初始化Python类中的静态字段

失败的原因是 explained here .

你可以通过定义 foo 通过 class decorator add_foo 调用时,类已定义并 _init_foo 然后作为 cls._init_foo :

def add_foo(cls):
    cls.foo = { cls._init_foo() for i in range(10) }
    return cls

@add_foo
class Test:

    def _init_foo(): return 3


print(Test.foo)
# {3}

class Box:

    def __init__(self, x):
        self.x = x
        Box.count += 1  # static field usage

    @staticmethod
    def instance_count():
        return Box.count  # static field usage

Box.count = 0  # static field initialisation

b1 = Box(10)
b2 = Box(20)
print(Box.count)  # 2