I was wondering if every use of 'await' should return the control to event loop? So in this example - https://gist.github.com/caulagi/3edea8cf734495f2592528a48f99e1d2 - I was hoping I would see 'A', 'B' to be mixed, but I see only 'A' followed by 'B'. What am I missing? I am using Python 3.7.1. How is my example different from https://docs.python.org/3.7/library/asyncio-task.html#asyncio.run? Thanks.
No, in this case fib(1) is resolved instantly, thus it's caller is resolved instantly, thus... On Mon, 10 Dec 2018 at 9:28 PM, Pradip Caulagi <caulagi@gmail.com> wrote:
I was wondering if every use of 'await' should return the control to event loop? So in this example - https://gist.github.com/caulagi/3edea8cf734495f2592528a48f99e1d2 - I was hoping I would see 'A', 'B' to be mixed, but I see only 'A' followed by 'B'. What am I missing? I am using Python 3.7.1.
How is my example different from https://docs.python.org/3.7/library/asyncio-task.html#asyncio.run?
Thanks. _______________________________________________ Async-sig mailing list Async-sig@python.org https://mail.python.org/mailman/listinfo/async-sig Code of Conduct: https://www.python.org/psf/codeofconduct/
Yeah, 'await' makes it *possible* for the function you're calling to return control to the event loop, but returning is still an explicit action that the function has to take. In asyncio, the only operation that actually returns control to the event loop is awaiting a Future object. In Trio, we make a documented guarantee that all the async functions in the 'trio' namespace do in fact return control to the event loop (we call this a "checkpoint"). In both cases, the effect is the same: if a function never actually awaits a Future/calls one of Trio's built-in async functions, either directly or indirectly, then it won't return to the event loop. (And curio actually has a number of primitives that you call with await, and that do in fact return to the event loop, but that still don't actually let other tasks run, which I found pretty confusing. This is one of the major reasons I stopped using curio.) -n On Mon, Dec 10, 2018, 04:32 Dima Tisnek <dimaqq@gmail.com wrote:
No, in this case fib(1) is resolved instantly, thus it's caller is resolved instantly, thus...
On Mon, 10 Dec 2018 at 9:28 PM, Pradip Caulagi <caulagi@gmail.com> wrote:
I was wondering if every use of 'await' should return the control to event loop? So in this example - https://gist.github.com/caulagi/3edea8cf734495f2592528a48f99e1d2 - I was hoping I would see 'A', 'B' to be mixed, but I see only 'A' followed by 'B'. What am I missing? I am using Python 3.7.1.
How is my example different from https://docs.python.org/3.7/library/asyncio-task.html#asyncio.run?
Thanks. _______________________________________________ Async-sig mailing list Async-sig@python.org https://mail.python.org/mailman/listinfo/async-sig Code of Conduct: https://www.python.org/psf/codeofconduct/
_______________________________________________ Async-sig mailing list Async-sig@python.org https://mail.python.org/mailman/listinfo/async-sig Code of Conduct: https://www.python.org/psf/codeofconduct/
While on the subject of referenced documentation, I find that it too conflates concurrency with parallelism. I don't have a good fix in mind though. Any takers?
Thanks Nathaniel, Dima! On Mon, Dec 10, 2018 at 7:45 PM Nathaniel Smith <njs@pobox.com> wrote:
Yeah, 'await' makes it *possible* for the function you're calling to return control to the event loop, but returning is still an explicit action that the function has to take.
In asyncio, the only operation that actually returns control to the event loop is awaiting a Future object.
In Trio, we make a documented guarantee that all the async functions in the 'trio' namespace do in fact return control to the event loop (we call this a "checkpoint").
In both cases, the effect is the same: if a function never actually awaits a Future/calls one of Trio's built-in async functions, either directly or indirectly, then it won't return to the event loop.
(And curio actually has a number of primitives that you call with await, and that do in fact return to the event loop, but that still don't actually let other tasks run, which I found pretty confusing. This is one of the major reasons I stopped using curio.)
-n
On Mon, Dec 10, 2018, 04:32 Dima Tisnek <dimaqq@gmail.com wrote:
No, in this case fib(1) is resolved instantly, thus it's caller is resolved instantly, thus...
On Mon, 10 Dec 2018 at 9:28 PM, Pradip Caulagi <caulagi@gmail.com> wrote:
I was wondering if every use of 'await' should return the control to event loop? So in this example - https://gist.github.com/caulagi/3edea8cf734495f2592528a48f99e1d2 - I was hoping I would see 'A', 'B' to be mixed, but I see only 'A' followed by 'B'. What am I missing? I am using Python 3.7.1.
How is my example different from https://docs.python.org/3.7/library/asyncio-task.html#asyncio.run?
Thanks. _______________________________________________ Async-sig mailing list Async-sig@python.org https://mail.python.org/mailman/listinfo/async-sig Code of Conduct: https://www.python.org/psf/codeofconduct/
_______________________________________________ Async-sig mailing list Async-sig@python.org https://mail.python.org/mailman/listinfo/async-sig Code of Conduct: https://www.python.org/psf/codeofconduct/
participants (3)
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Dima Tisnek -
Nathaniel Smith -
Pradip Caulagi