Datasheet

Chapter 1: Introduction to JavaScript
14
ECMAScript Support by Engine
ECMAScript is the Ecma International specification that describes the JavaScript language. Strictly
speaking, browsers implement ECMAScript, the standard, not JavaScript, a Sun trademark licensed by
Mozilla and the name of Mozilla ’ s engine.
There have been four revisions to the original ECMA 262 draft, all at different stages of adoption:
Edition Published Differences to the Previous Edition
1 June 1997 n/a
2 June 1998 Editorial changes to keep the specification fully aligned
with ISO/IEC 16262 international standard.
3 December 1999 Added regular expressions, better string handling, new
control statements, try/catch exception handling, tighter
definition of errors, formatting for numeric output and
other enhancements.
3.1 (Now 5) Work in progress AKA “ Harmony. ” More modest syntactic changes than
revision 4. Class - based inheritance.
4 Work in progress Multiple new concepts and language features. Has been
since superseded, oddly enough, by the newer v3.1.
ECMAScript Support corresponds to different Engine versions as follows:
ECMAScript Edition Mozilla JavaScript Edition Microsoft JScript Version
1st Edition 1.3 (Netscape 4.06 - 4.7x, October
1998)
3.0 (IE 4.0, Oct 1997)
2nd Edition 1.3 (Netscape 4.06 - 4.7x, October
1998)
3.0 (IE 4.0, Oct 1997)
3rd Edition 1.5 (Netscape 6) 5.5 (IE 5.5, July 2000)
3.1 Edition (Now 5.0 Edition) Unknown Possibly 5.9 (Predictive)
4.0 Edition 2.0 (In progress and in question) Probably never, unless 3.1
becomes 4.0
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