On Oct 28, 1:16 am, Pradeep Jindal <[EMAIL PROTECTED]> wrote: > On Friday 26 Oct 2007 6:21:57 pm Anand wrote: > > > > > On Oct 26, 5:31 pm, "Pradeep Jindal" <[EMAIL PROTECTED]> wrote: > > > Can you tell any specific use case for doing this? > > > I have many implementaions of a db interface. > > > SimpleDB - simple implementation > > BetterDB - optimized implementation > > CachedDB - an implementation with caching of queries > > RestrictedDB - implementation with permissions > > > Now, I want to combine these implementations and use. > > Typical use case scenarios are: > > > db = RestrictedDB(CachedDB(SimpleDB())) > > db = RestrictedDB(SimpleDB()) > > db = RestrictedDB(BetterDB()) > > db = RestrictedDB(CachedDB(BetterDB()) > > db = CachedDB(SimpleDB()) > > etc.. > > I agree with Duncan. According to me, this should be called Delegation rather > than inheritance. And delegation should work without any conflicts of > identifier names and all that. I think, it should be all about several > objects implementing a protocol (interface) and that should work cleanly.
I don't think so. It is not as simple as delegation. In the example that I gave previously, call to self.say in A.foo calls B.say not A.say, which I think is not possible with delegation. -- http://mail.python.org/mailman/listinfo/python-list
