On Wed, Dec 1, 2021 at 10:50 PM Christopher Barker <python...@gmail.com>
wrote:
> I know this isn't really the place for this conversation, but:
>
>
>> which is what `os.PathLike` represents, hence why `str` isn't covered by
>> it);
>>
>
> wait, what? It seems so clear to me that "PathLike" (as a type specifier)
> would mean: anything that can be passed into os.fspath to give me a path.
> (or, of course to the stdlib functions that take paths)
>
> Isn't the entire purpose of os.fspath that you can write code like:
>
> def fun(some_kind_of_path):
> some_kind_of_path = os.fspath(some_kind_of_path)
>
> (or just pass it to a function you takes PathLIke)
>
> and go on your merry way -- e.g. duck typing, baby!
>
> Is there really no way to annotate that simply now?
>
Assuming you want the return value of 'fun' to be covariant with the path
input, I believe you would say this:
def fun(some_kind_of_path: str) -> str: ...
def fun(some_kind_of_path: bytes) -> bytes: ...
def fun(some_kind_of_path: os.PathLike[AnyStr]) -> AnyStr:
some_kind_of_path = os.fspath(some_kind_of_path)
# transform it
return some_kind_of_path
I would love to be shown how to do this with just a one-line declaration of
'fun', but I've given up trying to figure it out.
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