tables::row::col
template <typename... Ts, is_primitive_type... Ps>
template<typename T>
requires in<T,std::tuple<Ts...>>
auto
row<std::pair<Ts,Ps>...>::col() const
Returns value at given volumn
template <typename... Ts, is_primitive_type... Ps>
template<typename T>
requires in<T,std::tuple<Ts...>>
auto
row<std::pair<Ts,Ps>...>::col() const
Returns value at given volumn