制作只读描述符

时间:2019-10-21 01:25:08

标签: python python-3.x descriptor python-descriptors

我已经做了一个基本的只读描述符:

class ReadOnlyDescriptor:
    def __init__(self):
        pass
    def __get__(self, obj, objtype=None):
        return obj._something
    def __set__(self, obj, value):
        raise AttributeError("Cannot set this!")
    def __delete__(self, obj):
        raise AttributeError("Cannot delete this!")


class Object:
     something = ReadOnlyDescriptor()
     def __init__(self, something='abc'):
         self._something=something

它在一个基本示例中起作用:

>>> a=Object()
>>> a.something
'abc'
>>> a.something='asdf'
AttributeError: Cannot update this!
>>> del a.something
AttributeError: Cannot delete this!

是否有办法使以上内容更为通用?例如,不必动态地调用obj._something中的__get__来调用它吗?换句话说(除了使用装饰器之外),执行上述操作的更通用方法是什么?

0 个答案:

没有答案