libstdc++
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00001 // Move, forward and identity for C++0x + swap -*- C++ -*- 00002 00003 // Copyright (C) 2007, 2008, 2009, 2010 Free Software Foundation, Inc. 00004 // 00005 // This file is part of the GNU ISO C++ Library. This library is free 00006 // software; you can redistribute it and/or modify it under the 00007 // terms of the GNU General Public License as published by the 00008 // Free Software Foundation; either version 3, or (at your option) 00009 // any later version. 00010 00011 // This library is distributed in the hope that it will be useful, 00012 // but WITHOUT ANY WARRANTY; without even the implied warranty of 00013 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 00014 // GNU General Public License for more details. 00015 00016 // Under Section 7 of GPL version 3, you are granted additional 00017 // permissions described in the GCC Runtime Library Exception, version 00018 // 3.1, as published by the Free Software Foundation. 00019 00020 // You should have received a copy of the GNU General Public License and 00021 // a copy of the GCC Runtime Library Exception along with this program; 00022 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 00023 // <http://www.gnu.org/licenses/>. 00024 00025 /** @file bits/move.h 00026 * This is an internal header file, included by other library headers. 00027 * Do not attempt to use it directly. @headername{utility} 00028 */ 00029 00030 #ifndef _MOVE_H 00031 #define _MOVE_H 1 00032 00033 #include <bits/c++config.h> 00034 #include <bits/concept_check.h> 00035 00036 namespace std _GLIBCXX_VISIBILITY(default) 00037 { 00038 _GLIBCXX_BEGIN_NAMESPACE_VERSION 00039 00040 // Used, in C++03 mode too, by allocators, etc. 00041 template<typename _Tp> 00042 inline _Tp* 00043 __addressof(_Tp& __r) 00044 { 00045 return reinterpret_cast<_Tp*> 00046 (&const_cast<char&>(reinterpret_cast<const volatile char&>(__r))); 00047 } 00048 00049 _GLIBCXX_END_NAMESPACE_VERSION 00050 } // namespace 00051 00052 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 00053 #include <type_traits> // Brings in std::declval too. 00054 00055 namespace std _GLIBCXX_VISIBILITY(default) 00056 { 00057 _GLIBCXX_BEGIN_NAMESPACE_VERSION 00058 00059 /// forward (as per N3143) 00060 template<typename _Tp> 00061 inline _Tp&& 00062 forward(typename std::remove_reference<_Tp>::type& __t) 00063 { return static_cast<_Tp&&>(__t); } 00064 00065 template<typename _Tp> 00066 inline _Tp&& 00067 forward(typename std::remove_reference<_Tp>::type&& __t) 00068 { 00069 static_assert(!std::is_lvalue_reference<_Tp>::value, "template argument" 00070 " substituting _Tp is an lvalue reference type"); 00071 return static_cast<_Tp&&>(__t); 00072 } 00073 00074 /** 00075 * @brief Move a value. 00076 * @ingroup mutating_algorithms 00077 * @param __t A thing of arbitrary type. 00078 * @return Same, moved. 00079 */ 00080 template<typename _Tp> 00081 inline typename std::remove_reference<_Tp>::type&& 00082 move(_Tp&& __t) 00083 { return static_cast<typename std::remove_reference<_Tp>::type&&>(__t); } 00084 00085 /// declval, from type_traits. 00086 00087 /** 00088 * @brief Returns the actual address of the object or function 00089 * referenced by r, even in the presence of an overloaded 00090 * operator&. 00091 * @param __r Reference to an object or function. 00092 * @return The actual address. 00093 */ 00094 template<typename _Tp> 00095 inline _Tp* 00096 addressof(_Tp& __r) 00097 { return std::__addressof(__r); } 00098 00099 _GLIBCXX_END_NAMESPACE_VERSION 00100 } // namespace 00101 00102 #define _GLIBCXX_MOVE(__val) std::move(__val) 00103 #define _GLIBCXX_FORWARD(_Tp, __val) std::forward<_Tp>(__val) 00104 #else 00105 #define _GLIBCXX_MOVE(__val) (__val) 00106 #define _GLIBCXX_FORWARD(_Tp, __val) (__val) 00107 #endif 00108 00109 namespace std _GLIBCXX_VISIBILITY(default) 00110 { 00111 _GLIBCXX_BEGIN_NAMESPACE_VERSION 00112 00113 /** 00114 * @brief Swaps two values. 00115 * @ingroup mutating_algorithms 00116 * @param __a A thing of arbitrary type. 00117 * @param __b Another thing of arbitrary type. 00118 * @return Nothing. 00119 */ 00120 template<typename _Tp> 00121 inline void 00122 swap(_Tp& __a, _Tp& __b) 00123 { 00124 // concept requirements 00125 __glibcxx_function_requires(_SGIAssignableConcept<_Tp>) 00126 00127 _Tp __tmp = _GLIBCXX_MOVE(__a); 00128 __a = _GLIBCXX_MOVE(__b); 00129 __b = _GLIBCXX_MOVE(__tmp); 00130 } 00131 00132 // _GLIBCXX_RESOLVE_LIB_DEFECTS 00133 // DR 809. std::swap should be overloaded for array types. 00134 template<typename _Tp, size_t _Nm> 00135 inline void 00136 swap(_Tp (&__a)[_Nm], _Tp (&__b)[_Nm]) 00137 { 00138 for (size_t __n = 0; __n < _Nm; ++__n) 00139 swap(__a[__n], __b[__n]); 00140 } 00141 00142 _GLIBCXX_END_NAMESPACE_VERSION 00143 } // namespace 00144 00145 #endif /* _MOVE_H */