00001 //============================================================================= 00002 // 00003 // OpenMesh 00004 // Copyright (C) 2001-2005 by Computer Graphics Group, RWTH Aachen 00005 // www.openmesh.org 00006 // 00007 //----------------------------------------------------------------------------- 00008 // 00009 // License 00010 // 00011 // This library is free software; you can redistribute it and/or modify it 00012 // under the terms of the GNU Library General Public License as published 00013 // by the Free Software Foundation, version 2. 00014 // 00015 // This library is distributed in the hope that it will be useful, but 00016 // WITHOUT ANY WARRANTY; without even the implied warranty of 00017 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 00018 // Library General Public License for more details. 00019 // 00020 // You should have received a copy of the GNU Library General Public 00021 // License along with this library; if not, write to the Free Software 00022 // Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 00023 // 00024 //----------------------------------------------------------------------------- 00025 // 00026 // $Revision: 1.1.1.1 $ 00027 // $Date: 2004/09/06 12:35:33 $ 00028 // 00029 //============================================================================= 00030 00031 00032 //============================================================================= 00033 // 00034 // Utils for generic/generative programming 00035 // 00036 //============================================================================= 00037 00038 #ifndef OPENMESH_GENPROG_HH 00039 #define OPENMESH_GENPROG_HH 00040 00041 00042 //== INCLUDES ================================================================= 00043 00044 #include <OpenMesh/Core/System/config.hh> 00045 00046 00047 //== NAMESPACES =============================================================== 00048 00049 namespace OpenMesh { 00050 namespace GenProg { 00051 #ifndef DOXY_IGNORE_THIS 00052 00053 //== IMPLEMENTATION =========================================================== 00054 00055 00057 template <bool b> class Bool2Type { enum { my_bool = b }; }; 00058 00060 template <int i> class Int2Type { enum { my_int = i }; }; 00061 00063 typedef Bool2Type<true> True; 00064 00066 typedef Bool2Type<false> False; 00067 00068 00069 //----------------------------------------------------------------------------- 00070 00071 00072 00073 //--- Template "if" w/ partial specialization --------------------------------- 00074 #if OM_PARTIAL_SPECIALIZATION 00075 00076 00077 template <bool condition, class Then, class Else> 00078 struct IF { typedef Then Result; }; 00079 00085 template <class Then, class Else> 00086 struct IF<false, Then, Else> { typedef Else Result; }; 00087 00088 00089 00090 00091 00092 //--- Template "if" w/o partial specialization -------------------------------- 00093 #else 00094 00095 00096 struct SelectThen 00097 { 00098 template <class Then, class Else> struct Select { 00099 typedef Then Result; 00100 }; 00101 }; 00102 00103 struct SelectElse 00104 { 00105 template <class Then, class Else> struct Select { 00106 typedef Else Result; 00107 }; 00108 }; 00109 00110 template <bool condition> struct ChooseSelector { 00111 typedef SelectThen Result; 00112 }; 00113 00114 template <> struct ChooseSelector<false> { 00115 typedef SelectElse Result; 00116 }; 00117 00118 00125 template <bool condition, class Then, class Else> 00126 class IF 00127 { 00128 typedef typename ChooseSelector<condition>::Result Selector; 00129 public: 00130 typedef typename Selector::template Select<Then, Else>::Result Result; 00131 }; 00132 00133 #endif 00134 00135 //============================================================================= 00136 #endif 00137 } // namespace GenProg 00138 } // namespace OpenMesh 00139 //============================================================================= 00140 #endif // OPENMESH_GENPROG_HH defined 00141 //=============================================================================