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Title: Improved `Literal?` types by randolf-scholz · Pull Request #20444 · python/mypy · GitHub

Open Graph Title: Improved `Literal?` types by randolf-scholz · Pull Request #20444 · python/mypy

X Title: Improved `Literal?` types by randolf-scholz · Pull Request #20444 · python/mypy

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

Open Graph Description: This PR aims to formalize the behavior of Literal? types (Instance with last_known_value) by treating them as-if they were AnyOf-types (see python/typing#566) For example, Literal["x"]? i...

X Description: This PR aims to formalize the behavior of Literal? types (Instance with last_known_value) by treating them as-if they were AnyOf-types (see python/typing#566) For example, Literal["x&q...

Opengraph URL: https://github.com/python/mypy/pull/20444

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Dec 19, 2025https://github.com/python/mypy/pull/20444#issue-3748391363
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Specify behavior for Literal? types. #19625https://github.com/python/mypy/issues/19625
meet_types gives unexpected results when meeting literal and Instance #19560https://github.com/python/mypy/issues/19560
Regression: false positive avoid redundant cast with literal union #19055https://github.com/python/mypy/issues/19055
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better support for literal? typeshttps://github.com/python/mypy/pull/20444/commits/0e09a61203c8d3ba8ee91d83f6080cf8dda29a98
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Dec 19, 2025 https://github.com/python/mypy/pull/20444#ref-pullrequest-3300013521
Fix meet_types for literal and instance #19605 https://github.com/python/mypy/pull/19605
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Misleading error message with dict.get like method. (polymorphic function with conflicting context) #20576 https://github.com/python/mypy/issues/20576
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Merge branch 'master' into literals_as_anyof_typeshttps://github.com/python/mypy/pull/20444/commits/6101a57ff5eaf691a519b9e63244186316de0599
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Jan 19, 2026 https://github.com/python/mypy/pull/20444#ref-issue-3696774317
str.split v. LiteralString false positive type error. facebook/pyrefly#1766 https://github.com/facebook/pyrefly/issues/1766
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Merge branch 'master' into literals_as_anyof_typeshttps://github.com/python/mypy/pull/20444/commits/76eb7ceb5b8bec5990f70165b719d39aaa5beea1
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updated test-datahttps://github.com/python/mypy/pull/20444/commits/d7fe6001e6d0e5e26de5d34ceff3d1857522c22c
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fixed incompatibility with FlipFlop test-casehttps://github.com/python/mypy/pull/20444/commits/80d2bed2c79c4ca9e3e1517a2c648172a018e0cd
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added type hint for mypychttps://github.com/python/mypy/pull/20444/commits/96da68d2e4054f33a12bcdb109bddc91fa1f1907
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cleanup + fix meet with NamedTuplehttps://github.com/python/mypy/pull/20444/commits/377a0af66e9eb2deb723beba887a091c802dc5d0
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rewrote ternary statement as separate returns for mypychttps://github.com/python/mypy/pull/20444/commits/cea2af9d6dab1ab5f127bf5a33a0503c2d50a58b
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Merge branch 'master' into literals_as_anyof_typeshttps://github.com/python/mypy/pull/20444/commits/ef22b6911cda2a53763ccf77e801f657adc8c641
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explicit is None check for mypychttps://github.com/python/mypy/pull/20444/commits/f2b855c2c651e23a1c6f5102b00ee41544060d3c
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Merge branch 'master' into literals_as_anyof_typeshttps://github.com/python/mypy/pull/20444/commits/8d53181adf7563fc0222924b0caa838bc3c3560c
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Remove list.__add__ overloads. python/typeshed#14282 https://github.com/python/typeshed/pull/14282
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Merge branch 'master' into literals_as_anyof_typeshttps://github.com/python/mypy/pull/20444/commits/8dfa9d68d2cc94b4ea4962b390753de1d5f136ab
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Merge branch 'master' into literals_as_anyof_typeshttps://github.com/python/mypy/pull/20444/commits/da5727b2d632ebfdc0626c6e8ab4256f4484530f
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Specify behavior for Literal? types. https://github.com/python/mypy/issues/19625
meet_types gives unexpected results when meeting literal and Instance https://github.com/python/mypy/issues/19560
Regression: false positive avoid redundant cast with literal union https://github.com/python/mypy/issues/19055
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Privacyhttps://docs.github.com/site-policy/privacy-policies/github-privacy-statement
Securityhttps://github.com/security
Statushttps://www.githubstatus.com/
Communityhttps://github.community/
Docshttps://docs.github.com/
Contacthttps://support.github.com?tags=dotcom-footer

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URLs of crawlers that visited me.