pure interface of class PremonTypeFun

public class PremonTypeFun
  extends PremonType
{
    public PremonCat cat;
    public PremonType source;
    public PremonType target;
    public PremonTypeFun(PremonCat cat,
                         PremonType source,
                         PremonType target);
    public void print(Printer p);
    public Obj semantics();
    public boolean equals(PremonType V);
    public boolean traceable();
}