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_METAL_IF_HH 00027 # define MLN_METAL_IF_HH 00028 00034 # include <mln/metal/bool.hh> 00035 00036 # define mlc_if(Cond, Then, Else) typename mln::metal::if_< Cond, Then, Else >::ret 00037 00038 00039 00040 namespace mln 00041 { 00042 00043 namespace metal 00044 { 00045 00046 namespace internal 00047 { 00048 00049 template <bool cond, typename Then, typename Else> 00050 struct helper_if_; 00051 00052 template <typename Then, typename Else> 00053 struct helper_if_< true, Then, Else > 00054 { 00055 typedef Then ret; 00056 }; 00057 00058 template <typename Then, typename Else> 00059 struct helper_if_< false, Then, Else > 00060 { 00061 typedef Else ret; 00062 }; 00063 00064 } // end of namespace mln::metal::internal 00065 00066 00071 template <typename Cond, typename Then, typename Else> 00072 struct if_ : internal::helper_if_< Cond::value, Then, Else > 00073 { 00074 // ret is inherited. 00075 }; 00076 00077 00078 } // end of namespace mln::metal 00079 00080 } // end of namespace mln 00081 00082 00083 #endif // ! MLN_METAL_IF_HH
1.7.1