00001 // Copyright (C) 2007, 2008, 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_IS_HH 00027 # define MLN_METAL_IS_HH 00028 00032 00033 # include <mln/metal/is_a.hh> 00034 00035 00036 # define mlc_is(T, U) mln::metal::is< T, U > 00037 00038 00039 00040 namespace mln 00041 { 00042 00043 namespace metal 00044 { 00045 00046 namespace internal 00047 { 00048 00049 template <typename T, typename U> 00050 struct helper_is_ 00051 { 00052 static yes_ selector(U*const); 00053 static no_ selector(...); 00054 }; 00055 00056 } // end of namespace mln::metal::internal 00057 00058 00059 00062 // 00063 template <typename T, typename U> 00064 struct is : bool_<( sizeof(internal::helper_is_<T, U>::selector(internal::make_<T>::ptr())) 00065 == 00066 sizeof(internal::yes_) )> 00067 { 00068 }; 00069 00070 template <typename T, typename U> 00071 struct is< const T, const U > : is<T, U>::eval 00072 {}; 00073 00074 template <typename T, typename U> 00075 struct is< T*, U* > : is<T, U>::eval 00076 {}; 00077 00078 template <typename T, typename U> 00079 struct is< T&, U& > : is<T, U>::eval 00080 {}; 00081 00082 template <typename T, typename U> 00083 struct is< T**, U** > : false_ 00084 {}; 00085 00086 } // end of namespace mln::metal 00087 00088 } // end of namespace mln 00089 00090 00091 #endif // ! MLN_METAL_IS_HH