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  1. #include <iostream>
  2. #include <typeinfo>
  3.  
  4. class B;
  5.  
  6. struct A {
  7. 	decltype(auto) func(B*);
  8. 	decltype(auto) func(B&);
  9. };
  10.  
  11. template<typename T>
  12. void size() {
  13. 	std::cout << "Size of " << typeid(T).name() << ": " << sizeof(T) << '\n';
  14. }
  15.  
  16. template<>
  17. void size<B*>() {
  18. 	std::cout << "Size of B*: " << sizeof(B*) << '\n';
  19. }
  20.  
  21. // Error if uncommented.
  22. //template<>
  23. //void size<B>() {
  24. //	std::cout << "Size of B: " << sizeof(B) << '\n';
  25. //}
  26.  
  27. class B {
  28. 	friend class A;
  29.  
  30. 	void func() const { std::cout << "Be funky.\n"; }
  31. };
  32.  
  33. decltype(auto) A::func(B* b) { return b->func(); }
  34. decltype(auto) A::func(B& b) { return b.func(); }
  35.  
  36. int main() {
  37. 	A a;
  38. 	B b;
  39.  
  40. 	a.func(b);
  41. 	a.func(&b);
  42.  
  43. 	size<B*>();
  44. 	size<B>();
  45. }
Success #stdin #stdout 0s 3468KB
comments (?)
stdin
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Standard input is empty
stdout
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Be funky.
Be funky.
Size of B*: 4
Size of 1B: 1
https://ideone.com/2O5qfU
language:
C++14 (gcc 8.3)
created:
9 years ago
visibility:
secret

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