Dynamic subclassing ?

[Daniel Nogradi]

> I've got an instance of a class, ex :
>
> b=gtk.Button()
>
> I'd like to add methods and attributes to my instance "b".
> I know it's possible by hacking "b" with setattr() methods. But i'd
> like to do it with inheritance, a kind of "dynamic subclassing",
> without subclassing the class, only this instance "b" !
>
> In fact, i've got my instance "b", and another class "MoreMethods"
>
> class MoreMethods:
>     def  sayHello(self):
>           print "hello"
>
> How could i write ...
>
> "b = b + MoreMethods"
>
> so "b" will continue to be a gtk.Button, + methods/attributs of
> MoreMethods (it's what i call "dynamic inheritance") ...so, things
> like this should work :
>
> - b.set_label("k")
> - b.sayHello()
>
> I can't find the trick, but i'm pretty sure it's possible in an easy
> way.

How about:

class MoreMethods:
    def  sayHello(self):
        print "hello"

class myButton( gtk.Button, MoreMethods ):
    pass

b = myButton( )

isinstance( b, gtk.Button )  # True
b.sayHello( )  # "hello"


Daniel