clarify Final reassignment semantics#2241
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carljm
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I think this is a superior rule, but I would be likely to think so, since it's the rule ty already implements 😆
I think this PR needs some improvements, but I'm in favor of the change.
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| else: | ||
| ID3 = 2 # OK | ||
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| ID4: Final[int] # E: not exhaustive assignment |
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I'm not sure I agree that it should be required to enforce exhaustive assignment. Why should this be enforced for a Final name, but not for other names?
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i would expect a type checker to enforce this for all names. but this change is only regarding Final, which to me is even more "static" than normal variables, that a Final name without a value should always be impossible
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https://discuss.python.org/t/clarify-final-assignment/106878