键入几个类中的一个

Question

假设我有以下两门课：

class Literal:
    pass

class Expr:
    pass

class MyClass:
    def __init__(self, Type:OneOf(Literal, Expr)):
        pass

如何使类型成为Expr或Literal类之一？我想要做的事情的全部例子如下：

from enum import Enum
PrimitiveType = Enum('PrimitiveType', ['STRING', 'NUMBER'])

class Array:
    def __init__(self, Type:OneOf[Array,Struct,PrimitiveType]):
        self.type = Type

class Pair:
    def __init__(self, Key:str, Type:OneOf[Array,Struct,PrimitiveType]):
        self.Key = Key
        self.Type = Type

class Struct:
    def __init__(self, tuple[Pair])

Answer 1

您需要一个Union类型：

from typing import Union

def __init__(self, Key: str, Type: Union[Array, Struct, PrimitiveType]):

# or in 3.10+

def __init__(self, Key: str, Type: Array | Struct | PrimitiveType):

Answer 2

您可以参考post：How to express multiple types for a single parameter or a return value in docstrings that are processed by Sphinx?

from typing import Union

和

def __init__(self, Type:Union[Array,Struct,PrimitiveType])