[Python-3000] Abilities / Interfaces

[Phillip J. Eby]

At 06:29 PM 11/22/2006 -0200, Gustavo Niemeyer wrote:
>Without interfaces, we won't be able to say "in all places, use the
>generic method registered for an IFruit whenever an Apple is seen".

...for some definition of "interface".  :)

Dylan has "protocols", Haskell has "typeclasses", and they do what you're 
describing.  The term "interface" in this discussion has been heavily 
linked to Java/Zope-style interfaces, however, as opposed to these other 
styles of "interface".  To be clear, I'm opposing a particular style most 
commonly associated with the word "interface", *not* to the idea of having 
some way to describe a multitude of types.