@NotNull
  Equation mkEquation(PResult result) {
    if (NPE == result) {
      return new Equation(aKey, Value.Top);
    }
    if (Identity == result || Return == result) {
      return new Equation(aKey, Value.Null);
    }
    else {
      ConditionalNPE condNpe = (ConditionalNPE) result;
      Set<Component> components = condNpe.sop.stream().map(prod -> new Component(Value.Top, prod)).collect(Collectors.toSet());
      return new Equation(aKey, new Pending(components));
    }
  }
@NotNull
  Equation mkEquation(PResult result)