RFC on range design for D2

[Brad Roberts]

> Great question. We'll go with structs and duck typing (why the heck
> don't they call it structural typing...) but we'll add interfaces for
> the range types so that they can be used dynamically too. Code
> generation will take care of gluing implementations into classes (more
> on that later).

> Andrei

Probably rhetorical, but I can't help myself:  If it walks like a duck
and it talks like a duck, it must be a duck.