Why not NodeList#forEach :\?

David Bruant bruant.d at gmail.com
Mon Jun 11 06:18:26 PDT 2012

Le 11/06/2012 15:13, Hemanth H.M a écrit :
> Uber kool! Thanks a ton David!
> |npm install es6-shim # wow :) Shall blog about this!
> |
> Well, Map() and Set() is already there is FF13, it's 
> an experimental API right? Experimental means it can be chucked off or 
> it shall be modified drastically ?  ( More Java like APIs :\ )
> Well {} behaved liked map and well for sets we can use 
> [].sort.filter(function(v,i,o){return v!==o[i-1];}
The major use case for Maps and Sets (as far as i'm concerned) is the 
ability to use objects as keys. Having built-in implementation of these 
potentially enable O(1)-ish lookups (which is impossible to implement in 
As to Maps and {} being equivalent, that's true expect when it's not, 
like when you want to use pseudo properties like __proto__ or 
__noSuchMethod__ as keys. Some folks tried to use objects as maps and 
got burned [1]. See Caja's StringMap [2] for a workaround when you only 
need strings as keys.


[1] http://productforums.google.com/forum/#!topic/docs/0hQWeOvCcHU
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.mozilla.org/pipermail/es-discuss/attachments/20120611/6bb1231b/attachment.html>

More information about the es-discuss mailing list