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pthon: 动态地将属性添加到已建班级
原标题:python: dynamically adding attributes to a built-in class

为什么不为建班工作?

是否采用次等处理方法,还是我会遇到一些隐蔽的问题?

a = {}
a.p = 1 # raises AttributeError
class B(dict):
  pass
b = B()
b.p = 1 # works

EDIT:我的原始评论是,它没有为<代码>b做任何工作是不正确的(我犯了一个错误)。

最佳回答

教学课程不具备任意特性的能力。 由于业绩原因,特别是记忆的使用,你希望像<条码>>>>>>、<条码>和<条码>/代码”等已建班尽可能少,以便你能够拥有其中很多。

Therefore the built-in classes do not have the __dict__ dictionary that is needed for arbitrary attributes to work.

你们的班子可以实现同样的目标。 如在C中写成,你根本不执行<条码>第__条令/条码>支持。 如果写在Zalze的

问题回答

If you want to subclass dict you can always use UserDict (here the documentation).

它与你一起努力:

from collections import UserDict

a = UserDict()
a.p = 10 # works fine




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