Python mutiple-inherit code instance

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class A:def __init__(self):print("Enter A")print("Leave A")class B(A):def __init__(self):print("Enter B")A.__init__(self)print("Leave B")class C(A):def __init__(self):print("Enter C")A.__init__(self)print("Leave C")class D(A):def __init__(self):print("Enter D")A.__init__(self)print("Leave D")class E(B, C, D):def __init__(self):print("Enter E")B.__init__(self)C.__init__(self)D.__init__(self)print("Leave E")E()

输出结果：

Enter E
Enter B
Enter A
Leave A
Leave B
Enter C
Enter A
Leave A
Leave C
Enter D
Enter A
Leave A
Leave D
Leave E

class A:def __init__(self):print("Enter A")print("Leave A")class B(A):def __init__(self):print("Enter B")super(B, self).__init__()print("Leave B")class C(A):def __init__(self):print("Enter C")super(C, self).__init__()print("Leave C")class D(A):def __init__(self):print("Enter D")super(D, self).__init__()print("Leave D")class E(B, C, D):def __init__(self):print("Enter E")super(E, self).__init__()print("Leave E")E()

输出结果：

Enter E
Enter B
Enter C
Enter D
Enter A
Leave A
Leave D
Leave C
Leave B
Leave E

在super机制里可以保证公共父类仅被执行一次，至于执行的顺序，是按照mro进行的（E.__mro__）。

参考资料：

http://blog.csdn.net/u010069176/article/details/51734338

http://www.cnblogs.com/dkblog/archive/2011/02/24/1980654.html

自定义异常：http://blog.sina.com.cn/s/blog_151a5b5330102wqsg.html

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