Class and Interface Fun

[Tim M]

On Sun, 25 Jan 2009 16:43:55 +1300, John Reimer <terminal.node at gmail.com>  
wrote:

> With this code:
>
> --------------------------------
>
> module test5;
>
> interface I
> {
>     void foo();
> }
>
> class A : I {
>     void foo() { }
> }
>
> class B : A, I
> {
>     alias A.foo foo;
> }
>     void main()
> {
> }
>
> --------------------------------
>
> I get this error:
>
> --------------------------------
>
> class test5.B interface function I.foo is not implemented
>
> --------------------------------
>
> Does this make sense?  I mean, shouldn't the explicit reuse of A.foo in  
> B be sufficient indication to the compiler that B is satisfying the  
> contract I?   I'm hoping to make use of such subtleties in some code,  
> but first I have to understand the reasoning behind this. :)
>
> Note that this works if I remove the interface I from B's declaration --  
> ie "class B: A" -- since, in the D language, B is not required to  
> fulfull A's interface contract even though it inherits from it. -JJR
>
>

It look like the real bug is re-allowing B to implement interface I but  
sometimes bug do get reported differently. Why don't you remove I from B's  
declaration like you said that works. It actually says here  
http://www.digitalmars.com/d/1.0/interface.html "Classes cannot derive  
 from an interface multiple times."