Add support for PEP 567 context variables to tasklets

[akruis]

Python 3.7 added the context variables and the module contextvars. See PEP 567 for details.

Using tasklets it is possible to decorate a plain old callable as a coroutine (and vice versa). To make such a coroutine fully compatible with C-Python asyncio tasklets should support PEP 567 context variables. In C-Python the current context is a property of the thread state, that is, each thread has its own current context. In Stackless Python a thread can have multiple tasklets. Therefore the current context must become a property of the tasklet.

I'm still elaborating details.

[kristjanvalur]

+1 sun., 18. apr. 2021 kl. 20:02 skrifaði Anselm Kruis < ***@***.***>:

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Python 3.7 added the context variables and the module *contextvars*. See PEP 567 <https://www.python.org/dev/peps/pep-0567> for details. Using tasklets it is possible to decorate a plain old callable as a coroutine (and vice versa). To make such a coroutine fully compatible with C-Python asyncio tasklets should support PEP 567 context variables. In C-Python the *current context* is a property of the thread state, that is, each thread has its own *current context*. In Stackless Python a thread can have multiple tasklets. Therefore the *current context* must become a property of the tasklet. I'm still elaborating details. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#239>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABN3FR3YUENJVFAUOKQSMCLTJM3EDANCNFSM43ESA4RA> .

[akruis]

First usable code is in https://github.com/akruis/cpython/tree/slp37 (a71d969f06). It is still work in progress.
And here is the project, that needs the contextvar support https://github.com/akruis/slp_coroutine. This project is also work in progress.

[akruis]

Implemented in 3.7-slp

[akruis]

Merged into main-slp.