Associated types

[BenjyWiener]

I just posted an alternative proposal that would allow for the arbitrary associations you mentioned, I’d love to get your feedback:

`TypeMap`: Generalizing `overload` semantics

Function overloading (via typing.overload) provides the unique and powerful capability of mapping types (and even combinations of types) to other arbitrary types. # Essentially {(str, bytes): bool, (int, bool): tuple[str, float]} @overload def func(x: str, y: bytes) -> bool: ... @overload def func(x: int, y: bool) -> tuple[str, float]: ... Currently, this level of expressiveness is limited to function definitions. I propose generalizing overload mechanics via a new TypeMap special type. Type…