#include <iostream>
#include <type_traits>

//#define DEFINE_F

#ifdef DEFINE_F
void f()
{

}
#endif

namespace
{
	constexpr struct special
    {
      std::false_type operator()() const;
    }f;	
}

struct checkForF
{
	static const constexpr auto value = std::conditional< std::is_same<std::false_type, decltype(::f())>::value, std::false_type, std::true_type >::type();
};

int main()
{
  	std::cout << checkForF::value << std::endl;
}