(*
 * Compute nth fibonacci number
 *
 * Examples:
 *
 *	6 : Fib -> 8
 *	7 : Fib -> 13
 *	8 : Fib -> 21
 *)

DEF Fib AS 
   IF [id,#2] | < THEN id
   ELSE
      sub1 | [Fib,sub1|Fib] | +
   END;
