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Title: Unsoundly narrow away from None with custom eq by hauntsaninja · Pull Request #20756 · python/mypy · GitHub

Open Graph Title: Unsoundly narrow away from None with custom eq by hauntsaninja · Pull Request #20756 · python/mypy

X Title: Unsoundly narrow away from None with custom eq by hauntsaninja · Pull Request #20756 · python/mypy

Description: Optional static typing for Python. Contribute to python/mypy development by creating an account on GitHub.

Open Graph Description: With #20754 we see some primer hits where this unsoundness is beneficial Closes #15764

X Description: With #20754 we see some primer hits where this unsoundness is beneficial Closes #15764

Opengraph URL: https://github.com/python/mypy/pull/20756

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Fix bug when narrowing union containing custom eq against custom eq #20754 https://github.com/python/mypy/pull/20754
Better narrowing #20564 https://github.com/python/mypy/issues/20564
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Unsoundly narrow away from None with custom eqhttps://github.com/python/mypy/pull/20756/commits/b8488e153ecf96dc2fdf7b8b317aa9cf1c1aeb7f
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Overriding __eq__ can break Optional/Literal narrowing assumptions #15764 https://github.com/python/mypy/issues/15764
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Overriding __eq__ can break Optional/Literal narrowing assumptions https://github.com/python/mypy/issues/15764
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