143 template <class... Args, class... Labels>
144 struct LabeledTuple<std::tuple<Args...>, Labels...>
146     static_assert(sizeof...(Args) == sizeof...(Labels));
148     using tuple_type = std::tuple<Args...>;
155     LabeledTuple(Args... args) : value(std::move(args)...) {}  in LabeledTuple()
163         to_json_all(j, std::make_index_sequence<sizeof...(Args)>());  in to_json()
174         from_json_all(j, std::make_index_sequence<sizeof...(Args)>());  in from_json()
280             static_assert(Idx + 1 < sizeof...(Args),  in find_item()
289 template <class... Args, class... Labels>
291                     const LabeledTuple<std::tuple<Args...>, Labels...>& tuple)  in to_json()  argument
296 template <class... Args, class... Labels>
298                       LabeledTuple<std::tuple<Args...>, Labels...>& tuple)  in from_json()  argument