Docs: show how to @overload function annotations in user code #2792
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The docs say `@override` doesn't work in user code, but it seems to work in mypy 0.470. The update may be waiting on python#2603, but that PR does not seem to include doc updates, so feel free to put this patch in that PR.
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Hm, it doesn't actually work yet AFAICT. The example you give produces an error for me: So we're still waiting for #2603. Thanks for the contribution though! Once that is in, this will be very helpful. |
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| .. code-block:: python | ||
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| # This is a stub file! | ||
| class Seq(Generic[T], Sequence[T]): |
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Generic[T] here and below are redundant.
| Now if we import ``abs`` as defined in the above library stub, we can | ||
| write code like this, and the types are inferred correctly: | ||
| class Seq(Generic[T], Sequence[T]): | ||
| @overload # These are just for the type checker, and overwritten by the real implementation |
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Such long comments will look a bit ugly on readthedocs. I would recommend wrapping them or shortening to approx. 80 chars.
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OK, I can merge once you approve it. |
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Is it worth adding the information about the order of
but I'm not sure if it's official or undocumented feature; and also whether it's the entire signature needs to be "narrower" or just the argument or return type. |
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Pardon my intervention, I'm superseding this with PR #3159. |
The docs say
@overridedoesn't work in user code, but it seems to work in mypy 0.470.The update may be waiting on #2603, but that PR does not seem to include doc updates,
so feel free to put this patch in that PR.