1 // Stack implementation -*- C++ -*- 2 3 // Copyright (C) 2001-2014 Free Software Foundation, Inc. 4 // 5 // This file is part of the GNU ISO C++ Library. This library is free 6 // software; you can redistribute it and/or modify it under the 7 // terms of the GNU General Public License as published by the 8 // Free Software Foundation; either version 3, or (at your option) 9 // any later version. 10 11 // This library is distributed in the hope that it will be useful, 12 // but WITHOUT ANY WARRANTY; without even the implied warranty of 13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 // GNU General Public License for more details. 15 16 // Under Section 7 of GPL version 3, you are granted additional 17 // permissions described in the GCC Runtime Library Exception, version 18 // 3.1, as published by the Free Software Foundation. 19 20 // You should have received a copy of the GNU General Public License and 21 // a copy of the GCC Runtime Library Exception along with this program; 22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 23 // <http://www.gnu.org/licenses/>. 24 25 /* 26 * 27 * Copyright (c) 1994 28 * Hewlett-Packard Company 29 * 30 * Permission to use, copy, modify, distribute and sell this software 31 * and its documentation for any purpose is hereby granted without fee, 32 * provided that the above copyright notice appear in all copies and 33 * that both that copyright notice and this permission notice appear 34 * in supporting documentation. Hewlett-Packard Company makes no 35 * representations about the suitability of this software for any 36 * purpose. It is provided "as is" without express or implied warranty. 37 * 38 * 39 * Copyright (c) 1996,1997 40 * Silicon Graphics Computer Systems, Inc. 41 * 42 * Permission to use, copy, modify, distribute and sell this software 43 * and its documentation for any purpose is hereby granted without fee, 44 * provided that the above copyright notice appear in all copies and 45 * that both that copyright notice and this permission notice appear 46 * in supporting documentation. Silicon Graphics makes no 47 * representations about the suitability of this software for any 48 * purpose. It is provided "as is" without express or implied warranty. 49 */ 50 51 /** @file bits/stl_stack.h 52 * This is an internal header file, included by other library headers. 53 * Do not attempt to use it directly. @headername{stack} 54 */ 55 56 #ifndef _STL_STACK_H 57 #define _STL_STACK_H 1 58 59 #include <bits/concept_check.h> 60 #include <debug/debug.h> 61 #if __cplusplus >= 201103L 62 # include <bits/uses_allocator.h> 63 #endif 64 65 namespace std _GLIBCXX_VISIBILITY(default) 66 { 67 _GLIBCXX_BEGIN_NAMESPACE_VERSION 68 69 /** 70 * @brief A standard container giving FILO behavior. 71 * 72 * @ingroup sequences 73 * 74 * @tparam _Tp Type of element. 75 * @tparam _Sequence Type of underlying sequence, defaults to deque<_Tp>. 76 * 77 * Meets many of the requirements of a 78 * <a href="tables.html#65">container</a>, 79 * but does not define anything to do with iterators. Very few of the 80 * other standard container interfaces are defined. 81 * 82 * This is not a true container, but an @e adaptor. It holds 83 * another container, and provides a wrapper interface to that 84 * container. The wrapper is what enforces strict 85 * first-in-last-out %stack behavior. 86 * 87 * The second template parameter defines the type of the underlying 88 * sequence/container. It defaults to std::deque, but it can be 89 * any type that supports @c back, @c push_back, and @c pop_front, 90 * such as std::list, std::vector, or an appropriate user-defined 91 * type. 92 * 93 * Members not found in @a normal containers are @c container_type, 94 * which is a typedef for the second Sequence parameter, and @c 95 * push, @c pop, and @c top, which are standard %stack/FILO 96 * operations. 97 */ 98 template<typename _Tp, typename _Sequence = deque<_Tp> > 99 class stack 100 { 101 // concept requirements 102 typedef typename _Sequence::value_type _Sequence_value_type; 103 __glibcxx_class_requires(_Tp, _SGIAssignableConcept) 104 __glibcxx_class_requires(_Sequence, _BackInsertionSequenceConcept) 105 __glibcxx_class_requires2(_Tp, _Sequence_value_type, _SameTypeConcept) 106 107 template<typename _Tp1, typename _Seq1> 108 friend bool 109 operator==(const stack<_Tp1, _Seq1>&, const stack<_Tp1, _Seq1>&); 110 111 template<typename _Tp1, typename _Seq1> 112 friend bool 113 operator<(const stack<_Tp1, _Seq1>&, const stack<_Tp1, _Seq1>&); 114 115 public: 116 typedef typename _Sequence::value_type value_type; 117 typedef typename _Sequence::reference reference; 118 typedef typename _Sequence::const_reference const_reference; 119 typedef typename _Sequence::size_type size_type; 120 typedef _Sequence container_type; 121 122 protected: 123 // See queue::c for notes on this name. 124 _Sequence c; 125 126 public: 127 // XXX removed old def ctor, added def arg to this one to match 14882 128 /** 129 * @brief Default constructor creates no elements. 130 */ 131 #if __cplusplus < 201103L 132 explicit 133 stack(const _Sequence& __c = _Sequence()) 134 : c(__c) { } 135 #else 136 explicit 137 stack(const _Sequence& __c) 138 : c(__c) { } 139 140 explicit 141 stack(_Sequence&& __c = _Sequence()) 142 : c(std::move(__c)) { } 143 #endif 144 145 /** 146 * Returns true if the %stack is empty. 147 */ 148 bool 149 empty() const 150 { return c.empty(); } 151 152 /** Returns the number of elements in the %stack. */ 153 size_type 154 size() const 155 { return c.size(); } 156 157 /** 158 * Returns a read/write reference to the data at the first 159 * element of the %stack. 160 */ 161 reference 162 top() 163 { 164 __glibcxx_requires_nonempty(); 165 return c.back(); 166 } 167 168 /** 169 * Returns a read-only (constant) reference to the data at the first 170 * element of the %stack. 171 */ 172 const_reference 173 top() const 174 { 175 __glibcxx_requires_nonempty(); 176 return c.back(); 177 } 178 179 /** 180 * @brief Add data to the top of the %stack. 181 * @param __x Data to be added. 182 * 183 * This is a typical %stack operation. The function creates an 184 * element at the top of the %stack and assigns the given data 185 * to it. The time complexity of the operation depends on the 186 * underlying sequence. 187 */ 188 void 189 push(const value_type& __x) 190 { c.push_back(__x); } 191 192 #if __cplusplus >= 201103L 193 void 194 push(value_type&& __x) 195 { c.push_back(std::move(__x)); } 196 197 template<typename... _Args> 198 void 199 emplace(_Args&&... __args) 200 { c.emplace_back(std::forward<_Args>(__args)...); } 201 #endif 202 203 /** 204 * @brief Removes first element. 205 * 206 * This is a typical %stack operation. It shrinks the %stack 207 * by one. The time complexity of the operation depends on the 208 * underlying sequence. 209 * 210 * Note that no data is returned, and if the first element's 211 * data is needed, it should be retrieved before pop() is 212 * called. 213 */ 214 void 215 pop() 216 { 217 __glibcxx_requires_nonempty(); 218 c.pop_back(); 219 } 220 221 #if __cplusplus >= 201103L 222 void 223 swap(stack& __s) 224 noexcept(noexcept(swap(c, __s.c))) 225 { 226 using std::swap; 227 swap(c, __s.c); 228 } 229 #endif 230 }; 231 232 /** 233 * @brief Stack equality comparison. 234 * @param __x A %stack. 235 * @param __y A %stack of the same type as @a __x. 236 * @return True iff the size and elements of the stacks are equal. 237 * 238 * This is an equivalence relation. Complexity and semantics 239 * depend on the underlying sequence type, but the expected rules 240 * are: this relation is linear in the size of the sequences, and 241 * stacks are considered equivalent if their sequences compare 242 * equal. 243 */ 244 template<typename _Tp, typename _Seq> 245 inline bool 246 operator==(const stack<_Tp, _Seq>& __x, const stack<_Tp, _Seq>& __y) 247 { return __x.c == __y.c; } 248 249 /** 250 * @brief Stack ordering relation. 251 * @param __x A %stack. 252 * @param __y A %stack of the same type as @a x. 253 * @return True iff @a x is lexicographically less than @a __y. 254 * 255 * This is an total ordering relation. Complexity and semantics 256 * depend on the underlying sequence type, but the expected rules 257 * are: this relation is linear in the size of the sequences, the 258 * elements must be comparable with @c <, and 259 * std::lexicographical_compare() is usually used to make the 260 * determination. 261 */ 262 template<typename _Tp, typename _Seq> 263 inline bool 264 operator<(const stack<_Tp, _Seq>& __x, const stack<_Tp, _Seq>& __y) 265 { return __x.c < __y.c; } 266 267 /// Based on operator== 268 template<typename _Tp, typename _Seq> 269 inline bool 270 operator!=(const stack<_Tp, _Seq>& __x, const stack<_Tp, _Seq>& __y) 271 { return !(__x == __y); } 272 273 /// Based on operator< 274 template<typename _Tp, typename _Seq> 275 inline bool 276 operator>(const stack<_Tp, _Seq>& __x, const stack<_Tp, _Seq>& __y) 277 { return __y < __x; } 278 279 /// Based on operator< 280 template<typename _Tp, typename _Seq> 281 inline bool 282 operator<=(const stack<_Tp, _Seq>& __x, const stack<_Tp, _Seq>& __y) 283 { return !(__y < __x); } 284 285 /// Based on operator< 286 template<typename _Tp, typename _Seq> 287 inline bool 288 operator>=(const stack<_Tp, _Seq>& __x, const stack<_Tp, _Seq>& __y) 289 { return !(__x < __y); } 290 291 #if __cplusplus >= 201103L 292 template<typename _Tp, typename _Seq> 293 inline void 294 swap(stack<_Tp, _Seq>& __x, stack<_Tp, _Seq>& __y) 295 noexcept(noexcept(__x.swap(__y))) 296 { __x.swap(__y); } 297 298 template<typename _Tp, typename _Seq, typename _Alloc> 299 struct uses_allocator<stack<_Tp, _Seq>, _Alloc> 300 : public uses_allocator<_Seq, _Alloc>::type { }; 301 #endif 302 303 _GLIBCXX_END_NAMESPACE_VERSION 304 } // namespace 305 306 #endif /* _STL_STACK_H */ 307
