Actually, I take that back, FF Nightly is behaving differently this morning than it was earlier in the week. Go figure
> On Nov 7, 2015, at 12:06 PM, Caitlin Potter <[email protected]> wrote: > > It should be reserved, logically — but the spec does not explicitly forbid > this. Unless you take Allen’s “it’s a bold sequence of characters, > therefore…” argument, which is all well and good, but is only really > explained in the spec in http://tc39.github.io/ecma262/#sec-grammar-notation > <http://tc39.github.io/ecma262/#sec-grammar-notation> in the first paragraph > — and then further, unicode escapes tend to be eagerly converted, so “appear > in a script exactly as written” can be misleading. Explicit static semantics > work a lot better for this sort of thing, as they can be easily referenced. > > So, in that case, it’s SpiderMonkey with the bug in the case of accessor > methods, and Chrome without it, while Firefox behaves correctly with escaped > `new . target`, and Chrome doesn’t. > >> On Nov 7, 2015, at 11:57 AM, Eric Suen <[email protected] >> <mailto:[email protected]>> wrote: >> >> So escaped ReservedWords are not valid as ReservedWords nor >> Identifier, what is it then? >> >> And in export { IdentifierName }, why it's IdentifierName not >> Identifier. since IdentifierName only valid as Property in >> ObjectLiteral or Method in Class, is there any way to define >> ReservedWords as local name? >> >> 'get'/'set' is ContextuallyReservedIdentifier, maybe that's the reason? >> >> >> On Sat, Nov 7, 2015 at 11:32 PM, Caitlin Potter <[email protected] >> <mailto:[email protected]>> wrote: >>> That it works in Chrome is a bug, which will hopefully be fixed by Monday >>> or Tuesday! >>> >>> Per http://tc39.github.io/ecma262/#sec-keywords >>> <http://tc39.github.io/ecma262/#sec-keywords>, “new” is a Keyword, which >>> makes it a ReservedWord. >>> >>> Per >>> http://tc39.github.io/ecma262/#sec-identifiers-static-semantics-early-errors >>> >>> <http://tc39.github.io/ecma262/#sec-identifiers-static-semantics-early-errors>, >>> under the >>> “Identifier: IdentifierName but not ReservedWord” section, the second early >>> error applies here. This applies to >>> `new`, which is always a reserved word. So whenever an Identifier is >>> expected, if it contains UnicodeEscapeSequences which result in the same >>> StringValue as a ReservedWord, it’s an error. >>> >>> The spec is similarly explicit in saying that escaped ReservedWords are not >>> valid as ReservedWords. Browsers behave differently here (for instance, >>> http://jsfiddle.net/jd51pqae/ <http://jsfiddle.net/jd51pqae/> <<< at the >>> time of this writing Webkit Nightly prints the text, while other browsers >>> SyntaxError. in Chromes case, this is because it’s tokenized as an >>> Identifier, so the second Identifier “f” is unexpected when parsing a >>> MemberExpression. SpiderMonkey is doing a nice job of reporting clean >>> errors for this kind of thing, that are easier to understand. >>> >>> There are some odd points though: >>> >>> 1. ReservedWord restrictions never apply to `get` or `set`, even in >>> ObjectLiterals (though currently Chrome fails to treat `g\u{65}t` or >>> `s\u{65}t` as an accessor prefix, this is a bug). >>> >>> 2. In the case of “new.target”, it’s technically legal to write >>> `new.t\u{61}rget`, but this mostly just seems like an oversight in the spec. >>> >>>> On Nov 7, 2015, at 9:50 AM, Eric Suen <[email protected] >>>> <mailto:[email protected]>> wrote: >>>> >>>> "The ReservedWord definitions are specified as literal sequences of >>>> specific SourceCharacter elements. A code point in a ReservedWord >>>> cannot be expressed by a \ UnicodeEscapeSequence." - what does it >>>> mean? >>>> >>>> The following code is valid in Chrome, but invalid in firefox and IE. >>>> >>>> var \u006eew = 1; // \u006e = 'n' >>>> >>>> and valid in Babel/Traceur, invalid in typescript/esprima... >>>> >>>> -- >>>> ------------------------------------------------ >>>> Spket IDE - Development Tool for RIA. >>>> >>>> http://www.spket.com <http://www.spket.com/> >>>> _______________________________________________ >>>> es-discuss mailing list >>>> [email protected] >>>> https://mail.mozilla.org/listinfo/es-discuss >>> >> >> >> >> -- >> ------------------------------------------------ >> Spket IDE - Development Tool for RIA. >> >> http://www.spket.com <http://www.spket.com/> >
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