/// \defgroup PkgIntervalSkipListRef Interval Skip List Reference
/// \defgroup PkgIntervalSkipListConcepts Concepts
/// \ingroup PkgIntervalSkipListRef
/*!
\addtogroup PkgIntervalSkipListRef

\cgalPkgDescriptionBegin{Interval Skip List,PkgIntervalSkipList}
\cgalPkgPicture{Interval_skip_list/fig/query.png}
\cgalPkgSummaryBegin
\cgalPkgAuthor{Andreas Fabri}
\cgalPkgDesc{An interval skip list is a data structure for finding all intervals that contain a point, and for stabbing queries, that is for answering the question whether a given point is contained in an interval or not. For a triangulated terrain, this allows to quickly identify the triangles which intersect an iso line. }
\cgalPkgManuals{Chapter_Interval_Skip_List,PkgIntervalSkipListRef}
\cgalPkgSummaryEnd
\cgalPkgShortInfoBegin
\cgalPkgSince{3.0}
\cgalPkgBib{cgal:f-isl}
\cgalPkgLicense{\ref licensesGPL  "GPL"}
\cgalPkgShortInfoEnd
\cgalPkgDescriptionEnd

This chapter presents the interval skip list introduced by Hanson \cgalCite{h-islds-91},
and derived from the skip list data structure \cgalCite{p-slpab-90}.

The data structure stores intervals and allows to perform stabbing queries,
that is to test whether a point is covered by any of the intervals.
It further allows to find all intervals that contain a point.

The interval skip list is, as far as its functionality is concerned,
related to the `Segment_tree_d`. Both allow to do stabbing queries
and both allow to find all intervals that contain a given point.  The
implementation of segment trees in \cgal works in higher
dimensions, whereas the interval skip list is limited to the 1D
case. However, this interval skip list implementation is fully
dynamic, whereas the segment tree implementation in \cgal is
static, that is all intervals must be known in advance.

This package has one concept, namely for the interval with which 
the interval skip list class is parameterized.

\cgalClassifedRefPages

\cgalCRPSection{Concepts}
- `Interval`

\cgalCRPSection{Classes}
- `CGAL::Interval_skip_list<Interval>`
- `CGAL::Interval_skip_list_interval<Value>`
- `CGAL::Level_interval<FaceHandle>`

*/

