python学习之类装饰器应用和数据描述符相结合

def deco(**kwargs):
   def wrapper(obj):
      for key, val in kwargs.items():
         setattr(obj, key, Typed(key, val))
      return obj

   return wrapper


class Typed:
   def __init__(self, key, expected_type):
      self.key = key
      self.expected_type = expected_type

   def __get__(self, instance, owner):
      return instance.__dict__[self.key]

   def __set__(self, instance, value):
      if not isinstance(value, self.expected_type):
         raise TypeError('%s 传入的类型不是%s' % (self.key, self.expected_type))
      instance.__dict__[self.key] = value

   def __delete__(self, instance):
      pass


@deco(name=str, age=int, gender=str, height=int)
class People:
   def __init__(self, name, age, gender, height):
      self.name = name
      self.age = age
      self.gender = gender
      self.height = height


p1 = People('alan', 18, 'boy', 185)
print(People.__dict__)

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<__main__.lazyproperty object at 0x0000000002933320> 实例
<__main__.Room object at 0x0000000002933390> 实例
<class '__main__.Room'> 类
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