IMPLEMENTATION MODULE EXCEPTIONS;
(* ISO EXCEPTIONS implemented over the V3 runtime binding.  The opaque
   ExceptionSource is an identity token; it is never dereferenced. *)

FROM SYSTEM IMPORT ADDRESS;
IMPORT SysExceptions;
IMPORT M2EXCEPTION;

TYPE
  ExceptionSource = ADDRESS;

PROCEDURE AllocateSource (VAR newSource : ExceptionSource);
BEGIN
  newSource := SysExceptions.NewSource()
END AllocateSource;

PROCEDURE RAISE (source : ExceptionSource; number : ExceptionNumber;
                 message : ARRAY OF CHAR);
BEGIN
  SysExceptions.RaiseUser(source, number, message)
END RAISE;

PROCEDURE CurrentNumber (source : ExceptionSource) : ExceptionNumber;
BEGIN
  IF SysExceptions.IsSource(source) THEN
    RETURN SysExceptions.Number()
  ELSE
    SysExceptions.RaiseLang(ORD(M2EXCEPTION.exException));
    RETURN 0
  END
END CurrentNumber;

PROCEDURE GetMessage (VAR text : ARRAY OF CHAR);
BEGIN
  SysExceptions.CopyMessage(text)
END GetMessage;

PROCEDURE IsCurrentSource (source : ExceptionSource) : BOOLEAN;
BEGIN
  RETURN SysExceptions.IsSource(source)
END IsCurrentSource;

PROCEDURE IsExceptionalExecution () : BOOLEAN;
BEGIN
  RETURN SysExceptions.Active()
END IsExceptionalExecution;

END EXCEPTIONS.