified by:

getPossibleToBooleanOutcomes in class JSType

Returns:

the set of boolean literals for this type

resolveInternal

JSType resolveInternal(ErrorReporter t,
                       StaticTypedScope<JSType> scope)

Specified by:

resolveInternal in class JSType

See Also:

JSType.resolve(com.google.javascript.rhino.ErrorReporter, com.google.javascript.rhino.jstype.StaticTypedScope<com.google.javascript.rhino.jstype.JSType>)

hasUnknownParamsOrReturn

boolean hasUnknownParamsOrReturn()

toStringHelper

java.lang.String toStringHelper(boolean forAnnotations)

Specified by:

toStringHelper in class JSType

Parameters:

forAnnotations - Whether this is for use in code generator annotations. Otherwise, it's for warnings.

hasAnyTemplateTypesInternal

public boolean hasAnyTemplateTypesInternal()

Overrides:

hasAnyTemplateTypesInternal in class JSType

hasTemplatedParameterType

private boolean hasTemplatedParameterType()