[Python-Dev] semantics of subclassing things from itertools

[Serhiy Storchaka]

On 10.09.15 15:50, Maciej Fijalkowski wrote:
> On Thu, Sep 10, 2015 at 10:26 AM, Serhiy Storchaka <storchaka at gmail.com> wrote:
>> There is another reason why itertools iterators can't be implemented as
>> simple generator functions. All iterators are pickleable in 3.x.
>
> maybe the documentation should reflect that? (note that generators are
> pickleable on pypy anyway)

This pickling is not compatible with CPython. So even if itertools 
classes would not subclassable, you would need to implement itertools 
iterators as classes.