projects / ceph.git / blame
| Commit | Line | Data |
|---|---|---|
| 11fdf7f2 TL |
1 | // Boost.Geometry |
| 2 | ||
| 3 | // Copyright (c) 2017 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_UTIL_SELECT_SEQUENCE_ELEMENT | |
| 10 | #define BOOST_GEOMETRY_UTIL_SELECT_SEQUENCE_ELEMENT | |
| 11 | ||
| 12 | ||
| 13 | #include <boost/mpl/if.hpp> | |
| 14 | #include <boost/mpl/int.hpp> | |
| 15 | #include <boost/mpl/at.hpp> | |
| 16 | #include <boost/mpl/size.hpp> | |
| 17 | ||
| 18 | #include <boost/type_traits/is_same.hpp> | |
| 19 | ||
| 20 | #include <boost/geometry/core/coordinate_type.hpp> | |
| 21 | #include <boost/geometry/util/select_most_precise.hpp> | |
| 22 | ||
| 23 | ||
| 24 | namespace boost { namespace geometry | |
| 25 | { | |
| 26 | ||
| 27 | namespace util | |
| 28 | { | |
| 29 | ||
| 30 | template <typename Curr, typename Next> | |
| 31 | struct pred_more_precise_coordinate_type | |
| 32 | { | |
| 33 | typedef typename geometry::coordinate_type<Curr>::type curr_coord_t; | |
| 34 | typedef typename geometry::coordinate_type<Next>::type next_coord_t; | |
| 35 | ||
| 36 | typedef typename boost::mpl::if_c | |
| 37 | < | |
| 38 | boost::is_same | |
| 39 | < | |
| 40 | curr_coord_t, | |
| 41 | typename select_most_precise | |
| 42 | < | |
| 43 | curr_coord_t, | |
| 44 | next_coord_t | |
| 45 | >::type | |
| 46 | >::value, | |
| 47 | Curr, | |
| 48 | Next | |
| 49 | >::type type; | |
| 50 | }; | |
| 51 | ||
| 52 | template | |
| 53 | < | |
| 54 | typename Seq, | |
| 55 | template<typename, typename> class Pred = pred_more_precise_coordinate_type, | |
| 56 | int I = 0, | |
| 57 | int N = boost::mpl::size<Seq>::value | |
| 58 | > | |
| 59 | struct select_sequence_element | |
| 60 | { | |
| 61 | typedef typename boost::mpl::at<Seq, boost::mpl::int_<I> >::type curr_t; | |
| 62 | typedef typename select_sequence_element<Seq, Pred, I+1, N>::type next_t; | |
| 63 | ||
| 64 | typedef typename Pred<curr_t, next_t>::type type; | |
| 65 | }; | |
| 66 | ||
| 67 | template <typename Seq, template<typename, typename> class Pred, int N> | |
| 68 | struct select_sequence_element<Seq, Pred, N, N> | |
| 69 | { | |
| 70 | typedef typename boost::mpl::at<Seq, boost::mpl::int_<N-1> >::type type; | |
| 71 | }; | |
| 72 | ||
| 73 | } // namespace util | |
| 74 | ||
| 75 | }} // namespace boost::geometry | |
| 76 | ||
| 77 | ||
| 78 | #endif // BOOST_GEOMETRY_UTIL_SELECT_SEQUENCE_ELEMENT |