class template specialization and inheritance

[mki]

Hello!

I just discovered the template syntax of D. I am very exited about its simplicity compared to C++.

Now I ran into a template behavior I do not understand. This code:

*** begin code 1 ***
import std.stdio;

class A { }

class B : A { }

class C(T:A) {
    static void tellMe() {
        writefln("derived from A.");
    }
}

class C(T) {
    static void tellMe() {
        writefln("generic.");
    }
}

void main() {
    C!(A).tellMe();
    C!(B).tellMe();
    C!(int).tellMe();
}
*** end code 1 ***

as expected produces the output:

derived from A.
derived from A.
generic.


But this code
*** begin code 2 ***
import std.stdio;

class A(T) { }

class B(T) : A!(T) { }

class C(TT:A!(T)) {
    static void tellMe() {
        writefln("derived from A!(T).");
    }
}

class C(T) {
    static void tellMe() {
        writefln("generic.");
    }
}

void main() {
    C!(A!(int)).tellMe();
    C!(B!(int)).tellMe();
    C!(int).tellMe();
}
*** end code 2 ***

gives the output:
derived from A!(T).
generic.
generic.


In the second line I would expect the output "derived from A!(T)", like in the example of code 1. My feeling is that for C!(B!(int))
'class C(TT:A!(T))'
with TT=B!(T) and T=int should be a better specialization than
'class C(T)'
with T=B!(T).

Why is 'class C(T)' chosen here?

Thanks!

PS:
BTW, I thought hard about the question if there is a way to do similar things in C++, that is to have a specialization of a *class* template which is valid exactly for all classes of a given type A and all classes *derived* from A. For function templates one can use a SFINAE-trick (the 'enable_if' template in boost) to achieve this, but I don't see a way to do this for class templates in C++. Does anyone have an idea?