ECMAScript for XML (E4X) was an extension to ECMAScript (which includes ActionScript, JavaScript, and JScript) to add native support for XML.[1] The goal was to provide a simpler alternative to the DOM interface for accessing XML documents. E4X added XML as a primitive data structure to allow for faster access[clarification needed] and better support within the language.
E4X was standardized by Ecma International in the ECMA-357 standard. The first edition was published in June 2004 and the second edition in December 2005. However, the E4X standard was deprecated by the Mozilla Foundation in 2014,[2] and it was withdrawn by ISO/IEC in 2021.[1]
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.[citation needed] BEA's implementation was based on Rhino and released before the ECMAScript E4X spec was completed in June 2004.[citation needed]
Browser support
editE4X is supported by Mozilla's Rhino, as well as by Tamarin, the JavaScript engine used in the Flash virtual machine.[citation needed] However, it is not supported by other common engines like Nitro (Safari), V8 (Google Chrome), Carakan (Opera), and Chakra (Internet Explorer and pre-Chromium Edge).[3]
E4X was supported by SpiderMonkey (used in Firefox and Thunderbird). However, E4X was deprecated in Firefox 10[4] and eventually removed in Firefox 21.[5][clarification needed]
E4X was supported by the OpenOffice.org software suite.[citation needed]
Example
editvar sales = <sales vendor="John">
<item type="peas" price="4" quantity="6"/>
<item type="carrot" price="3" quantity="10"/>
<item type="chips" price="5" quantity="3"/>
</sales>;
alert( sales.item.(@type == "carrot").@quantity );
alert( sales.@vendor );
for each( var price in sales..@price ) {
alert( price );
}
delete sales.item[0];
sales.item += <item type="oranges" price="4"/>;
sales.item.(@type == "oranges").@quantity = 4;
See also
edit- JSX – an XML based markup specifically for DOM manipulation
References
edit- ^ a b "ISO/IEC 22537:2006 Information technology – ECMAscript for XML: E4X specification". International Organization for Standardization. Retrieved 2024-08-17.
- ^ "E4X – Archive of obsolete content – MDN". Mozilla. Archived from the original on 24 July 2014. Retrieved 10 September 2014.
- ^ "Issue 30975: Implement E4X Support for scripts and extensions". Retrieved 21 May 2012.
- ^ "Firefox 10 for developers". Mozilla. Archived from the original on 5 May 2012. Retrieved 21 May 2012.
- ^ "E4X". Mozilla. Archived from the original on 30 September 2013. Retrieved 12 February 2013.
External links
edit- ECMA-357 (withdrawn first edition, second edition)
- E4X at faqts.com (or via WayBack Machine)
- Slides from 2005 E4X Presentation by Brendan Eich, Mozilla Chief Architect
- E4X at Mozilla Developer Center Archived 2008-04-19 at the Wayback Machine
- Introducing E4X at xml.com: compares E4X and json
- Processing XML with E4X at Mozilla Developer Center
- E4X: Beginner to Advanced at Yahoo Developer Network