public Parser fileStatusClause() {
        if (fileStatusClauseParser == null) {
           FutureParser future = scoped("fileStatusClause");
           fileStatusClauseParser = future;
           future.setParser(
               sequence(
                   optional(
                       choice(
                           token("FILE"),
                           token("SORT")
                       )
                   ),
                   token("STATUS"),
                   optional(
                       token("IS")
                   ),
                   dataName(),
                   optional(
                       dataName()
                   )
               )
           );
        }

        return fileStatusClauseParser;
    }