N>template<typename... args>
N>class tail_consumer {};

N>template<typename... args>
N>class full_consumer 
N>{
N>  using tail = tail_consumer<???>;
N>};

N>full_consumer<int, char, long>::tail <- ожидается что tail будет : <char, long>
N>

template<typename... args>
class tail_consumer {};

template<typename... args>
class full_consumer;
    
template<typename Arg, typename... Args>
class full_consumer<Arg, Args...>
{
  using tail = tail_consumer<Args...>;
};
template <>
class full_consumer<>
{ };