ISO/IEC 16262:2011

Information technology - Programming languages, their environments and system software interfaces - ECMAScript language specification

ISO/IEC 16262:2011 defines the ECMAScript scripting language.

Technologies de l'information — Langages de programmation, leurs environnements et interfaces de logiciel système — Spécification du langage ECMAscript

General Information

• Status: Withdrawn
• Publication Date: 24-May-2011
• Withdrawal Date: 24-May-2011
• ICS: 35.060 - Languages used in information technology
• Technical Committee: ISO/IEC JTC 1/SC 22 - Programming languages, their environments and system software interfaces
• Drafting Committee: ISO/IEC JTC 1/SC 22 - Programming languages, their environments and system software interfaces
• Current Stage: 9599 - Withdrawal of International Standard
• Start Date: 09-May-2018
• Completion Date: 30-Oct-2025

Relations

• Revised: ISO/IEC 22275:2018 - Information technology - Programming languages, their environments, and system software interfaces - ECMAScript® Specification Suite
• Effective Date: 18-Feb-2017
• Revises: ISO/IEC 16262:2002 - Information technology - ECMAScript language specification
• Effective Date: 19-Dec-2009

Standards Content (Sample)

INTERNATIONAL ISO/IEC
STANDARD 16262
Third edition
2011-06.15
Information technology — Programming
languages, their environments and
system software interfaces —
ECMAScript language specification
Technologies de l'information — Langages de programmation, leurs
environnements et interfaces de logiciel système — Spécification du
langage ECMAscript
Reference number
©
ISO/IEC 2011
©  ISO/IEC 2011
All rights reserved. Unless otherwise specif ied, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocop ying and microfilm, w ithout permission in writing from either ISO at the address below or
ISO's member body in the country of the requester.
ISO copyright office
Case postale 56  CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail [e-mail]
Web www.iso.org
Published in Switzerland
ii © ISO/IEC 2011 – All rights reserved

Contents Page
Foreword .viii
Introduction.ix
1 Scope.1
2 Conformance.1
3 Normative references.1
4 Overview.1
4.1 Web Scripting.2
4.2 Language Overview.2
4.2.1 Objects.3
4.2.2 The Strict Variant of ECMAScript .4
4.3 Terms and definitions.4
5 Notational Conventions.8
5.1 Syntactic and Lexical Grammars.8
5.1.1 Context-Free Grammars.8
5.1.2 The Lexical and RegExp Grammars .8
5.1.3 The Numeric String Grammar .8
5.1.4 The Syntactic Grammar.8
5.1.5 The JSON Grammar.9
5.1.6 Grammar Notation.9
5.2 Algorithm Conventions.12
6 Source Text.13
7 Lexical Conventions.14
7.1 Unicode Format-Control Characters.14
7.2 White Space.15
7.3 Line Terminators.15
7.4 Comments.16
7.5 Tokens.17
7.6 Identifier Names and Identifiers.17
7.6.1 Reserved Words.18
7.7 Punctuators.19
7.8 Literals.20
7.8.1 Null Literals.20
7.8.2 Boolean Literals.20
7.8.3 Numeric Literals.20
7.8.4 String Literals.22
7.8.5 Regular Expression Literals.25
7.9 Automatic Semicolon Insertion.26
7.9.1 Rules of Automatic Semicolon Insertion .26
7.9.2 Examples of Automatic Semicolon Insertion.27
8 Types.28
8.1 The Undefined Type.28
8.2 The Null Type .28
8.3 The Boolean Type.29
8.4 The String Type.29
8.5 The Number Type.29
8.6 The Object Type .30
8.6.1 Property Attributes.30
8.6.2 Object Internal Properties and Methods .31
© ISO/IEC 2011 — All rights reserved iii

8.7 The Reference Specification Type.35
8.7.1 GetValue (V).35
8.7.2 PutValue (V, W).36
8.8 The List Specification Type.36
8.9 The Completion Specification Type.36
8.10 The Property Descriptor and Property Identifier Specification Types.37
8.10.1 IsAccessorDescriptor ( Desc ) .37
8.10.2 IsDataDescriptor ( Desc ).37
8.10.3 IsGenericDescriptor ( Desc ).37
8.10.4 FromPropertyDescriptor ( Desc ).38
8.10.5 ToPropertyDescriptor ( Obj ).38
8.11 The Lexical Environment and Environment Record Specification Types .39
8.12 Algorithms for Object Internal Methods.39
8.12.1 [[GetOwnProperty]] (P).39
8.12.2 [[GetProperty]] (P).39
8.12.3 [[Get]] (P).39
8.12.4 [[CanPut]] (P).39
8.12.5 [[Put]] ( P, V, Throw ).40
8.12.6 [[HasProperty]] (P).40
8.12.7 [[Delete]] (P, Throw).41
8.12.8 [[DefaultValue]] (hint).41
8.12.9 [[DefineOwnProperty]] (P, Desc, Throw) .41
9 Type Conversion and Testing .43
9.1 ToPrimitive.43
9.2 ToBoolean.43
9.3 ToNumber.43
9.3.1 ToNumber Applied to the String Type.44
9.4 ToInteger.46
9.5 ToInt32: (Signed 32 Bit Integer) .47
9.6 ToUint32: (Unsigned 32 Bit Integer) .47
9.7 ToUint16: (Unsigned 16 Bit Integer) .47
9.8 ToString.48
9.8.1 ToString Applied to the Number Type.48
9.9 ToObject.49
9.10 CheckObjectCoercible.49
9.11 IsCallable.49
9.12 The SameValue Algorithm.50
10 Executable Code and Execution Contexts.50
10.1 Types of Executable Code.50
10.1.1 Strict Mode Code.51
10.2 Lexical Environments.51
10.2.1 Environment Records.51
10.2.2 Lexical Environment Operations .56
10.2.3 The Global Environment.56
10.3 Execution Contexts.56
10.3.1 Identifier Resolution.57
10.4 Establishing an Execution Context .57
10.4.1 Entering Global Code .58
10.4.2 Entering Eval Code .58
10.4.3 Entering Function Code .58
10.5 Declaration Binding Instantiation.59
10.6 Arguments Object.60
11 Expressions.63
11.1 Primary Expressions.63
11.1.1 The this Keyword.63
11.1.2 Identifier Reference.63
11.1.3 Literal Reference.63
11.1.4 Array Initialiser.63
iv © ISO/IEC 2011 — All rights reserved

11.1.5 Object Initialiser.65
11.1.6 The Grouping Operator .67
11.2 Left-Hand-Side Expressions.67
11.2.1 Property Accessors.67
11.2.2 The new Operator.68
11.2.3 Function Calls.68
11.2.4 Argument Lists.69
11.2.5 Function Expressions.69
11.3 Postfix Expressions.69
11.3.1 Postfix Increment Operator.70
11.3.2 Postfix Decrement Operator.70
11.4 Unary Operators.70
11.4.1 The delete Operator.70
11.4.2 The void Operator.71
11.4.3 The typeof Operator.71
11.4.4 Prefix Increment Operator.71
11.4.5 Prefix Decrement Operator .72
11.4.6 Unary + Operator .72
11.4.7 Unary - Operator .72
11.4.8 Bitwise NOT Operator ( ~ ) .72
11.4.9 Logical NOT Operator ( ! ) .73
11.5 Multiplicative Operators.73
11.5.1 Applying the * Operator .73
11.5.2 Applying the / Operator .74
11.5.3 Applying the % Operator .74
11.6 Additive Operators.75
11.6.1 The Addition operator ( + ) .75
11.6.2 The Subtraction Operator ( - ) .75
11.6.3 Applying the Additive Operators to Numbers.75
11.7 Bitwise Shift Operators.76
11.7.1 The Left Shift Operator ( << ) .76
11.7.2 The Signed Right Shift Operator ( >> ) .76
11.7.3 The Unsigned Right Shift Operator ( >>> ).77
11.8 Relational Operators.77
11.8.1 The Less-than Operator ( < ) .77
11.8.2 The Greater-than Operator ( > ).78
11.8.3 The Less-than-or-equal Operator ( <= ).78
11.8.4 The Greater-than-or-equal Operator ( >= ) .78
11.8.5 The Abstract Relational Comparison Algorithm.78
11.8.6 The instanceof operator .79
11.8.7 The in operator.79
11.9 Equality Operators.80
11.9.1 The Equals Operator ( == ) .80
11.9.2 The Does-not-equals Operator ( != ) .80
11.9.3 The Abstract Equality Comparison Algorithm.80
11.9.4 The Strict Equals Operator ( === ).81
11.9.5 The Strict Does-not-equal Operator ( !== ).81
11.9.6 The Strict Equality Comparison Algorithm .82
11.10 Binary Bitwise Operators .82
11.11 Binary Logical Operators .83
11.12 Conditional Operator ( ? : ) .84
11.13 Assignment Operators.84
11.13.1 Simple Assignment ( = ) .85
11.13.2 Compound Assignment ( op= ).85
11.14 Comma Operator ( , ).85
12 Statements.86
12.1 Block.86
© ISO/IEC 2011 — All rights reserved v

12.2 Variable Statement.87
12.2.1 Strict Mode Restrictions.88
12.3 Empty Statement.88
12.4 Expression Statement.89
12.5 The if Statement .89
12.6 Iteration Statements.89
12.6.1 The do-while Statement .90
12.6.2 The while Statement.90
12.6.3 The for Statement.90
12.6.4 The for-in Statement .91
12.7 The continue Statement .92
12.8 The break Statement.93
12.9 The return Statement .93
12.10 The with Statement.93
12.10.1 Strict Mode Restrictions.94
12.11 The switch Statement .94
12.12 Labelled Statements.96
12.13 The throw Statement.96
12.14 The try Statement.96
12.14.1 Strict Mode Restrictions.97
12.15 The debugger statement.97
13 Function Definition.98
13.1 Strict Mode Restrictions.99
13.2 Creating Function Objects .99
13.2.1 [[Call]].100
13.2.2 [[Construct]].100
13.2.3 The [[ThrowTypeError]] Function Object .100
14 Program.101
14.1 Directive Prologues and the Use Strict Directive .101
15 Standard Built-in ECMAScript Objects.102
15.1 The Global Object.103
15.1.1 Value Properties of the Global Object .103
15.1.2 Function Properties of the Global Object.104
15.1.3 URI Handling Function Properties.105
15.1.4 Constructor Properties of the Global Object .110
15.1.5 Other Properties of the Global Object .111
15.2 Object Objects.111
15.2.1 The Object Constructor Called as a Function.111
15.2.2 The Object Constructor.112
15.2.3 Properties of the Object Constructor .112
15.2.4 Properties of the Object Prototype Object.115
15.2.5 Properties of Object Instances .117
15.3 Function Objects.117
15.3.1 The Function Constructor Called as a Function.117
15.3.2 The Function Constructor.117
15.3.3 Properties of the Function Constructor .118
15.3.4 Properties of the Function Prototype Object.118
15.3.5 Properties of Function Instances.121
15.4 Array Objects.122
15.4.1 The Array Constructor Called as a Function .122
15.4.2 The Array Constructor.123
15.4.3 Properties of the Array Constructor.123
15.4.4 Properties of the Array Prototype Object.124
15.4.5 Properties of Array Instances .140
15.5 String Objects.141
15.5.1 The String Constructor Called as a Function .141
15.5.2 The String Constructor.142
vi © ISO/IEC 2011 — All rights reserved

15.5.3 Properties of the String Constructor.142
15.5.4 Properties of the String Prototype Object.142
15.5.5 Properties of String Instances .152
15.6 Boolean Objects.152
15.6.1 The Boolean Constructor Called as a Function.152
15.6.2 The Boolean Constructor.152
15.6.3 Properties of the Boolean Constructor .153
15.6.4 Properties of the Boolean Prototype Object.153
15.6.5 Properties of Boolean Instances .154
15.7 Number Objects.154
15.7.1 The Number Constructor Called as a Function .154
15.7.2 The Number Constructor.154
15.7.3 Properties of the Number Constructor.154
15.7.4 Properties of the Number Prototype Object.155
15.7.5 Properties of Number Instances .159
15.8 The Math Object.159
15.8.1 Value Properties of the Math Object.159
15.8.2 Function Properties of the Math Object .161
15.9 Date Objects.165
15.9.1 Overview of Date Objects and Definitions of Abstract Operators.165
15.9.2 The Date Constructor Called as a Function.171
15.9.3 The Date Constructor .171
15.9.4 Properties of the Date Constructor.172
15.9.5 Properties of the Date Prototype Object .173
15.9.6 Properties of Date Instances.181
15.10 RegExp (Regular Expression) Objects.181
15.10.1 Patterns .181
15.10.2 Pattern Semantics.183
15.10.3 The RegExp Constructor Called as a Function .195
15.10.4 The RegExp Constructor.195
15.10.5 Properties of the RegExp Constructor.196
15.10.6 Properties of the RegExp Prototype Object.196
15.10.7 Properties of RegExp Instances .198
15.11 Error Objects.198
15.11.1 The Error Constructor Called as a Function.199
15.11.2 The Error Constructor .199
15.11.3 Properties of the Error Constructor.199
15.11.4 Properties of the Error Prototype Object .199
15.11.5 Properties of Error Instances.200
15.11.6 Native Error Types Used in This Standard.200
15.11.7 NativeError Object Structure.201
15.12 The JSON Object.203
15.12.1 The JSON Grammar.203
15.12.2 parse ( text [ , reviver ] ).204
15.12.3 stringify ( value [ , replacer [ , space ] ] ).206
16 Errors.209
Annex A (informative) Grammar Summary .211
Annex B (informative) Compatibility.230
Annex C (informative) The Strict Mode of ECMAScript.234
rd nd
Annex D (informative) Corrections and Clarifications in the 3 Edition with Possible 2 Edition
Compatibility Impact.236
rd
Annex E (informative) Additions and Changes in the 3 Edition that Introduce Incompatibilities
nd
with the 2 Edition .237
Bibliography.240

© ISO/IEC 2011 — All rights reserved vii

Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are members of
ISO or IEC participate in the development of International Standards through technical committees
established by the respective organization to deal with particular fields of technical activity. ISO and IEC
technical committees collaborate in fields of mutual interest. Other international organizations, governmental
and non-governmental, in liaison with ISO and IEC, also take part in the work. In the field of information
technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of the joint technical committee is to prepare International Standards. Draft International
Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as
an International Standard requires approval by at least 75 % of the national bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights.
ISO/IEC 16262 was prepared by Ecma International (as ECMA-262) and was adopted, under a special “fast-
track procedure”, by Joint Technical Committee ISO/IEC JTC 1, Information technology, in parallel with its
approval by national bodies of ISO and IEC.
This third edition cancels and replaces the second edition (ISO/IEC 16262:2002), which has been technically
revised.
viii © ISO/IEC 2011 — All rights reserved

Introduction
This International Standard is based on several originating technologies, the most well-known being
JavaScript (Netscape) and JScript (Microsoft). The lang uage was invented by Bren dan Eich at
Netscape and first a ppeared in that company’s Navigator 2.0 browser. It has appeared in all
subsequent browsers from Netscape and in all browsers from Microsoft starting with Internet Explorer
3.0.
The development of this Internation al Standard started in November 1996. The first editi on of this
International Standard was adopted by the Ecma General Assembly of June 1997.
That International Standard was submitted to IS O/IEC JTC 1 for ad option under the fast-track
procedure, and approved as ISO/IEC 16262, first edition, in April 1998.
The second edition of this International Standard introduced powerful regular expressions, better string
handling, new control statements, try/catch exception handling, tighter definition of errors, formattin g
for numeric output and minor changes in anticipation of forthcoming internationalization facilities and
future language growth. The second edition of the ECMAScript standa
...