Add docs that TypeVars should be allowed to be the same #8572
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docs/source/common_issues.rst
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| B = TypeVar("B", bound=complex) | ||
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| In some cases, the ``@overload`` decorator can be used to provide the desired type checking. Here's an example. |
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Style nit: write "... an example:" (with a colon)
A simpler workaround would be to cast the default value to the desired type using cast.
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I was able to eliminate the second overload def:
def map_2(queue: Iterable[A], function: Callable[[A], A]) -> Iterable[A]: ...
by using a cast like so:
map_2(list_2, cast(Callable[[B], A], identity))
Is this what you meant?
If so, I would prefer the original approach of keeping the extra overload def so that the actual call is easier to read and to understand.
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Hi, I'm not sure whether this is the workaround that @JukkaL suggested.
def map2(queue: Iterable[B], function: Callable[[B], A] = cast(Callable[[B], A], identity)) -> Iterable[A]: ...
docs/source/common_issues.rst
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| @overload | ||
| def _map2(queue: Iterable[A]) -> Iterable[A]: ... | ||
| @overload | ||
| def _map2(queue: Iterable[A], function: Callable[[A], A]) -> Iterable[A]: ... |
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The second overload item doesn't seem useful, as it's just a special case of the third.
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@JukkaL Thank you for your careful review of this PR. I will be adopting the minor changes and addressing the more substantive ones. Question: what's the process I should follow to make further changes to the branch for this PR? I see that there are a number of different opinions about how to do this. |
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@tz-earl you should make new local commits and push them to your remote branch. Don't force-push or rebase. |
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@JelleZijlstra Thank you for the helpful clarification about more commits |
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Hi! Could you please fix the conflicts? |
97littleleaf11
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97littleleaf11
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Closes #7864.
For the Common Issues and Solutions doc, added a section TypeVars are not the same.
I'm not entirely sure about the example I concocted to show code that does pass muster with Mypy.