Array comprehension syntax

Brendan Eich brendan at
Sat Sep 22 09:21:52 PDT 2012

Perhaps the thing to do is keep to Python: for+ if? if you get my 

Separate issues:

* Paren-free heads can run into trouble: But 
in a comprehension, the subsequent 'for', 'if', or ']' (or ')' for a 
genexp) helps, so this may not be a problem in fact. We need to work 
through it, though.

* We don't need to worry about ECMA-357 (E4X) for-each-in too much here. 
SpiderMonkey can cope, the standard shouldn't contextually reserve 
'each' or anything.


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