PLearn 0.1
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00001 // -*- C++ -*- 00002 00003 // ObjectConversions.h 00004 // 00005 // Copyright (C) 2005 Nicolas Chapados 00006 // 00007 // Redistribution and use in source and binary forms, with or without 00008 // modification, are permitted provided that the following conditions are met: 00009 // 00010 // 1. Redistributions of source code must retain the above copyright 00011 // notice, this list of conditions and the following disclaimer. 00012 // 00013 // 2. Redistributions in binary form must reproduce the above copyright 00014 // notice, this list of conditions and the following disclaimer in the 00015 // documentation and/or other materials provided with the distribution. 00016 // 00017 // 3. The name of the authors may not be used to endorse or promote 00018 // products derived from this software without specific prior written 00019 // permission. 00020 // 00021 // THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR 00022 // IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 00023 // OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN 00024 // NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 00025 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 00026 // TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 00027 // PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 00028 // LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 00029 // NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 00030 // SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 00031 // 00032 // This file is part of the PLearn library. For more information on the PLearn 00033 // library, go to the PLearn Web site at www.plearn.org 00034 00035 /* ******************************************************* 00036 * $Id: .pyskeleton_header 544 2003-09-01 00:05:31Z plearner $ 00037 ******************************************************* */ 00038 00039 // Authors: Nicolas Chapados 00040 00044 #ifndef ObjectConversions_INC 00045 #define ObjectConversions_INC 00046 00047 // From PLearn 00048 #include <plearn/base/Array.h> 00049 #include <plearn/base/TypeTraits.h> 00050 00051 // From Boost 00052 #include <boost/type_traits.hpp> 00053 00054 namespace PLearn { 00055 00056 class Object; 00057 00058 00059 //##### isConvertibleToObjectPtr ############################################ 00060 00065 template <class T> 00066 inline bool isConvertibleToObjectPtr(const T&) 00067 { 00068 return boost::is_convertible< typename boost::remove_cv<T>::type, 00069 const Object* >::value 00070 || boost::is_convertible< typename boost::remove_cv<T>::type*, 00071 const Object* >::value ; 00072 } 00073 00074 template <class T> 00075 inline bool isConvertibleToObjectPtr(const PP<T>& x) 00076 { 00077 return isConvertibleToObjectPtr((T*)0); 00078 } 00079 00080 template <class T> 00081 inline bool isConvertibleToObjectPtr(const Array<T>& x) 00082 { 00083 return isConvertibleToObjectPtr((T*)0); 00084 } 00085 00086 template <class T> 00087 inline bool isConvertibleToObjectPtr(const TVec<T>& x) 00088 { 00089 return isConvertibleToObjectPtr((T*)0); 00090 } 00091 00092 template <class T> 00093 inline bool isConvertibleToObjectPtr(const Array< PP<T> >& x) 00094 { 00095 return isConvertibleToObjectPtr((T*)0); 00096 } 00097 00098 template <class T> 00099 inline bool isConvertibleToObjectPtr(const TVec< PP<T> >& x) 00100 { 00101 return isConvertibleToObjectPtr((T*)0); 00102 } 00103 00104 00105 //##### indexableObjectSize ################################################# 00106 00121 template <class T> 00122 inline int indexableObjectSize(const T& x) 00123 { 00124 return 0; 00125 } 00126 00127 template <class T> 00128 inline int indexableObjectSize(const Array<T>& x) 00129 { 00130 return (x.size() > 0? x.size() : -1); 00131 } 00132 00133 template <class T> 00134 inline int indexableObjectSize(const TVec<T>& x) 00135 { 00136 return (x.size() > 0? x.size() : -1); 00137 } 00138 00139 00140 //##### toObjectPtr ######################################################### 00141 00142 // Hack to work with earlier versions of Boost 00143 typedef boost::is_convertible<int,int>::type boost_true_type; 00144 typedef boost::is_convertible<void,int>::type boost_false_type; 00145 00146 template <class T> 00147 Object* toObjectPtrImpl(const T&, const boost_false_type&) 00148 { 00149 PLERROR("Attempting to perform impossible conversion from type '%s' to Object*", 00150 TypeTraits<T>::name().c_str()); 00151 return 0; 00152 } 00153 00154 template <class T> 00155 Object* toObjectPtrImpl(const T& x, const boost_true_type&) 00156 { 00157 return const_cast<Object*>(static_cast<const Object*>(x)); 00158 } 00159 00160 00169 template<class T> 00170 inline Object* toObjectPtr(const T& x) 00171 { 00172 typedef typename boost::remove_cv<T>::type T_nocv; 00173 typedef typename boost::is_convertible<T_nocv, const Object*> T_isconv; 00174 typedef typename boost::is_convertible<T_nocv*, const Object*> pT_isconv; 00175 00176 if (pT_isconv::value) 00177 return toObjectPtrImpl(&x, pT_isconv()); 00178 else 00179 // May end up in the PLerror branch -- this is wanted 00180 return toObjectPtrImpl(x, T_isconv()); 00181 } 00182 00183 template<class T> 00184 inline Object* toObjectPtr(const PP<T>& x) 00185 { 00186 if (x.isNotNull()) 00187 return toObjectPtr(*static_cast<T *>(x)); 00188 else 00189 return 0; 00190 00191 } 00192 00193 00194 //##### toIndexedObjectPtr ################################################## 00195 00201 template<class T> 00202 Object* toIndexedObjectPtr(const Array<T> &x, int i) 00203 { 00204 return toObjectPtr(static_cast<T &>(x[i])); 00205 } 00206 00207 template<class T> 00208 Object* toIndexedObjectPtr(const TVec<T> &x, int i) 00209 { 00210 return toObjectPtr(static_cast<T &>(x[i])); 00211 } 00212 00213 template<class T> 00214 Object *toIndexedObjectPtr(const T&, int) // Never to be called stub 00215 { 00216 PLERROR("toIndexedObjectPtr() - Object is not indexable"); return 0; 00217 } 00218 00219 } // end of namespace PLearn 00220 00221 #endif 00222 00223 00224 /* 00225 Local Variables: 00226 mode:c++ 00227 c-basic-offset:4 00228 c-file-style:"stroustrup" 00229 c-file-offsets:((innamespace . 0)(inline-open . 0)) 00230 indent-tabs-mode:nil 00231 fill-column:79 00232 End: 00233 */ 00234 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=79 :