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  1. #include <iostream>
  2.  
  3. struct A {};
  4.  
  5. struct B {
  6.     static int bar() { std::cout << "B::bar()" << std::endl; return 0; }
  7. };
  8.  
  9. struct C {
  10.     void bar(int) { std::cout << "C::bar(int)" << std::endl; }
  11. };
  12.  
  13. template <typename T>
  14. class X {
  15. public:
  16.     static void foo() {
  17.         foo_impl(static_cast<T*>(nullptr));
  18.     }
  19. private:
  20.     template <typename U>
  21.     static auto foo_impl(U*) -> decltype(U::bar(), void()) {
  22.         U::bar();
  23.     }
  24.     static void foo_impl(...) {}
  25. };
  26.  
  27. int main() {
  28.     X<A>::foo();
  29.     X<B>::foo();
  30.     X<C>::foo();
  31. }
  32.  
Success #stdin #stdout 0s 2896KB
comments ()
stdin 
Standard input is empty
stdout 
B::bar()
https://ideone.com/UKVmIB
language:
C++14 (gcc 8.3)
created:
12 years ago
visibility:
public

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