RETURN

  Returns to the procedure that called the current procedure.  (The return
  is to the statement following the one that called the current procedure.)
  RETURN is can be used in the ON_ERROR section of a procedure or to return
  a value or status in a procedure.

  Syntax:

     RETURN [value]

  Parameters

     value      Optionally, a value to be returned to the calling procedure,
                such as a variable or a status value (1 for true; 0 for
                false).

  Examples

  1.  In the following procedure, RETURN is used in the ON_ERROR section of
      a procedure (in this case, to attach to the parent process):

      PROCEDURE user_attach_to_parent
         ON_ERROR
            IF ERROR = TPU$_NOPARENT
               THEN
                  MESSAGE ("Not running DECTPU in a subprocess.");
                  RETURN;
            ENDIF;
         ENDON_ERROR;
         ATTACH;
      ENDPROCEDURE;

  2.  In the following procedure, RETURN passes a value to the calling
      procedure (in this case, a keyword for a key pressed after the shift
      or GOLD key):

      PROCEDURE user_get_gold_key
         LOCAL gold_key;         ! keyword for key pressed after GOLD
         SET (SHIFT_KEY, LAST_KEY);
         gold_key := KEY_NAME (READ_KEY, SHIFT_KEY);
         RETURN (key_to_shift);
      ENDPROCEDURE;

  3.  In the following procedure, RETURN passes a value (true or false) for
      the status of a procedure (in this case, whether the user is at the
      end of a line):

      PROCEDURE user_at_eol
         ON_ERROR
            RETURN (1);      ! Suppress warning message
         ENDON_ERROR;
         IF CURRENT_OFFSET = LENGTH (CURRENT_LINE)
            THEN
               RETURN (1);   ! True -- at end of line
            ELSE
               RETURN (0);   ! False -- not at end of line
         ENDIF;
      ENDPROCEDURE;