Adobe Systems appears to have been wrong footed and Microsoft left crowing on JavaScript’s evolution, following a decision by the ECMA.

After several months of wrangling, ECMA technical committee (TC) 39 - responsible for JavaScript standardization - has agreed to abandon plans for an ambitious new standard dubbed ECMAScript (ES) 4 and concentrate on evolving the current standard ES 3.1 under the new name ES Harmony. The move is seen by some as a blow to Adobe, which had based ActionScript - the language that underpins its Flash platform - on ES4.

The conflict within TC 39 spilled into the public domain in October 2007 when Microsoft's Internet Explorer platform architect Chris Wilson criticized ES 4 for trying to introduce too many changes.

Wilson's criticism was strongly countered by Mozilla chief architect Brendan Eich, a senior member of TC 39. Eich accused Wilson of "spreading falsehoods" about ES 4 and playing political games because Microsoft saw ES 4 as "a competitive threat". He also noted that Microsoft has neglected to upgrade its JavaScript compliance in Internet Explorer until it had to.

While Microsoft congratulates itself over its apparent victory, Adobe is putting on a brave face. In response to questions over the future of ActionScript, Adobe community expert Dan Smith indicated (see comments) that it would track the new ES Harmony specifications. But he also said that key features from ES4 that have now been abandoned will remain. These include namespaces, packages and classes.

Adobe does not appear to be against cutting back on ES 4 features in principle. Lars Hansen, Adobe's representative on TC 39, proposed cutting back on ES 4 features back in February 2008.®