MODULE TExceptCase;
(* M4: a CASE selector with no matching label and no ELSE raises
   caseSelectException. *)
FROM M2EXCEPTION IMPORT
  M2Exception, IsM2Exception, caseSelectException;

TYPE
  Colour = (red, green, blue);
VAR ExitCode : INTEGER;
VAR c : Colour;

PROCEDURE Select;
BEGIN
  c := blue;
  CASE c OF
    red:   ExitCode := 1
  | green: ExitCode := 2
  END;
  ExitCode := 3
EXCEPT
  IF IsM2Exception() AND (M2Exception() = caseSelectException) THEN
    ExitCode := 42
  ELSE
    ExitCode := 4
  END
END Select;

BEGIN
  ExitCode := 0;
  Select
END TExceptCase.