move/detail/iterator_traits.hpp

0001 //////////////////////////////////////////////////////////////////////////////
0002 //
0003 // (C) Copyright Ion Gaztanaga 2014-2014.
0004 // Distributed under the Boost Software License, Version 1.0.
0005 // (See accompanying file LICENSE_1_0.txt or copy at
0006 // http://www.boost.org/LICENSE_1_0.txt)
0007 //
0008 // See http://www.boost.org/libs/move for documentation.
0009 //
0010 //////////////////////////////////////////////////////////////////////////////
0011
0012 //! \file
0013
0014 #ifndef BOOST_MOVE_DETAIL_ITERATOR_TRAITS_HPP
0015 #define BOOST_MOVE_DETAIL_ITERATOR_TRAITS_HPP
0016
0017 #ifndef BOOST_CONFIG_HPP
0018 #  include <boost/config.hpp>
0019 #endif
0020 #
0021 #if defined(BOOST_HAS_PRAGMA_ONCE)
0022 #  pragma once
0023 #endif
0024
0025 #if (BOOST_CXX_VERSION > 201703L) && defined(__cpp_lib_concepts)
0026
0027 #include <iterator>
0028
0029 #define BOOST_MOVE_CONTIGUOUS_ITERATOR_TAG
0030
0031 namespace boost {
0032 namespace movelib {
0033
0034    using std::iterator_traits;
0035
0036    template<class T>
0037    struct iter_difference
0038    {
0039       typedef typename std::iterator_traits<T>::difference_type type;
0040    };
0041
0042    template<class T>
0043    struct iter_value
0044    {
0045       typedef typename std::iterator_traits<T>::value_type type;
0046    };
0047
0048    template<class T>
0049    struct iter_category
0050    {
0051       typedef typename std::iterator_traits<T>::iterator_category type;
0052    };
0053
0054 }} //namespace boost::movelib
0055
0056 #else
0057
0058 #include <cstddef>
0059 #include <boost/move/detail/type_traits.hpp>
0060
0061 #include <boost/move/detail/std_ns_begin.hpp>
0062
0063 BOOST_MOVE_STD_NS_BEG
0064
0065 struct input_iterator_tag;
0066 struct forward_iterator_tag;
0067 struct bidirectional_iterator_tag;
0068 struct random_access_iterator_tag;
0069 struct output_iterator_tag;
0070
0071 #if (  (defined(BOOST_GNU_STDLIB) && (__cplusplus > 201703L))\
0072     || (defined(_LIBCPP_VERSION) && (_LIBCPP_STD_VER > 17))\
0073     || (defined(_YVALS) && defined(_CPPLIB_VER) && defined(__cpp_lib_concepts))\
0074     || (__cplusplus >= 202002L)\
0075     )
0076 #  define BOOST_MOVE_CONTIGUOUS_ITERATOR_TAG
0077 struct contiguous_iterator_tag;
0078
0079 #endif
0080
0081 BOOST_MOVE_STD_NS_END
0082
0083 #include <boost/move/detail/std_ns_end.hpp>
0084
0085 namespace boost{  namespace movelib{
0086
0087 template<class T>
0088 struct iter_difference
0089 {
0090    typedef typename T::difference_type type;
0091 };
0092
0093 template<class T>
0094 struct iter_difference<T*>
0095 {
0096    typedef std::ptrdiff_t type;
0097 };
0098
0099 template<class T>
0100 struct iter_value
0101 {
0102    typedef typename T::value_type type;
0103 };
0104
0105 template<class T>
0106 struct iter_value<T*>
0107 {
0108    typedef T type;
0109 };
0110
0111 template<class T>
0112 struct iter_value<const T*>
0113 {
0114    typedef T type;
0115 };
0116
0117 template<class T>
0118 struct iter_category
0119 {
0120    typedef typename T::iterator_category type;
0121 };
0122
0123
0124 template<class T>
0125 struct iter_category<T*>
0126 {
0127    typedef std::random_access_iterator_tag type;
0128 };
0129
0130 template<class Iterator>
0131 struct iterator_traits
0132 {
0133    typedef typename iter_difference<Iterator>::type   difference_type;
0134    typedef typename iter_value<Iterator>::type        value_type;
0135    typedef typename Iterator::pointer                 pointer;
0136    typedef typename Iterator::reference               reference;
0137    typedef typename iter_category<Iterator>::type     iterator_category;
0138 };
0139
0140 template<class T>
0141 struct iterator_traits<T*>
0142 {
0143    typedef std::ptrdiff_t                    difference_type;
0144    typedef T                                 value_type;
0145    typedef T*                                pointer;
0146    typedef T&                                reference;
0147    typedef std::random_access_iterator_tag   iterator_category;
0148 };
0149
0150 template<class T>
0151 struct iterator_traits<const T*>
0152 {
0153    typedef std::ptrdiff_t                    difference_type;
0154    typedef T                                 value_type;
0155    typedef const T*                          pointer;
0156    typedef const T&                          reference;
0157    typedef std::random_access_iterator_tag   iterator_category;
0158 };
0159
0160 }} //namespace boost::movelib
0161
0162 #endif   //
0163
0164 #include <boost/move/detail/type_traits.hpp>
0165
0166 namespace boost {
0167 namespace movelib {
0168
0169 template<class T>
0170 struct iter_size
0171    : boost::move_detail::
0172       make_unsigned<typename iter_difference<T>::type >
0173 {};
0174
0175 }}  //namespace boost move_detail {
0176
0177 #endif //#ifndef BOOST_MOVE_DETAIL_ITERATOR_TRAITS_HPP