1 // Stack implementation -*- C++ -*- 2 3 // Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 4 // Free Software Foundation, Inc. 5 // 6 // This file is part of the GNU ISO C++ Library. This library is free 7 // software; you can redistribute it and/or modify it under the 8 // terms of the GNU General Public License as published by the 9 // Free Software Foundation; either version 3, or (at your option) 10 // any later version. 11 12 // This library is distributed in the hope that it will be useful, 13 // but WITHOUT ANY WARRANTY; without even the implied warranty of 14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 // GNU General Public License for more details. 16 17 // Under Section 7 of GPL version 3, you are granted additional 18 // permissions described in the GCC Runtime Library Exception, version 19 // 3.1, as published by the Free Software Foundation. 20 21 // You should have received a copy of the GNU General Public License and 22 // a copy of the GCC Runtime Library Exception along with this program; 23 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 24 // <http://www.gnu.org/licenses/>. 25 26 /* 27 * 28 * Copyright (c) 1994 29 * Hewlett-Packard Company 30 * 31 * Permission to use, copy, modify, distribute and sell this software 32 * and its documentation for any purpose is hereby granted without fee, 33 * provided that the above copyright notice appear in all copies and 34 * that both that copyright notice and this permission notice appear 35 * in supporting documentation. Hewlett-Packard Company makes no 36 * representations about the suitability of this software for any 37 * purpose. It is provided "as is" without express or implied warranty. 38 * 39 * 40 * Copyright (c) 1996,1997 41 * Silicon Graphics Computer Systems, Inc. 42 * 43 * Permission to use, copy, modify, distribute and sell this software 44 * and its documentation for any purpose is hereby granted without fee, 45 * provided that the above copyright notice appear in all copies and 46 * that both that copyright notice and this permission notice appear 47 * in supporting documentation. Silicon Graphics makes no 48 * representations about the suitability of this software for any 49 * purpose. It is provided "as is" without express or implied warranty. 50 */ 51 52 /** @file stl_stack.h 53 * This is an internal header file, included by other library headers. 54 * You should not attempt to use it directly. 55 */ 56 57 #ifndef _STL_STACK_H 58 #define _STL_STACK_H 1 59 60 #include <bits/concept_check.h> 61 #include <debug/debug.h> 62 63 _GLIBCXX_BEGIN_NAMESPACE(std) 64 65 /** 66 * @brief A standard container giving FILO behavior. 67 * 68 * @ingroup sequences 69 * 70 * Meets many of the requirements of a 71 * <a href="tables.html#65">container</a>, 72 * but does not define anything to do with iterators. Very few of the 73 * other standard container interfaces are defined. 74 * 75 * This is not a true container, but an @e adaptor. It holds 76 * another container, and provides a wrapper interface to that 77 * container. The wrapper is what enforces strict 78 * first-in-last-out %stack behavior. 79 * 80 * The second template parameter defines the type of the underlying 81 * sequence/container. It defaults to std::deque, but it can be 82 * any type that supports @c back, @c push_back, and @c pop_front, 83 * such as std::list, std::vector, or an appropriate user-defined 84 * type. 85 * 86 * Members not found in "normal" containers are @c container_type, 87 * which is a typedef for the second Sequence parameter, and @c 88 * push, @c pop, and @c top, which are standard %stack/FILO 89 * operations. 90 */ 91 template<typename _Tp, typename _Sequence = deque<_Tp> > 92 class stack 93 { 94 // concept requirements 95 typedef typename _Sequence::value_type _Sequence_value_type; 96 __glibcxx_class_requires(_Tp, _SGIAssignableConcept) 97 __glibcxx_class_requires(_Sequence, _BackInsertionSequenceConcept) 98 __glibcxx_class_requires2(_Tp, _Sequence_value_type, _SameTypeConcept) 99 100 template<typename _Tp1, typename _Seq1> 101 friend bool 102 operator==(const stack<_Tp1, _Seq1>&, const stack<_Tp1, _Seq1>&); 103 104 template<typename _Tp1, typename _Seq1> 105 friend bool 106 operator<(const stack<_Tp1, _Seq1>&, const stack<_Tp1, _Seq1>&); 107 108 public: 109 typedef typename _Sequence::value_type value_type; 110 typedef typename _Sequence::reference reference; 111 typedef typename _Sequence::const_reference const_reference; 112 typedef typename _Sequence::size_type size_type; 113 typedef _Sequence container_type; 114 115 protected: 116 // See queue::c for notes on this name. 117 _Sequence c; 118 119 public: 120 // XXX removed old def ctor, added def arg to this one to match 14882 121 /** 122 * @brief Default constructor creates no elements. 123 */ 124 #ifndef __GXX_EXPERIMENTAL_CXX0X__ 125 explicit 126 stack(const _Sequence& __c = _Sequence()) 127 : c(__c) { } 128 #else 129 explicit 130 stack(const _Sequence& __c) 131 : c(__c) { } 132 133 explicit 134 stack(_Sequence&& __c = _Sequence()) 135 : c(std::move(__c)) { } 136 #endif 137 138 /** 139 * Returns true if the %stack is empty. 140 */ 141 bool 142 empty() const 143 { return c.empty(); } 144 145 /** Returns the number of elements in the %stack. */ 146 size_type 147 size() const 148 { return c.size(); } 149 150 /** 151 * Returns a read/write reference to the data at the first 152 * element of the %stack. 153 */ 154 reference 155 top() 156 { 157 __glibcxx_requires_nonempty(); 158 return c.back(); 159 } 160 161 /** 162 * Returns a read-only (constant) reference to the data at the first 163 * element of the %stack. 164 */ 165 const_reference 166 top() const 167 { 168 __glibcxx_requires_nonempty(); 169 return c.back(); 170 } 171 172 /** 173 * @brief Add data to the top of the %stack. 174 * @param x Data to be added. 175 * 176 * This is a typical %stack operation. The function creates an 177 * element at the top of the %stack and assigns the given data 178 * to it. The time complexity of the operation depends on the 179 * underlying sequence. 180 */ 181 void 182 push(const value_type& __x) 183 { c.push_back(__x); } 184 185 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 186 void 187 push(value_type&& __x) 188 { c.push_back(std::move(__x)); } 189 190 template<typename... _Args> 191 void 192 emplace(_Args&&... __args) 193 { c.emplace_back(std::forward<_Args>(__args)...); } 194 #endif 195 196 /** 197 * @brief Removes first element. 198 * 199 * This is a typical %stack operation. It shrinks the %stack 200 * by one. The time complexity of the operation depends on the 201 * underlying sequence. 202 * 203 * Note that no data is returned, and if the first element's 204 * data is needed, it should be retrieved before pop() is 205 * called. 206 */ 207 void 208 pop() 209 { 210 __glibcxx_requires_nonempty(); 211 c.pop_back(); 212 } 213 214 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 215 void 216 swap(stack&& __s) 217 { c.swap(__s.c); } 218 #endif 219 }; 220 221 /** 222 * @brief Stack equality comparison. 223 * @param x A %stack. 224 * @param y A %stack of the same type as @a x. 225 * @return True iff the size and elements of the stacks are equal. 226 * 227 * This is an equivalence relation. Complexity and semantics 228 * depend on the underlying sequence type, but the expected rules 229 * are: this relation is linear in the size of the sequences, and 230 * stacks are considered equivalent if their sequences compare 231 * equal. 232 */ 233 template<typename _Tp, typename _Seq> 234 inline bool 235 operator==(const stack<_Tp, _Seq>& __x, const stack<_Tp, _Seq>& __y) 236 { return __x.c == __y.c; } 237 238 /** 239 * @brief Stack ordering relation. 240 * @param x A %stack. 241 * @param y A %stack of the same type as @a x. 242 * @return True iff @a x is lexicographically less than @a y. 243 * 244 * This is an total ordering relation. Complexity and semantics 245 * depend on the underlying sequence type, but the expected rules 246 * are: this relation is linear in the size of the sequences, the 247 * elements must be comparable with @c <, and 248 * std::lexicographical_compare() is usually used to make the 249 * determination. 250 */ 251 template<typename _Tp, typename _Seq> 252 inline bool 253 operator<(const stack<_Tp, _Seq>& __x, const stack<_Tp, _Seq>& __y) 254 { return __x.c < __y.c; } 255 256 /// Based on operator== 257 template<typename _Tp, typename _Seq> 258 inline bool 259 operator!=(const stack<_Tp, _Seq>& __x, const stack<_Tp, _Seq>& __y) 260 { return !(__x == __y); } 261 262 /// Based on operator< 263 template<typename _Tp, typename _Seq> 264 inline bool 265 operator>(const stack<_Tp, _Seq>& __x, const stack<_Tp, _Seq>& __y) 266 { return __y < __x; } 267 268 /// Based on operator< 269 template<typename _Tp, typename _Seq> 270 inline bool 271 operator<=(const stack<_Tp, _Seq>& __x, const stack<_Tp, _Seq>& __y) 272 { return !(__y < __x); } 273 274 /// Based on operator< 275 template<typename _Tp, typename _Seq> 276 inline bool 277 operator>=(const stack<_Tp, _Seq>& __x, const stack<_Tp, _Seq>& __y) 278 { return !(__x < __y); } 279 280 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 281 template<typename _Tp, typename _Seq> 282 inline void 283 swap(stack<_Tp, _Seq>& __x, stack<_Tp, _Seq>& __y) 284 { __x.swap(__y); } 285 286 template<typename _Tp, typename _Seq> 287 inline void 288 swap(stack<_Tp, _Seq>&& __x, stack<_Tp, _Seq>& __y) 289 { __x.swap(__y); } 290 291 template<typename _Tp, typename _Seq> 292 inline void 293 swap(stack<_Tp, _Seq>& __x, stack<_Tp, _Seq>&& __y) 294 { __x.swap(__y); } 295 #endif 296 297 _GLIBCXX_END_NAMESPACE 298 299 #endif /* _STL_STACK_H */ 300
