Metaprogramming with traits

[Ram_B via Digitalmars-d-learn]

How i can get fields of derived classes in runtime? This not works

import std.traits;
import std.experimental.logger;


class A {
        int a,b;
        this(){}
        void fields(){
                log(FieldNameTuple!this);       
        }
}

class B : A{
        int c;
        this(){}
}

void main(){
        B b = new B();
        b.fields();
}