Half a year ago Firefox dropped this non-standard addition (https://bugzilla.mozilla.org/show_bug.cgi?id=694360) and hasn’t seen any compatibility issues since.
Please align with Firefox and IE by removing this non-standard extension.
I’ve filed the same bug here:
* Opera/Carakan: https://bugs.opera.com/browse/DSK-369398
* Chrome/V8: http://code.google.com/p/v8/issues/detail?id=2222
See also: bug 42471.
(In reply to comment #3)
> See also: bug 42471.
Note that bug 42471 deals with IdentifierNames, while this bug (90678) is about Identifiers. Identifiers are IdentifierNames that are not reserved words.
See also: https://bugs.ecmascript.org/show_bug.cgi?id=277
FWIW, https://bugs.ecmascript.org/show_bug.cgi?id=277 is accepted, and Allen says he will make it clear (in ES6) that escaped reserved words are not allowed. The same goes for escaped regular expression flags.
Now would be a good time to drop this non-standard behavior that is apparently not a backwards compatibility concern.
Confirmed: ES6 drops the “escaped reserved words as identifiers” compatibility measure.
This will be fixed in v8: https://code.google.com/p/v8/issues/detail?id=2222#c4
SpiderMonkey already has ES6-compliant behavior: https://bugzilla.mozilla.org/show_bug.cgi?id=744784
What is the status of this? It is security significant for systems that pre-filter or translate code in order to enforce restrictions.