c++模版元编程

#include<iostream>

using namespace std;
template<int n>
class Factorial{
public:
enum{ value = n * Factorial<n-1>::value };
};
template<>
class Factorial<1>{
public:
enum{ value = 1 };
};

int main()
{
cout << Factorial<5>::value << endl;
system("pause");
return 0;
}

#include<iostream>

using namespace std;

template<int n, class Function>
class loop{
public:
static void Do(Function fun)
{
loop<n - 1, Function>::Do(fun);
fun(n);
}
};
template<class Function>
class loop<-1, Function>{
public:
static void Do(Function fun){}
};
void work(int i)
{
cout << "work " << i << endl;
}
int main()
{
loop<5, decltype(work)>::Do(work);
system("pause");
return 0;
}