The impact seems minimal (how often would this occur in the wild). I don't like adding restrictions to the language for the sake of protecting a possible defect, but I don't really see this as a problem since it's not exactly a best practice to use reserved keywords as property names anyways ;) (re: CSFLD)
- peter > It does seem reasonable to disallow new lines in that context. > > --Oliver > > On Aug 24, 2010, at 1:53 PM, Allen Wirfs-Brock wrote: > >> Consider the following JavaScript code fragment: >> >> var x=foo. >> if (a>b) -bar; >> >> If this showed up in real code, it would probably be either as a >> typo where either the actual property name for foo was left off >> or because of a mental lapse by an old Smalltalk programmer who >> was used to using . instead of ; to terminate statements. >> Regardless, it will validly parse identically to the following >> single line formulation: >> >> var x=foo.if(a>b)-bar; >> >> The ES5 grammar for a dotted property access is: >> >> CallExpression :: >> CallExpression . IdentifierName >> >> Where IdentifierName includes all possible identifiers including >> reserved words. The above confusion could have been avoided if >> we had instead defined things as: >> >> CallExpression :: >> CallExpression . Identifier >> CallExpression . [no LineTerminator here] ReservedWord >> >> Is this the grammar we should have used for ES5? It's too late >> to make this change in the ES5 spec. but if we had consensus >> that this is how it should be specified in Harmony we might also >> get the emerging ES5 implementations to also follow this >> interpretations. >> >> Thoughts? It's kind of hooky to have semi-arbitrary restrictions >> on line terminator placement. But we already have them in order >> to make semi-colon insertion more sane and arguably such >> restrictions reasonably go hand-in-hand with allowing context >> sensitive use of reserved words. >> >> Allen >> _______________________________________________ >> es-discuss mailing list >> [email protected] >> https://mail.mozilla.org/listinfo/es-discuss >> > _______________________________________________ > es-discuss mailing list > [email protected] > https://mail.mozilla.org/listinfo/es-discuss _______________________________________________ es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
