Why can't structs be derived from?

[Andrej Mitrovic]

On 3/17/11, Nick Sabalausky <a at a.a> wrote:
> I've long been convinced that "alias old new;" should really be "alias new =
> old;" The current way confuses me, and I *still* have to consciously stop
> and think about it every time I write an alias statement (including just
> now).
>

I thought I was the only one. The `alias symbol this` in structs in
particular always stops me and I have to think about what it means,
even though it might be obvious.