Thanks for your reply Jean-Daniel. >> I can see two ways of working around this - either implement placeholder >> methods in the base class (that raise an exception or something) in order to >> make the base class conform to the protocol (knowing that in practice they >> should always be overridden by a subclass), or have the subclass pass its >> "self" pointer to the base class in the form of an id<MyProtocol> that the >> base class uses when it needs to call such methods. Both of these leave me >> feeling pretty dirty, though. > Adding stub methods that raise an exception seam a good way to solve the > problem (that what all class cluster abstract class do in Cocoa Framework).
The reason I wasn't wild on this is that it stops me getting compile-time warnings saying that the protocol is not fully implemented (since the base class fully implements it). There will be run-time errors when the non-overridden base class stub is hit. Maybe that's the best of the available choices, though. I just hoped there would be a "proper" way around this. I'm sure the language designers are far smarter than me and had good reasons for what they did, but I do miss abstract base classes! Cheers Jonny_______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
