#pragma once

namespace ft {
// is_integral:
template < class T, T val > struct integral_constant {
  typedef integral_constant< T, val > type;
  typedef T                           value_type;
  static const T                      value = val;
                                      operator T() const;
};

typedef integral_constant< bool, true >  true_type;
typedef integral_constant< bool, false > false_type;

template < class T > struct is_integral : public false_type {};
template < class T > struct is_integral< const T > : public false_type {};

template <> struct is_integral< bool > : public true_type {};
template <> struct is_integral< double > : public true_type {};

template <> struct is_integral< char > : public true_type {};
template <> struct is_integral< short > : public true_type {};
template <> struct is_integral< int > : public true_type {};
template <> struct is_integral< long > : public true_type {};
template <> struct is_integral< long long > : public true_type {};

template <> struct is_integral< unsigned char > : public true_type {};
template <> struct is_integral< unsigned short > : public true_type {};
template <> struct is_integral< unsigned int > : public true_type {};
template <> struct is_integral< unsigned long > : public true_type {};
template <> struct is_integral< unsigned long long > : public true_type {};

// enable_if:
template < bool B, class T = void > struct enable_if {};

template < class T > struct enable_if< true, T > {
  typedef T type;
};

} // namespace ft