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diff --git a/boost/geometry/index/detail/algorithms/path_intersection.hpp b/boost/geometry/index/detail/algorithms/path_intersection.hpp
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+++ b/boost/geometry/index/detail/algorithms/path_intersection.hpp
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+// Boost.Geometry Index
+//
+// n-dimensional box-linestring intersection
+//
+// Copyright (c) 2011-2014 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_INDEX_DETAIL_ALGORITHMS_PATH_INTERSECTION_HPP
+#define BOOST_GEOMETRY_INDEX_DETAIL_ALGORITHMS_PATH_INTERSECTION_HPP
+
+#include <boost/geometry/index/detail/algorithms/segment_intersection.hpp>
+
+namespace boost { namespace geometry { namespace index { namespace detail {
+
+namespace dispatch {
+
+template <typename Indexable, typename Geometry, typename IndexableTag, typename GeometryTag>
+struct path_intersection
+{
+    BOOST_MPL_ASSERT_MSG((false), NOT_IMPLEMENTED_FOR_THIS_GEOMETRY_OR_INDEXABLE, (path_intersection));
+};
+
+// TODO: FP type must be used as a relative distance type!
+// and default_distance_result can be some user-defined int type
+// BUT! This code is experimental and probably won't be released at all
+// since more flexible user-defined-nearest predicate should be added instead
+
+template <typename Indexable, typename Segment>
+struct path_intersection<Indexable, Segment, box_tag, segment_tag>
+{
+    typedef typename default_distance_result<typename point_type<Segment>::type>::type comparable_distance_type;
+
+    static inline bool apply(Indexable const& b, Segment const& segment, comparable_distance_type & comparable_distance)
+    {
+        typedef typename point_type<Segment>::type point_type;
+        point_type p1, p2;
+        geometry::detail::assign_point_from_index<0>(segment, p1);
+        geometry::detail::assign_point_from_index<1>(segment, p2);
+        return index::detail::segment_intersection(b, p1, p2, comparable_distance);
+    }
+};
+
+template <typename Indexable, typename Linestring>
+struct path_intersection<Indexable, Linestring, box_tag, linestring_tag>
+{
+    typedef typename default_length_result<Linestring>::type comparable_distance_type;
+
+    static inline bool apply(Indexable const& b, Linestring const& path, comparable_distance_type & comparable_distance)
+    {
+        typedef typename ::boost::range_value<Linestring>::type point_type;
+        typedef typename ::boost::range_const_iterator<Linestring>::type const_iterator;        
+        typedef typename ::boost::range_size<Linestring>::type size_type;
+        
+        const size_type count = ::boost::size(path);
+
+        if ( count == 2 )
+        {
+            return index::detail::segment_intersection(b, *::boost::begin(path), *(::boost::begin(path)+1), comparable_distance);
+        }
+        else if ( 2 < count )
+        {
+            const_iterator it0 = ::boost::begin(path);
+            const_iterator it1 = ::boost::begin(path) + 1;
+            const_iterator last = ::boost::end(path);
+
+            comparable_distance = 0;
+
+            for ( ; it1 != last ; ++it0, ++it1 )
+            {
+                typename default_distance_result<point_type, point_type>::type
+                    dist = geometry::distance(*it0, *it1);
+
+                comparable_distance_type rel_dist;
+                if ( index::detail::segment_intersection(b, *it0, *it1, rel_dist) )
+                {
+                    comparable_distance += dist * rel_dist;
+                    return true;
+                }
+                else
+                    comparable_distance += dist;
+            }
+        }
+
+        return false;
+    }
+};
+
+} // namespace dispatch
+
+template <typename Indexable, typename SegmentOrLinestring>
+struct default_path_intersection_distance_type
+{
+    typedef typename dispatch::path_intersection<
+        Indexable, SegmentOrLinestring,
+        typename tag<Indexable>::type,
+        typename tag<SegmentOrLinestring>::type
+    >::comparable_distance_type type;
+};
+
+template <typename Indexable, typename SegmentOrLinestring> inline
+bool path_intersection(Indexable const& b,
+                       SegmentOrLinestring const& path,
+                       typename default_path_intersection_distance_type<Indexable, SegmentOrLinestring>::type & comparable_distance)
+{
+    // TODO check Indexable and Linestring concepts
+
+    return dispatch::path_intersection<
+            Indexable, SegmentOrLinestring,
+            typename tag<Indexable>::type,
+            typename tag<SegmentOrLinestring>::type
+        >::apply(b, path, comparable_distance);
+}
+
+}}}} // namespace boost::geometry::index::detail
+
+#endif // BOOST_GEOMETRY_INDEX_DETAIL_ALGORITHMS_PATH_INTERSECTION_HPP