Function equalTo

lib/vfvalue.h:172–176

        template<class T, REQUIRES("T must be an arithmetic type", std::is_arithmetic<T> )>
        bool equalTo(const T& x) const {
            bool result = false;
            visitValue(*this, std::bind(equalVisitor{}, std::ref(result), x, std::placeholders::_1));
            return result;
        }

        void decreaseRange() {
            if (bound == Bound::Lower)