Function less_quad

tests-cpp/small/test_sort_family.cpp:45–49

    }

    auto less_quad() {
        return [](const void * a, const void * b) {
            return static_cast<const Quad*>(a)->key < static_cast<const Quad*>(b)->key;
        };
    }

    template <typename T>
    bool is_sorted_range(const T * data, size_t n) {