ECMAScript for XML (E4X) is the standar

programming language A programming language is a system of notation for writing computer programs. Most programming languages are text-based formal languages, but they may also be graphical. They are a kind of computer language. The description of a programming ...

extension that adds native

XML Extensible Markup Language (XML) is a markup language and file format for storing, transmitting, and reconstructing arbitrary data. It defines a set of rules for encoding documents in a format that is both human-readable and machine-readable ...

support to

ECMAScript ECMAScript (; ES) is a JavaScript standard intended to ensure the interoperability of web pages across different browsers. It is standardized by Ecma International in the documenECMA-262 ECMAScript is commonly used for client-side scripting o ...

(which includes

ActionScript ActionScript is an object-oriented programming language originally developed by Macromedia Inc. (later acquired by Adobe). It is influenced by HyperTalk, the scripting language for HyperCard. It is now an implementation of ECMAScript (meaning ...

JavaScript JavaScript (), often abbreviated as JS, is a programming language that is one of the core technologies of the World Wide Web, alongside HTML and CSS. As of 2022, 98% of websites use JavaScript on the client side for webpage behavior, of ...

, and

JScript JScript is Microsoft's legacy dialect of the ECMAScript standard that is used in Microsoft's Internet Explorer 11 and older. JScript is implemented as an Active Scripting engine. This means that it can be "plugged in" to OLE Automation applic ...

). The goal is to provide an alternative to DOM interfaces that uses a simpler syntax for accessing XML documents. It also offers a new way of making XML visible. Before the release of E4X, XML was always accessed at an object level. E4X instead treats XML as a primitive (like characters, integers, and booleans). This implies faster access, better support, and acceptance as a building block (data structure) of a program. E4X is standardized by

Ecma International Ecma International () is a nonprofit standards organization for information and communication systems. It acquired its current name in 1994, when the European Computer Manufacturers Association (ECMA) changed its name to reflect the organization ...

in th
ECMA-357 standard
The first edition was published in June 2004, the second edition in December 2005. The E4X standard was deprecated by the Mozilla Foundation in 2014.

Browser support

E4X is supported by Mozilla's

Rhino A rhinoceros (; ; ), commonly abbreviated to rhino, is a member of any of the five extant species (or numerous extinct species) of odd-toed ungulates in the family Rhinocerotidae. (It can also refer to a member of any of the extinct species o ...

, used in

OpenOffice.org OpenOffice.org (OOo), commonly known as OpenOffice, is a discontinued open-source office suite. Active successor projects include LibreOffice (the most actively developed), Apache OpenOffice, Collabora Online (enterprise ready LibreOffice) a ...

and several other projects. It is also supported by

Tamarin The tamarins are squirrel-sized New World monkeys from the family Callitrichidae in the genus ''Saguinus''. They are the first offshoot in the Callitrichidae tree, and therefore are the sister group of a clade formed by the lion tamarins, Goe ...

, the JavaScript engine used in the

Flash Flash, flashes, or FLASH may refer to: Arts, entertainment, and media Fictional aliases * Flash (DC Comics character), several DC Comics superheroes with super speed: ** Flash (Barry Allen) ** Flash (Jay Garrick) ** Wally West, the first Kid F ...

virtual machine. It is not supported by other common engines like Nitro ( Safari), V8 ( Google Chrome), Carakan (

Opera Opera is a form of theatre in which music is a fundamental component and dramatic roles are taken by singers. Such a "work" (the literal translation of the Italian word "opera") is typically a collaboration between a composer and a libr ...

), Chakra (

Internet Explorer Internet Explorer (formerly Microsoft Internet Explorer and Windows Internet Explorer, commonly abbreviated IE or MSIE) is a series of graphical web browsers developed by Microsoft which was used in the Windows line of operating systems ( ...

and pre-Chromium

Edge Edge or EDGE may refer to: Technology Computing * Edge computing, a network load-balancing system * Edge device, an entry point to a computer network * Adobe Edge, a graphical development application * Microsoft Edge, a web browser developed ...

). E4X was also supported by

SpiderMonkey SpiderMonkey is the first JavaScript engine, written by Brendan Eich at Netscape Communications, later released as open source and currently maintained by the Mozilla Foundation. It is used in the Firefox web browser. History Eich "wrote ...

(used in

Firefox Mozilla Firefox, or simply Firefox, is a free and open-source web browser developed by the Mozilla Foundation and its subsidiary, the Mozilla Corporation. It uses the Gecko rendering engine to display web pages, which implements current ...

and

Thunderbird Thunderbird, thunder bird or thunderbirds may refer to: * Thunderbird (mythology), a legendary creature in certain North American indigenous peoples' history and culture * Ford Thunderbird, a car Birds * Dromornithidae, extinct flightless birds ...

), but has been removed. In Firefox 10, E4X syntax was no longer accepted in SpiderMonkey when ECMAScript 5 "strict mode" is enabled. According to

Brendan Eich Brendan Eich (; born July 4, 1961) is an American computer programmer and technology executive. He created the JavaScript programming language and co-founded the Mozilla project, the Mozilla Foundation, and the Mozilla Corporation. He served ...

, "This thus signals start of deprecation for E4X in SpiderMonkey." and "has been disabled by default for webpages (content) in Firefox 17, disabled by default for chrome in Firefox 20, and has been removed in Firefox 21"

Example

var sales = ; alert( sales.item.(@type

"carrot").@quantity ); alert( sales.@vendor ); for each( var price in sales..@price ) delete sales.item sales.item += ; sales.item.(@type

"oranges").@quantity = 4;

Implementations

The first implementation of E4X was designed by Terry Lucas and John Schneider and appeared in BEA's Weblogic Workshop 7.0 released in February 2002. BEA's implementation was based on

and released before the ECMAScript E4X spec was completed in June 2004. John Schneider wrote a
article
on the XML extensions in BEA's Workshop at the time. * E4X was implemented in

( Gecko's JavaScript engine) since version 1.6.0 until version 20, and is in

(Mozilla's other JavaScript engine written in Java instead of C) since version 1.6R1. * As Mozilla Firefox is based on Gecko, older versions could be used to run scripts using E4X. But this feature is deprecated since release 16 and removed in release 18. * Adobe's

3 scripting language fully supports E4X. Early previews of

3 were first made available in late 2005. Adobe officially released the language with

Flash Player Adobe Flash Player (known in Internet Explorer, Firefox, and Google Chrome as Shockwave Flash) is computer software for viewing multimedia contents, executing rich Internet applications, and streaming audio and video content created on the ...

9 on June 28, 2006. * E4X is available in Flash CS3,

Adobe AIR Adobe AIR (also known as Adobe Integrated Runtime and is codenamed Apollo) is a cross-platform runtime system currently developed by Harman International, in collaboration with Adobe Inc., for building desktop applications and mobile applicat ...

and

Adobe Flex Apache Flex, formerly Adobe Flex, is a software development kit (SDK) for the development and deployment of cross-platform rich web applications based on the Adobe Flash platform. Initially developed by Macromedia and then acquired by Adobe System ...

as they use ActionScript 3 as a scripting language. * E4X is also available in Adobe Acrobat and

Adobe Reader Adobe Acrobat is a family of application software and Web services developed by Adobe Inc. to view, create, manipulate, print and manage Portable Document Format (PDF) files. The family comprises Acrobat Reader (formerly Reader), Acrobat (former ...

versions 8.0 or higher (notably Forward Ported from SpiderMonkey version 17 and suggested may be dropped in the near future). * E4X is also available in Aptana's Jaxer Ajax application server which uses the Mozilla engine server-side. * Since the release of Alfresco Community Edition 2.9B, E4X is also available in this enterprise

document management system A document management system (DMS) is usually a computerized system used to store, share, track and manage files or documents. Some systems include history tracking where a log of the various versions created and modified by different users is r ...

. * E4X is available as part of

Mirth Connect Mirth Connect is a cross-platform interface engine used in the healthcare industry that enables the management of information using bi-directional sending of many types of messages. The primary use of this interface engine is in healthcare. On ...

's JavaScript message transformation engine.

Browser support

Example

Implementations

See also

References

External links