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[Python-Dev] Error in Python Tutorial on Multiple Inheritence

Anthony Baxter anthony at interlink.com.au
Fri Aug 13 10:15:07 CEST 2004 
Steven Kah Hien Wong wrote:
>     class CommonBase:
>         x = 0
> 
>     class ChildOne(CommonBase):
>         None
> 
>     class ChildTwo(CommonBase):
>         None
> 
>     class ChildOneAndTwo(ChildOne, ChildTwo):
>         def run(self):
>             ChildOne.x = 1
>             print "one =", ChildOne.x
>             print "two =", ChildTwo.x
> 
>     ChildOneAndTwo().run()
> 
> And the output was:
> 
>     $ python multi.py
>     one = 1
>     two = 0
> 
> According to the documentation, I thought it should be:
> 
>     one = 1
>     two = 1

Nope. In the code, you set a new attribute 'x' on the ChildOne
class.

Change the end of your code to
ChildOneAndTwo().run()
print "CommonBase.x", CommonBase.x
print "ChildOne.x", ChildOne.x
print "ChildTwo.x", ChildTwo.x

Anthony
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