boost/type_traits/make_unsigned.hpp

0001
0002 //  (C) Copyright John Maddock 2007.
0003 //  Use, modification and distribution are subject to the Boost Software License,
0004 //  Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
0005 //  http://www.boost.org/LICENSE_1_0.txt).
0006 //
0007 //  See http://www.boost.org/libs/type_traits for most recent version including documentation.
0008
0009 #ifndef BOOST_TT_MAKE_UNSIGNED_HPP_INCLUDED
0010 #define BOOST_TT_MAKE_UNSIGNED_HPP_INCLUDED
0011
0012 #include <boost/type_traits/conditional.hpp>
0013 #include <boost/type_traits/is_integral.hpp>
0014 #include <boost/type_traits/is_signed.hpp>
0015 #include <boost/type_traits/is_unsigned.hpp>
0016 #include <boost/type_traits/is_enum.hpp>
0017 #include <boost/type_traits/is_same.hpp>
0018 #include <boost/type_traits/remove_cv.hpp>
0019 #include <boost/type_traits/is_const.hpp>
0020 #include <boost/type_traits/is_volatile.hpp>
0021 #include <boost/type_traits/add_const.hpp>
0022 #include <boost/type_traits/add_volatile.hpp>
0023 #include <boost/static_assert.hpp>
0024
0025 namespace boost {
0026
0027 template <class T>
0028 struct make_unsigned
0029 {
0030 private:
0031    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.");
0032    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");
0033
0034    typedef typename remove_cv<T>::type t_no_cv;
0035    typedef typename conditional<
0036       (::boost::is_unsigned<T>::value && ::boost::is_integral<T>::value
0037       && ! ::boost::is_same<t_no_cv, char>::value
0038       && ! ::boost::is_same<t_no_cv, wchar_t>::value
0039       && ! ::boost::is_same<t_no_cv, bool>::value),
0040       T,
0041       typename conditional<
0042          (::boost::is_integral<T>::value
0043          && ! ::boost::is_same<t_no_cv, char>::value
0044          && ! ::boost::is_same<t_no_cv, wchar_t>::value
0045          && ! ::boost::is_same<t_no_cv, bool>::value),
0046          typename conditional<
0047             is_same<t_no_cv, signed char>::value,
0048             unsigned char,
0049             typename conditional<
0050                is_same<t_no_cv, short>::value,
0051                unsigned short,
0052                typename conditional<
0053                   is_same<t_no_cv, int>::value,
0054                   unsigned int,
0055                   typename conditional<
0056                      is_same<t_no_cv, long>::value,
0057                      unsigned long,
0058 #if defined(BOOST_HAS_LONG_LONG)
0059 #ifdef BOOST_HAS_INT128
0060                      typename conditional<
0061                         sizeof(t_no_cv) == sizeof(boost::ulong_long_type),
0062                         boost::ulong_long_type,
0063                         boost::uint128_type
0064                      >::type
0065 #else
0066                      boost::ulong_long_type
0067 #endif
0068 #elif defined(BOOST_HAS_MS_INT64)
0069                      unsigned __int64
0070 #else
0071                      unsigned long
0072 #endif
0073                   >::type
0074                >::type
0075             >::type
0076          >::type,
0077          // Not a regular integer type:
0078          typename conditional<
0079             sizeof(t_no_cv) == sizeof(unsigned char),
0080             unsigned char,
0081             typename conditional<
0082                sizeof(t_no_cv) == sizeof(unsigned short),
0083                unsigned short,
0084                typename conditional<
0085                   sizeof(t_no_cv) == sizeof(unsigned int),
0086                   unsigned int,
0087                   typename conditional<
0088                      sizeof(t_no_cv) == sizeof(unsigned long),
0089                      unsigned long,
0090 #if defined(BOOST_HAS_LONG_LONG)
0091 #ifdef BOOST_HAS_INT128
0092                      typename conditional<
0093                         sizeof(t_no_cv) == sizeof(boost::ulong_long_type),
0094                         boost::ulong_long_type,
0095                         boost::uint128_type
0096                      >::type
0097 #else
0098                      boost::ulong_long_type
0099 #endif
0100 #elif defined(BOOST_HAS_MS_INT64)
0101                      unsigned __int64
0102 #else
0103                      unsigned long
0104 #endif
0105                   >::type
0106                >::type
0107             >::type
0108          >::type
0109       >::type
0110    >::type base_integer_type;
0111
0112    // Add back any const qualifier:
0113    typedef typename conditional<
0114       is_const<T>::value,
0115       typename add_const<base_integer_type>::type,
0116       base_integer_type
0117    >::type const_base_integer_type;
0118 public:
0119    // Add back any volatile qualifier:
0120    typedef typename conditional<
0121       is_volatile<T>::value,
0122       typename add_volatile<const_base_integer_type>::type,
0123       const_base_integer_type
0124    >::type type;
0125 };
0126
0127 #if !defined(BOOST_NO_CXX11_TEMPLATE_ALIASES)
0128
0129    template <class T> using make_unsigned_t = typename make_unsigned<T>::type;
0130
0131 #endif
0132
0133 } // namespace boost
0134
0135 #endif // BOOST_TT_ADD_REFERENCE_HPP_INCLUDED
0136