diff --git a/STL_Extension/include/CGAL/iterator.h b/STL_Extension/include/CGAL/iterator.h
index 8d4bc009747..5e86e9c4561 100644
--- a/STL_Extension/include/CGAL/iterator.h
+++ b/STL_Extension/include/CGAL/iterator.h
@@ -37,28 +37,28 @@
 
 namespace CGAL {
 
-  template<typename I, typename VT = I>
+template<typename I, typename Value_type = I>
 class Prevent_deref
   : public boost::iterator_adaptor<
-    Prevent_deref<I,VT>
+    Prevent_deref<I,Value_type>
   , I // base
-  , VT // value
+  , Value_type // value
   , boost::use_default
-  , VT // ref
+  , Value_type // ref
   >
 {
 public:
   typedef boost::iterator_adaptor<
-  Prevent_deref<I,VT>
+  Prevent_deref<I,Value_type>
   , I // base
-  , VT // value
+  , Value_type // value
   , boost::use_default
-  , VT // ref
+  , Value_type // ref
   > Base;
   typedef typename Base::reference reference;
   typedef typename std::pair<I, I> range;
 
-  Prevent_deref() : Base() {}
+  Prevent_deref() = default;
   Prevent_deref(const I& i) : Base(i) {}
 private:
   friend class boost::iterator_core_access;
@@ -67,11 +67,6 @@ private:
   }
 };
 
-
-
-
-
-
 template<typename I>
 Iterator_range<Prevent_deref<I> > make_prevent_deref_range(const Iterator_range<I>& range)
 {
diff --git a/TDS_2/include/CGAL/Triangulation_data_structure_2.h b/TDS_2/include/CGAL/Triangulation_data_structure_2.h
index aff81d0302c..f7c386b9d3f 100644
--- a/TDS_2/include/CGAL/Triangulation_data_structure_2.h
+++ b/TDS_2/include/CGAL/Triangulation_data_structure_2.h
@@ -183,7 +183,7 @@ public:
   }
 
   Face_handles face_handles() const {
-    return { faces_begin(),faces_end() };
+    return { faces_begin(), faces_end() };
   }
 
   Vertex_iterator vertices_begin() const  {
@@ -195,7 +195,7 @@ public:
   }
 
   Vertex_handles vertex_handles() const {
-    return { vertices_begin(),vertices_end() };
+    return { vertices_begin(), vertices_end() };
   }
 
   Edge_iterator edges_begin() const {
diff --git a/TDS_3/include/CGAL/Triangulation_data_structure_3.h b/TDS_3/include/CGAL/Triangulation_data_structure_3.h
index ab4806a9abc..62885f68043 100644
--- a/TDS_3/include/CGAL/Triangulation_data_structure_3.h
+++ b/TDS_3/include/CGAL/Triangulation_data_structure_3.h
@@ -661,7 +661,7 @@ public:
 
   Cell_handles cell_handles() const
   {
-    return {cells_begin(), cells_end()};
+    return { cells_begin(), cells_end() };
   }
 
   Cell_iterator raw_cells_begin() const
@@ -720,7 +720,7 @@ public:
 
   Vertex_handles vertex_handles() const
   {
-    return {vertices_begin(), vertices_end()};
+    return { vertices_begin(), vertices_end() };
   }
 
   // CIRCULATOR METHODS
diff --git a/Triangulation_2/include/CGAL/Regular_triangulation_2.h b/Triangulation_2/include/CGAL/Regular_triangulation_2.h
index 553f6b50285..38a46d93826 100644
--- a/Triangulation_2/include/CGAL/Regular_triangulation_2.h
+++ b/Triangulation_2/include/CGAL/Regular_triangulation_2.h
@@ -183,7 +183,8 @@ public:
     operator Vertex_handle() const { return Base::base(); }
  };
 
-  typedef Iterator_range<Prevent_deref<Finite_vertices_iterator, Vertex_handle> > Finite_vertex_handles;
+  typedef Iterator_range<Prevent_deref<Finite_vertices_iterator,
+                                       Vertex_handle> > Finite_vertex_handles;
 
   class Hidden_vertices_iterator :
     public Filter_iterator<Finite_vib, Unhidden_tester>
@@ -200,7 +201,8 @@ public:
     operator Vertex_handle() const { return Base::base(); }
  };
 
-  typedef Iterator_range<Prevent_deref<Hidden_vertices_iterator,Vertex_handle> > Hidden_vertex_handles;
+  typedef Iterator_range<Prevent_deref<Hidden_vertices_iterator,
+                                       Vertex_handle> > Hidden_vertex_handles;
 
  //for backward compatibility
   typedef Finite_faces_iterator                Face_iterator;
@@ -2236,7 +2238,7 @@ typename Regular_triangulation_2<Gt,Tds>::Finite_vertex_handles
 Regular_triangulation_2<Gt,Tds>::
 finite_vertex_handles() const
 {
-    return { finite_vertices_begin(),finite_vertices_end() };
+    return { finite_vertices_begin(), finite_vertices_end() };
 }
 
 template < class Gt, class Tds >
@@ -2263,7 +2265,7 @@ typename Regular_triangulation_2<Gt,Tds>::Hidden_vertex_handles
 Regular_triangulation_2<Gt,Tds>::
 hidden_vertex_handles() const
 {
-  return { hidden_vertices_begin(),hidden_vertices_end() };
+  return { hidden_vertices_begin(), hidden_vertices_end() };
 }
 
 template < class Gt, class Tds >
diff --git a/Triangulation_2/include/CGAL/Triangulation_2.h b/Triangulation_2/include/CGAL/Triangulation_2.h
index 26d6006820e..6cce9ed2d4e 100644
--- a/Triangulation_2/include/CGAL/Triangulation_2.h
+++ b/Triangulation_2/include/CGAL/Triangulation_2.h
@@ -213,8 +213,10 @@ public:
   typedef typename Tds::Vertex_handles         All_vertex_handles;
   typedef typename Tds::Edges                  All_edges;
 
-  typedef Iterator_range<Prevent_deref<Finite_faces_iterator, Face_handle> >    Finite_face_handles;
-  typedef Iterator_range<Prevent_deref<Finite_vertices_iterator, Vertex_handle> > Finite_vertex_handles;
+  typedef Iterator_range<Prevent_deref<Finite_faces_iterator,
+                                       Face_handle> >   Finite_face_handles;
+  typedef Iterator_range<Prevent_deref<Finite_vertices_iterator,
+                                       Vertex_handle> > Finite_vertex_handles;
   typedef Iterator_range<Finite_edges_iterator>                    Finite_edges;
   typedef Iterator_range<Point_iterator>                           Points;
 
@@ -3206,7 +3208,7 @@ typename Triangulation_2<Gt, Tds>::Finite_face_handles
 Triangulation_2<Gt, Tds>::
 finite_face_handles() const
 {
-  return { finite_faces_begin(),finite_faces_end() };
+  return { finite_faces_begin(), finite_faces_end() };
 }
 
 template <class Gt, class Tds >
@@ -3235,7 +3237,7 @@ typename Triangulation_2<Gt, Tds>::Finite_vertex_handles
 Triangulation_2<Gt, Tds>::
 finite_vertex_handles() const
 {
-  return { finite_vertices_begin(),finite_vertices_end() };
+  return { finite_vertices_begin(), finite_vertices_end() };
 }
 
 template <class Gt, class Tds >
diff --git a/Triangulation_3/include/CGAL/Triangulation_3.h b/Triangulation_3/include/CGAL/Triangulation_3.h
index 86102bacc56..e0ff1bfa01b 100644
--- a/Triangulation_3/include/CGAL/Triangulation_3.h
+++ b/Triangulation_3/include/CGAL/Triangulation_3.h
@@ -517,8 +517,10 @@ public:
     operator Vertex_handle() const { return Base::base(); }
   };
 
-  typedef Iterator_range<Prevent_deref<Finite_cells_iterator, Cell_handle> >    Finite_cell_handles;
-  typedef Iterator_range<Prevent_deref<Finite_vertices_iterator,Vertex_handle> > Finite_vertex_handles;
+  typedef Iterator_range<Prevent_deref<Finite_cells_iterator,
+                                       Cell_handle> >         Finite_cell_handles;
+  typedef Iterator_range<Prevent_deref<Finite_vertices_iterator,
+                                       Vertex_handle> >       Finite_vertex_handles;
 
   typedef Filter_iterator<Edge_iterator, Infinite_tester>     Finite_edges_iterator;
   typedef Filter_iterator<Facet_iterator, Infinite_tester>    Finite_facets_iterator;
@@ -529,7 +531,8 @@ public:
   typedef Triangulation_segment_cell_iterator_3<Self>    Segment_cell_iterator;
   typedef Triangulation_segment_simplex_iterator_3<Self> Segment_simplex_iterator;
 
-  typedef Iterator_range<Prevent_deref<Segment_cell_iterator, Cell_handle> >    Segment_traverser_cell_handles;
+  typedef Iterator_range<Prevent_deref<Segment_cell_iterator,
+                                       Cell_handle> >    Segment_traverser_cell_handles;
   typedef Iterator_range<Segment_simplex_iterator> Segment_traverser_simplices;
 
 private:
@@ -1833,7 +1836,7 @@ public:
 
   Finite_vertex_handles finite_vertex_handles() const
   {
-    return { finite_vertices_begin(), finite_vertices_end()};
+    return {finite_vertices_begin(), finite_vertices_end()};
   }
 
   Vertex_iterator vertices_begin() const { return _tds.vertices_begin(); }
@@ -2251,7 +2254,7 @@ public:
                                                                 const Point& pt,
                                                                 Cell_handle hint = Cell_handle()) const
   {
-    return { segment_traverser_cells_begin(ps, pt, hint), segment_traverser_cells_end()};
+    return {segment_traverser_cells_begin(ps, pt, hint), segment_traverser_cells_end()};
   }
 
   //// Segment Simplex Iterator