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  1. template<typename T> struct S {};
  2. template<typename T> struct R {};
  3.  
  4. template<
  5.   typename T,
  6.   typename V>
  7. struct xxx;
  8.  
  9. template<
  10.  template <class> class A,
  11.  template <class> class B,
  12.  typename X,
  13.  typename Y>
  14. struct xxx<A<X>, B<Y>> {
  15.   static constexpr const int value = false;
  16. };
  17.  
  18.  
  19. template<
  20.  template <class> class U,
  21.  typename X,
  22.  typename Y>
  23. struct xxx<U<X>, U<Y>> {
  24.   static constexpr const int value = true;
  25. };
  26.  
  27. int main() {
  28.   typedef S<double> s1;
  29.   typedef S<int> s2;
  30.   typedef R<int> s3;
  31.   static_assert(xxx<s1, s2>::value,
  32.                 "No, assertion must not be raised");
  33.   static_assert(xxx<s2, s3>::value,
  34.                 "Yes, assertion must be raised");
  35. }
Compilation error #stdin compilation error #stdout 0s 0KB
comments (?)
stdin 
Standard input is empty
compilation info 
prog.cpp:33:3: error: static_assert failed "Yes, assertion must be raised"
  static_assert(xxx<s2, s3>::value,
  ^             ~~~~~~~~~~~~~~~~~~
1 error generated.
stdout 
Standard output is empty
https://ideone.com/3ShRwM
language:
C++14 (clang 8.0)
created:
6 years ago
visibility:
secret

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