*  rec2a.ref

*$STRATEGY Applicative;

RecNumber {
   e.1 = <Rec (e.1) e.1>;
 }

Rec {
  ( )  = ;
  ((e.1) e.2) e.3 = <Rec (e.2) <Rec1 (e.1) e.3> >;
 }

Rec1 {
  ( ) = ;
  ('1' e.1) ( ) e.3 = <Rec1 (e.1) e.3>;
  (e.1) ('1' e.2) e.3 = (e.2) <Rec1 (e.1) e.3>;
 }