Where does "U" in Rebindable.Rebindable come from?

[Philippe Sigaud]

On Fri, Mar 30, 2012 at 01:09, Simen Kjærås <simen.kjaras at gmail.com> wrote:
> The same pattern is used in std.typecons.isTuple:
>
> template isTuple(T)
> {
>    static if (is(Unqual!T Unused : Tuple!Specs, Specs...))
>    {

Wait, does that work now? They added 'is(XXX, YYY...)'?