text: // Boost.Geometry (aka GGL, Generic Geometry Library)
  
  // Copyright (c) 2008-2011 Bruno Lalande, Paris, France.
  // Copyright (c) 2008-2011 Barend Gehrels, Amsterdam, the Netherlands.
  // Copyright (c) 2009-2011 Mateusz Loskot, London, UK.
  
  // Parts of Boost.Geometry are redesigned from Geodan's Geographic Library
  // (geolib/GGL), copyright (c) 1995-2010 Geodan, Amsterdam, the Netherlands.
  
  // 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_GEOMETRIES_CONCEPTS_LINESTRING_CONCEPT_HPP
  #define BOOST_GEOMETRY_GEOMETRIES_CONCEPTS_LINESTRING_CONCEPT_HPP
  
  
  #include <boost/concept_check.hpp>
  #include <boost/range/concepts.hpp>
  #include <boost/type_traits/remove_const.hpp>
  
  #include <boost/geometry/core/access.hpp>
  #include <boost/geometry/core/mutable_range.hpp>
  #include <boost/geometry/core/point_type.hpp>
  
  #include <boost/geometry/geometries/concepts/point_concept.hpp>
  
  
  
  namespace boost { namespace geometry { namespace concept
  {
  
  
  /*!
  \brief Linestring concept
  \ingroup concepts
  \par Formal definition:
  The linestring concept is defined as following:
  - there must be a specialization of traits::tag defining linestring_tag as type
  - it must behave like a Boost.Range
  - it must implement a std::back_insert_iterator
      - either by implementing push_back
      - or by specializing std::back_insert_iterator
  
  \note to fulfill the concepts, no traits class has to be specialized to
  define the point type.
  
  \par Example:
  
  A custom linestring, defining the necessary specializations to fulfill to the concept.
  
  Suppose that the following linestring is defined:
  \dontinclude doxygen_5.cpp
  \skip custom_linestring1
  \until };
  
  It can then be adapted to the concept as following:
  \dontinclude doxygen_5.cpp
  \skip adapt custom_linestring1
  \until }}
  
  \note
  - There is also the registration macro BOOST_GEOMETRY_REGISTER_LINESTRING
  - For registration of std::vector<P> (and deque, and list) it is enough to
  include the header-file geometries/adapted/std_as_linestring.hpp. That registers
  a vector as a linestring (so it cannot be registered as a linear ring then,
  in the same source code).
  
  
  */
  
  template <typename Geometry>
  class Linestring
  {
  #ifndef DOXYGEN_NO_CONCEPT_MEMBERS
      typedef typename point_type<Geometry>::type point_type;
  
      BOOST_CONCEPT_ASSERT( (concept::Point<point_type>) );
      BOOST_CONCEPT_ASSERT( (boost::RandomAccessRangeConcept<Geometry>) );
  
  public :
  
      BOOST_CONCEPT_USAGE(Linestring)
      {
          Geometry* ls = 0;
          traits::clear<Geometry>::apply(*ls);
          traits::resize<Geometry>::apply(*ls, 0);
          point_type* point = 0;
          traits::push_back<Geometry>::apply(*ls, *point);
      }
  #endif
  };
  
  
  /*!
  \brief Linestring concept (const version)
  \ingroup const_concepts
  \details The ConstLinestring concept check the same as the Linestring concept,
  but does not check write access.
  */
  template <typename Geometry>
  class ConstLinestring
  {
  #ifndef DOXYGEN_NO_CONCEPT_MEMBERS
      typedef typename point_type<Geometry>::type point_type;
  
      BOOST_CONCEPT_ASSERT( (concept::ConstPoint<point_type>) );
      //BOOST_CONCEPT_ASSERT( (boost::RandomAccessRangeConcept<Geometry>) );
      // Relaxed the concept.
      BOOST_CONCEPT_ASSERT( (boost::ForwardRangeConcept<Geometry>) );
  
  
  public :
  
      BOOST_CONCEPT_USAGE(ConstLinestring)
      {
      }
  #endif
  };
  
  }}} // namespace boost::geometry::concept
  
  
  #endif // BOOST_GEOMETRY_GEOMETRIES_CONCEPTS_LINESTRING_CONCEPT_HPP
  