关于遍历std::tuple中的元素

[悠然的二货]

#include <iostream>
#include <tuple>
#include <string>
 
using namespace std;
 
template<typename Tuple, int N = std::tuple_size<Tuple>::value>
struct Printer
{
  static void log(Tuple& t) {
    Printer<Tuple, N - 1>::log(t);
 
    using type = typename std::tuple_element<N - 1, Tuple>::type;
    std::string ts = typeid(type).name();
    type& v = std::get<N - 1>(t);
 
    std::cout << ts << ":" << v << std::endl;
  }
};
 
template<typename Tuple>
struct Printer<Tuple,  1>
{
  static void log(Tuple& t) {
    using type = typename std::tuple_element<0, Tuple>::type;
    std::string ts = typeid(type).name();
    type& v = std::get<0>(t);
 
    std::cout << ts << ":" << v << std::endl;
  }
};
 
int main() {
  std::tuple<int, bool, string> t = std::forward_as_tuple(11, true, "ok");
  Printer<std::tuple<int, bool, string>>::log(t);
 
  return 1;
}

这个特例化模板是怎么做到遍历std::tuple的？不太理解