Function find_inner_last

include/jsoncons_ext/jsonpointer/jsonpointer.hpp:1366–1374

    template <typename Iterator,typename StringT>
    Iterator find_inner_last(Iterator first, Iterator last, std::size_t offset, const StringT& token)
    {
        Iterator it = first;
        while (it != last && *(it->first.tokens().begin() + offset) == token)
        {
            ++it;
        }
        return it;
    }

    template <typename Json, typename Iterator>
    jsoncons::optional<Json> try_unflatten_array(Iterator first, Iterator last, std::size_t offset);