Is \u006eew a valid Identifier?

Caitlin Potter caitpotter88 at
Mon Nov 9 18:39:54 UTC 2015

`var x = “\u006eew”;` has a different meaning in the grammar, as compared with `var \u006eew = x;`.

Since you can’t declare `var new`, there is no good reason why you should be able to declare `var \u006eew;`.

On a similar note, allowing escaped keywords to have the same semantic meaning as the keywords (which would break allowing them as Identifiers anyways), is a problem. A naive user-input sanitizer could cause a page to be defaced, or worse, arbitrary code evaluated on a web-server, in the case of an input like `(f\u{75}nction() { /* somethingSneaky */ })();`.

Given that, these seem like perfectly good reasons not to allow it in the language.

> On Nov 9, 2015, at 1:25 PM, Coroutines <coroutines at> wrote:
> On Mon, Nov 9, 2015 at 10:10 AM, Isiah Meadows <isiahmeadows at> wrote:
>> Is there a reason why escapes like that in the title shouldn't evaluate to
>> keywords? To be honest, it's bad style, but I don't get how it would be
>> breaking the Web.
> This.  I do not understand this either.
> If you were to write:
> var x = "\u006eew";
> it'd be obvious that you're referring to the codepoint in the source
> (written in ASCII or something ASCII-compatible) so that it doesn't
> get garbled in the editors of your fellow programmers who might not be
> using the same locale.
> It's strange that you would do that in an identifier because in no
> one's editor would the editor replace it with the unicode character it
> refers to.
> I've always thought JS identifiers were a little too liberal with what
> is allowed, and in that spirit I think it should continue - but Grumpy
> Cat[1] disapproves.
> 1:
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