ECMAScript Harmony: New Life for JavaScript

One by one, the core standards that define the Web are getting a new lease on life. First, the W3C rebooted its development of HTML by abandoning its single-minded focus on XHTML and embracing the work of the WHAT-WG’s HTML 5 draft as a new beginning. Now, at a meeting in Oslo at the end of July, the long-divided standards body responsible for the JavaScript language has managed to find new unity through compromise.

The standard that describes JavaScript is called ECMAScript (because "JavaScript" is a trademark owned by Sun Microsystems). The last full update to ECMAScript, ECMA-262 3rd Edition, was published in 1999. In the over eight years since its publication, progress of JavaScript as a web standard has barely budged.

The lack of change to ECMAScript in that time has not been due to the language’s maturity. ECMA-262 3rd Edition has widely-recognized issues that real-world browsers have had to work around for years, so there has been plenty of need for a 4th Edition. In the absence of one, browser makers have had to reverse-engineer each other’s implementations in order to decide how to deal with the holes in the spec—pretty much the worst-case scenario for all concerned.