[Tutor] Changing a class into a subclass

[Kent Johnson]

Ismael Garrido wrote:
> But there's something that I couldn't understand. In the following code, 
> my guess would be that "I'm back from the death" would never get 
> printed... but it is... and twice! Why?

It's printed every time B.pong() is called, just as "Pong" is. You print each one twice - no mystery!

Kent

> 
>  >>> class A:
>    def pong(self):
>        print self.__class__
>        print "Ping!"
>        self.times -=1
>        if self.times >= 0:
>            self.__class__ = B
>            self.pong()
> 
>  >>> class B:
>    def pong(self):
>        print self.__class__
>        print "Pong!"
>        self.times -=1
>        self.__class__ = A
>        self.pong()
>        print "I'm back from the death"
> 
>       >>> a = A()
>  >>> a.times = 3
>  >>> a.pong()
> __main__.A
> Ping!
> __main__.B
> Pong!
> __main__.A
> Ping!
> __main__.B
> Pong!
> __main__.A
> Ping!
> I'm back from the death  ##Weird!
> I'm back from the death
>  >>> a.__class__
> <class __main__.A at 0x00C1AF00>
> 
> 
> Thanks,
> Ismael
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