fork download
copy 
  1. #include <tuple>
  2. #include <iostream>
  3. #include <string>
  4.  
  5. // tuple printer
  6. template<class Tuple, std::size_t N>
  7. struct TuplePrinter {
  8.     static std::ostream& print(std::ostream& os, const Tuple& t)
  9.     {
  10.         TuplePrinter<Tuple, N - 1>::print(os, t);
  11.         os << ", " << std::get<N - 1>(t);
  12.         return os;
  13.     }
  14. };
  15.  
  16. template<class Tuple>
  17. struct TuplePrinter<Tuple, 1> {
  18.     static std::ostream& print(std::ostream& os, const Tuple& t)
  19.     {
  20.         os << std::get<0>(t);
  21.         return os;
  22.     }
  23. };
  24.  
  25. template<class... Args>
  26. std::ostream& print(std::ostream& os, const std::tuple<Args...>& t)
  27. {
  28.     os << "(";
  29.     TuplePrinter<decltype(t), sizeof...(Args)>::print(os, t);
  30.     os << ")\n";
  31.     return os;
  32. }
  33.  
  34.  
  35. // class to keep tuple inside
  36. template<typename... Args>
  37. class tuple_class {
  38.     template<typename... Args2>
  39.     friend std::ostream& operator<<(std::ostream& os, const tuple_class<Args2...> &m);
  40.  
  41.     std::tuple<Args...> tup;
  42. public:
  43.     tuple_class(Args&&... args) : tup(std::forward<Args>(args)...) {
  44.  
  45.     }
  46. };
  47.  
  48. // usage of the printer
  49. template<typename... Args>
  50. std::ostream& operator<<(std::ostream& os, const tuple_class<Args...> &m) {
  51.     print(os, m.tup);
  52.     return os;
  53. }
  54.  
  55.  
  56.  
  57. int main() {
  58.     tuple_class<int,float,std::string> tc( 1,3.0f,"string" );
  59.     std::cout << tc;
  60.     return 0;
  61. }
Success #stdin #stdout 0s 3412KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
(1, 3, string)
https://ideone.com/2UwhxC
language:
C++14 (gcc 8.3)
created:
9 years ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!