ceph/src/boost/boost/geometry/index/detail/tuples.hpp

   1 // Boost.Geometry Index
   2 //
   3 // Copyright (c) 2011-2013 Adam Wulkiewicz, Lodz, Poland.
   4 //
   5 // Use, modification and distribution is subject to the Boost Software License,
   6 // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
   7 // http://www.boost.org/LICENSE_1_0.txt)
   8
   9 #ifndef BOOST_GEOMETRY_INDEX_DETAIL_TUPLES_HPP
  10 #define BOOST_GEOMETRY_INDEX_DETAIL_TUPLES_HPP
  11
  12 #include <boost/tuple/tuple.hpp>
  13 #include <boost/type_traits/is_same.hpp>
  14
  15 // TODO move this to index/tuples and separate algorithms
  16
  17 namespace boost { namespace geometry { namespace index { namespace detail {
  18
  19 namespace tuples {
  20
  21 // find_index
  22
  23 namespace detail {
  24
  25 template <typename Tuple, typename El, size_t N>
  26 struct find_index;
  27
  28 template <typename Tuple, typename El, size_t N, typename CurrentEl>
  29 struct find_index_impl
  30 {
  31     static const size_t value = find_index<Tuple, El, N - 1>::value;
  32 };
  33
  34 template <typename Tuple, typename El, size_t N>
  35 struct find_index_impl<Tuple, El, N, El>
  36 {
  37     static const size_t value = N - 1;
  38 };
  39
  40 template <typename Tuple, typename El, typename CurrentEl>
  41 struct find_index_impl<Tuple, El, 1, CurrentEl>
  42 {
  43     BOOST_MPL_ASSERT_MSG(
  44         (false),
  45         ELEMENT_NOT_FOUND,
  46         (find_index_impl));
  47 };
  48
  49 template <typename Tuple, typename El>
  50 struct find_index_impl<Tuple, El, 1, El>
  51 {
  52     static const size_t value = 0;
  53 };
  54
  55 template <typename Tuple, typename El, size_t N>
  56 struct find_index
  57 {
  58     static const size_t value =
  59         find_index_impl<
  60             Tuple,
  61             El,
  62             N,
  63             typename boost::tuples::element<N - 1, Tuple>::type
  64         >::value;
  65 };
  66
  67 } // namespace detail
  68
  69 template <typename Tuple, typename El>
  70 struct find_index
  71 {
  72     static const size_t value =
  73         detail::find_index<
  74             Tuple,
  75             El,
  76             boost::tuples::length<Tuple>::value
  77         >::value;
  78 };
  79
  80 // has
  81
  82 namespace detail {
  83
  84 template <typename Tuple, typename El, size_t N>
  85 struct has
  86 {
  87     static const bool value
  88         = boost::is_same<
  89             typename boost::tuples::element<N - 1, Tuple>::type,
  90             El
  91         >::value
  92         || has<Tuple, El, N - 1>::value;
  93 };
  94
  95 template <typename Tuple, typename El>
  96 struct has<Tuple, El, 1>
  97 {
  98     static const bool value
  99         = boost::is_same<
 100             typename boost::tuples::element<0, Tuple>::type,
 101             El
 102         >::value;
 103 };
 104
 105 } // namespace detail
 106
 107 template <typename Tuple, typename El>
 108 struct has
 109 {
 110     static const bool value
 111         = detail::has<
 112             Tuple,
 113             El,
 114             boost::tuples::length<Tuple>::value
 115         >::value;
 116 };
 117
 118 // add
 119
 120 template <typename Tuple, typename El>
 121 struct add
 122 {
 123     BOOST_MPL_ASSERT_MSG(
 124         (false),
 125         NOT_IMPLEMENTED_FOR_THIS_TUPLE_TYPE,
 126         (add));
 127 };
 128
 129 template <typename T1, typename T>
 130 struct add<boost::tuple<T1>, T>
 131 {
 132     typedef boost::tuple<T1, T> type;
 133 };
 134
 135 template <typename T1, typename T2, typename T>
 136 struct add<boost::tuple<T1, T2>, T>
 137 {
 138     typedef boost::tuple<T1, T2, T> type;
 139 };
 140
 141 // add_if
 142
 143 template <typename Tuple, typename El, bool Cond>
 144 struct add_if
 145 {
 146     typedef Tuple type;
 147 };
 148
 149 template <typename Tuple, typename El>
 150 struct add_if<Tuple, El, true>
 151 {
 152     typedef typename add<Tuple, El>::type type;
 153 };
 154
 155 // add_unique
 156
 157 template <typename Tuple, typename El>
 158 struct add_unique
 159 {
 160     typedef typename add_if<
 161         Tuple,
 162         El,
 163         !has<Tuple, El>::value
 164     >::type type;
 165 };
 166
 167 template <typename Tuple,
 168           typename T,
 169           size_t I = 0,
 170           size_t N = boost::tuples::length<Tuple>::value>
 171 struct push_back
 172 {
 173     typedef
 174     boost::tuples::cons<
 175         typename boost::tuples::element<I, Tuple>::type,
 176         typename push_back<Tuple, T, I+1, N>::type
 177     > type;
 178
 179     static type apply(Tuple const& tup, T const& t)
 180     {
 181         return
 182         type(
 183             boost::get<I>(tup),
 184             push_back<Tuple, T, I+1, N>::apply(tup, t)
 185         );
 186     }
 187 };
 188
 189 template <typename Tuple, typename T, size_t N>
 190 struct push_back<Tuple, T, N, N>
 191 {
 192     typedef boost::tuples::cons<T, boost::tuples::null_type> type;
 193
 194     static type apply(Tuple const&, T const& t)
 195     {
 196         return type(t, boost::tuples::null_type());
 197     }
 198 };
 199
 200 } // namespace tuples
 201
 202 }}}} // namespace boost::geometry::index::detail
 203
 204 #endif // BOOST_GEOMETRY_INDEX_DETAIL_RTREE_TAGS_HPP