#ifndef CGAL_KERNELD_SEGMENTD_H
#define CGAL_KERNELD_SEGMENTD_H
#include <utility>
#include <CGAL/functor_tags.h>
#define Segmentd SegmentCd
namespace CGAL {
template <class R_> class Segmentd {
	typedef typename R_::FT FT_;
	typedef typename R_::Point Point_;
	//typedef typename R_::Vector Vector_;
	//typedef typename R_::template Functor<Construct_ttag<Vector_tag> >::type Cv_;
//	typedef typename R_::Compute_squared_distance Csd_;
	typedef std::pair<Point_,Point_> Data_;
	Data_ data;
	public:
	typedef Segmentd<R_> Segment;
#ifdef CGAL_CXX0X
	//FIXME: don't forward directly, piecewise_constuct should call the point construction functor (I guess? or is it unnecessary?)
	template<class...U,class=typename std::enable_if<!std::is_same<std::tuple<typename std::decay<U>::type...>,std::tuple<Segmentd>>::value>::type>
	Segmentd(U&&...u):data(std::forward<U>(u)...){}
#else
	Segmentd(){}
	Segmentd(Point_ const&a, Point_ const&b): data(a,b) {}
	//template<class A,class T1,class T2>
	  //Segmentd(A const&,T1 const&t1,T2 const&t2)
#endif
	Point_ source()const{return data.first;}
	Point_ target()const{return data.second;}
	Point_ operator[](int i)const{
		if((i%2)==0)
			return source();
		else
			return target();
	}
	Segmentd opposite()const{
		return Segmentd(target(),source());
	}
	//Vector_ vector()const{
	//	return Cv_()(data.first,data.second);
	//}
//	FT_ squared_length()const{
//		return Csd_()(data.first,data.second);
//	}
};

} // namespace CGAL

#undef Segmentd
#endif // CGAL_KERNELD_SEGMENTD_H