public Parser unstringStatement() {
        if (unstringStatementParser == null) {
           FutureParser future = scoped("unstringStatement");
           unstringStatementParser = future;
           future.setParser(
               sequence(
                   token("UNSTRING"),
                   identifier(),
                   optional(
                       sequence(
                           token("DELIMITED"),
                           optional(
                               token("BY")
                           ),
                           optional(
                               token("ALL")
                           ),
                           choice(
                               identifier(),
                               literal()
                           ),
                           star(
                               sequence(
                                   token("OR"),
                                   optional(
                                       token("ALL")
                                   ),
                                   choice(
                                       identifier(),
                                       literal()
                                   )
                               )
                           )
                       )
                   ),
                   token("INTO"),
                   plus(
                       sequence(
                           identifier(),
                           optional(
                               sequence(
                                   token("DELIMITER"),
                                   optional(
                                       token("IN")
                                   ),
                                   identifier()
                               )
                           ),
                           optional(
                               sequence(
                                   token("COUNT"),
                                   optional(
                                       token("IN")
                                   ),
                                   identifier()
                               )
                           )
                       )
                   ),
                   optional(
                       sequence(
                           optional(
                               token("WITH")
                           ),
                           token("POINTER"),
                           identifier()
                       )
                   ),
                   optional(
                       sequence(
                           token("TALLYING"),
                           optional(
                               token("IN")
                           ),
                           identifier()
                       )
                   ),
                   optional(
                       sequence(
                           optional(
                               token("ON")
                           ),
                           token("OVERFLOW"),
                           nestedStatements()
                       )
                   ),
                   optional(
                       sequence(
                           token("NOT"),
                           optional(
                               token("ON")
                           ),
                           token("OVERFLOW"),
                           nestedStatements()
                       )
                   ),
                   optional(
                       token("END-UNSTRING")
                   )
               )
           );
        }

        return unstringStatementParser;
    }