YUI Compressor is not ES5 complaint.

[grssam]

If your code is like

var foo = {
  delete : "asd"
};

then the compressor will give syntax errors, while the code is perfectly correct as per ES5, but is incorrect as per ES3.

Are there any plans to support ES5, or if you already are supporting ES5, then consider this as a new bug.

[tml]

This is because Rhino is not ES5 compliant (yet). As soon as a Rhino release comes out with ES5 support, I'll start migrating it in. Thanks for your input!

[grssam]

How hard it would be to migrate to node which is up to date in ES5 standards ?

[tml]

Well, node isn't a Javascript interpreter; we'd have to build it on v8. As for "how hard", it would be a complete rewrite - which probably doesn't make sense in the face of projects like mishoo/UglifyJS.

[grssam]

Rhino is kind of stalled right now. Not sure what are the plans on that front ..

[tml]

I don't know what their plans are, either, but if you look at the mozilla/rhino project, it's really not all THAT dead (compared to how close YUICompressor came!) A lot of ES5 is implemented in Rhino, the only really big issues I know of are strict mode, allowing reserved words as IdentifierNames (which is what this issue is raising), and a niggle about parseInt behaviour. If I find the bandwidth, I plan to address these myself eventually.

[grssam]

I just looked at the last commit time, it was 5 months ago.. so I assumed that it is stalled now :)

[tml]

I think that may be a bit premature; both Rhino and YUICompressor have had quiet periods lasting a lot more than 5 months...there was a lull of more than 18 months between YUICompressor 2.4.7 and 2.4.8 :)

[tml]

Tracking all versions of this issue on #47, closing the rest so that I only have one bug to keep track of for all the variants of the problem.