April 10 2014 Meeting Notes
brendan at mozilla.org
Thu Apr 24 13:29:51 PDT 2014
Sorry for the confusion -- my "such a change" was about changing
@@iterator itself, e.g. not defining it on a generator, or trying
somehow to guarantee freshness.
I agree, return automation makes sense for any delimited form that
implicitly calls @@iterator.
There still may be an open issue, though: Python has ref-counting and
pre-mortem finalization via close, last I checked. JS won't have any
such thing. So are there ,in ES6, undelimited forms that implicitly call
@@iterator and that won't implicitly maybe-call return?
Jason Orendorff wrote:
> On Thu, Apr 24, 2014 at 2:16 PM, Brendan Eich<brendan at mozilla.org> wrote:
>> > The only proposal (let's table whether the name is 'return' or @@return) is
>> > whether for-of constructs should have a finally maybe-call of the iterator's
>> > return method, if present. Like SpiderMonkey's JS1.7-1.8 close method, based
>> > in part on Python 2.5 and up.
> But in Python, closing iterators is part of the protocol. It isn't
> mentioned in the language specification (Python does not have a
> detailed spec) but all language and library facilities that consume
> iterables do it, not just for loops.
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