4.3BSD - /usr/src/ucb/dbx/tests/pc/sets.p

   1: program sets (input, output);
   2: type
   3:     Color = (RED, BLUE, GREEN);
   4:     ColorSet = set of Color;
   5: var
   6:     s : ColorSet;
   7: 
   8: procedure p (var s : ColorSet);
   9: begin
  10:     s := [RED, BLUE];
  11: end;
  12: 
  13: begin
  14:     p(s);
  15:     if BLUE in s then begin
  16:     s := s - [BLUE];
  17:     end;
  18: end.