ECMAScript 2015 Language Specification

Introduction
1 Scope
2 Conformance
3 Normative references
4 Overview
- 4.1 Web Scripting
- 4.2 ECMAScript Overview
  - 4.2.1 Objects
  - 4.2.2 The Strict Variant of ECMAScript
- 4.3 Terms and definitions
  - 4.3.1 type
  - 4.3.2 primitive value
  - 4.3.3 object
  - 4.3.4 constructor
  - 4.3.5 prototype
  - 4.3.6 ordinary object
  - 4.3.7 exotic object
  - 4.3.8 standard object
  - 4.3.9 built-in object
  - 4.3.10 undefined value
  - 4.3.11 Undefined type
  - 4.3.12 null value
  - 4.3.13 Null type
  - 4.3.14 Boolean value
  - 4.3.15 Boolean type
  - 4.3.16 Boolean object
  - 4.3.17 String value
  - 4.3.18 String type
  - 4.3.19 String object
  - 4.3.20 Number value
  - 4.3.21 Number type
  - 4.3.22 Number object
  - 4.3.23 Infinity
  - 4.3.24 NaN
  - 4.3.25 Symbol value
  - 4.3.26 Symbol type
  - 4.3.27 Symbol object
  - 4.3.28 function
  - 4.3.29 built-in function
  - 4.3.30 property
  - 4.3.31 method
  - 4.3.32 built-in method
  - 4.3.33 attribute
  - 4.3.34 own property
  - 4.3.35 inherited property
- 4.4 Organization of This Specification
5 Notational Conventions
- 5.1 Syntactic and Lexical Grammars
  - 5.1.1 Context-Free Grammars
  - 5.1.2 The Lexical and RegExp Grammars
  - 5.1.3 The Numeric String Grammar
  - 5.1.4 The Syntactic Grammar
  - 5.1.5 Grammar Notation
- 5.2 Algorithm Conventions
- 5.3 Static Semantic Rules
6 ECMAScript Data Types and Values
- 6.1 ECMAScript Language Types
  - 6.1.1 The Undefined Type
  - 6.1.2 The Null Type
  - 6.1.3 The Boolean Type
  - 6.1.4 The String Type
  - 6.1.5 The Symbol Type
  - 6.1.6 The Number Type
  - 6.1.7 The Object Type
- 6.2 ECMAScript Specification Types
  - 6.2.1 The List and Record Specification Type
  - 6.2.2 The Completion Record Specification Type
  - 6.2.3 The Reference Specification Type
  - 6.2.4 The Property Descriptor Specification Type
  - 6.2.5 The Lexical Environment and Environment Record Specification Types
  - 6.2.6 Data Blocks
7 Abstract Operations
- 7.1 Type Conversion
  - 7.1.1 ToPrimitive ( input [, PreferredType] )
  - 7.1.2 ToBoolean ( argument )
  - 7.1.3 ToNumber ( argument )
  - 7.1.4 ToInteger ( argument )
  - 7.1.5 ToInt32 ( argument )
  - 7.1.6 ToUint32 ( argument )
  - 7.1.7 ToInt16 ( argument )
  - 7.1.8 ToUint16 ( argument )
  - 7.1.9 ToInt8 ( argument )
  - 7.1.10 ToUint8 ( argument )
  - 7.1.11 ToUint8Clamp ( argument )
  - 7.1.12 ToString ( argument )
  - 7.1.13 ToObject ( argument )
  - 7.1.14 ToPropertyKey ( argument )
  - 7.1.15 ToLength ( argument )
  - 7.1.16 CanonicalNumericIndexString ( argument )
- 7.2 Testing and Comparison Operations
  - 7.2.1 RequireObjectCoercible ( argument )
  - 7.2.2 IsArray ( argument )
  - 7.2.3 IsCallable ( argument )
  - 7.2.4 IsConstructor ( argument )
  - 7.2.5 IsExtensible (O)
  - 7.2.6 IsInteger ( argument )
  - 7.2.7 IsPropertyKey ( argument )
  - 7.2.8 IsRegExp ( argument )
  - 7.2.9 SameValue(x, y)
  - 7.2.10 SameValueZero(x, y)
  - 7.2.11 Abstract Relational Comparison
  - 7.2.12 Abstract Equality Comparison
  - 7.2.13 Strict Equality Comparison
- 7.3 Operations on Objects
  - 7.3.1 Get (O, P)
  - 7.3.2 GetV (V, P)
  - 7.3.3 Set (O, P, V, Throw)
  - 7.3.4 CreateDataProperty (O, P, V)
  - 7.3.5 CreateMethodProperty (O, P, V)
  - 7.3.6 CreateDataPropertyOrThrow (O, P, V)
  - 7.3.7 DefinePropertyOrThrow (O, P, desc)
  - 7.3.8 DeletePropertyOrThrow (O, P)
  - 7.3.9 GetMethod (O, P)
  - 7.3.10 HasProperty (O, P)
  - 7.3.11 HasOwnProperty (O, P)
  - 7.3.12 Call(F, V, [argumentsList])
  - 7.3.13 Construct (F, [argumentsList], [newTarget])
  - 7.3.14 SetIntegrityLevel (O, level)
  - 7.3.15 TestIntegrityLevel (O, level)
  - 7.3.16 CreateArrayFromList (elements)
  - 7.3.17 CreateListFromArrayLike (obj [, elementTypes] )
  - 7.3.18 Invoke(O,P, [argumentsList])
  - 7.3.19 OrdinaryHasInstance (C, O)
  - 7.3.20 SpeciesConstructor ( O, defaultConstructor )
  - 7.3.21 EnumerableOwnNames (O)
  - 7.3.22 GetFunctionRealm ( obj )
- 7.4 Operations on Iterator Objects
  - 7.4.1 GetIterator ( obj, method )
  - 7.4.2 IteratorNext ( iterator, value )
  - 7.4.3 IteratorComplete ( iterResult )
  - 7.4.4 IteratorValue ( iterResult )
  - 7.4.5 IteratorStep ( iterator )
  - 7.4.6 IteratorClose( iterator, completion )
  - 7.4.7 CreateIterResultObject ( value, done )
  - 7.4.8 CreateListIterator ( list )
8 Executable Code and Execution Contexts
- 8.1 Lexical Environments
  - 8.1.1 Environment Records
  - 8.1.2 Lexical Environment Operations
- 8.2 Code Realms
  - 8.2.1 CreateRealm ( )
  - 8.2.2 CreateIntrinsics ( realmRec )
  - 8.2.3 SetRealmGlobalObject ( realmRec, globalObj )
  - 8.2.4 SetDefaultGlobalBindings ( realmRec )
- 8.3 Execution Contexts
  - 8.3.1 ResolveBinding ( name, [env] )
  - 8.3.2 GetThisEnvironment ( )
  - 8.3.3 ResolveThisBinding ( )
  - 8.3.4 GetNewTarget ( )
  - 8.3.5 GetGlobalObject ( )
- 8.4 Jobs and Job Queues
  - 8.4.1 EnqueueJob (queueName, job, arguments)
  - 8.4.2 NextJob result
- 8.5 ECMAScript Initialization()
  - 8.5.1 InitializeHostDefinedRealm ( realm )
9 Ordinary and Exotic Objects Behaviours
- 9.1 Ordinary Object Internal Methods and Internal Slots
  - 9.1.1 [[GetPrototypeOf]] ( )
  - 9.1.2 [[SetPrototypeOf]] (V)
  - 9.1.3 [[IsExtensible]] ( )
  - 9.1.4 [[PreventExtensions]] ( )
  - 9.1.5 [[GetOwnProperty]] (P)
  - 9.1.6 [[DefineOwnProperty]] (P, Desc)
  - 9.1.7 [[HasProperty]](P)
  - 9.1.8 [[Get]] (P, Receiver)
  - 9.1.9 [[Set]] ( P, V, Receiver)
  - 9.1.10 [[Delete]] (P)
  - 9.1.11 [[Enumerate]] ()
  - 9.1.12 [[OwnPropertyKeys]] ( )
  - 9.1.13 ObjectCreate(proto, internalSlotsList)
  - 9.1.14 OrdinaryCreateFromConstructor ( constructor, intrinsicDefaultProto, internalSlotsList )
  - 9.1.15 GetPrototypeFromConstructor ( constructor, intrinsicDefaultProto )
- 9.2 ECMAScript Function Objects
  - 9.2.1 [[Call]] ( thisArgument, argumentsList)
  - 9.2.2 [[Construct]] ( argumentsList, newTarget)
  - 9.2.3 FunctionAllocate (functionPrototype, strict [,functionKind] )
  - 9.2.4 FunctionInitialize (F, kind, ParameterList, Body, Scope)
  - 9.2.5 FunctionCreate (kind, ParameterList, Body, Scope, Strict, prototype)
  - 9.2.6 GeneratorFunctionCreate (kind, ParameterList, Body, Scope, Strict)
  - 9.2.7 AddRestrictedFunctionProperties ( F, realm )
  - 9.2.8 MakeConstructor (F, writablePrototype, prototype)
  - 9.2.9 MakeClassConstructor ( F)
  - 9.2.10 MakeMethod ( F, homeObject)
  - 9.2.11 SetFunctionName (F, name, prefix)
  - 9.2.12 FunctionDeclarationInstantiation(func, argumentsList)
- 9.3 Built-in Function Objects
  - 9.3.1 [[Call]] ( thisArgument, argumentsList)
  - 9.3.2 [[Construct]] (argumentsList, newTarget)
  - 9.3.3 CreateBuiltinFunction(realm, steps, prototype, internalSlotsList)
- 9.4 Built-in Exotic Object Internal Methods and Slots
  - 9.4.1 Bound Function Exotic Objects
  - 9.4.2 Array Exotic Objects
  - 9.4.3 String Exotic Objects
  - 9.4.4 Arguments Exotic Objects
  - 9.4.5 Integer Indexed Exotic Objects
  - 9.4.6 Module Namespace Exotic Objects
- 9.5 Proxy Object Internal Methods and Internal Slots
  - 9.5.1 [[GetPrototypeOf]] ( )
  - 9.5.2 [[SetPrototypeOf]] (V)
  - 9.5.3 [[IsExtensible]] ( )
  - 9.5.4 [[PreventExtensions]] ( )
  - 9.5.5 [[GetOwnProperty]] (P)
  - 9.5.6 [[DefineOwnProperty]] (P, Desc)
  - 9.5.7 [[HasProperty]] (P)
  - 9.5.8 [[Get]] (P, Receiver)
  - 9.5.9 [[Set]] ( P, V, Receiver)
  - 9.5.10 [[Delete]] (P)
  - 9.5.11 [[Enumerate]] ()
  - 9.5.12 [[OwnPropertyKeys]] ( )
  - 9.5.13 [[Call]] (thisArgument, argumentsList)
  - 9.5.14 [[Construct]] ( argumentsList, newTarget)
  - 9.5.15 ProxyCreate(target, handler)
10 ECMAScript Language: Source Code
- 10.1 Source Text
  - 10.1.1 Static Semantics: UTF16Encoding ( cp )
  - 10.1.2 Static Semantics: UTF16Decode( lead, trail )
- 10.2 Types of Source Code
  - 10.2.1 Strict Mode Code
  - 10.2.2 Non-ECMAScript Functions
11 ECMAScript Language: Lexical Grammar
- 11.1 Unicode Format-Control Characters
- 11.2 White Space
- 11.3 Line Terminators
- 11.4 Comments
- 11.5 Tokens
- 11.6 Names and Keywords
  - 11.6.1 Identifier Names
  - 11.6.2 Reserved Words
- 11.7 Punctuators
- 11.8 Literals
  - 11.8.1 Null Literals
  - 11.8.2 Boolean Literals
  - 11.8.3 Numeric Literals
  - 11.8.4 String Literals
  - 11.8.5 Regular Expression Literals
  - 11.8.6 Template Literal Lexical Components
- 11.9 Automatic Semicolon Insertion
  - 11.9.1 Rules of Automatic Semicolon Insertion
  - 11.9.2 Examples of Automatic Semicolon Insertion
12 ECMAScript Language: Expressions
- 12.1 Identifiers
  - 12.1.1 Static Semantics: Early Errors
  - 12.1.2 Static Semantics: BoundNames
  - 12.1.3 Static Semantics: IsValidSimpleAssignmentTarget
  - 12.1.4 Static Semantics: StringValue
  - 12.1.5 Runtime Semantics: BindingInitialization
  - 12.1.6 Runtime Semantics: Evaluation
- 12.2 Primary Expression
  - 12.2.1 Semantics
  - 12.2.2 The this Keyword
  - 12.2.3 Identifier Reference
  - 12.2.4 Literals
  - 12.2.5 Array Initializer
  - 12.2.6 Object Initializer
  - 12.2.7 Function Defining Expressions
  - 12.2.8 Regular Expression Literals
  - 12.2.9 Template Literals
  - 12.2.10 The Grouping Operator
- 12.3 Left-Hand-Side Expressions
  - 12.3.1 Static Semantics
  - 12.3.2 Property Accessors
  - 12.3.3 The new Operator
  - 12.3.4 Function Calls
  - 12.3.5 The super Keyword
  - 12.3.6 Argument Lists
  - 12.3.7 Tagged Templates
  - 12.3.8 Meta Properties
- 12.4 Postfix Expressions
  - 12.4.1 Static Semantics: Early Errors
  - 12.4.2 Static Semantics: IsFunctionDefinition
  - 12.4.3 Static Semantics: IsValidSimpleAssignmentTarget
  - 12.4.4 Postfix Increment Operator
  - 12.4.5 Postfix Decrement Operator
- 12.5 Unary Operators
  - 12.5.1 Static Semantics: Early Errors
  - 12.5.2 Static Semantics: IsFunctionDefinition
  - 12.5.3 Static Semantics: IsValidSimpleAssignmentTarget
  - 12.5.4 The delete Operator
  - 12.5.5 The void Operator
  - 12.5.6 The typeof Operator
  - 12.5.7 Prefix Increment Operator
  - 12.5.8 Prefix Decrement Operator
  - 12.5.9 Unary + Operator
  - 12.5.10 Unary - Operator
  - 12.5.11 Bitwise NOT Operator ( ~ )
  - 12.5.12 Logical NOT Operator ( ! )
- 12.6 Multiplicative Operators
  - 12.6.1 Static Semantics: IsFunctionDefinition
  - 12.6.2 Static Semantics: IsValidSimpleAssignmentTarget
  - 12.6.3 Runtime Semantics: Evaluation
- 12.7 Additive Operators
  - 12.7.1 Static Semantics: IsFunctionDefinition
  - 12.7.2 Static Semantics: IsValidSimpleAssignmentTarget
  - 12.7.3 The Addition operator ( + )
  - 12.7.4 The Subtraction Operator ( - )
  - 12.7.5 Applying the Additive Operators to Numbers
- 12.8 Bitwise Shift Operators
  - 12.8.1 Static Semantics: IsFunctionDefinition
  - 12.8.2 Static Semantics: IsValidSimpleAssignmentTarget
  - 12.8.3 The Left Shift Operator ( << )
  - 12.8.4 The Signed Right Shift Operator ( >> )
  - 12.8.5 The Unsigned Right Shift Operator ( >>> )
- 12.9 Relational Operators
  - 12.9.1 Static Semantics: IsFunctionDefinition
  - 12.9.2 Static Semantics: IsValidSimpleAssignmentTarget
  - 12.9.3 Runtime Semantics: Evaluation
  - 12.9.4 Runtime Semantics: InstanceofOperator(O, C)
- 12.10 Equality Operators
  - 12.10.1 Static Semantics: IsFunctionDefinition
  - 12.10.2 Static Semantics: IsValidSimpleAssignmentTarget
  - 12.10.3 Runtime Semantics: Evaluation
- 12.11 Binary Bitwise Operators
  - 12.11.1 Static Semantics: IsFunctionDefinition
  - 12.11.2 Static Semantics: IsValidSimpleAssignmentTarget
  - 12.11.3 Runtime Semantics: Evaluation
- 12.12 Binary Logical Operators
  - 12.12.1 Static Semantics: IsFunctionDefinition
  - 12.12.2 Static Semantics: IsValidSimpleAssignmentTarget
  - 12.12.3 Runtime Semantics: Evaluation
- 12.13 Conditional Operator ( ? : )
  - 12.13.1 Static Semantics: IsFunctionDefinition
  - 12.13.2 Static Semantics: IsValidSimpleAssignmentTarget
  - 12.13.3 Runtime Semantics: Evaluation
- 12.14 Assignment Operators
  - 12.14.1 Static Semantics: Early Errors
  - 12.14.2 Static Semantics: IsFunctionDefinition
  - 12.14.3 Static Semantics: IsValidSimpleAssignmentTarget
  - 12.14.4 Runtime Semantics: Evaluation
  - 12.14.5 Destructuring Assignment
- 12.15 Comma Operator ( , )
  - 12.15.1 Static Semantics: IsFunctionDefinition
  - 12.15.2 Static Semantics: IsValidSimpleAssignmentTarget
  - 12.15.3 Runtime Semantics: Evaluation
13 ECMAScript Language: Statements and Declarations
- 13.1 Statement Semantics
  - 13.1.1 Static Semantics: ContainsDuplicateLabels
  - 13.1.2 Static Semantics: ContainsUndefinedBreakTarget
  - 13.1.3 Static Semantics: ContainsUndefinedContinueTarget
  - 13.1.4 Static Semantics: DeclarationPart
  - 13.1.5 Static Semantics: VarDeclaredNames
  - 13.1.6 Static Semantics: VarScopedDeclarations
  - 13.1.7 Runtime Semantics: LabelledEvaluation
  - 13.1.8 Runtime Semantics: Evaluation
- 13.2 Block
  - 13.2.1 Static Semantics: Early Errors
  - 13.2.2 Static Semantics: ContainsDuplicateLabels
  - 13.2.3 Static Semantics: ContainsUndefinedBreakTarget
  - 13.2.4 Static Semantics: ContainsUndefinedContinueTarget
  - 13.2.5 Static Semantics: LexicallyDeclaredNames
  - 13.2.6 Static Semantics: LexicallyScopedDeclarations
  - 13.2.7 Static Semantics: TopLevelLexicallyDeclaredNames
  - 13.2.8 Static Semantics: TopLevelLexicallyScopedDeclarations
  - 13.2.9 Static Semantics: TopLevelVarDeclaredNames
  - 13.2.10 Static Semantics: TopLevelVarScopedDeclarations
  - 13.2.11 Static Semantics: VarDeclaredNames
  - 13.2.12 Static Semantics: VarScopedDeclarations
  - 13.2.13 Runtime Semantics: Evaluation
  - 13.2.14 Runtime Semantics: BlockDeclarationInstantiation( code, env )
- 13.3 Declarations and the Variable Statement
  - 13.3.1 Let and Const Declarations
  - 13.3.2 Variable Statement
  - 13.3.3 Destructuring Binding Patterns
- 13.4 Empty Statement
  - 13.4.1 Runtime Semantics: Evaluation
- 13.5 Expression Statement
  - 13.5.1 Runtime Semantics: Evaluation
- 13.6 The if Statement
  - 13.6.1 Static Semantics: Early Errors
  - 13.6.2 Static Semantics: ContainsDuplicateLabels
  - 13.6.3 Static Semantics: ContainsUndefinedBreakTarget
  - 13.6.4 Static Semantics: ContainsUndefinedContinueTarget
  - 13.6.5 Static Semantics: VarDeclaredNames
  - 13.6.6 Static Semantics: VarScopedDeclarations
  - 13.6.7 Runtime Semantics: Evaluation
- 13.7 Iteration Statements
  - 13.7.1 Semantics
  - 13.7.2 The do-while Statement
  - 13.7.3 The while Statement
  - 13.7.4 The for Statement
  - 13.7.5 The for-in and for-of Statements
- 13.8 The continue Statement
  - 13.8.1 Static Semantics: Early Errors
  - 13.8.2 Static Semantics: ContainsUndefinedContinueTarget
  - 13.8.3 Runtime Semantics: Evaluation
- 13.9 The break Statement
  - 13.9.1 Static Semantics: Early Errors
  - 13.9.2 Static Semantics: ContainsUndefinedBreakTarget
  - 13.9.3 Runtime Semantics: Evaluation
- 13.10 The return Statement
  - 13.10.1 Runtime Semantics: Evaluation
- 13.11 The with Statement
  - 13.11.1 Static Semantics: Early Errors
  - 13.11.2 Static Semantics: ContainsDuplicateLabels
  - 13.11.3 Static Semantics: ContainsUndefinedBreakTarget
  - 13.11.4 Static Semantics: ContainsUndefinedContinueTarget
  - 13.11.5 Static Semantics: VarDeclaredNames
  - 13.11.6 Static Semantics: VarScopedDeclarations
  - 13.11.7 Runtime Semantics: Evaluation
- 13.12 The switch Statement
  - 13.12.1 Static Semantics: Early Errors
  - 13.12.2 Static Semantics: ContainsDuplicateLabels
  - 13.12.3 Static Semantics: ContainsUndefinedBreakTarget
  - 13.12.4 Static Semantics: ContainsUndefinedContinueTarget
  - 13.12.5 Static Semantics: LexicallyDeclaredNames
  - 13.12.6 Static Semantics: LexicallyScopedDeclarations
  - 13.12.7 Static Semantics: VarDeclaredNames
  - 13.12.8 Static Semantics: VarScopedDeclarations
  - 13.12.9 Runtime Semantics: CaseBlockEvaluation
  - 13.12.10 Runtime Semantics: CaseSelectorEvaluation
  - 13.12.11 Runtime Semantics: Evaluation
- 13.13 Labelled Statements
  - 13.13.1 Static Semantics: Early Errors
  - 13.13.2 Static Semantics: ContainsDuplicateLabels
  - 13.13.3 Static Semantics: ContainsUndefinedBreakTarget
  - 13.13.4 Static Semantics: ContainsUndefinedContinueTarget
  - 13.13.5 Static Semantics: IsLabelledFunction ( stmt )
  - 13.13.6 Static Semantics: LexicallyDeclaredNames
  - 13.13.7 Static Semantics: LexicallyScopedDeclarations
  - 13.13.8 Static Semantics: TopLevelLexicallyDeclaredNames
  - 13.13.9 Static Semantics: TopLevelLexicallyScopedDeclarations
  - 13.13.10 Static Semantics: TopLevelVarDeclaredNames
  - 13.13.11 Static Semantics: TopLevelVarScopedDeclarations
  - 13.13.12 Static Semantics: VarDeclaredNames
  - 13.13.13 Static Semantics: VarScopedDeclarations
  - 13.13.14 Runtime Semantics: LabelledEvaluation
  - 13.13.15 Runtime Semantics: Evaluation
- 13.14 The throw Statement
  - 13.14.1 Runtime Semantics: Evaluation
- 13.15 The try Statement
  - 13.15.1 Static Semantics: Early Errors
  - 13.15.2 Static Semantics: ContainsDuplicateLabels
  - 13.15.3 Static Semantics: ContainsUndefinedBreakTarget
  - 13.15.4 Static Semantics: ContainsUndefinedContinueTarget
  - 13.15.5 Static Semantics: VarDeclaredNames
  - 13.15.6 Static Semantics: VarScopedDeclarations
  - 13.15.7 Runtime Semantics: CatchClauseEvaluation
  - 13.15.8 Runtime Semantics: Evaluation
- 13.16 The debugger statement
  - 13.16.1 Runtime Semantics: Evaluation
14 ECMAScript Language: Functions and Classes
- 14.1 Function Definitions
  - 14.1.1 Directive Prologues and the Use Strict Directive
  - 14.1.2 Static Semantics: Early Errors
  - 14.1.3 Static Semantics: BoundNames
  - 14.1.4 Static Semantics: Contains
  - 14.1.5 Static Semantics: ContainsExpression
  - 14.1.6 Static Semantics: ExpectedArgumentCount
  - 14.1.7 Static Semantics: HasInitializer
  - 14.1.8 Static Semantics: HasName
  - 14.1.9 Static Semantics: IsAnonymousFunctionDefinition ( production )
  - 14.1.10 Static Semantics: IsConstantDeclaration
  - 14.1.11 Static Semantics: IsFunctionDefinition
  - 14.1.12 Static Semantics: IsSimpleParameterList
  - 14.1.13 Static Semantics: LexicallyDeclaredNames
  - 14.1.14 Static Semantics: LexicallyScopedDeclarations
  - 14.1.15 Static Semantics: VarDeclaredNames
  - 14.1.16 Static Semantics: VarScopedDeclarations
  - 14.1.17 Runtime Semantics: EvaluateBody
  - 14.1.18 Runtime Semantics: IteratorBindingInitialization
  - 14.1.19 Runtime Semantics: InstantiateFunctionObject
  - 14.1.20 Runtime Semantics: Evaluation
- 14.2 Arrow Function Definitions
  - 14.2.1 Static Semantics: Early Errors
  - 14.2.2 Static Semantics: BoundNames
  - 14.2.3 Static Semantics: Contains
  - 14.2.4 Static Semantics: ContainsExpression
  - 14.2.5 Static Semantics: ExpectedArgumentCount
  - 14.2.6 Static Semantics: HasInitializer
  - 14.2.7 Static Semantics: HasName
  - 14.2.8 Static Semantics: IsSimpleParameterList
  - 14.2.9 Static Semantics: CoveredFormalsList
  - 14.2.10 Static Semantics: LexicallyDeclaredNames
  - 14.2.11 Static Semantics: LexicallyScopedDeclarations
  - 14.2.12 Static Semantics: VarDeclaredNames
  - 14.2.13 Static Semantics: VarScopedDeclarations
  - 14.2.14 Runtime Semantics: IteratorBindingInitialization
  - 14.2.15 Runtime Semantics: EvaluateBody
  - 14.2.16 Runtime Semantics: Evaluation
- 14.3 Method Definitions
  - 14.3.1 Static Semantics: Early Errors
  - 14.3.2 Static Semantics: ComputedPropertyContains
  - 14.3.3 Static Semantics: ExpectedArgumentCount
  - 14.3.4 Static Semantics: HasComputedPropertyKey
  - 14.3.5 Static Semantics: HasDirectSuper
  - 14.3.6 Static Semantics: PropName
  - 14.3.7 Static Semantics: SpecialMethod
  - 14.3.8 Runtime Semantics: DefineMethod
  - 14.3.9 Runtime Semantics: PropertyDefinitionEvaluation
- 14.4 Generator Function Definitions
  - 14.4.1 Static Semantics: Early Errors
  - 14.4.2 Static Semantics: BoundNames
  - 14.4.3 Static Semantics: ComputedPropertyContains
  - 14.4.4 Static Semantics: Contains
  - 14.4.5 Static Semantics: HasComputedPropertyKey
  - 14.4.6 Static Semantics: HasDirectSuper
  - 14.4.7 Static Semantics: HasName
  - 14.4.8 Static Semantics: IsConstantDeclaration
  - 14.4.9 Static Semantics: IsFunctionDefinition
  - 14.4.10 Static Semantics: PropName
  - 14.4.11 Runtime Semantics: EvaluateBody
  - 14.4.12 Runtime Semantics: InstantiateFunctionObject
  - 14.4.13 Runtime Semantics: PropertyDefinitionEvaluation
  - 14.4.14 Runtime Semantics: Evaluation
- 14.5 Class Definitions
  - 14.5.1 Static Semantics: Early Errors
  - 14.5.2 Static Semantics: BoundNames
  - 14.5.3 Static Semantics: ConstructorMethod
  - 14.5.4 Static Semantics: Contains
  - 14.5.5 Static Semantics: ComputedPropertyContains
  - 14.5.6 Static Semantics: HasName
  - 14.5.7 Static Semantics: IsConstantDeclaration
  - 14.5.8 Static Semantics: IsFunctionDefinition
  - 14.5.9 Static Semantics: IsStatic
  - 14.5.10 Static Semantics: NonConstructorMethodDefinitions
  - 14.5.11 Static Semantics: PrototypePropertyNameList
  - 14.5.12 Static Semantics: PropName
  - 14.5.13 Static Semantics: StaticPropertyNameList
  - 14.5.14 Runtime Semantics: ClassDefinitionEvaluation
  - 14.5.15 Runtime Semantics: BindingClassDeclarationEvaluation
  - 14.5.16 Runtime Semantics: Evaluation
- 14.6 Tail Position Calls
  - 14.6.1 Static Semantics: IsInTailPosition(nonterminal)
  - 14.6.2 Static Semantics: HasProductionInTailPosition
  - 14.6.3 Runtime Semantics: PrepareForTailCall ( )
15 ECMAScript Language: Scripts and Modules
- 15.1 Scripts
  - 15.1.1 Static Semantics: Early Errors
  - 15.1.2 Static Semantics: IsStrict
  - 15.1.3 Static Semantics: LexicallyDeclaredNames
  - 15.1.4 Static Semantics: LexicallyScopedDeclarations
  - 15.1.5 Static Semantics: VarDeclaredNames
  - 15.1.6 Static Semantics: VarScopedDeclarations
  - 15.1.7 Runtime Semantics: ScriptEvaluation
  - 15.1.8 Runtime Semantics: GlobalDeclarationInstantiation (script, env)
  - 15.1.9 Runtime Semantics: ScriptEvaluationJob ( sourceText )
- 15.2 Modules
  - 15.2.1 Module Semantics
  - 15.2.2 Imports
  - 15.2.3 Exports
16 Error Handling and Language Extensions
- 16.1 Forbidden Extensions
17 ECMAScript Standard Built-in Objects
18 The Global Object
- 18.1 Value Properties of the Global Object
  - 18.1.1 Infinity
  - 18.1.2 NaN
  - 18.1.3 undefined
- 18.2 Function Properties of the Global Object
  - 18.2.1 eval (x)
  - 18.2.2 isFinite (number)
  - 18.2.3 isNaN (number)
  - 18.2.4 parseFloat (string)
  - 18.2.5 parseInt (string , radix)
  - 18.2.6 URI Handling Functions
- 18.3 Constructor Properties of the Global Object
  - 18.3.1 Array ( . . . )
  - 18.3.2 ArrayBuffer ( . . . )
  - 18.3.3 Boolean ( . . . )
  - 18.3.4 DataView ( . . . )
  - 18.3.5 Date ( . . . )
  - 18.3.6 Error ( . . . )
  - 18.3.7 EvalError ( . . . )
  - 18.3.8 Float32Array ( . . . )
  - 18.3.9 Float64Array ( . . . )
  - 18.3.10 Function ( . . . )
  - 18.3.11 Int8Array ( . . . )
  - 18.3.12 Int16Array ( . . . )
  - 18.3.13 Int32Array ( . . . )
  - 18.3.14 Map ( . . . )
  - 18.3.15 Number ( . . . )
  - 18.3.16 Object ( . . . )
  - 18.3.17 Proxy ( . . . )
  - 18.3.18 Promise ( . . . )
  - 18.3.19 RangeError ( . . . )
  - 18.3.20 ReferenceError ( . . . )
  - 18.3.21 RegExp ( . . . )
  - 18.3.22 Set ( . . . )
  - 18.3.23 String ( . . . )
  - 18.3.24 Symbol ( . . . )
  - 18.3.25 SyntaxError ( . . . )
  - 18.3.26 TypeError ( . . . )
  - 18.3.27 Uint8Array ( . . . )
  - 18.3.28 Uint8ClampedArray ( . . . )
  - 18.3.29 Uint16Array ( . . . )
  - 18.3.30 Uint32Array ( . . . )
  - 18.3.31 URIError ( . . . )
  - 18.3.32 WeakMap ( . . . )
  - 18.3.33 WeakSet ( . . . )
- 18.4 Other Properties of the Global Object
  - 18.4.1 JSON
  - 18.4.2 Math
  - 18.4.3 Reflect
19 Fundamental Objects
- 19.1 Object Objects
  - 19.1.1 The Object Constructor
  - 19.1.2 Properties of the Object Constructor
  - 19.1.3 Properties of the Object Prototype Object
  - 19.1.4 Properties of Object Instances
- 19.2 Function Objects
  - 19.2.1 The Function Constructor
  - 19.2.2 Properties of the Function Constructor
  - 19.2.3 Properties of the Function Prototype Object
  - 19.2.4 Function Instances
- 19.3 Boolean Objects
  - 19.3.1 The Boolean Constructor
  - 19.3.2 Properties of the Boolean Constructor
  - 19.3.3 Properties of the Boolean Prototype Object
  - 19.3.4 Properties of Boolean Instances
- 19.4 Symbol Objects
  - 19.4.1 The Symbol Constructor
  - 19.4.2 Properties of the Symbol Constructor
  - 19.4.3 Properties of the Symbol Prototype Object
  - 19.4.4 Properties of Symbol Instances
- 19.5 Error Objects
  - 19.5.1 The Error Constructor
  - 19.5.2 Properties of the Error Constructor
  - 19.5.3 Properties of the Error Prototype Object
  - 19.5.4 Properties of Error Instances
  - 19.5.5 Native Error Types Used in This Standard
  - 19.5.6 NativeError Object Structure
20 Numbers and Dates
- 20.1 Number Objects
  - 20.1.1 The Number Constructor
  - 20.1.2 Properties of the Number Constructor
  - 20.1.3 Properties of the Number Prototype Object
  - 20.1.4 Properties of Number Instances
- 20.2 The Math Object
  - 20.2.1 Value Properties of the Math Object
  - 20.2.2 Function Properties of the Math Object
- 20.3 Date Objects
  - 20.3.1 Overview of Date Objects and Definitions of Abstract Operations
  - 20.3.2 The Date Constructor
  - 20.3.3 Properties of the Date Constructor
  - 20.3.4 Properties of the Date Prototype Object
  - 20.3.5 Properties of Date Instances
21 Text Processing
- 21.1 String Objects
  - 21.1.1 The String Constructor
  - 21.1.2 Properties of the String Constructor
  - 21.1.3 Properties of the String Prototype Object
  - 21.1.4 Properties of String Instances
  - 21.1.5 String Iterator Objects
- 21.2 RegExp (Regular Expression) Objects
  - 21.2.1 Patterns
  - 21.2.2 Pattern Semantics
  - 21.2.3 The RegExp Constructor
  - 21.2.4 Properties of the RegExp Constructor
  - 21.2.5 Properties of the RegExp Prototype Object
  - 21.2.6 Properties of RegExp Instances
22 Indexed Collections
- 22.1 Array Objects
  - 22.1.1 The Array Constructor
  - 22.1.2 Properties of the Array Constructor
  - 22.1.3 Properties of the Array Prototype Object
  - 22.1.4 Properties of Array Instances
  - 22.1.5 Array Iterator Objects
- 22.2 TypedArray Objects
  - 22.2.1 The %TypedArray% Intrinsic Object
  - 22.2.2 Properties of the %TypedArray% Intrinsic Object
  - 22.2.3 Properties of the %TypedArrayPrototype% Object
  - 22.2.4 The TypedArray Constructors
  - 22.2.5 Properties of the TypedArray Constructors
  - 22.2.6 Properties of TypedArray Prototype Objects
  - 22.2.7 Properties of TypedArray Instances
23 Keyed Collection
- 23.1 Map Objects
  - 23.1.1 The Map Constructor
  - 23.1.2 Properties of the Map Constructor
  - 23.1.3 Properties of the Map Prototype Object
  - 23.1.4 Properties of Map Instances
  - 23.1.5 Map Iterator Objects
- 23.2 Set Objects
  - 23.2.1 The Set Constructor
  - 23.2.2 Properties of the Set Constructor
  - 23.2.3 Properties of the Set Prototype Object
  - 23.2.4 Properties of Set Instances
  - 23.2.5 Set Iterator Objects
- 23.3 WeakMap Objects
  - 23.3.1 The WeakMap Constructor
  - 23.3.2 Properties of the WeakMap Constructor
  - 23.3.3 Properties of the WeakMap Prototype Object
  - 23.3.4 Properties of WeakMap Instances
- 23.4 WeakSet Objects
  - 23.4.1 The WeakSet Constructor
  - 23.4.2 Properties of the WeakSet Constructor
  - 23.4.3 Properties of the WeakSet Prototype Object
  - 23.4.4 Properties of WeakSet Instances
24 Structured Data
- 24.1 ArrayBuffer Objects
  - 24.1.1 Abstract Operations For ArrayBuffer Objects
  - 24.1.2 The ArrayBuffer Constructor
  - 24.1.3 Properties of the ArrayBuffer Constructor
  - 24.1.4 Properties of the ArrayBuffer Prototype Object
  - 24.1.5 Properties of the ArrayBuffer Instances
- 24.2 DataView Objects
  - 24.2.1 Abstract Operations For DataView Objects
  - 24.2.2 The DataView Constructor
  - 24.2.3 Properties of the DataView Constructor
  - 24.2.4 Properties of the DataView Prototype Object
  - 24.2.5 Properties of DataView Instances
- 24.3 The JSON Object
  - 24.3.1 JSON.parse ( text [ , reviver ] )
  - 24.3.2 JSON.stringify ( value [ , replacer [ , space ] ] )
  - 24.3.3 JSON [ @@toStringTag ]
25 Control Abstraction Objects
- 25.1 Iteration
  - 25.1.1 Common Iteration Interfaces
  - 25.1.2 The %IteratorPrototype% Object
- 25.2 GeneratorFunction Objects
  - 25.2.1 The GeneratorFunction Constructor
  - 25.2.2 Properties of the GeneratorFunction Constructor
  - 25.2.3 Properties of the GeneratorFunction Prototype Object
  - 25.2.4 GeneratorFunction Instances
- 25.3 Generator Objects
  - 25.3.1 Properties of Generator Prototype
  - 25.3.2 Properties of Generator Instances
  - 25.3.3 Generator Abstract Operations
- 25.4 Promise Objects
  - 25.4.1 Promise Abstract Operations
  - 25.4.2 Promise Jobs
  - 25.4.3 The Promise Constructor
  - 25.4.4 Properties of the Promise Constructor
  - 25.4.5 Properties of the Promise Prototype Object
  - 25.4.6 Properties of Promise Instances
26 Reflection
- 26.1 The Reflect Object
  - 26.1.1 Reflect.apply ( target, thisArgument, argumentsList )
  - 26.1.2 Reflect.construct ( target, argumentsList [, newTarget] )
  - 26.1.3 Reflect.defineProperty ( target, propertyKey, attributes )
  - 26.1.4 Reflect.deleteProperty ( target, propertyKey )
  - 26.1.5 Reflect.enumerate ( target )
  - 26.1.6 Reflect.get ( target, propertyKey [ , receiver ])
  - 26.1.7 Reflect.getOwnPropertyDescriptor ( target, propertyKey )
  - 26.1.8 Reflect.getPrototypeOf ( target )
  - 26.1.9 Reflect.has ( target, propertyKey )
  - 26.1.10 Reflect.isExtensible (target)
  - 26.1.11 Reflect.ownKeys ( target )
  - 26.1.12 Reflect.preventExtensions ( target )
  - 26.1.13 Reflect.set ( target, propertyKey, V [ , receiver ] )
  - 26.1.14 Reflect.setPrototypeOf ( target, proto )
- 26.2 Proxy Objects
  - 26.2.1 The Proxy Constructor
  - 26.2.2 Properties of the Proxy Constructor
- 26.3 Module Namespace Objects
  - 26.3.1 @@toStringTag
  - 26.3.2 [ @@iterator ] ( )
Annex A (informative) Grammar Summary
- A.1 Lexical Grammar
- A.2 Expressions
- A.3 Statements
- A.4 Functions and Classes
- A.5 Scripts and Modules
- A.6 Number Conversions
- A.7 Universal Resource Identifier Character Classes
- A.8 Regular Expressions
Annex B (normative) Additional ECMAScript Features for Web Browsers
- B.1 Additional Syntax
  - B.1.1 Numeric Literals
  - B.1.2 String Literals
  - B.1.3 HTML-like Comments
  - B.1.4 Regular Expressions Patterns
- B.2 Additional Built-in Properties
  - B.2.1 Additional Properties of the Global Object
  - B.2.2 Additional Properties of the Object.prototype Object
  - B.2.3 Additional Properties of the String.prototype Object
  - B.2.4 Additional Properties of the Date.prototype Object
  - B.2.5 Additional Properties of the RegExp.prototype Object
- B.3 Other Additional Features
  - B.3.1 __proto__ Property Names in Object Initializers
  - B.3.2 Labelled Function Declarations
  - B.3.3 Block-Level Function Declarations Web Legacy Compatibility Semantics
  - B.3.4 FunctionDeclarations in IfStatement Statement Clauses
  - B.3.5 VariableStatements in Catch blocks
Annex C (informative) The Strict Mode of ECMAScript
Annex D (informative) Corrections and Clarifications in ECMAScript 2015 with Possible Compatibility Impact
Annex E (informative) Additions and Changes That Introduce Incompatibilities with Prior Editions
Bibliography

Standard ECMA-262 6^th Edition / June 2015, ECMAScript^® 2015 Language Specification

Contents

Standard ECMA-262 6th Edition / June 2015, ECMAScript® 2015 Language Specification

Contents

Standard ECMA-262 6^th Edition / June 2015, ECMAScript^® 2015 Language Specification