#include <iostream>

#include <type_traits>

#include <string>

#include <stdexcept>

int main()

{

std::cout << std::boolalpha

<< "std::string has a virtual destructor? "

<< std::has_virtual_destructor<std::string>::value << '\n'

<< "std::runtime_error has a virtual destructor? "

<< std::has_virtual_destructor<std::runtime_error>::value << '\n';

}