python中的关于mixin的两个例子

参考：https://blog.csdn.net/appleyuchi/article/details/105733270

有时间多看几遍，不难理解

例子1

class Role:
    def walk(self):
       print('走')
 
class RunMixin:
    def run(self):
       print('跑')
 
class PromptSkillMixin:
    def use_prompt_skill(self):
       print('使用了一个瞬发技能')
 
class WalkExMixin:#覆盖Role中的功能，因为下面是最先继承,Role是最后继承
    def walk(self):
       print('疾走')
 
class RoleEx(WalkExMixin, PromptSkillMixin, RunMixin, Role):
 
    def marco(self):
       return [self.run, self.use_prompt_skill]
 
    def use_marco(self):
        print("---------------use_marco技术----------------")
        for action in self.marco():
            action()
        print("－－－－－－－－use_marco结束－－－－－－－－－－")
if __name__ == '__main__':
    r = RoleEx()
 
    r.use_marco()
    r.walk()

输出如下

---------------use_marco技术----------------
跑
使用了一个瞬发技能
－－－－－－－－use_marco结束－－－－－－－－－－－－－－－－－－
疾走

例子2

class Displayer():
    def display(self, message):
        print("--------②这里是Displayer.display函数---start-----")
        print("Displayer的self=", self)
        print(message)
        print("--------②这里是Displayer.display函数---end-----
")


class LoggerMixin():
    def log(self, message, filename='logfile.txt'):
        print("MySubClass self=", self)
        with open(filename, 'a') as fh:
            print("--------③这里是LoggerMixin.log函数---start-----")
            fh.write(message)
            print("--------③这里是LoggerMixin.log函数---end-----
")

    def display(self, message):
        print("display的self=", self)  # 这里的self类指代的是MySubClass,并不是LoggerMixin
        print("------①这里是LoggerMixin的display函数-start--
")
        super().display(message)  # 会调用Displayer.display()函数
        self.log(message)
        print("------①这里是LoggerMixin的display函数-end--
")


class MySubClass(LoggerMixin, Displayer):
    def log(self, message):
        super().log(message, filename='subclasslog.txt')


subclass = MySubClass()
print(MySubClass.__mro__)
subclass.display("This string will be shown and logged in subclasslog.txt")

　　输出如下，使用了魔法函数__mro__, 可以看出复杂类的继承顺序。主要关注LoggerMixin类中display函数里的super().display(message)

(<class '__main__.MySubClass'>, <class '__main__.LoggerMixin'>, <class '__main__.Displayer'>, <class 'object'>)
display的self= <__main__.MySubClass object at 0x0000024EB6FE05F8>
------①这里是LoggerMixin的display函数-start--

--------②这里是Displayer.display函数---start-----
Displayer的self= <__main__.MySubClass object at 0x0000024EB6FE05F8>
This string will be shown and logged in subclasslog.txt
--------②这里是Displayer.display函数---end-----

MySubClass self= <__main__.MySubClass object at 0x0000024EB6FE05F8>
--------③这里是LoggerMixin.log函数---start-----
--------③这里是LoggerMixin.log函数---end-----

------①这里是LoggerMixin的display函数-end--

LoggerMixin