Generate toString() method at compile time

[Ary Borenszweig]

Hi,

I'd like to generate a toString() method for my classes. For example:
---
import std.stdio;

class Foo {
  int x;
  int y;

  // mixin ...?
}

void main() {
  auto foo = new Foo;
  foo.x = 1;
  foo.y = 2;
  writeln(foo); // prints "Foo(x = 1, y = 2)"
}
---

I tried using getAllMembers, but that also gives me all methods of Foo. 
I just want the fields. I also tried FieldTypeTuple 
(http://dlang.org/phobos/std_traits.html#FieldTypeTuple) but I get that 
gives me the types. And then I can't find anything else in std.traits 
that could help me.

Is this possible?

Thanks,
Ary