#include <iostream>
#include <type_traits>
using namespace std;

struct A { };
struct B { B& operator= (const B&) = delete; };

int main() {
	std::cout << std::boolalpha;
	std::cout << "is_copy_assignable:" << std::endl;
	std::cout << "int: " << std::is_copy_assignable<int>::value << std::endl;
	std::cout << "A: " << std::is_copy_assignable<A>::value << std::endl;
	std::cout << "B: " << std::is_copy_assignable<B>::value << std::endl;
	return 0;
}