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#include <iostream>
#include <type_traits>
using namespace std;
 
class A{};
class B:public A {};
 
template <bool Inherited>
class Checker;  // error, not implemented if not inherited
 
template<>
class Checker<true> { /* empty*/ };
 
 
template <typename T>
class Test
{
	 private:
		//Checker< std::is_base_of<A,T>::value > check;
		//   or use static_assert
		static_assert(std::is_base_of<A,T>::value,"Type T must inherit from A");
};
 
int main()
{
 
	Test<B> test1;
	Test<int> test2;
	return 0;
}

prog.cpp: In instantiation of 'class Test<int>':
prog.cpp:28:12:   required from here
prog.cpp:21:3: error: static assertion failed: Type T must inherit from A
   static_assert(std::is_base_of<A,T>::value,"Type T must inherit from A");
   ^

Standard output is empty