class A (object):
keywords = ('one', 'two', 'three')
class B (A):
keywords = A.keywords + ('four', 'five', 'six')
有没有办法将A.keywords
更改为<thing B derives from>.keywords
,有点像super()
,但有点__init__/self
?我不喜欢在定义中重复类名。
用法:
>>> A.keywords
('one', 'two', 'three')
>>> B.keywords
('one', 'two', 'three', 'four', 'five', 'six')
答案 0 :(得分:5)
实际上,你可以。编写一个descriptor来检查类的基础,查找具有相同名称的属性,并将传递的属性添加到其值中。
class parentplus(object):
def __init__(self, name, current):
self.name = name
self.value = current
def __get__(self, instance, owner):
# Find the attribute in self.name in instance's bases
# Implementation left as an exercise for the reader
class A(object):
keywords = ('one', 'two', 'three')
class B(A):
keywords = parentplus('keywords', ('four', 'five', 'six'))
答案 1 :(得分:1)
是。只要你已经开始上课,就使用__bases__ attr查找基类。否则你需要改变方法,因为B不知道它的父母。
class A (object):
keywords = ('one', 'two', 'three')
class B (A):
def __init__(self):
keywords = self.__bases__[0].keywords + ('four', 'five', 'six')
答案 2 :(得分:1)
使用元类:
#!/usr/bin/env python
# -*- coding: utf-8 -*-
class Meta(type):
def __new__(cls, name, bases, attrs):
new_cls = super(Meta,cls).__new__(cls, name, bases, attrs)
if hasattr(new_cls, 'keywords'):
new_cls.keywords += ('1','2')
return new_cls
class B(object):
keywords = ('0',)
__metaclass__= Meta
def main():
print B().keywords
if __name__ == '__main__':
main()
答案 3 :(得分:0)
我发现了一种解决方法式解决方案,无需额外的类和defs就能为我工作。
class BaseModelAdmin(admin.ModelAdmin):
_readonly_fields = readonly_fields = ('created_by', 'date_add', 'date_upd', 'deleted')
和子类化时
class PayerInline(BaseTabularInline):
exclude = BaseTabularInline._exclude + ('details',)
希望这有帮助。