[Zope3-dev] Re: Basic Interfaces question

[Philipp von Weitershausen]

Jim,

> Let's say we have an interface IFoo and an interface IFooExtended
> 
> IFoo defines foo as
> 
> def foo():
>    """do foo"""
> 
> IFooExtended defines foo as
> 
> def foo(myParam=None)
>    """do the same thing as foo in IFoo, except use myParam to extend 
> behavior if available"""
> 
> should IFooExtended descend from IFoo, or should IFooExtended be a 
> different interface?
> 
> i.e., should the definition of IFooExtended be
> 
> class IFooExtended(IFoo):

Usually you would subclass the IFoo interface, but it really depends on 
the meaning you attach to IFooExtended. Are things that are IFooExtended 
also IFoo? Judging by the name IFooExtended, I would think so, but it 
depends on the meaning you want to give it.

Philipp