[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Changes by Yury Selivanov yseliva...@gmail.com: -- dependencies: +Awaitable ABC incompatible with functools.singledispatch ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Stefan Behnel added the comment: See issue 24400 regarding a split of yield-based generators and async-def coroutines at a type level. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Yury Selivanov added the comment: Guido, Stefen, please see issue24383. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Yury Selivanov added the comment: Hmm, but IMHO a) the new syntax isn't just for asyncio and b) awaiting a Future seems like a *very* reasonable thing to do. I think opening a new ticket for this is a good idea. Stefan, I honestly have bo idea what concurrent.Future.__await__ would do. There is no loop for concurrent module. If you have a patch with tests in mind, please open a separate issue (targeting 3.6). -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Alex Grönholm added the comment: Was __await__() deliberately left out of concurrent.futures.Future or was that an oversight? Or am I misunderstanding something? -- nosy: +alex.gronholm ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Yury Selivanov added the comment: Was __await__() deliberately left out of concurrent.futures.Future or was that an oversight? Or am I misunderstanding something? I don't think concurrent.Future is supposed to be used with asyncio (in 'yield from' or 'await' expressions). -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Roundup Robot added the comment: New changeset 1e9e0664ee9b by Yury Selivanov in branch '3.5': Issue 24017: Make PyEval_(Set|Get)CoroutineWrapper private https://hg.python.org/cpython/rev/1e9e0664ee9b New changeset 6fcb64097b1c by Yury Selivanov in branch 'default': Issue 24017: Make PyEval_(Set|Get)CoroutineWrapper private https://hg.python.org/cpython/rev/6fcb64097b1c -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Roundup Robot added the comment: New changeset a0a699b828e7 by Yury Selivanov in branch '3.5': Issue 24017: Add a test for CoroWrapper and 'async def' coroutines https://hg.python.org/cpython/rev/a0a699b828e7 New changeset 89521ac669f0 by Yury Selivanov in branch 'default': Issue 24017: Add a test for CoroWrapper and 'async def' coroutines https://hg.python.org/cpython/rev/89521ac669f0 -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Roundup Robot added the comment: New changeset 0708aabefb55 by Yury Selivanov in branch '3.4': Issue 24017: Fix asyncio.CoroWrapper to support 'async def' coroutines https://hg.python.org/cpython/rev/0708aabefb55 New changeset 1dc232783012 by Yury Selivanov in branch '3.5': Issue 24017: Fix asyncio.CoroWrapper to support 'async def' coroutines https://hg.python.org/cpython/rev/1dc232783012 New changeset 2e7c45560c38 by Yury Selivanov in branch 'default': Issue 24017: Fix asyncio.CoroWrapper to support 'async def' coroutines https://hg.python.org/cpython/rev/2e7c45560c38 -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Yury Selivanov added the comment: Stefan, Because of https://mail.python.org/pipermail/python-committers/2015-May/003410.html I've decided to commit 24315 and 24316 today. Please try to check that everything works before new beta 2. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Yury Selivanov added the comment: Tried it, works for me. Thanks! This is really good news! Thanks! -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Stefan Behnel added the comment: Tried it, works for me. Thanks! -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Stefan Behnel added the comment: Yield-from iterates, and a coroutine is not supposed to be iterable, only awaitable (at least, that's what all error messages tell me when I try it). So why should yield from work on them? What if foo() was not an Iterable but a Coroutine? Should yield from then call __await__ on it internally? I would find that *really* surprising, but given the above, I think it would be necessary to achieve consistency. This is a special backwards-compatibility thing. That only answers the half-serious first part of my question. ;) This code only works if foo() returns an Iterable, including a (yield) coroutine: @types.coroutine def bar(): return (yield from foo()) It does not work for arbitrary Coroutines as they are not iterable, but it might trick people into writing code that fails for non-coroutine Coroutines. I'd rather like to have this either work for any Coroutine or not at all. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Stefan Behnel added the comment: BTW, given that iter(iterator) works and returns the iterator, should we also allow await x.__await__() to work? I guess that would be tricky to achieve given that __await__() is only required to return any kind of arbitrary Iterator, and Iterators cannot be awaited due to deliberate restrictions. But it might be nice to have for wrapping purposes. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Stefan Behnel added the comment: Can't your Coroutine object return itself from its __await__, and implement __next__? Like genobject in CPython simply returns self from its __iter__. That was my first try, sure, and it mostly worked. It has a drawback, though: it's an incomplete implementation of the Iterator protocol. It's still (mostly) an Iterator, but not an Iterable, so it depends on how you use it whether you notice or not, and whether it works at all with other code or not. There's a test for a failing next(coro) in your test suite, for example, which would then not fail in Cython. OTOH, code cannot assume that calling iter() or for-looping over on an Iterable is a sane thing to do, because it doesn't work for Python's generator type based coroutine either, so we might get away with it... All of these little details make this trick appear like a potential source of subtle inconsistencies or incompatibilities. But given that there will almost certainly remain inconsistencies for compiled Python code, I'm not sure yet which approach is better. It's not impossible that I'll end up going back to the original design. I guess I'll eventually have to include some benchmarks in the decision. On a related note, my testing made me stumble over this code in asyncio.tasks.Task(): if coro.__class__ is types.GeneratorType: self._coro = coro else: self._coro = iter(coro) # Use the iterator just in case. This seems wrong regardless of how you look at it. And it definitely fails with both designs. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Roundup Robot added the comment: New changeset dfa0288c91fd by Yury Selivanov in branch '3.5': Issue 24017: Drop getawaitablefunc and friends in favor of unaryfunc. https://hg.python.org/cpython/rev/dfa0288c91fd New changeset 99dcca3466d3 by Yury Selivanov in branch 'default': Issue 24017: Drop getawaitablefunc and friends in favor of unaryfunc. https://hg.python.org/cpython/rev/99dcca3466d3 -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Roundup Robot added the comment: New changeset 09327f653ec5 by Yury Selivanov in branch '3.4': asyncio: Drop some useless code from tasks.py. https://hg.python.org/cpython/rev/09327f653ec5 New changeset adf72cffceb7 by Yury Selivanov in branch '3.5': asyncio: Drop some useless code from tasks.py. https://hg.python.org/cpython/rev/adf72cffceb7 New changeset 9c0a00247021 by Yury Selivanov in branch 'default': asyncio: Drop some useless code from tasks.py. https://hg.python.org/cpython/rev/9c0a00247021 -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Changes by Yury Selivanov yseliva...@gmail.com: -- dependencies: +collections.abc: Coroutine should be derived from Awaitable ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Yury Selivanov added the comment: Stefan, I've already committed fixes for: 1. getawaitablefunc / aiternextfunc / getaiterfunc - unaryfunc 2. strange code in tasks.py doing coro = iter(coro) is now removed I've also opened a couple of new issues (with patches for a review): 1. abc.Coroutine derived from abc.Awaitable: issue 24315 2. types.coroutine() to support Cython objects: issue 24316 I'll reply to some of your messages below: Another question: is it ok if Cython implements and uses the tp_as_async slot in all Py3.x versions (3.2+)? It shouldn't hurt, [..] I think it's totally OK, given that you can workaround the drawback you mentioned. Can't your Coroutine object return itself from its __await__, and implement __next__? Like genobject in CPython simply returns self from its __iter__. That was my first try, sure, and it mostly worked. It has a drawback, though: it's an incomplete implementation of the Iterator protocol. It's still (mostly) an Iterator, but not an Iterable, so it depends on how you use it whether you notice or not, and whether it works at all with other code or not. There's a test for a failing next(coro) in your test suite, for example, which would then not fail in Cython. [..] I think if next(cython_coro) does not fail is acceptable. It's not ideal, but the purpose of Cython is to make Python code as fast as possible, so I'd try to avoid having any kind of thin wrappers around Cyhton coroutines. -- dependencies: +Fix types.coroutine to accept objects from Cython ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Stefan Behnel added the comment: Thanks Yury, I'll give it a try ASAP. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Roundup Robot added the comment: New changeset 843fe7e831a8 by Yury Selivanov in branch '3.5': Issue 24297: Update symbol.py. See also issue 24017. https://hg.python.org/cpython/rev/843fe7e831a8 New changeset 87509d71653b by Yury Selivanov in branch 'default': Issue 24297: Update symbol.py. See also issue 24017. https://hg.python.org/cpython/rev/87509d71653b -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Stefan Behnel added the comment: It *is* correct, see PEP 492. Awaitable is either a coroutine *or* an object with an __await__ method. coroutine, yes. But Coroutine? Shouldn't the Coroutine ABC then require __await__ to be implemented? Maybe even by inheriting from Awaitable? Just implement tp_await/__await__ for coroutine-like objects coming from C-API or Cython. Sure, that's how it's done. (Specifically, Coroutine is not an Iterable/Iterator, but its __await__() returns a thin Iterator that simply calls into the Generator code. A bit annoying and slowish, but that's what it takes.) I was just wondering how Cython should compile Python code that makes use of this decorator. The Coroutine and Generator types are separated in Cython now, and I think that's actually the right thing to do. This types.coroutine() decorator and special casing in CPython's code base gets a bit in the way here. In general, iteration protocol is still the foundation for Future-like objects That's not really reflected in the ABCs, is it? -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Nick Coghlan added the comment: Thanks for highlighting these Stefan - you guessed correctly that I'd missed them on the review. For your first question, I agree getawaitablefunc / aiternextfunc / getaiterfunc should all be dropped and replaced with the existing unaryfunc. For your second question, I agree it makes more sense for Coroutine to inherit from Awaitable than it does to have it registered with it. For the other three, I don't have a strong opinion, except that we should make sure that whatever we do on the CPython side works by default for Cython. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Nick Coghlan added the comment: Given that tp_call is just ternaryfunc, my guess would be because when the iterator protocol was added, someone went with function-pointer-type-per-slot rather than function-pointer-type-per-call-signature. We *are* a little inconsistent here (e.g. reprfunc could also just use the unaryfunc signature), but Stefan's right that that isn't a good reason to *add* to the inconsistency. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Yury Selivanov added the comment: It *is* correct, see PEP 492. Awaitable is either a coroutine *or* an object with an __await__ method. coroutine, yes. But Coroutine? Shouldn't the Coroutine ABC then require __await__ to be implemented? Maybe even by inheriting from Awaitable? This is an interesting idea. Practically, when you register something as a Coroutine, you expect it to be compatible with ‘await’ expressions. And that’s only possible if __await__ is implemented. I’m curious what Guido and Nick think about this. I think that we can derive Coroutine from Awaitable. Just implement tp_await/__await__ for coroutine-like objects coming from C-API or Cython. Sure, that's how it's done. (Specifically, Coroutine is not an Iterable/Iterator, but its __await__() returns a thin Iterator that simply calls into the Generator code. A bit annoying and slowish, but that's what it takes.) Can't your Coroutine object return itself from its __await__, and implement __next__? Like genobject in CPython simply returns self from its __iter__. I was just wondering how Cython should compile Python code that makes use of this decorator. The Coroutine and Generator types are separated in Cython now, and I think that's actually the right thing to do. This types.coroutine() decorator and special casing in CPython's code base gets a bit in the way here. I think we can update types.coroutine to continue using CO_ITERABLE_COROUTINE for pure python generator functions. And for something foreign we can use your proposed design. Would that be OK? In general, iteration protocol is still the foundation for Future-like objects That's not really reflected in the ABCs, is it? Awaitable has its __await__ defined as a generator... -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Yury Selivanov added the comment: For your first question, I agree getawaitablefunc / aiternextfunc / getaiterfunc should all be dropped and replaced with the existing unaryfunc. I have no problem with that. But why do we have iternextfunc getiterfunc (no a prefix)? -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Stefan Behnel added the comment: I added a couple of review comments to patch 6, but since no-one has responded so far, I guess they simply haven't been noticed. So I'll just repeat them here. 1) getawaitablefunc / aiternextfunc / getaiterfunc Is there a reason why these need to have their specific C type name instead of just reusing unaryfunc, or at least the existing iternextfunc / getiterfunc? They are unprefixed global names in the C namespace and I think we should be careful when adding more of those. 2) Awaitable.register(Coroutine) I think this is incorrect. A Coroutine is not Awaitable unless it also implements __await__. How else should it be awaited? 3) I propose to use this wrapping code as a fallback for types.coroutine() in the case that a Generator (ABC) is passed instead of a generator (yield): class types_coroutine(object): def __init__(self, gen): self._gen = gen class as_coroutine(object): def __init__(self, gen): self._gen = gen self.send = gen.send self.throw = gen.throw self.close = gen.close def __await__(self): return self._gen def __call__(self, *args, **kwargs): return self.as_coroutine(self._gen(*args, **kwargs)) Note that the resulting Awaitable Coroutine type is not an Iterable. This differs from a (yield) coroutine, but it matches the Coroutine and Awaitable protocols, and the intention to separate both in order to avoid mistakes on user side. Additionally, regarding the tests: 4) def test_func_2(self): async def foo(): raise StopIteration with self.assertRaisesRegex( RuntimeError, generator raised StopIteration): run_async(foo()) Why is this actually necessary? I'm aware that it's also mentioned in the PEP, but is there an actual reason why a coroutine should behave the same as a generator here? Is it just an implementation detail for legacy reasons because generators and coroutines happen to share the same type implementation? (I don't think they need to, BTW.) 5) def test_func_8(self): @types.coroutine def bar(): return (yield from foo()) async def foo(): return 'spam' self.assertEqual(run_async(bar()), ([], 'spam') ) I find it surprising that this works at all. Yield-from iterates, and a coroutine is not supposed to be iterable, only awaitable (at least, that's what all error messages tell me when I try it). So why should yield from work on them? What if foo() was not an Iterable but a Coroutine? Should yield from then call __await__ on it internally? I would find that *really* surprising, but given the above, I think it would be necessary to achieve consistency. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Yury Selivanov added the comment: 2) Awaitable.register(Coroutine) I think this is incorrect. A Coroutine is not Awaitable unless it also implements __await__. How else should it be awaited? It *is* correct, see PEP 492. Awaitable is either a coroutine *or* an object with an __await__ method. Generally, being an awaitable means that the object can be used in await expression. 3) I propose to use this wrapping code as a fallback for types.coroutine() in the case that a Generator (ABC) is passed instead of a generator (yield): Just implement tp_await/__await__ for coroutine-like objects coming from C-API or Cython. In general, iteration protocol is still the foundation for Future-like objects, so there is nothing wrong with this. Generator ABC isn't supposed to be used with await expression. 4) def test_func_2(self): async def foo(): raise StopIteration with self.assertRaisesRegex( RuntimeError, generator raised StopIteration): run_async(foo()) Why is this actually necessary? I'm aware that it's also mentioned in the PEP, but is there an actual reason why a coroutine should behave the same as a generator here? Is it just an implementation detail for legacy reasons because generators and coroutines happen to share the same type implementation? (I don't think they need to, BTW.) Coroutines are implemented on top of generators. Until we clearly separate them (in 3.6?) I don't think we should allow coroutines to bubble up StopIteration. 5) def test_func_8(self): @types.coroutine def bar(): return (yield from foo()) async def foo(): return 'spam' self.assertEqual(run_async(bar()), ([], 'spam') ) I find it surprising that this works at all. Yield-from iterates, and a coroutine is not supposed to be iterable, only awaitable (at least, that's what all error messages tell me when I try it). So why should yield from work on them? What if foo() was not an Iterable but a Coroutine? Should yield from then call __await__ on it internally? I would find that *really* surprising, but given the above, I think it would be necessary to achieve consistency. This is a special backwards-compatibility thing. In general, generators cannot yield-from coroutines (unless they are decorated with @types.coroutine). -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Stefan Behnel added the comment: Another question: is it ok if Cython implements and uses the tp_as_async slot in all Py3.x versions (3.2+)? It shouldn't hurt, but it would speed up async/await in Cython at least under Py3.x. Only Py2.6/7 would then have to resort to calling __await__() etc. at the Python level. One drawback is that Py3.5 currently (needlessly) checks that tp_reserved and tp_richcompare are both implemented, but that can be worked around by also implementing the latter... -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Roundup Robot added the comment: New changeset ff983ee10b3e by Yury Selivanov in branch 'default': Issue 24017: Use abc.Coroutine in inspect.iscoroutine() function https://hg.python.org/cpython/rev/ff983ee10b3e -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Yury Selivanov added the comment: Closing the issue. I'll open a new one for missing documentation. Thanks! -- components: +Interpreter Core resolution: - fixed stage: patch review - resolved status: open - closed ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Changes by Yury Selivanov yseliva...@gmail.com: -- dependencies: +PEP 492: Documentation ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Roundup Robot added the comment: New changeset 0d80d46adfdb by Yury Selivanov in branch 'default': Issue 24017: More tests for 'async for' and 'async with'. https://hg.python.org/cpython/rev/0d80d46adfdb -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Guido van Rossum added the comment: BTW, a shout out to Nick for doing most of the review for this monster patch. Thanks! -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Changes by Yury Selivanov yseliva...@gmail.com: -- dependencies: +PEP 492: Add AsyncIterator and AsyncIterable to collections.abc ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Nick Coghlan added the comment: A bit more detail on the patch-as-merged: it has all of Yury's new tests, but the actual bug turned out to just be a missing INCREF/DECREF pair in WITH_CLEANUP_START and WITH_CLEANUP_FINISH. In the success case the reference counting errors cancelled each other out without causing a problem, as there was always a second live reference to the exception object on the stack. However, in the case where the awaitable threw an exception the standard exception handling machinery took care of removing the saved exception from the stack, and correctly decremented the reference count, which then caused problems due to the missing INCREF in WITH_CLEANUP_START. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Roundup Robot added the comment: New changeset 9d2c4d887c19 by Yury Selivanov in branch 'default': Issue #24017: Unset asyncio event loop after test. https://hg.python.org/cpython/rev/9d2c4d887c19 -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Roundup Robot added the comment: New changeset e39fd5a8501a by Nick Coghlan in branch 'default': Issue 24017: fix for async with refcounting https://hg.python.org/cpython/rev/e39fd5a8501a -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Yury Selivanov added the comment: Is there are a specific reason this implicit exception handler can't be decomposed and implemented using the same opcodes as are used to implement explicit exception handlers? I don't think it's possible to replace ASYNC_WITH_CLEANUP_EXCEPT opcode with some combination of existing opcodes. What might be possible is to implement 'async with' without using WITH_CLEANUP_* opcodes at all. Let me try that. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Nick Coghlan added the comment: I'm going to dig into this one locally, as it sounds to me like something may be going wrong with the refcounts in the complex stack manipulation involved in WITH_CLEANUP. It seems plausible that there's a genuinely missing incref/decref pair somewhere in the non-exceptional path, which the proposed new opcode is working around. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Yury Selivanov added the comment: I'd suggest you to look at ceval.c before PEP 492 patch then (where there is just one WITH_CLEANUP opcode). -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Nick Coghlan added the comment: Avoiding WITH_CLEANUP entirely in the async case also sounds like a plausible approach. Either way, I'm also on IRC now if you want to thrash this out there. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Yury Selivanov added the comment: Nick, Guido, Attached is a patch that fixes a refleak in 'async with' implementation. The problem is related to WITH_CLEANUP_START/WITH_CLEANUP_FINISH opcodes. For regular 'with' statements, these opcodes go one after another (essentially, it was one opcode before 'async with'). For 'async with' statements, we have a GET_AWAITABLE/YIELD_FROM pair between them. Now, if an error occurred during running a GET_AWAITABLE or a YIELD_FROM opcode, WITH_CLEANUP_FINISH was unreachable. All blocks were correctly unwound by the eval loop, but exception object got too many DECREFS. My solution is to continue using WITH_CLEANUP_START/WITH_CLEANUP_FINISH opcodes, but use SETUP_EXCEPT to guard them and nested YIELD_FROM and GET_AWAITABLE. In case of an exception, I propose to use another new opcode -- ASYNC_WITH_CLEANUP_EXCEPT. It unwinds the block set up by SETUP_EXCEPT, restores exception, NULLifies a copy of exception in the stack and does 'goto error', letting eval loop do the rest. ./python.exe -m test -R3:3 test_coroutines with this patch reports no refleaks. I also updates test_coroutines with a lot of new 'async with' tests, I think that I got all usecases covered. Please take a look at the patch, I want to commit it as soon as possible. -- Added file: http://bugs.python.org/file39354/with.patch ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Nick Coghlan added the comment: I'm bothered by the remarkable proliferation of new opcodes for the PEP 492 handling. Is there are a specific reason this implicit exception handler can't be decomposed and implemented using the same opcodes as are used to implement explicit exception handlers? -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Roundup Robot added the comment: New changeset 0dc3b61f1dfa by Yury Selivanov in branch 'default': Issue #24017: Plug ref leak. https://hg.python.org/cpython/rev/0dc3b61f1dfa -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Roundup Robot added the comment: New changeset ee7d2c9c70ab by Yury Selivanov in branch '3.4': asyncio: Make sure sys.set_coroutine_wrapper is called *only* when loop is running. https://hg.python.org/cpython/rev/ee7d2c9c70ab New changeset 874edaa34b54 by Yury Selivanov in branch 'default': asyncio: Make sure sys.set_coroutine_wrapper is called *only* when loop is running. https://hg.python.org/cpython/rev/874edaa34b54 -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Yury Selivanov added the comment: Nick, Guido, Updated patch attached. -- Added file: http://bugs.python.org/file39344/await_06.patch ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Nick Coghlan added the comment: Guido convinced me that having StopAsyncIteration inherit from Exception was the right approach, as it means errors are more likely to be of the we caught it when we shouldn't have variety, rather than the harder to debug an exception escaped when it shouldn't have variety. This isn't like SystemExit, KeyboardInterrupt or GeneratorExit where they're specifically designed to reliably terminate a thread of execution. That means I can offer an unreserved +1 on the current patch (#6) for beta 1 :) -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Roundup Robot added the comment: New changeset 3a3cc2b9a1b2 by Yury Selivanov in branch 'default': Issue 24017: Update NEWS file. https://hg.python.org/cpython/rev/3a3cc2b9a1b2 -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Nick Coghlan added the comment: Latest version looks good to me (aside from a quibble about whether StopAsyncIteration should inherit from BaseException instead of Exception - see my review for details). Based on Guido's explanation in the review, I also suggested adding the following example method to the PEP as part of the rationale for StopAsyncIteration: def __anext__(self): try: data = await self._get_data() except EOFError: raise StopAsyncIteration return data The trick is that when __anext__ is itself a coroutine, we really do have 3 exit paths: * suspension to wait for events (await) * returning the next value (return) * terminating iteration (raise StopAsyncIteration) -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Roundup Robot added the comment: New changeset 957478e95b26 by Yury Selivanov in branch '3.4': asyncio: Support PEP 492. Issue #24017. https://hg.python.org/cpython/rev/957478e95b26 New changeset 44c1db190525 by Yury Selivanov in branch 'default': asyncio: Merge 3.4 -- Support PEP 492. Issue #24017. https://hg.python.org/cpython/rev/44c1db190525 -- nosy: +python-dev ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Yury Selivanov added the comment: Guido, Nick, Victor, Thanks for your reviews and guidance! The patch has been committed to the default branch. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Roundup Robot added the comment: New changeset eeeb666a5365 by Yury Selivanov in branch 'default': PEP 0492 -- Coroutines with async and await syntax. Issue #24017. https://hg.python.org/cpython/rev/eeeb666a5365 -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Guido van Rossum added the comment: Thank you Yury! You are a coding machine. On Mon, May 11, 2015 at 8:06 PM, Yury Selivanov rep...@bugs.python.org wrote: Yury Selivanov added the comment: Guido, Nick, Victor, Thanks for your reviews and guidance! The patch has been committed to the default branch. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Changes by Yury Selivanov yseliva...@gmail.com: -- dependencies: +add a Generator ABC ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Yury Selivanov added the comment: New patch is attached. Nick, I think that all of your feedback should be addressed in this patch. Major changes: 1. There are two code flags now: CO_COROUTINE and CO_GENBASED_COROUTINE (I'm OK to use another name, see my older comments). CO_COROUTINE is assigned to all 'async def' code objects. CO_GENBASED_COROUTINE is assigned to generator-based coroutines decorated with types.coroutine(). 2. tp_await renamed to tp_as_async. (I'm OK to use another name, please see my older comment first) PyAsyncMethods struct holds three slots: am_await, am_aiter, am_anext. Implementing am_exit would be tricky, because of how SETUP_WITH opcode is engineered. I'd really prefer to not to add it. 3. collections.abc.Coroutine. 4. etc (all other feedback from you). -- Added file: http://bugs.python.org/file39337/await_05.patch ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Andrew Svetlov added the comment: On Sun, May 10, 2015 at 7:21 PM, Yury Selivanov rep...@bugs.python.org wrote: Yury Selivanov added the comment: Review sent - very nice work on this Yury. Thanks a lot, Nick! Highlights: * I concur with Stefan that we should have a full PyCoroutineMethods struct at the C level, with a tp_as_coroutine pointer to that replacing the current tp_reserved slot Do you think that tp_as_async is a better name? (I explained my point of view in code review comments) Also, do we need slots for __aenter__ and __aexit__? We don't have slots for regular context manager protocol, fwiw. * I also concur with Stefan about adding a Coroutine ABC I will. We definitely need it. * PyType_FromSpec (and typeslots.h) will need updating once we agree on a slot structure (with my recommendation being define C level slots for all of the new PEP 492 methods) * I found CO_COROUTINE/CO_NATIVE_COROUTINE confusing as a reader of the implementation, as they only told me how the objects were defined, rather than telling me why I should care. Based on what I gleaned of their intended purpose from reading the implementation, I suggest switching this to instead use CO_COROUTINE (set for all coroutines, regardless of how they were defined) and CO_ITERABLE_COROUTINE (set only for those coroutines that also support iteration), and adjusting the naming of other APIs accordingly. I agree that CO_COROUTINE is something that we should use for 'async def' functions (instead of CO_NATIVE_COROUTINE). However, CO_ITERABLE_COROUTINE sounds a bit odd to me, as generator-based coroutines (at least in asyncio) aren't supposed to be iterated over. How about CO_GENBASED_COROUTINE flag? Maybe CO_ASYNC_COROUTINE and CO_OLDSTYLE_COROUTINE? This is wild proposal, feel free to ignore it. * I found the names of the WITH_CLEANUP_ENTER and WITH_CLEANUP_EXIT bytecodes misleading, as they don't refer to the corresponding context management phases - they're both related to the exit phase. WITH_CLEANUP_START and WITH_CLEANUP_FINISH should be clearer for readers (both of the implementation and of the disassembled bytecode). Big +1. Your names are much better. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Yury Selivanov added the comment: Review sent - very nice work on this Yury. Thanks a lot, Nick! Highlights: * I concur with Stefan that we should have a full PyCoroutineMethods struct at the C level, with a tp_as_coroutine pointer to that replacing the current tp_reserved slot Do you think that tp_as_async is a better name? (I explained my point of view in code review comments) Also, do we need slots for __aenter__ and __aexit__? We don't have slots for regular context manager protocol, fwiw. * I also concur with Stefan about adding a Coroutine ABC I will. We definitely need it. * PyType_FromSpec (and typeslots.h) will need updating once we agree on a slot structure (with my recommendation being define C level slots for all of the new PEP 492 methods) * I found CO_COROUTINE/CO_NATIVE_COROUTINE confusing as a reader of the implementation, as they only told me how the objects were defined, rather than telling me why I should care. Based on what I gleaned of their intended purpose from reading the implementation, I suggest switching this to instead use CO_COROUTINE (set for all coroutines, regardless of how they were defined) and CO_ITERABLE_COROUTINE (set only for those coroutines that also support iteration), and adjusting the naming of other APIs accordingly. I agree that CO_COROUTINE is something that we should use for 'async def' functions (instead of CO_NATIVE_COROUTINE). However, CO_ITERABLE_COROUTINE sounds a bit odd to me, as generator-based coroutines (at least in asyncio) aren't supposed to be iterated over. How about CO_GENBASED_COROUTINE flag? * I found the names of the WITH_CLEANUP_ENTER and WITH_CLEANUP_EXIT bytecodes misleading, as they don't refer to the corresponding context management phases - they're both related to the exit phase. WITH_CLEANUP_START and WITH_CLEANUP_FINISH should be clearer for readers (both of the implementation and of the disassembled bytecode). Big +1. Your names are much better. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Nick Coghlan added the comment: Review sent - very nice work on this Yury. Highlights: * I concur with Stefan that we should have a full PyCoroutineMethods struct at the C level, with a tp_as_coroutine pointer to that replacing the current tp_reserved slot * I also concur with Stefan about adding a Coroutine ABC * PyType_FromSpec (and typeslots.h) will need updating once we agree on a slot structure (with my recommendation being define C level slots for all of the new PEP 492 methods) * I found CO_COROUTINE/CO_NATIVE_COROUTINE confusing as a reader of the implementation, as they only told me how the objects were defined, rather than telling me why I should care. Based on what I gleaned of their intended purpose from reading the implementation, I suggest switching this to instead use CO_COROUTINE (set for all coroutines, regardless of how they were defined) and CO_ITERABLE_COROUTINE (set only for those coroutines that also support iteration), and adjusting the naming of other APIs accordingly. * I found the names of the WITH_CLEANUP_ENTER and WITH_CLEANUP_EXIT bytecodes misleading, as they don't refer to the corresponding context management phases - they're both related to the exit phase. WITH_CLEANUP_START and WITH_CLEANUP_FINISH should be clearer for readers (both of the implementation and of the disassembled bytecode). -- nosy: +ncoghlan ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Yury Selivanov added the comment: Another iteration: - support of new syntax in lib2to3 - collections.abc.Awaitable -- Added file: http://bugs.python.org/file39325/await_04.patch ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Stefan Behnel added the comment: We also need a Coroutine ABC. Both the GeneratorType and CO_COROUTINE checks are too restrictive. Also see issue 24018, which this one should in fact depend on. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Yury Selivanov added the comment: Third patch attached. Victor, it would be great if you can review it! -- Added file: http://bugs.python.org/file39314/await_03.patch ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Changes by Yury Selivanov yseliva...@gmail.com: -- dependencies: +Missing *-unpacking generalizations ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Changes by Yury Selivanov yseliva...@gmail.com: -- priority: normal - release blocker ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Yury Selivanov added the comment: I'll upload the most recent patch soon. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Guido van Rossum added the comment: I think we can continue this discussion *after* the PEP's been accepted. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Stefan Behnel added the comment: I don't think it's necessary to have slots for __aiter__, __anext__, __aenter__ and __aexit__. Async iteration will never be as fast as regular iteration, and there is plenty overhead in it. You seem to be assuming that the outer loop is the asyncio I/O loop. That might not be the case. It might be a thread-pool executor, it might be an in-memory task switcher, or it might just be something passing on items from a list. At least __anext__ is worth being fast, IMHO. Also note that one advantage of slots is that the user can cache their value to keep calling the same C function multiple times. That is not the case for a Python method, which can easily be replaced. Some iterators do that with their __next__ method, and it's perfectly valid. Having to look up the Python method on each iteration and calling through it sounds like unnecessary overhead. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Changes by Guido van Rossum gu...@python.org: -- nosy: +gvanrossum ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Stefan Behnel added the comment: Could we have type slots for the new special methods? Otherwise, implementing the protocol in C would be fairly inefficient, especially for async iteration. I'm asking because Cython's generator type is not Python's generator type, but implementing the rest of the proposed protocol doesn't seem to be all that difficult. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Yury Selivanov added the comment: In fact I will likely add tp_await in the next PEP iteration. I need it to implement another feature. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Yury Selivanov added the comment: Could we have type slots for the new special methods? Otherwise, implementing the protocol in C would be fairly inefficient, especially for async iteration. I don't think it's necessary to have slots for __aiter__, __anext__, __aenter__ and __aexit__. Async iteration will never be as fast as regular iteration, and there is plenty overhead in it. And we don't need slots for async context managers as we don't have slots for regular ones. What might be a good idea is to add a slot for __await__ method -- tp_await. This will allow to implement Futures in C efficiently. I'd rename 'tp_reserved' for this purpose. Victor, your thoughts? -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Changes by Yury Selivanov yseliva...@gmail.com: -- dependencies: +PEP 479: Change StopIteration handling inside generators ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
STINNER Victor added the comment: Does the implementation depends on the implementation of the PEP 479? (issue #22906) Attaching a patch generated with mercurial Next time, if possible, try to skip generated files. Maybe write a script for that, but sorry I don't know how :-( -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Changes by Yury Selivanov yseliva...@gmail.com: -- assignee: - yselivanov ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Yury Selivanov added the comment: Attaching a revised patch (all Victor's comments but asyncio changes) -- Added file: http://bugs.python.org/file39155/await_02.patch ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Changes by Stefan Behnel sco...@users.sourceforge.net: -- nosy: +scoder type: - enhancement ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Changes by STINNER Victor victor.stin...@gmail.com: -- hgrepos: -306 ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
New submission from Yury Selivanov: Here's the first patch (git diff master..await). Should be easier to review and work from there. -- keywords: +patch stage: - patch review Added file: http://bugs.python.org/file39147/async_01.patch ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Yury Selivanov added the comment: Attaching a patch generated with mercurial -- Added file: http://bugs.python.org/file39148/await_01.patch ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Changes by Yury Selivanov yseliva...@gmail.com: Added file: http://bugs.python.org/file39149/await_01.patch ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Changes by STINNER Victor victor.stin...@gmail.com: -- nosy: haypo priority: normal severity: normal status: open title: Implemenation of the PEP 492 - Coroutines with async and await syntax versions: Python 3.5 ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Changes by STINNER Victor victor.stin...@gmail.com: -- hgrepos: +306 ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Changes by Yury Selivanov yseliva...@gmail.com: -- nosy: +asvetlov, yselivanov ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Changes by Yury Selivanov yseliva...@gmail.com: Removed file: http://bugs.python.org/file39147/async_01.patch ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue24017] Implemenation of the PEP 492 - Coroutines with async and await syntax
Changes by Yury Selivanov yseliva...@gmail.com: Removed file: http://bugs.python.org/file39149/await_01.patch ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue24017 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
