public Parser cancelStatement() {
        if (cancelStatementParser == null) {
           FutureParser future = scoped("cancelStatement");
           cancelStatementParser = future;
           future.setParser(
               sequence(
                   token("CANCEL"),
                   plus(
                       choice(
                           identifier(),
                           alphanumeric()
                       )
                   )
               )
           );
        }

        return cancelStatementParser;
    }