factorial in meta-programming

metafact.cpp

#include <iostream>

template <int i>
struct factorial {
  enum {
    result = factorial<i-1>::result * i,
  };
};

template <>
struct factorial<1> {
  enum {
    result = 1,
  };
};

template <>
struct factorial<0> {
  enum {
    result = 1,
  };
};

int main() {
  std::cout << factorial<5>::result << std::endl;
}