Python 变长泛型类型

Question

是否可以创建访问可变长度参数类型的泛型类型？

基本上，我正在尝试创建一个通用的 observable，用户可以在其中定义他们想要使用类型提示接受的参数。

前任:

Types = TypeVar("Types", var_length=True)

class Obserable(Generic[Types]):

    def subscribe(func: Callable[[Types], None]):
        ...

    def notify(*args: Types):
        ...

def callback(arg1: int, arg2: str, arg3: int) -> None:
    ...

observer: Observable[int, str, int] = Observable()
observer.subscribe(callback)
observer.notify(1, "hello", 5)

Answer 1

据我所知，no . But they plan to add it和 is working on it .
报价:

PEP 484 introduced TypeVar, enabling creation of generics parameterised with a single type. In this PEP, we introduce TypeVarTuple, enabling parameterisation with an arbitrary number of types - that is, a variadic type variable, enabling variadic generics. This enables a wide variety of use cases. In particular, it allows the type of array-like structures in numerical computing libraries such as NumPy and TensorFlow to be parameterised with the array shape, enabling static type checkers to catch shape-related bugs in code that uses these libraries.