code: public boolean isSameAs(UnconditionalValueDerefSet otherFact) {
          return valueNumbersUnconditionallyDereferenced.equals(otherFact.valueNumbersUnconditionallyDereferenced)
                  && derefLocationSetMap.equals(otherFact.derefLocationSetMap);
      }
docs: Return whether or not this dataflow fact is identical to the one given.
  
  @param otherFact
  another dataflow fact
  @return true if the other dataflow fact is identical to this one, false
  otherwise