123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778 |
- // Boost.Geometry
- // Copyright (c) 2017 Adam Wulkiewicz, Lodz, Poland.
- // Use, modification and distribution is 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)
- #ifndef BOOST_GEOMETRY_UTIL_SELECT_SEQUENCE_ELEMENT
- #define BOOST_GEOMETRY_UTIL_SELECT_SEQUENCE_ELEMENT
- #include <boost/mpl/if.hpp>
- #include <boost/mpl/int.hpp>
- #include <boost/mpl/at.hpp>
- #include <boost/mpl/size.hpp>
- #include <boost/type_traits/is_same.hpp>
- #include <boost/geometry/core/coordinate_type.hpp>
- #include <boost/geometry/util/select_most_precise.hpp>
- namespace boost { namespace geometry
- {
- namespace util
- {
- template <typename Curr, typename Next>
- struct pred_more_precise_coordinate_type
- {
- typedef typename geometry::coordinate_type<Curr>::type curr_coord_t;
- typedef typename geometry::coordinate_type<Next>::type next_coord_t;
- typedef typename boost::mpl::if_c
- <
- boost::is_same
- <
- curr_coord_t,
- typename select_most_precise
- <
- curr_coord_t,
- next_coord_t
- >::type
- >::value,
- Curr,
- Next
- >::type type;
- };
- template
- <
- typename Seq,
- template<typename, typename> class Pred = pred_more_precise_coordinate_type,
- int I = 0,
- int N = boost::mpl::size<Seq>::value
- >
- struct select_sequence_element
- {
- typedef typename boost::mpl::at<Seq, boost::mpl::int_<I> >::type curr_t;
- typedef typename select_sequence_element<Seq, Pred, I+1, N>::type next_t;
- typedef typename Pred<curr_t, next_t>::type type;
- };
- template <typename Seq, template<typename, typename> class Pred, int N>
- struct select_sequence_element<Seq, Pred, N, N>
- {
- typedef typename boost::mpl::at<Seq, boost::mpl::int_<N-1> >::type type;
- };
- } // namespace util
- }} // namespace boost::geometry
- #endif // BOOST_GEOMETRY_UTIL_SELECT_SEQUENCE_ELEMENT
|