@Override
 public RRaw materialize() {
   trace.materialize();
   return orig.materialize();
 }
 @Override
 public RComplex materialize() {
   trace.materialize();
   return orig.materialize();
 }
 @Override
 public RLogical materialize() {
   trace.materialize();
   return orig.materialize();
 }
 @Override
 public RString materialize() {
   trace.materialize();
   return orig.materialize();
 }