
//  (C) Copyright John Maddock 2007.
//  Use, modification and distribution are subject to the Boost Software License,
//  Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
//  http://www.boost.org/LICENSE_1_0.txt).
//
//  See http://www.boost.org/libs/type_traits for most recent version including documentation.

#ifndef BOOST_TT_MAKE_UNSIGNED_HPP_INCLUDED
#define BOOST_TT_MAKE_UNSIGNED_HPP_INCLUDED

#include <boost/type_traits/conditional.hpp>
#include <boost/type_traits/is_integral.hpp>
#include <boost/type_traits/is_signed.hpp>
#include <boost/type_traits/is_unsigned.hpp>
#include <boost/type_traits/is_enum.hpp>
#include <boost/type_traits/is_same.hpp>
#include <boost/type_traits/remove_cv.hpp>
#include <boost/type_traits/is_const.hpp>
#include <boost/type_traits/is_volatile.hpp>
#include <boost/type_traits/add_const.hpp>
#include <boost/type_traits/add_volatile.hpp>
#include <boost/static_assert.hpp>

namespace boost {

template <class T>
struct make_unsigned
{
  private:
    BOOST_STATIC_ASSERT_MSG((::boost::is_integral<T>::value || ::boost::is_enum<T>::value), "The template argument to make_unsigned must be an integer or enum type.");
    BOOST_STATIC_ASSERT_MSG((! ::boost::is_same<typename remove_cv<T>::type, bool>::value), "The template argument to make_unsigned must not be the type bool");

    typedef typename remove_cv<T>::type t_no_cv;
    typedef typename conditional<
    (::boost::is_unsigned<T>::value && ::boost::is_integral<T>::value
     && ! ::boost::is_same<t_no_cv, char>::value
     && ! ::boost::is_same<t_no_cv, wchar_t>::value
     && ! ::boost::is_same<t_no_cv, bool>::value),
     T,
     typename conditional<
     (::boost::is_integral<T>::value
      && ! ::boost::is_same<t_no_cv, char>::value
      && ! ::boost::is_same<t_no_cv, wchar_t>::value
      && ! ::boost::is_same<t_no_cv, bool>::value),
     typename conditional<
     is_same<t_no_cv, signed char>::value,
     unsigned char,
     typename conditional<
     is_same<t_no_cv, short>::value,
     unsigned short,
     typename conditional<
     is_same<t_no_cv, int>::value,
     unsigned int,
     typename conditional<
     is_same<t_no_cv, long>::value,
     unsigned long,
#if defined(BOOST_HAS_LONG_LONG)
#ifdef BOOST_HAS_INT128
     typename conditional<
     sizeof(t_no_cv) == sizeof(boost::ulong_long_type),
     boost::ulong_long_type,
     boost::uint128_type
     >::type
#else
     boost::ulong_long_type
#endif
#elif defined(BOOST_HAS_MS_INT64)
     unsigned __int64
#else
     unsigned long
#endif
     >::type
     >::type
     >::type
     >::type,
     // Not a regular integer type:
     typename conditional<
     sizeof(t_no_cv) == sizeof(unsigned char),
     unsigned char,
     typename conditional<
     sizeof(t_no_cv) == sizeof(unsigned short),
     unsigned short,
     typename conditional<
     sizeof(t_no_cv) == sizeof(unsigned int),
     unsigned int,
     typename conditional<
     sizeof(t_no_cv) == sizeof(unsigned long),
     unsigned long,
#if defined(BOOST_HAS_LONG_LONG)
#ifdef BOOST_HAS_INT128
     typename conditional<
     sizeof(t_no_cv) == sizeof(boost::ulong_long_type),
     boost::ulong_long_type,
     boost::uint128_type
     >::type
#else
     boost::ulong_long_type
#endif
#elif defined(BOOST_HAS_MS_INT64)
     unsigned __int64
#else
     unsigned long
#endif
     >::type
     >::type
     >::type
     >::type
     >::type
     >::type base_integer_type;

    // Add back any const qualifier:
    typedef typename conditional<
    is_const<T>::value,
             typename add_const<base_integer_type>::type,
             base_integer_type
             >::type const_base_integer_type;
  public:
    // Add back any volatile qualifier:
    typedef typename conditional<
    is_volatile<T>::value,
                typename add_volatile<const_base_integer_type>::type,
                const_base_integer_type
                >::type type;
};

#if !defined(BOOST_NO_CXX11_TEMPLATE_ALIASES)

template <class T> using make_unsigned_t = typename make_unsigned<T>::type;

#endif

} // namespace boost

#endif // BOOST_TT_ADD_REFERENCE_HPP_INCLUDED
