[Python-Dev] Tricky way of of creating a generator via a comprehension expression

[Ivan Levkivskyi]

On 23 November 2017 at 12:38, Ivan Levkivskyi <levkivskyi at gmail.com> wrote:

> On 23 November 2017 at 11:55, Nick Coghlan <ncoghlan at gmail.com> wrote:
>
>> On 23 November 2017 at 18:11, Greg Ewing <greg.ewing at canterbury.ac.nz>
>> wrote:
>>
>>> Ivan Levkivskyi wrote:
>>>
>>>> "People sometimes want to refactor for-loops containing `yield` into a
>>>> comprehension but that doesn't work (particularly because of the hidden
>>>> function scope) - lets make it a SyntaxError"
>>>>
>>>
>>> Personally I'd be fine with removing the implicit function
>>> scope from comprehensions and allowing yield in them, since
>>> the semantics of that are clear.
>>>
>>
>> People keep saying this, but seriously, those semantics aren't clear at
>> all once you actually start trying to implement it.
>>
>>
> If Serhiy will implement his idea (emitting for-loop bytecode inside a
> try-finally), then I see no problems accepting it as a fix.
>

Also I think it makes sense to keep discussion in one place, i.e. either
here xor at https://bugs.python.org/issue10544

--
Ivan
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