# 知识储备： __call__ 方法class Foo: def __call__(self, *args, **kwargs): print(self) print(args) print(kwargs)obj = Foo()obj(1, 2, 3, a=1, b=2, c=3) # obj.__call__(obj,1, 2, 3, a=1, b=2, c=3)# 执行结果：'''<__main__.Foo object at 0x00000221C0280F98>(1, 2, 3){'a': 1, 'b': 2, 'c': 3}'''# 元类内部也应有一个__call__方法，会在调用Foo时触发执行# Foo(1,2,x=1) #Foo.__call__(Foo,1,2,x=1)class Mymeta(type): def __init__(self, class_name, class_bases, class_dic): if not class_name.istitle(): # class_name 首字母不是大写就报类型错误 raise TypeError('类型错误') if '__doc__' not in class_dic or not class_dic['__doc__'].strip(): raise TypeError('必需要有注释且不能为空') super(Mymeta, self).__init__(class_name, class_bases, class_dic) def __call__(self, *args, **kwargs): # obj = Chinese('kingforn',age=18) print(self) # self = Chinese print(args) # args = ('kingforn',) print(kwargs) # kwargs = {'age': 18} # 第一件事：先造一个空对象obj obj = object.__new__(self) # 第二件事：初始化obj self.__init__(obj, *args, **kwargs) # 第三件事：返回obj return objclass Chinese(object, metaclass=Mymeta): # metaclass 元类 """ 这是中国人的类 """ country = 'china' def __init__(self, name, age): self.name = name self.age = age def talk(self): print('%s is talking' % self.name)obj= Chinese('kingforn', age=18)print(obj.__dict__) # 结果：{'name': 'kingforn', 'age': 18}
来源：https://www.cnblogs.com/kingforn/p/11358425.html