Which Edition of ECMA-262 Does Google Apps Script

问题:

According to this thread from the old Google Group, Apps Script is based on ECMA-262 3rd Edition.

This would seem to be supported by the fact that auto-completion in the editor displays 3rd Edition array functions.

However the following code runs perfectly well, which casts doubt on the matter:

var array = [
  1,2,3,4,5
];

Logger.log("forEach:");
array.forEach(function (item,idx,arr) {
  Logger.log(item); 
});

Note the use of ECMA-262 5th Edition Array function forEach.

Would someone authoritative mind giving a definitive answer on why this is the case? And whether it's safe to rely on all 5th Edition features or a sub-set that have been implemented and seem to work?

回答1:

The current documentation (June 2013) says Apps Script provides a subset of ECMAScript 5 and is based on JavaScript 1.8.

Edit: Google has backtracked somewhat. As of Nov 2013, they are reporting that Apps Script is based on 1.6, with a smattering of 1.7 and 1.8.