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  1. #include <iostream>
  2. #include <typeinfo>
  3.  
  4. struct A { virtual void Foo() {} };
  5. struct B : public A { void Foo() {} };
  6. struct C : public A { };
  7.  
  8. int main() {
  9. 	std::cout << "naive - fails" << std::endl;
  10. 	std::cout << int(&A::Foo == &A::Foo) << std::endl;
  11. 	std::cout << int(&A::Foo == &B::Foo) << std::endl;
  12. 	std::cout << int(&A::Foo == &C::Foo) << std::endl;
  13.  
  14. 	std::cout << "needs gcc-only PMF extension - semi-works" << std::endl;
  15. 	std::cout << int(reinterpret_cast<void(*)()>(&A::Foo) == reinterpret_cast<void(*)()>(&A::Foo)) << std::endl;
  16. 	std::cout << int(reinterpret_cast<void(*)()>(&A::Foo) == reinterpret_cast<void(*)()>(&B::Foo)) << std::endl;
  17. 	std::cout << int(reinterpret_cast<void(*)()>(&A::Foo) == reinterpret_cast<void(*)()>(&C::Foo)) << std::endl;
  18.  
  19. 	std::cout << "proper solution - works" << std::endl;
  20. 	std::cout << int(typeid(&A::Foo) == typeid(&A::Foo)) << std::endl;
  21. 	std::cout << int(typeid(&A::Foo) == typeid(&B::Foo)) << std::endl;
  22. 	std::cout << int(typeid(&A::Foo) == typeid(&C::Foo)) << std::endl;
  23. 	return 0;
  24. }
Success #stdin #stdout 0s 3340KB
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stdin
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Standard input is empty
stdout
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naive - fails
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needs gcc-only PMF extension - semi-works
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proper solution - works
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https://ideone.com/xcQOT6
language:
C++14 (gcc 8.3)
created:
10 years ago
visibility:
public

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