Bug in D?!

[Mr. Pib via Digitalmars-d-learn]

string Q(alias T, alias D)()
{
        pragma(msg, T);
        pragma(msg, D);
        enum x = T~" = "~D~";";
        pragma(msg, x);
}

mixin(Q!(`x`, 100)());

outputs, at compile time,

x
100
x = d;

there is no lowercase d. I did initially define Q as

string Q(alias T, D)(D d)

and one might think it is remnants left over from I cleaned the 
project so it shouldn't be happening. Seems like a bug.

(I realized that I'd probably only ever pass compile time values)

Of course, using D.stringof gives the value.

The problem is the case of D.