00001 // Copyright (C) 2007, 2009 EPITA Research and Development Laboratory (LRDE) 00002 // 00003 // This file is part of Olena. 00004 // 00005 // Olena is free software: you can redistribute it and/or modify it under 00006 // the terms of the GNU General Public License as published by the Free 00007 // Software Foundation, version 2 of the License. 00008 // 00009 // Olena is distributed in the hope that it will be useful, 00010 // but WITHOUT ANY WARRANTY; without even the implied warranty of 00011 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 00012 // General Public License for more details. 00013 // 00014 // You should have received a copy of the GNU General Public License 00015 // along with Olena. If not, see <http://www.gnu.org/licenses/>. 00016 // 00017 // As a special exception, you may use this file as part of a free 00018 // software project without restriction. Specifically, if other files 00019 // instantiate templates or use macros or inline functions from this 00020 // file, or you compile this file and link it with other files to produce 00021 // an executable, this file does not by itself cause the resulting 00022 // executable to be covered by the GNU General Public License. This 00023 // exception does not however invalidate any other reasons why the 00024 // executable file might be covered by the GNU General Public License. 00025 00026 #ifndef MLN_CORE_CONCEPT_LITERAL_HH 00027 # define MLN_CORE_CONCEPT_LITERAL_HH 00028 00033 # include <mln/core/concept/object.hh> 00034 00035 00036 namespace mln 00037 { 00038 00039 // Fwd decl. 00040 template <typename E> struct Literal; 00041 00042 // Literal category flag type. 00043 template <> 00044 struct Literal<void> 00045 { 00046 typedef Object<void> super; 00047 }; 00048 00049 00055 template <typename E> 00056 struct Literal : public Object<E> 00057 { 00058 typedef Literal<void> category; 00059 00060 static const E& the(); 00061 00062 protected: 00063 Literal(); 00064 }; 00065 00066 00067 00068 # ifndef MLN_INCLUDE_ONLY 00069 00070 template <typename E> 00071 inline 00072 Literal<E>::Literal() 00073 { 00074 } 00075 00076 template <typename E> 00077 inline 00078 const E& 00079 Literal<E>::the() 00080 { 00081 static E the_; 00082 return the_; 00083 } 00084 00085 # endif // ! MLN_INCLUDE_ONLY 00086 00087 00088 } // end of namespace mln 00089 00090 00091 #endif // ! MLN_CORE_CONCEPT_LITERAL_HH
1.7.1