fork download
copy 
  1. #include <iostream>
  2. #include <memory>
  3.  
  4. // Macros make the call much more readable: http://w...content-available-to-author-only...t.com/c++-faq-lite/pointers-to-members.html#faq-33.6
  5. #define CALL_MEMBER_FN(object, ptrToMember) ((object).*(ptrToMember))
  6. template <class T>
  7. struct Second
  8. {
  9.     // Typedefs make this much more readable: http://w...content-available-to-author-only...t.com/c++-faq-lite/pointers-to-members.html#faq-33.5
  10.     typedef void (T::*SecondTriggeredCallback)(void);
  11.  
  12.     // You'll also need an *instance* of the "T" class
  13.     Second(SecondTriggeredCallback SecondTriggered, T& t)
  14.     {
  15.         CALL_MEMBER_FN(t, SecondTriggered)();
  16.     }
  17. };
  18.  
  19. class First
  20. {
  21. public:
  22.     First()
  23.         :second(nullptr)
  24.     {
  25.         std::cout << "first class was created" << std::endl;
  26.         second.reset(new Second<First>(&First::SecondTriggered, *this));
  27.     }
  28.  
  29.     void SecondTriggered()
  30.     {
  31.         std::cout << "second class was created and responded" << std::endl;
  32.     }
  33.  
  34. private:
  35.     std::unique_ptr<Second<First>> second;
  36. };
  37.  
  38. int main()
  39. {
  40.     First first;
  41. }
  42.  
Success #stdin #stdout 0s 2984KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
first class was created
second class was created and responded
https://ideone.com/129OJo
language:
C++14 (gcc 8.3)
created:
10 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!