python2 怎么继承多个不确定数量的类 - V2EX
推荐学习书目
Learn Python the Hard Way
Python Sites
PyPI - Python Package Index
http://diveintopython.org/toc/index.html
Pocoo
值得关注的项目
PyPy
Celery
Jinja2
Read the Docs
gevent
pyenv
virtualenv
Stackless Python
Beautiful Soup
结巴中文分词
Green Unicorn
Sentry
Shovel
Pyflakes
pytest
Python 编程
pep8 Checker
Styles
PEP 8
Google Python Style Guide
Code Style from The Hitchhiker's Guide
lynn0977

python2 怎么继承多个不确定数量的类

  •  
  •   lynn0977 Oct 23, 2020 2320 views
    This topic created in 2033 days ago, the information mentioned may be changed or developed.
    需求是想继承多个类,但是类的数量不确定。
    对于 python3,可以直接把要继承的类放到一个列表中如 cls,然后按如下的方法继承:
    class NewClass(*cls):
    def __init__(self, *args, **kwargs):
    super().__init__(*args, **kwargs)

    对于 python2.7 按照这个写法好像是不行的,报错了,问一下 python2.7 要如何实现这个目的。
    4 replies    2020-10-23 10:18:41 +08:00
        1
    mec  
       Oct 23, 2020
    啊 这也行,太 magic 了 感觉类的继承最好还是更显式一些吧
    chogath
        2
    chogath  
       Oct 23, 2020
    用装饰器实现不行嘛,你这整的是啥
    Wincer
        3
    Wincer  
       Oct 23, 2020
    Python2 也可以做到,但是比较麻烦:
    1. 首先把 cls 里面的所有类改成新式类;
    2. 使用 type('NewClass', cls, attr) 的方式创建。

    ```
    class A(object):
    pass
    class B(object):
    pass
    class C(object):
    pass

    cls = (A, B, C)

    def init(self, *args, **kwargs):
    super(cls[0], self).__init__(*args, **kwargs)

    type('E', cls, dict(__init__=init)) # 这样可以创建
    >>> __main__.E
    ```

    但是不太建议这么做,,你也看到代码多么复杂了,type 动态创建的类也不好 debug 。
    xiaolinjia
        4
    xiaolinjia  
       Oct 23, 2020
    用 types 函数创建类呗
    NewClass = type('NewClass', tuple(cls), class_attrs)
    About     Help     Advertise     Blog     API     FAQ     Solana     2585 Online   Highest 6679       Select Language
    创意工作者们的社区
    World is powered by solitude
    VERSION: 3.9.8.5 39ms UTC 15:18 PVG 23:18 LAX 08:18 JFK 11:18
    Do have faith in what you're doing.
    ubao msn snddm index pchome yahoo rakuten mypaper meadowduck bidyahoo youbao zxmzxm asda bnvcg cvbfg dfscv mmhjk xxddc yybgb zznbn ccubao uaitu acv GXCV ET GDG YH FG BCVB FJFH CBRE CBC GDG ET54 WRWR RWER WREW WRWER RWER SDG EW SF DSFSF fbbs ubao fhd dfg ewr dg df ewwr ewwr et ruyut utut dfg fgd gdfgt etg dfgt dfgd ert4 gd fgg wr 235 wer3 we vsdf sdf gdf ert xcv sdf rwer hfd dfg cvb rwf afb dfh jgh bmn lgh rty gfds cxv xcv xcs vdas fdf fgd cv sdf tert sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf shasha9178 shasha9178 shasha9178 shasha9178 shasha9178 liflif2 liflif2 liflif2 liflif2 liflif2 liblib3 liblib3 liblib3 liblib3 liblib3 zhazha444 zhazha444 zhazha444 zhazha444 zhazha444 dende5 dende denden denden2 denden21 fenfen9 fenf619 fen619 fenfe9 fe619 sdf sdf sdf sdf sdf zhazh90 zhazh0 zhaa50 zha90 zh590 zho zhoz zhozh zhozho zhozho2 lislis lls95 lili95 lils5 liss9 sdf0ty987 sdft876 sdft9876 sdf09876 sd0t9876 sdf0ty98 sdf0976 sdf0ty986 sdf0ty96 sdf0t76 sdf0876 df0ty98 sf0t876 sd0ty76 sdy76 sdf76 sdf0t76 sdf0ty9 sdf0ty98 sdf0ty987 sdf0ty98 sdf6676 sdf876 sd876 sd876 sdf6 sdf6 sdf9876 sdf0t sdf06 sdf0ty9776 sdf0ty9776 sdf0ty76 sdf8876 sdf0t sd6 sdf06 s688876 sd688 sdf86