> thought one problem with not having "proper" inheritance is that this doesn't really help?
> > I meant more about commonality of behaviour. > I think this goes exactly in the direction that I discuss in the last post? I just "assume" for the Abstract versions of the different types how they will behave, and if they don't behave that way, then whoever wrote the extension (likely me anyhow) will need to overload the relevant methods. (?) Thanks, Christoph
