March 03, 2008
Templates, traits, mixins, and meta programming I haven't really gotten into. But I came to note that templating inheritance of a class works great.

http://dsource.org/projects/tutorials/wiki/TemplatedInheritanceExample

My question is what others think about the possibility of using traits from D2.0 to allow for interface instantiation without reimplementing methods? I don't know how practical it would be but it might be quite interesting.
March 03, 2008
Jesse Phillips wrote:
> Templates, traits, mixins, and meta programming I haven't really gotten into. But I came to note that templating inheritance of a class works great.
> 
> http://dsource.org/projects/tutorials/wiki/TemplatedInheritanceExample
> 
> My question is what others think about the possibility of using traits from D2.0 to allow for interface instantiation without reimplementing methods? I don't know how practical it would be but it might be quite interesting.

I have an example, and a usable one, that basically proxies a class or interface using templated inheritance. It doesn't quite support concrete classes right now, because I want a reliable solution, and a concrete class could define a constructor that throws an exception or dereferences a null pointer or some such. All the virtual methods for the concrete class will be properly proxied; it's just that you depend on the constructor to work correctly.

The code's here:
http://www.dsource.org/projects/dmocks/browser/trunk/dmocks/dmocks/MethodMock.d
http://www.dsource.org/projects/dmocks/browser/trunk/dmocks/dmocks/MockObject.d

Not really that difficult. How it applies to your question isn't quite clear, though; you want your interface methods to do something useful. The typical tactic with that is to define a mixin with default implementations. Works best if you do that with an abstract base class and then override whatever you need to, I think.