Method get_string

3rd/json/include/nlohmann/json.hpp:5398–5413

    */
    template<typename NumberType>
    bool get_string(const input_format_t format,
                    const NumberType len,
                    string_t& result)
    {
        bool success = true;
        std::generate_n(std::back_inserter(result), len, [this, &success, &format]()
        {
            get();
            if (JSON_UNLIKELY(not unexpect_eof(format, "string")))
            {
                success = false;
            }
            return static_cast<char>(current);
        });
        return success;
    }

    /*!
    @param[in] format   the current format (for diagnostics)