invoke_tuple.cpp

template<typename Op, typename Tuple, std::size_t... Is>
void invoke(Op op, const Tuple& args, std::index_sequence<Is...>)
{
    op(std::get<Is>(args)...);
}

template<typename Op, typename... Args>
void invoke(Op op, const std::tuple<Args...>& args)
{
    invoke(op, args, std::index_sequence_for<Args...>{});
}

int main()
{
    invoke(std::printf, std::make_tuple("%d, %f", 3, 6.1));
}