templates

[Steven Schveighoffer]

BLS Wrote:

> On 19/04/2010 20:16, Ellery Newcomer wrote:
> > Hello.
> >
> > Say I have a [struct] template T, which takes a param S.
> >
> > Any T!(S) satisfies a certain template constraint W, so I can use any
> > T!(S) the same way. I want to be able to store heterogeneous T!(S) in a
> > single list. Is there any good way to express the type for this?
> 
> Why not simply...
> 
> class C(O)
> {
>    private O obj;
>    object next;
>    this(O obj)
>    {
>      this.obj = obj;
>    }
>    ...
>    invariant()
>    {
>      assert(this.obj fulfills W);
>    }
>    ...
> }

W is a compile-time interface.  this.obj is Object, so at compile time all you have are Object's methods.

So no, it can't simply be that.

-Steve