类的装饰器与应用

一切皆对象：

def test():

　　print()

test.x=1

test.y=2

print(test.__dict__)

float  浮点类型

def dec(obj):
    print('123456')
    obj.x=1
    obj.y=2
    obj.z=3
    return obj
@dec    #Foo=dec(Foo)
class Foo:
    pass
print(Foo.__dict__)

类的装饰器

def Typed(**kwargs):
    def dec(obj):
        for k,y in kwargs.items():
           setattr(obj,k,y)
        # obj.__dict__.update(kwargs)
        return obj
    return dec
@Typed(x=1,y=2)
class Foo:
    pass
print(Foo.__dict__)

类的装饰器修订版

class Foo:
    def __init__(self,key,expect_type):
        self.key=key
        self.expect_type=expect_type
    def __set__(self, instance, value):
        print('set方法')
        if not isinstance(value,self.expect_type):
            raise TypeError('错误')
        instance.__dict__[self.key]=value
    def __delete__(self, instance):
        print('delete方法')
    def __get__(self, instance, owner):
        print('get方法')
def Typed(**kwargs):
    def dec(obj):
        for k,y in kwargs.items():
           setattr(obj,k,Foo(k,y))
        # obj.__dict__.update(kwargs)
        return obj
    return dec
@Typed(name=str,age=int)
class Too:
    # name=Foo('name',str)
    # age=Foo('age',int)
    def __init__(self,name,age):
        self.name=name
        self.age=age
t1=Too('林南',29)
t1.name
print(t1.__dict__)

类的装饰器应用