public Parser generalRelationOp() {
        if (generalRelationOpParser == null) {
           FutureParser future = scoped("generalRelationOp");
           generalRelationOpParser = future;
           future.setParser(
               sequence(
                   optional(
                       choice(
                           token("IS"),
                           token("ARE")
                       )
                   ),
                   choice(
                       sequence(
                           optional(
                               negationOp()
                           ),
                           greaterOrEqualOp()
                       ),
                       sequence(
                           optional(
                               negationOp()
                           ),
                           lessOrEqualOp()
                       ),
                       sequence(
                           optional(
                               negationOp()
                           ),
                           greaterThanOp()
                       ),
                       sequence(
                           optional(
                               negationOp()
                           ),
                           lessThanOp()
                       ),
                       sequence(
                           optional(
                               negationOp()
                           ),
                           equalToOp()
                       ),
                       exceedsOp(),
                       equalsOp(),
                       unequalToOp()
                   )
               )
           );
        }

        return generalRelationOpParser;
    }