Question

我正在创建一个抽象类，我希望其所有继承都保存一个具有确切名称的X类型对象。

查看示例：

from abc import ABC, abstractmethod

class Hands(object):
    pass

class human(ABC):

    def __init__(self):

        self.hand=Hands()

        @property
        def Hands(self):
            pass

class american_hands(Hands):
    pass


#I want to make sure that a class of type human will have a member of type hands which is called hand
class american(human):

    def __init__(self):
        self.hand=american_hands()

如何强制人类类的后代持有具有预定义名称的所需类型的成员？

例如，我希望没有class.hand.self.hand的实现类human的任何人都会引发错误，例如：

class German(Human):
    def __init__(self):
        super().__init__()

不行。

Answer 1

也许类似

class Hands:
    pass


class AmericanHands(Hands):
    pass


class Human:
    hand_type = Hands

    def __init__(self):
        self.hands = self.hand_type()


class American(Human):
    hand_type = AmericanHands

    def __init__(self):
        super().__init__()
        # Other American-specific initialization


h = Human()  # assert isinstance(h.hands, Hands)
a = American()  # assert isinstance(a.hands, AmericanHands)

对super().__init__的调用可确保American的实例具有名为hands的属性，而override class属性可确保hands的类型正确。 / p>

强制持有常量名称类型的对象的抽象类

1 个答案: