""" Tests basic usage of ParamSpec. """ # Specification: https://typing.readthedocs.io/en/latest/spec/generics.html#paramspec-variables from typing import Any, Callable, Concatenate, ParamSpec, TypeAlias P = ParamSpec("P") # OK WrongName = ParamSpec("NotIt") # E: name inconsistency # > Valid use locations TA1: TypeAlias = P # E TA2: TypeAlias = Callable[P, None] # OK TA3: TypeAlias = Callable[Concatenate[int, P], None] # OK TA4: TypeAlias = Callable[..., None] # OK TA5: TypeAlias = Callable[..., None] # OK def func1(x: P) -> P: # E raise NotImplementedError def func2(x: Concatenate[int, P]) -> int: # E raise NotImplementedError def func3(x: list[P]) -> None: # E ... def func4(x: Callable[[int, str], P]) -> None: # E ... def func5(*args: P, **kwargs: P) -> None: # E ...