Mixin 是利用语言特性来简洁的实现组合模式，Python 中通过一定规范的多继承实现的。
使用时需要注意一下几点：
- 类的单一职责
- 对宿主类一无所知
- 不存在对宿主类的方法调用，避免引入 MRO 查找顺序
如下例子，对于不同的 Mixin 类只负责实现自己的行为特征函数，然后 People 类继承这些特征，在自己的函数中使用这些特征。
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| #!/usr/bin/python
# coding: utf-8
"""
File: mixin_demo.py
Author: noogel <noogel@163.com>
Date: 2018-01-12 09:11
Description: mixin_demo
"""
class EatMixin(object):
def eat(self):
return "eat!"
class DrinkMixin(object):
def drink(self):
return "drink!"
class SleepMixin(object):
def sleep(self):
return "sleep!"
class People(EatMixin, DrinkMixin, SleepMixin):
def __init__(self):
print "People can ", self.eat()
print "People can ", self.drink()
print "People can ", self.sleep()
if __name__ == "__main__":
print "Init people."
people = People()
|
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| ➜ dev-demo python mixin_demo.py
Init people.
People can eat!
People can drink!
People can sleep!
|
https://www.zhihu.com/question/20778853
