On Thursday, February 16, 2012 13:26:59 Jacob Carlborg wrote: > Since D have delegates I would use those for event handling and not > listeners. I think they are a much better fit, as long as you don't have > to force the user to handle many different events on the same object.
Oh, I'm not necessarily arguing that using interfaces far listeners is the way to go (in fact, I agree that delegates would be much better). It's just that that's a prime example of a situation where you want default implementations for interface methods, since with single inheritance, you can't derive a class from multiple classes which give you default implementations for interface methods. > > Now, if you use template mixins, I believe that it's possible to use that > > to mixin default implementations for the functions in an interface, which > > should solve the problem for D. So, that's probably good enough for D > > without having to make it so that interface functions can have default > > implementations. > > Template mixins cause their own problems. You can't overload methods > with template mixins, may it's possible to get around that with aliases, > I don't remember. I thought that you could, since they can be virtual, unlike templated functions. I don't know though. It's not something that I've really had to worry about - particularly since so few of my D programs need classes, let alone interfaces (because most of my D programs are small). - Jonathan M Davis
