All uses of @@species are to be removed from Promise.race and Promise.all. The 
committee achieved consensus on this, without you.


________________________________
From: es-discuss <es-discuss-boun...@mozilla.org> on behalf of C. Scott Ananian 
<ecmascr...@cscott.net>
Sent: Wednesday, November 18, 2015 18:15
To: Boris Zbarsky
Cc: es-discuss@mozilla.org list
Subject: Re: resolve()/reject() on Promise subclasses and @@species


Unfortunately, it's not just a specification device, it has a real effect on 
the behavior of Promise subclasses.  In the case of TimeoutPromise, for 
instance, it affects whether the timeouts apply to *each promise in the array* 
or just to the final result Promise.

I'm hearing through the grapevine (https://github.com/tc39/ecma262/issues/151) 
that it has been decided to change the behavior of Promise.all/race. Have you 
decided to adopt the spec language I proposed above?  There has been precious 
little actual discussion of it, certainly not enough for me to claim any sort 
of consensus has been reached (except perhaps by default, since no one has  
advocated for alternatives).

[https://avatars3.githubusercontent.com/u/3309637?v=3&s=400]<https://github.com/tc39/ecma262/issues/151>

Remove @@species lookup from Promise.all() and Promise ...
Remove @@species lookup from Promise.all() and Promise.race() #151
Read more...<https://github.com/tc39/ecma262/issues/151>



  --scott

On 11/4/15 11:22 PM, C. Scott Ananian wrote:
see my previous message for the exact wording proposal which
changes step 6.

https://esdiscuss.org/topic/performpromiseall#content-6 you mean?

I don't have a strong opinion on it, honestly.  The existence of the 
intermediate promises in all/race seems mostly to be a specification device to 
make it easier to deal with people passing in not-thenable-at-all values, from 
my point of view, so I'm not sure I have a principled opinion on how they 
should be constructed.

-Boris
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