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  1. #include <iostream>
  2. #include <typeinfo>
  3.  
  4. struct X { };
  5.  
  6. template<typename T> 
  7. struct aux
  8. {
  9.   void operator()(T&&) const { std::cout << 1 << std::endl; }  
  10. };
  11.  
  12. template<typename T> 
  13. struct aux<T&>
  14. {
  15.   void operator()(T&) const { std::cout << 2 << std::endl; }  
  16. };
  17.  
  18. template<typename T> void g(T&& t)
  19. { 
  20.     aux<T>()(std::forward<T>(t)); 
  21. }
  22.  
  23. int main()
  24. {
  25.     X x;
  26.     g(x);   // 2
  27.     g(X()); // 1
  28. }
Success #stdin #stdout 0s 3296KB
comments (?)
stdin 
Standard input is empty
stdout 
2
1
https://ideone.com/QnM8e0
language:
C++14 (gcc 8.3)
created:
10 years ago
visibility:
public

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