docs: @Override
      public void meetInto(TypeQualifierValueSet fact, Edge edge, TypeQualifierValueSet result) throws DataflowAnalysisException {
          if (fact.isTop() || result.isBottom()) {
              // result does not change
              return;
          } else if (fact.isBottom() || result.isTop()) {
              result.makeSameAs(fact);
              return;
          }
  
          assert fact.isValid();
          assert result.isValid();
  
          result.mergeWith(fact);
      }