Null iterable in for-of?

Allen Wirfs-Brock allen at
Fri Jun 13 09:50:05 PDT 2014

On Jun 12, 2014, at 5:01 PM, Jeff Walden wrote:

> On 06/12/2014 03:25 PM, Brendan Eich wrote:
>> Actually, if memory serves, IE JScript tolerated null and undefined on right of for-in. SpiderMonkey and my ur-JS implementation, Mocha, did not. Someone with the jwz nostalgia Netscape 2/3 browsers, please test.
> Hmm.  I'm reciting tribal knowledge that I'm probably misremembering at this point, so I bet you're right.

It isn't listed as a JScript deviation in 
But says that IE introduced it.

I was probably wrong in pinning this on Crock, as it doesn't show up in his "ES4" wish list. 

Also see if you have any interest in tracing the history of this change.

>> I don't think bug-hiding precedent trumps bug-finding, personally. Allen?
> Agreed.

It sounds like the the tide is swinging towards bug finding rather than consistency in this case.  I'm fine with and and will update the spec. accordingly.


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