很怪异的c++模板

#include <cstdlib>#include <iostream>using namespace std;template < class T>struct is_Int{static const bool value = false;};template<>struct is_Int<int>{static const bool value = true;};template<class T>void Is_int(T param){     if(is_Int<T>::value){                               }}int main(int argc, char *argv[]){    system("PAUSE");    return EXIT_SUCCESS;}