E4X added XML as a primitive data structure to allow for faster access[clarification needed] and better support within the language.
[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] E4X 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).