MODULE TSetConst;
// SET CONST declarations: a char-range literal, a literal with a char
// constant, and a union of two set constants, all folded to static
// masks.  Exit 42.
TYPE CharSet = SET OF CHAR;
     Colour = (Red, Green, Blue);
     CS = SET OF Colour;
CONST Digits = CharSet{"0".."9"};
      Signs  = CharSet{'+', '-'};
      NumCh  = Signs + Digits;          (* union of two set constants *)
      Warm   = CS{Red, Blue};
VAR c : CHAR;
    s : CharSet;
    col : CS;
    ExitCode : INTEGER;
BEGIN
  c := '5';
  s := Digits;
  col := Warm;
  IF (c IN s) AND ('+' IN NumCh) AND ('9' IN NumCh) AND NOT ('z' IN NumCh)
     AND (Red IN col) AND NOT (Green IN col)
  THEN ExitCode := 42 ELSE ExitCode := 1 END
END TSetConst.