所谓动态继承,是指代码运行时再决定某个类的父类。某些场景下会用到,比如threading.Thread和multiprocessing.Process这两个类有很多同名的接口,可以实现某个子类动态继承这两个类中的某一个,以便测试多线程或多进程的效率问题。
1:使用工厂函数
def createClass(cls): class CustomizedClass(cls): ....... return CustomizedClass ClassList = createClass(list) print(ClassList.__bases__) #prints the parent class names for ClassList instanceClassList = ClassList([1, 2, 3]) #object of ClassList created ClassDict = createClass(dict) print(ClassDict.__bases__) #prints the parent class names for ClassDict instanceClassDict = ClassDict({'a':1, 'b':2}) #object of ClassDict created
2:使用条件表达式
class A: #code for the class A... class B: #code for the class B... class MyClass( A if (condition) else B): #code for the derived class MyClass
参考:
https://www.quora.com/In-Python-is-it-possible-to-decide-which-class-to-inherit-during-runtime
https://stackoverflow.com/questions/21060073/dynamic-inheritance-in-python
https://stackoverflow.com/questions/17599850/dynamically-choosing-class-to-inherit-from