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Title: No type variables left in
Type: crash Stage: resolved
Components: Versions: Python 3.9
Status: closed Resolution: fixed
Dependencies: Superseder:
Assigned To: Nosy List: kj, tyler.yep
Priority: normal Keywords:

Created on 2021-01-22 20:13 by tyler.yep, last changed 2022-04-11 14:59 by admin. This issue is now closed.

Messages (3)
msg385511 - (view) Author: Tyler Yep (tyler.yep) Date: 2021-01-22 20:13
The following code crashes when I try to run it, even though it passes when I use `from typing import Callable` instead.

from import Callable
from typing import Any, TypeVar

V = TypeVar("V")
Function = Callable[[list[V], V, V], float]

def random_fn(fn: Function[Any]) -> Function[Any]:
    return fn
msg385521 - (view) Author: Ken Jin (kj) * (Python committer) Date: 2021-01-23 04:01
This seems to be a duplicate of Issue40494. It has already been fixed in Python 3.10, and in Python 3.9.2 (which isn't out yet). You can see the what's new for it here

The expected release date for Python 3.9.2 is Monday, 2021-02-15 according to PEP 596

For now, I guess you'll have to use the old typing.Callable, then update it in newer versions of Python.

I'm assuming you are currently using python 3.9.0/3.9.1, which has this bug. I'm unable to reproduce it on Python 3.10.
msg385522 - (view) Author: Tyler Yep (tyler.yep) Date: 2021-01-23 04:12
Got it, thanks!
Date User Action Args
2022-04-11 14:59:40adminsetgithub: 87170
2021-01-23 04:12:23tyler.yepsetstatus: open -> closed
resolution: fixed
messages: + msg385522

stage: resolved
2021-01-23 04:01:46kjsetmessages: + msg385521
2021-01-22 23:19:42gvanrossumsetnosy: + kj
2021-01-22 20:13:42tyler.yepcreate