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  1. #include <iostream>
  2. #include <type_traits>
  3.  
  4. template <typename T>
  5. struct A {
  6.     int val = 0;
  7.  
  8.     template<size_t N,
  9.              typename U = T,
  10.              typename = std::enable_if_t<sizeof(U)>
  11.             >
  12.     A(int (&ar)[N]) {};
  13.  
  14.     A(){}
  15. };
  16.  
  17. struct YES {};
  18. struct NO;
  19.  
  20. int main() {
  21. 	int a[10];
  22.     A<YES> y(a);
  23.     A<NO> n;
  24.     std::cout << "YES: " << y.val << std::endl
  25.               << "NO:  " << n.val << std::endl;
  26. }
Success #stdin #stdout 0s 5220KB
comments (?)
stdin
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Standard input is empty
stdout
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YES: 0
NO:  0
https://ideone.com/6OoiQD
language:
C++14 (gcc 8.3)
created:
3 days ago
visibility:
public

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