public Parser raiseStatement() {
        if (raiseStatementParser == null) {
           FutureParser future = scoped("raiseStatement");
           raiseStatementParser = future;
           future.setParser(
               sequence(
                   token("RAISE"),
                   optional(
                       identifier()
                   )
               )
           );
        }

        return raiseStatementParser;
    }