Work around mypy limitations #191
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Currently mypy doesn't interpret things other than classes as being compatible with `Type[T]` (they literally have to be instances of `type`). This makes it hard to properly type the `decode` methods or `Decoder` constructors, as passing type-like-things (e.g. `Union[int, str]`) will error under mypy. `pyright` doesn't have this limitation. For now we add a fallback `overload` to these methods that infers the decoder type as `Decoder[Any]`. This means that `mypy` will no longer error, but will require an explicit annotation to infer the type of the output of `decode`. If/once the `TypeForm` PEP lands, this hack can be removed. Until then `pyright` support for these annotations will be much better than `mypy` support.
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Currently mypy doesn't interpret things other than classes as being compatible with
Type[T](they literally have to be instances oftype). This makes it hard to properly type thedecodemethods orDecoderconstructors, as passing type-like-things (e.g.Union[int, str]) will error under mypy.pyrightdoesn't have this limitation.For now we add a fallback
overloadto these methods that infers the decoder type asDecoder[Any]. This means thatmypywill no longer error, but will require an explicit annotation to infer the type of the output ofdecode.If/once the
TypeFormPEP lands, this hack can be removed. Until thenpyrightsupport for these annotations will be much better thanmypysupport.Fixes #173.