Issue 34175: typing.NamedTuple: type-checking error when "index" used as member (original) (raw)

Issue34175

Created on 2018-07-20 21:08 by campkeith, last changed 2022-04-11 14:59 by admin. This issue is now closed.

Messages (4)
msg322038 - (view)	Author: Keith Campbell (campkeith)	Date: 2018-07-20 21:08
Find the test case below: ---- from typing import NamedTuple class Foo(NamedTuple): alpha: int index: int ---- This results in the following error when run through type-checking with mypy: ---- % mypy --version mypy 0.620 % mypy go.py go.py:5: error: Incompatible types in assignment (expression has type "int", base class "tuple" defined the type as "Callable[[Tuple[int, ...], Any, int, int], int]") ---- When I instantiate this class in the python interpreter, I have no problem accessing the "index" member, so I suspect this is a bug in the type checker.
msg322043 - (view)	Author: Raymond Hettinger (rhettinger) *	Date: 2018-07-21 00:19
> So I suspect this is a bug in the type checker. Perhaps this report should go on the mypy bug tracker rather than the Python language tracker.
msg322045 - (view)	Author: Guido van Rossum (gvanrossum) *	Date: 2018-07-21 00:26
> Perhaps this report should go on the mypy bug tracker rather than the Python language tracker. Agreed. It's up to the OP to file an issue there though (hence adding @campkeith back to the nosy list).
msg322120 - (view)	Author: Keith Campbell (campkeith)	Date: 2018-07-21 18:58
> It's up to the OP to file an issue there though Will do; thanks!