[Python-ideas] Introduce collections.Reiterable

[Nick Coghlan]

On 19 Sep 2013 19:14, "Neil Girdhar" <mistersheik at gmail.com> wrote:
>
> I am proposing a new class "Reiterable" that is a subclass of Iterable.
 For example, a dictionary view is a reiterable.  It would be fine to pass
such an object to the function f.

I'm afraid simply repeating your proposal still doesn't answer my question.
You have indicated that you are trying to identify things that are
iterable, but not iterators. That is already possible using a second
isinstance check to exclude iterators.

So, what is the value you see in adding a new ABC to further simplify an
already simple check?

Cheers,
Nick.

>
> Best,
> Neil
>
>
> On Thu, Sep 19, 2013 at 5:12 AM, Nick Coghlan <ncoghlan at gmail.com> wrote:
>>
>>
>> On 19 Sep 2013 18:59, "Neil Girdhar" <mistersheik at gmail.com> wrote:
>> >
>> > Well, generators are iterable, but if you write a function like:
>> >
>> > def f(s):
>> >      for x in s:
>> >              do_something(x)
>> >      for x in s:
>> >              do_something_else(x)
>> >
>> > x should not be a generator.  I am proposing adding a function to
itertools like auto_reiterable that would take s and give you an reiterable
in the most efficient way possible.
>>
>> Generators *are* iterators, though, so they fail the second half of the
check. Hence my question - is there any obvious case where "iterable but
not an iterator" gives the wrong answer?
>>
>> Cheers,
>> Nick.
>>
>> >
>> >
>> > On Thu, Sep 19, 2013 at 4:32 AM, Nick Coghlan <ncoghlan at gmail.com>
wrote:
>> >>
>> >> My question would be, does the new class add anything that isn't
>> >
>> >
>> >
>
>
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