From 35b3b09ab81beafb96ce67609de707ebd7097a6e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Fr=C3=A9d=C3=A9rik=20Paradis?= <fredy_14@live.fr>
Date: Sat, 14 May 2016 14:28:51 -0400
Subject: [PATCH] Adding less-than operator (<) to Point_d

---
 Kernel_d/doc/Kernel_d/CGAL/Kernel_d/Point_d.h | 32 +++++++++++++++++++
 Kernel_d/include/CGAL/Kernel_d/Point_d.h      |  8 +++++
 2 files changed, 40 insertions(+)

diff --git a/Kernel_d/doc/Kernel_d/CGAL/Kernel_d/Point_d.h b/Kernel_d/doc/Kernel_d/CGAL/Kernel_d/Point_d.h
index 772363a625b..b1493b3fda6 100644
--- a/Kernel_d/doc/Kernel_d/CGAL/Kernel_d/Point_d.h
+++ b/Kernel_d/doc/Kernel_d/CGAL/Kernel_d/Point_d.h
@@ -241,6 +241,38 @@ the origin.
 */ 
 bool operator==(const Origin&) ; 
 
+/*!
+returns true iff `p` is lexicographically
+smaller than `q` with respect to %Cartesian
+lexicographic order of points.
+\pre `p.dimension() == q.dimension()`.
+*/
+bool operator<(const Point_d<Kernel>& q);
+
+/*!
+returns true iff `p` is lexicographically
+greater than `q` with respect to %Cartesian
+lexicographic order of points.
+\pre `p.dimension() == q.dimension()`.
+*/
+bool operator>(const Point_d<Kernel>& q);
+
+/*!
+returns true iff `p` is lexicographically
+smaller than or equal to `q` with respect to %Cartesian
+lexicographic order of points.
+\pre `p.dimension() == q.dimension()`.
+*/
+bool operator<=(const Point_d<Kernel>& q);
+
+/*!
+returns true iff `p` is lexicographically
+greater than or equal to `q` with respect to %Cartesian
+lexicographic order of points.
+\pre `p.dimension() == q.dimension()`.
+*/
+bool operator>=(const Point_d<Kernel>& q);
+
 /// @}
 
 }; /* end Point_d */
diff --git a/Kernel_d/include/CGAL/Kernel_d/Point_d.h b/Kernel_d/include/CGAL/Kernel_d/Point_d.h
index 6f9434609b9..703a8202173 100644
--- a/Kernel_d/include/CGAL/Kernel_d/Point_d.h
+++ b/Kernel_d/include/CGAL/Kernel_d/Point_d.h
@@ -93,6 +93,14 @@ public:
   Self& operator-=(const Vector_d<R>& v)
   { return static_cast<Self&>(Base::operator-=(v)); }
   
+  inline bool operator<(const Self& q) const
+  { return R().less_lexicographically_d_object()(*this, q); }
+  inline bool operator>(const Self& q) const
+  { return R().less_lexicographically_d_object()(q, *this); }
+  inline bool operator<=(const Self& q) const
+  { return ! R().less_lexicographically_d_object()(q, *this); }
+  inline bool operator>=(const Self& q) const
+  { return ! R().less_lexicographically_d_object()(*this, q); }
 };
 
 } //namespace CGAL