pure interface of class Shuffle

public abstract class Shuffle
  extends Printable
{
    public Obj source;
    public Obj target;
    public abstract int shuffle(int i);
    public static Shuffle identity(Obj X);
    public static Shuffle zero(Obj X,
                               Obj Y);
    public static Shuffle terminal(Obj X);
    public static Shuffle initial(Obj X);
    public Shuffle comediate(Shuffle f);
    public Shuffle mediate(Shuffle f);
    public Shuffle comp(Shuffle f);
    public Shuffle tensor(Shuffle f);
    public Mor morphism();
    public void print(Printer p);
    public Shuffle();
}