ES6 Unicode Identifiers

[getify]

The new Unicode "code point escape" form is also valid for identifiers, such as:

var \u{2B400} = 42;

As usual, @mathiasbynens has a bunch of great stuff about what makes a valid Unicode identifier in ES6 vs ES5, etc.

[marijnh]

The hard part here appears to be that we don't yet know how to distinguish >0xFFFF code points as being identifier characters.

[getify]

I believe the regex at the above link gives that answer definitively, right?

[marijnh]

So that means there are no code points above 0xffff that can be part of an identifier? (This is entirely possible, I just don't know)

[mathiasbynens]

New blog post that documents the differences between ES5 and ES6 identifiers, with examples: https://mathiasbynens.be/notes/javascript-identifiers-es6 It answers your question, @marijnh.

[marijnh]

Right, so that puts us in a bit of a bind -- including another giant regexp (even bigger than the old ones -- some 14k) in the library to handle obscure identifier names is not a very attractive idea. But not being able to properly identify ES6 identifiers is also a shame.

Attached patch solves the issue reported here. The ES6 identifier issue is now tracked in #215