private ResultList evaluateListsFalse(AttributeNode.VariableValueList lhs, AttributeNode.VariableValueList rhs) {
        ResultList lst = evaluateListsTrue(lhs, rhs);
        if (lst.toResult() == Result.TRUE) {
            return new ResultList(Result.FALSE);
        } else if (lst.toResult() == Result.FALSE) {
            return new ResultList(Result.TRUE);
        } else {
            return lst;
        }
    }
Evaluates a binary comparison where one or both operands are null.
Boolean outcomes are only defined for (in)equality relations, all others
return Result.INVALID.

Precondition: lhs AND/OR rhs is null.
document/src/main/java/com/yahoo/document/select/rule/ComparisonNode.java