[Python-Dev] PEP 484 (Type Hints) -- the next draft is here

[Guido van Rossum]

Maybe the thing to fix then is the inspect module, not asyncio? Anyway, let
is know via tickets.

On Sat, Apr 18, 2015 at 12:29 PM, Stefan Behnel <stefan_ml at behnel.de> wrote:

> Stefan Behnel schrieb am 18.04.2015 um 19:39:
> > Guido van Rossum schrieb am 18.04.2015 um 18:38:
> >> That's a good question. We *could* make it so that you can subclass
> >> Generator and instantiate the instances; or we could even make it do
> some
> >> structural type checking. (Please file a pull request or issue for this
> at
> >> github.com/ambv/typehinting .)
> >>
> >> But perhaps we should also change asyncio?
> >> What check are you talking about?
> >
> >
> https://hg.python.org/cpython/file/439517000aa2/Lib/asyncio/coroutines.py#l169
> >
> > The current (3.5alpha) check in iscoroutine() is an instance check
> against
> > _COROUTINE_TYPES, which contains types.GeneratorType and another wrapper
> > type. It excludes objects that implement the coroutine protocol without
> > being Python generators, e.g. Cython compiled generators, which mimic the
> > Python generator interface without having byte code in them (meaning,
> they
> > are not C-level compatible with Python generators). I'm sure the same
> > applies to other compilers like Numba or Nuitka. Supporting asyncio in
> > recent Python releases thus means monkey patching _COROUTINE_TYPES and
> > adding another type to it. Given that it's not a public interface, this
> > seems a bit fragile.
> >
> > It also seems that this code only appeared somewhere in the 3.4.x release
> > series. Older versions were even worse and did a straight call to
> > inspect.isgenerator() in their iscoroutine() function, which means that
> the
> > whole function needed to be replaced and wrapped (and even that didn't
> fix
> > all places where inspect was used).
>
> Hmm, looks like I remembered it incorrectly. Monkey patching the inspect
> module is required in both versions as it's being used in more places,
> especially the coroutine wrappers. I'll see how I can get it working with
> Cython and then open tickets for it.
>
> Stefan
>
>
> _______________________________________________
> Python-Dev mailing list
> Python-Dev at python.org
> https://mail.python.org/mailman/listinfo/python-dev
> Unsubscribe:
> https://mail.python.org/mailman/options/python-dev/guido%40python.org
>



-- 
--Guido van Rossum (python.org/~guido)
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-dev/attachments/20150418/316f7a10/attachment.html>