http://cpplover.blogspot.com/2010/12/c0x.html

himatubusi.cpp

// 今手元に variadic templates をサポートした gcc がない（なんなら gcc 自体ない）からコンパイルが試せていない
// f 0 0 = [0]
// f n 0 = []
// f n m = n : f n m - 1
// g n = f n n
// h n = foldl (++) [] $ map g (0 .. n)

template <int... seq>
struct ilist;

template <int n, typename List>
struct cons;

template <int n, int... seq>
struct cons<n, ilist<seq...>> {
  typedef ilist<n, seq...> type;
};

template <int n, int m>
struct f {
  static const int head = n;
  typedef typename f<n, m-1>::type = tail;
  typedef typename cons<head, tail>::type = type;
};

template <int n>
struct f<n, 0> {
  typedef ilist<> type;
};

template <>
struct f<0, 0> {
  typedef ilist<0> type;
};

template <int n>
struct g {
  typedef typename f<n, n>::type type;
};

template <template <int> class unary_op, typename List>
struct map;

template <template <int> class unary_op, int... seq>
struct map<unary_op, ilist<seq...>> {
  typedef ilist<typename unary_op<seq>::type...> type;
};

template <typename Lhs, typename Rhs>
struct append;

template <int... lhs, int... rhs>
struct append<ilist<lhs...>, ilist<rhs...>> {
  typedef ilist<lhs..., rhs...> type;
};

template <int n>
struct range {
  typedef typename range<n-1>::type tmp;
  typedef typename append<tmp, ilist<n>>::type type;
};

template <>
struct range<0> {
  typedef ilist<0> type;
};

template <template <typename, typename> class bin_op, int init, typename List>
struct foldl;

template <template <int, int> class bin_op, int init, int head, int... tail>
struct foldl<bin_op, init, ilist<head, tail...>> {
  typedef typename bin_op<init, head>::type tmp;
  typedef typename foldl<bin_op, tmp, ilist<tail...>>::type type;
};

template <template <int, int> class bin_op, int init>
struct foldl<bin_op, init, ilist<>> {
  typedef init type;
};

template <int n>
struct h {
  typedef typename range<n>::type tmp1;
  typedef typename map<g, tmp1>::type tmp2;
  typedef typename foldl<append, ilist<>, tmp2>::type type;
};

template <typename List>
struct ilist_to_array;

template <int... seq>
struct ilist_to_array<ilist<seq...>> {
  static const int array[] = { seq... };
};