On 2012-02-16 20:05, Jonathan M Davis wrote:
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.
Ok, I see. I got the impression that you preferred listeners.
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
Note that I'm saying "overload" not "override".
--
/Jacob Carlborg
