integer/include/boost/integer_traits.hpp

/* boost integer_traits.hpp header file
 *
 * Copyright Jens Maurer 2000
 * Permission to use, copy, modify, sell, and distribute this software
 * is hereby granted without free provided that the above copyright notice
 * appears in all copies and that both that copyright notice and this
 * permission notice appear in supporting documentation,
 *
 * Jens Maurer makes no representations about the suitability of this
 * software for any purpose. It is provided "as is" without express or
 * implied warranty.
 *
 * $Id$
 *
 * Idea by Beman Dawes, Ed Brey, Steve Cleary, and Nathan Myers
 */

#ifndef BOOST_INTEGER_TRAITS_HPP
#define BOOST_INTEGER_TRAITS_HPP

#include <limits>
#include <boost/config.hpp>

// This is an implementation detail and not part of the interface
#include <limits.h>


namespace boost {
template<class T>
class integer_traits : public std::numeric_limits<T>
{
public:
#ifndef BOOST_NO_INCLASS_MEMBER_INITIALIZATION
  static const bool is_integral = false;
#else
  enum { is_integral = false };
#endif
};

namespace detail {
template<class T, T min_val, T max_val>
class integer_traits_base
{
public:
#ifndef BOOST_NO_INCLASS_MEMBER_INITIALIZATION
  static const bool is_integral = true;
  static const T const_min = min_val;
  static const T const_max = max_val;
#else
  enum {
    is_integral = true,
    const_min = min_val,
    const_max = max_val
  };
#endif
};
} // namespace detail

template<>
class integer_traits<bool>
  : public std::numeric_limits<bool>,
    public detail::integer_traits_base<bool, false, true>
{ };

template<>
class integer_traits<char>
  : public std::numeric_limits<char>,
    public detail::integer_traits_base<char, CHAR_MIN, CHAR_MAX>
{ };

template<>
class integer_traits<signed char>
  : public std::numeric_limits<signed char>,
    public detail::integer_traits_base<signed char, SCHAR_MIN, SCHAR_MAX>
{ };

template<>
class integer_traits<unsigned char>
  : public std::numeric_limits<unsigned char>,
    public detail::integer_traits_base<unsigned char, 0, UCHAR_MAX>
{ };

// What about wchar_t ?

template<>
class integer_traits<short>
  : public std::numeric_limits<short>,
    public detail::integer_traits_base<short, SHRT_MIN, SHRT_MAX>
{ };

template<>
class integer_traits<unsigned short>
  : public std::numeric_limits<unsigned short>,
    public detail::integer_traits_base<unsigned short, 0, USHRT_MAX>
{ };

template<>
class integer_traits<int>
  : public std::numeric_limits<int>,
    public detail::integer_traits_base<int, INT_MIN, INT_MAX>
{ };

template<>
class integer_traits<unsigned int>
  : public std::numeric_limits<unsigned int>,
    public detail::integer_traits_base<unsigned int, 0, UINT_MAX>
{ };

template<>
class integer_traits<long>
  : public std::numeric_limits<long>,
    public detail::integer_traits_base<long, LONG_MIN, LONG_MAX>
{ };

template<>
class integer_traits<unsigned long>
  : public std::numeric_limits<unsigned long>,
    public detail::integer_traits_base<unsigned long, 0, ULONG_MAX>
{ };

#ifdef ULLONG_MAX
template<>
class integer_traits<long long>
  : public std::numeric_limits<long long>,
    public detail::integer_traits_base<long long, LLONG_MIN, LLONG_MAX>
{ };
template<>
class integer_traits<unsigned long long>
  : public std::numeric_limits<unsigned long long>,
    public detail::integer_traits_base<unsigned long long, 0, ULLONG_MAX>
{ };
#elif defined(ULONG_LONG_MAX)
template<>
class integer_traits<long long>
  : public std::numeric_limits<long long>,
    public detail::integer_traits_base<long long, LONG_LONG_MIN, LONG_LONG_MAX>
{ };
template<>
class integer_traits<unsigned long long>
  : public std::numeric_limits<unsigned long long>,
    public detail::integer_traits_base<unsigned long long, 0, ULONG_LONG_MAX>
{ };
#endif

} // namespace boost

#endif /* BOOST_INTEGER_TRAITS_HPP */