void Relabelling(out PreProcessActions preproc)
 {
     preproc = null; string relabelTo, relabelFrom; RelabelActions labels = new RelabelActions();
     Expect(21);
     Token first = t;
     if (la.kind == 6) {
     Get();
     preproc = new CustomPreprocess(t.val.Replace(":","")); SetPos(preproc, first);
     } else if (la.kind == 3) {
     Get();
     relabelTo = t.val; SetPos(labels, first);
     Expect(22);
     Expect(3);
     relabelFrom = t.val; labels.Add(relabelFrom, relabelTo);
     while (la.kind == 11) {
         Get();
         Expect(3);
         relabelTo = t.val;
         Expect(22);
         Expect(3);
         relabelFrom = t.val; labels.Add(relabelFrom, relabelTo);
     }
     preproc = labels;
     } else SynErr(44);
     Expect(23);
 }
 public virtual void Visit(PreProcessActions actions)
 {
 }
 public virtual string Format(PreProcessActions labels)
 {
     if (labels.Count == 0) {
         return "";
     } else {
         StringList temp = new StringList();
         foreach (object id in labels) {
             temp.Add(id.ToString());
         }
         return "[" + Join(", ", temp) + "]";
     }
 }