Nannying (was: Array comprehension syntax)

Brendan Eich brendan at mozilla.com
Tue Sep 25 13:30:13 PDT 2012


Allen Wirfs-Brock wrote:
> I think we should go the all AssignmentExpression route.  It avoid ArrayLiteral-like comma confusion in all three positions.  It is also a simpler set of rules to teach and remember. 
>

It's different from the statement forms, though.

Again, this is a non-issue in practice. Nobody writes comma expressions 
in those places.

>    Finally, it leave open the future possibility of ArrayLiterals that have comprehensions in element positions. (not that I'm recommending this...) 
>

Why wouldn't comprehensions be allowed in ArrayLiteral element 
positions? That falls out of any grammar that puts comprehensions at 
PrimaryExpression precedence, where they must be.

This is not a huge deal and I defer to Jason as champion-apparent, but 
it does seem worth agreeing on the same Expression non-terminal for if 
and for conditions in both statements and comprehensions, or finding a 
better reason to change in the latter.

/be


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