Function unflatten_object

include/jsoncons_ext/jsonpointer/jsonpointer.hpp:1380–1433

    template <typename Json, typename Iterator>
    Json unflatten_object(Iterator first, Iterator last, std::size_t offset, unflatten_options options)
    {
        Json jo{json_object_arg};

        std::size_t length = std::distance(first, last);

        auto it = first;
        while (it != last)
        {
            if (it->first.tokens().size() == offset && length == 1)
            {
                return *(it->second);
            }
            if (it->first.tokens().size() == offset)
            {
                ++it;
            }
            else if (it->first.tokens().size() < offset)
            {
                return jsoncons::optional<Json>{};
            }
            else
            {
                auto jt = it->first.tokens().begin() + offset;
                if (offset + 1 == it->first.tokens().size())
                {
                    jo.try_emplace(*jt, *(it->second));
                    ++it;
                }
                else 
                {
                    auto inner_last = find_inner_last(it, last, offset, *jt);
                    if (options == unflatten_options{})
                    {
                        auto res = try_unflatten_array<Json,Iterator>(it, inner_last, offset+1);
                        if (!res)
                        {
                            jo.try_emplace(*jt, unflatten_object<Json,Iterator>(it, inner_last, offset+1, options));
                        }
                        else
                        {
                            jo.try_emplace(*jt, std::move(*res));
                        }
                    }
                    else
                    {
                        jo.try_emplace(*jt, unflatten_object<Json,Iterator>(it, inner_last, offset+1, options));
                    }
                    it = inner_last;
                }
            }
        }
        return jsoncons::optional<Json>{std::move(jo)};
    }

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