public static Keyword tryScanForValueClashProof(ControlFrame frame) {
    { Object old$ReversepolarityP$000 = Logic.$REVERSEPOLARITYp$.get();
      Object old$DontusedefaultknowledgeP$000 = Logic.$DONTUSEDEFAULTKNOWLEDGEp$.get();

      try {
        Native.setBooleanSpecial(Logic.$REVERSEPOLARITYp$, false);
        Native.setBooleanSpecial(Logic.$DONTUSEDEFAULTKNOWLEDGEp$, ((Boolean)(Logic.$DONTUSEDEFAULTKNOWLEDGEp$.get())).booleanValue());
        { Proposition proposition = frame.proposition;
          Iterator clashiterator = Proposition.allClashingPropositions(proposition);
          TruthValue truthvalue = (clashiterator.nextP() ? Logic.propositionsIteratorTruthValue(clashiterator) : ((TruthValue)(null)));

          if ((truthvalue == Logic.DEFAULT_TRUE_TRUTH_VALUE) ||
              (truthvalue == Logic.DEFAULT_FALSE_TRUTH_VALUE)) {
            Native.setBooleanSpecial(Logic.$DONTUSEDEFAULTKNOWLEDGEp$, true);
            clashiterator = Proposition.allClashingPropositions(proposition);
            if (clashiterator.nextP()) {
              truthvalue = Logic.propositionsIteratorTruthValue(clashiterator);
            }
          }
          frame.truthValue = TruthValue.invertTruthValue(truthvalue);
          return (((truthvalue != null) ? Logic.KWD_FINAL_SUCCESS : Logic.KWD_FAILURE));
        }

      } finally {
        Logic.$DONTUSEDEFAULTKNOWLEDGEp$.set(old$DontusedefaultknowledgeP$000);
        Logic.$REVERSEPOLARITYp$.set(old$ReversepolarityP$000);
      }
    }
  }