Single "alias this"

[Simen kjaeraas]

Deokjae Lee <asitdepends at gmail.com> wrote:

> Is there any particular reason to disallow multiple "alias this" ?

Yes - the fact that it's not yet implemented. (it's on the drawing board
, just not quite there yet.)


> I can implement "multiple" interfaces and extend "single" base class in
> Java like this:
>
> <code>
> class C extends BaseClass implements Interface1, Interface2, ...
> </code>
>
> But I can't do it using D. Code like the following does not be compiled.
>
> <code>
> class C : BaseClass, Interface1, Interface2, ...
> </code>
>
> Is there any particular reason?

Uhm... That's supposed to work.


> What's the difference between Java's approach and single "alias this"?

Java's (and D's) interfaces is something quite different from alias
this. Alias this is a simplistic (though powerful) kind of subtyping
where the class or struct can embed a different type, and behave as if
it is one, though without polymorphism.

-- 
Simen