Picking Out Elements Using a Logical List

[Didier Lachieze]

Nice idea to use the recursion to solve this problem. Here is a variation of your first program:

Code:

EXPORT BOOLLIST5(LA,LB)
BEGIN
  LOCAL LC:={};
  IF LB(1) THEN LC(1):=LA(1); END;
  IF SIZE(LA)==1 THEN RETURN LC; END;
  LB(0):=LB(1);
  CONCAT(LC,BOOLLIST5(tail(LA),tail(LB)));
END;