remove CGAL/result_of.h and move its content to config.h

Generator/include/CGAL/internal/Generic_random_point_generator.h

@@ -18,7 +18,6 @@
 #include <CGAL/generators.h>
 #include <CGAL/Random.h>
 #include <CGAL/property_map.h>
-#include <CGAL/result_of.h>
 
 
 #include <vector>

Installation/include/CGAL/config.h

@@ -623,7 +623,6 @@ using std::max;
 #  include <unordered_set>
 #  include <unordered_map>
 #  include <functional>
-#  include <CGAL/result_of.h>
 //
 namespace CGAL {
 //
@@ -642,6 +641,13 @@ namespace CGAL {
     using std::is_enum;
     using std::unordered_set;
     using std::unordered_map;
+#if CGAL_CXX20 || __cpp_lib_is_invocable>=201703L
+    template<typename Signature> class result_of;
+    template<typename F, typename... Args>
+    class result_of<F(Args...)> : public std::invoke_result<F, Args...> { };
+#else
+    using std::result_of;
+#endif
   }
 //
   namespace cpp0x = cpp11;

Periodic_3_triangulation_3/include/CGAL/Periodic_3_triangulation_3.h

@@ -22,7 +22,6 @@
 #include <CGAL/basic.h>
 
 #include <CGAL/internal/Periodic_3_triangulation_iterators_3.h>
-#include <CGAL/result_of.h>
 #include <CGAL/Periodic_3_triangulation_ds_cell_base_3.h>
 #include <CGAL/Periodic_3_triangulation_ds_vertex_base_3.h>
 #include <CGAL/Periodic_3_triangulation_traits_3.h>

Periodic_4_hyperbolic_triangulation_2/include/CGAL/Periodic_4_hyperbolic_Delaunay_triangulation_2.h

@@ -24,7 +24,6 @@
 
 #include <CGAL/intersections.h>
 #include <CGAL/iterator.h>
-#include <CGAL/result_of.h>
 #include <CGAL/Timer.h>
 
 #include <iterator>

STL_Extension/include/CGAL/result_of.h

@@ -1,73 +0,0 @@
-// Copyright (c) 2013
-// Utrecht University (The Netherlands),
-// ETH Zurich (Switzerland),
-// INRIA Sophia-Antipolis (France),
-// Max-Planck-Institute Saarbruecken (Germany),
-// and Tel-Aviv University (Israel).  All rights reserved.
-//
-// This file is part of CGAL (www.cgal.org)
-//
-// $URL$
-// $Id$
-// SPDX-License-Identifier: LGPL-3.0-or-later OR LicenseRef-Commercial
-//
-//
-// Author(s)     : Sebastien Loriot <sebastien.loriot@cgal.org>
-
-
-#ifndef CGAL_RESULT_OF_H
-#define CGAL_RESULT_OF_H
-
-#include <CGAL/config.h>
-#include <CGAL/disable_warnings.h>
-
-#if CGAL_CXX20 || __cpp_lib_is_invocable>=201703L
-
-  // C++>=17
-
-#elif CGAL_CXX11
-
-  #include <type_traits>
-
-#else // C++<11
-
-  // Address the warning C4003: not enough actual parameters for macro 'BOOST_PP_SEQ_DETAIL_IS_NOT_EMPTY'
-  // result_of.hpp includes files from boost/preprocessor
-  // This concerns boost 1_65_1
-  #if defined(BOOST_MSVC)
-    #pragma warning(push)
-    #pragma warning(disable: 4003)
-  #endif
-    #include <boost/utility/result_of.hpp>
-  #if defined(BOOST_MSVC)
-    #pragma warning(pop)
-  #endif
-  #include <boost/version.hpp>
-
-#endif // end C++<11
-
-namespace CGAL {
-namespace cpp11 {
-
-#if CGAL_CXX20 || __cpp_lib_is_invocable>=201703L
-
-  template<typename Signature> class result_of;
-  template<typename F, typename... Args>
-  class result_of<F(Args...)> : public std::invoke_result<F, Args...> { };
-
-#elif CGAL_CXX11
-
-  using std::result_of;
-
-#else // C++<11
-
-  using boost::result_of;
-
-#endif // end C++<11
-
-} // end cpp11
-} // end CGAL
-
-#include <CGAL/enable_warnings.h>
-
-#endif // CGAL_RESULT_OF_H

Spatial_searching/include/CGAL/Manhattan_distance_iso_box_point.h

@@ -17,7 +17,6 @@
 #include <CGAL/license/Spatial_searching.h>
 
 
-#include <CGAL/result_of.h>
 #include <CGAL/Kd_tree_rectangle.h>
 #include <CGAL/internal/Get_dimension_tag.h>
 #include <vector>

Triangulation_3/include/CGAL/Regular_triangulation_3.h

@@ -38,7 +38,6 @@
 #include <CGAL/Cartesian_converter.h>
 #include <CGAL/Exact_predicates_exact_constructions_kernel.h>
 #include <CGAL/Kernel_traits.h>
-#include <CGAL/result_of.h>
 
 #ifndef CGAL_TRIANGULATION_3_DONT_INSERT_RANGE_OF_POINTS_WITH_INFO
 #include <CGAL/Spatial_sort_traits_adapter_3.h>