Documentation: type[BaseClass] accepting subclasses
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bug
topic-mypyc
- Dominant language
- Python
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Description
Documentation
class BaseClass: pass
class Child1(BaseClass): pass
list[type[BaseClass]] = [BaseClass, Child1]
- MyPy strict has not issues
- MyPyC compiled fine
- But running with MyPyc raises a
TypeError: BaseClass expected; got Child1
A. Is there a documentation for this case? or is it an issue?
B. What is the solution for this? Can MyPyC read typing.cast to disable this strict mode?
like [BaseClass, typing.cast(BaseClass, Child1)] ?
C. I saw some TypeVar(bound='') solution but didn't work here.
D. Or do I need to just set as typing.Any to avoid issues?
- Python 3.14
- MyPy: 1.18.2
Thanks in advance
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Research direction
Start with the Python reproducer in the issue and compare its behavior under MyPy and MyPyC. Determine whether the subclass rejection is expected, a bug, or a documentation gap, and make the supported solution clear, including whether typing.cast or Any is appropriate.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- python
- Domain
- compilers, devtools
- Issue type
- Documentation
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Stale
- Clarity
- Needs clarification
- Newbie friendliness
- 25/100