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ECMAScript is a Scripting Programming Language , standardized by Ecma International in the '''ECMA-262''' specification. The language is widely used on the Web , and is often referred to as ''' JavaScript ''' or ''' JScript ''', after the two primary implementations of the specification. HISTORY 2.0 was out, featuring support for JavaScript. Due to the de facto success of JavaScript as a client-side scripting language for web pages, Microsoft developed a compatible language known as JScript including new date functions that fixed JavaScript's Y2K non-compliant functions, which was included in Internet Explorer 3.0, released in August 1996. Microsoft submitted the JScript specification to Ecma International for standardization; the work on the specification, ECMA-262, began in November 1996. The first edition of ECMA-262 was adopted by the ECMA General Assembly of June 1997. ECMAScript is the name of the scripting language standardized in ECMA-262. Both JavaScript and JScript technologies aim to be compatible with ECMAScript, while providing additional features not described in the ECMA specification. The name "ECMAScript" was a compromise between the organizations involved in standardizing the language, especially Netscape and Microsoft. Brendan Eich, the creator of JavaScript, is on record as saying that "ECMAScript was always an unwanted trade name that sounds like a skin disease."https://mail.mozilla.org/private/es4-discuss/2006-October/000133.html VERSIONS There are three editions of ECMA-262 published, and the work on the fourth edition is in progress. In June 2004 Ecma International published ECMA-357 standard, defining an extension to ECMAScript, known as E4X (ECMAScript for XML). ECMA also defined a "Compact Profile" for ECMAScript -- known as ES-CP, or ECMA 327 -- which is designed for resource-constrained devices. Several of the dynamic features of ECMAScript (such as the "eval" function) are made optional, thus allowing the runtime to make more assumptions about the behaviour of programs and therefore make more performance trade-offs when running the code. The HD DVD standard is one place where the ECMAScript Compact Profile is used in favour of full ECMAScript in order to reduce processing and memory requirements on a device. DIALECTS ECMAScript is supported in many applications, especially Web Browser s, where it's commonly called JavaScript. Dialects typically include their own, different Standard Libraries , of which some are standardized separately – such as the W3C -specified DOM . Some implementations, such as ActionScript used in Flash, have a completely different set of libraries. This means that applications written in one dialect of ECMAScript will not likely work in another, unless they are designed to be compatible. Gecko 1.8.1 has partial support of E4X and a few other features, see [http://developer.mozilla.org/en/docs/New_in_JavaScript_1.7 New in JavaScript 1.7 . Microsoft asserts that JScript 8.0 supports "almost all of the features of the ECMAScript Edition 3 Language Specification" but does not list the unsupported features. In addition to supporting ECMA-262 edition 3, ActionScript 2 also included support of properties, methods, and mechanisms that were ''proposed'' in early draft specifications of as yet unseen versions of ECMAScript. It remains to be seen if ActionScript will stay ''in sync'' with future changes to the ECMAScript specifications. Adobe asserts it implements the preliminary edition 4 of ECMA-262 {Link without Title} As stated by OpenLaszlo, it partially implements edition 3 of ECMA-262 {Link without Title} The current Webkit binaries, as of April 2007, also implement at least part of the Javascript 1.6 extras The Mozilla implementations, ( SpiderMonkey in the C Programming Language and Rhino in the Java Programming Language ), are used in several Third-party programs, including the Yahoo! Widget Engine (Konfabulator) and the Macintosh system-level scripting language JavaScript OSA . Apple 's Safari uses JavaScriptCore which is based on the KDE KJS library. VERSION CORRESPONDENCE The following table is based on and [http://msdn.microsoft.com/library/default.asp?url=/library/en-us/script56/html/js56jsoriversioninformation.asp ; items on the same line are approximately the same language. FOURTH EDITION The ECMA-262 fourth edition is the first major update to ECMAScript since the third edition published in 1999. The new version of the language is backwards compatible with ECMAScript 3 while adding multiple new features, such as:
An export of ECMAScript 4 committee wiki is located at http://developer.mozilla.org/es4/ (note that the wiki is not exported regularly, so those documents are likely to be outdated). ECMAScript 4 intends to better support " Programming In The Large " and to let programmers sacrifice some of the script's ability to be dynamic for performance. For example, Tamarin — the virtual machine for ActionScript developed and open sourced by Adobe — has JIT compilation support for certain classes of scripts. SEE ALSO REFERENCES EXTERNAL LINKS
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