On Sun, Jun 27, 2010 at 6:47 PM, Shashwat Anand <anand.shash...@gmail.com> wrote: > <snip> >> >> The problem of the MRO isn't that it doesn't work, it's that it causes >> behavior that is unintuitive. In my example, We would expect D.x to be >> equal to C.x (since D inherits from C, and C overrides the x method). >> However, this is not the case. This is what the problem is with the >> old MRO system, not so much that it doesn't work at all, but the >> results aren't consistent with what you'd expect from multiple >> inheritance. >> > > I tried your example in python2.6 >>>> class A: > ... def x(self): return "in A" > ... >>>> class B(A): pass > ... >>>> class C(A): > ... def x(self): return "in C" > ... >>>> class D(B, C): pass > ... >>>> o = D() >>>> o.x() > 'in A' > If MRO was in python2.3, the output of o.x() should be 'in C'. It works fine > on 3.2alpha though. >
You forgot that the example as is still uses the old MRO, even in 2.3. This is because these classes are still classic-style classes. To use the new MRO you will have to use new-style classes (A must inherit from object). In 3.x it will of course work fine, since everything without explicit inheritance inherits from object. Hugo _______________________________________________ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
