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Howard Hinnantc51e1022010-05-11 19:42:16 +00001// -*- C++ -*-
Louis Dionne9bd93882021-11-17 16:25:01 -05002//===----------------------------------------------------------------------===//
Howard Hinnantc51e1022010-05-11 19:42:16 +00003//
Chandler Carruthd2012102019-01-19 10:56:40 +00004// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5// See https://llvm.org/LICENSE.txt for license information.
6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
Howard Hinnantc51e1022010-05-11 19:42:16 +00007//
8//===----------------------------------------------------------------------===//
9
10#ifndef _LIBCPP_STACK
11#define _LIBCPP_STACK
12
13/*
14 stack synopsis
15
16namespace std
17{
18
19template <class T, class Container = deque<T>>
20class stack
21{
22public:
23 typedef Container container_type;
24 typedef typename container_type::value_type value_type;
25 typedef typename container_type::reference reference;
26 typedef typename container_type::const_reference const_reference;
27 typedef typename container_type::size_type size_type;
28
29protected:
30 container_type c;
31
32public:
Howard Hinnante0da4a12011-06-04 22:09:19 +000033 stack() = default;
34 ~stack() = default;
35
36 stack(const stack& q) = default;
37 stack(stack&& q) = default;
38
39 stack& operator=(const stack& q) = default;
40 stack& operator=(stack&& q) = default;
41
Howard Hinnantc51e1022010-05-11 19:42:16 +000042 explicit stack(const container_type& c);
43 explicit stack(container_type&& c);
Nikolas Klauserf0b3d872022-01-06 12:36:07 +010044 template <class InputIterator> stack(InputIterator first, InputIterator last); // since C++23
Howard Hinnantc51e1022010-05-11 19:42:16 +000045 template <class Alloc> explicit stack(const Alloc& a);
46 template <class Alloc> stack(const container_type& c, const Alloc& a);
47 template <class Alloc> stack(container_type&& c, const Alloc& a);
Howard Hinnante0da4a12011-06-04 22:09:19 +000048 template <class Alloc> stack(const stack& c, const Alloc& a);
Howard Hinnantc51e1022010-05-11 19:42:16 +000049 template <class Alloc> stack(stack&& c, const Alloc& a);
Nikolas Klauserf0b3d872022-01-06 12:36:07 +010050 template<class InputIterator, class Alloc>
51 stack(InputIterator first, InputIterator last, const Alloc&); // since C++23
Howard Hinnantc51e1022010-05-11 19:42:16 +000052
53 bool empty() const;
54 size_type size() const;
55 reference top();
56 const_reference top() const;
57
58 void push(const value_type& x);
59 void push(value_type&& x);
Marshall Clowea52cc42017-01-24 23:09:12 +000060 template <class... Args> reference emplace(Args&&... args); // reference in C++17
Howard Hinnantc51e1022010-05-11 19:42:16 +000061 void pop();
62
Eric Fiselier6bfed252016-04-21 23:38:59 +000063 void swap(stack& c) noexcept(is_nothrow_swappable_v<Container>)
Howard Hinnantc51e1022010-05-11 19:42:16 +000064};
65
Marshall Clow592d9952018-05-22 01:57:53 +000066template<class Container>
67 stack(Container) -> stack<typename Container::value_type, Container>; // C++17
Louis Dionne173f29e2019-05-29 16:01:36 +000068
Nikolas Klauserf0b3d872022-01-06 12:36:07 +010069template<class InputIterator>
70 stack(InputIterator, InputIterator) -> stack<iter-value-type<InputIterator>>; // since C++23
71
Louis Dionne173f29e2019-05-29 16:01:36 +000072template<class Container, class Allocator>
Marshall Clow592d9952018-05-22 01:57:53 +000073 stack(Container, Allocator) -> stack<typename Container::value_type, Container>; // C++17
74
Nikolas Klauserf0b3d872022-01-06 12:36:07 +010075template<class InputIterator, class Allocator>
76 stack(InputIterator, InputIterator, Allocator)
77 -> stack<iter-value-type<InputIterator>,
78 deque<iter-value-type<InputIterator>, Allocator>>; // since C++23
79
Howard Hinnantc51e1022010-05-11 19:42:16 +000080template <class T, class Container>
81 bool operator==(const stack<T, Container>& x, const stack<T, Container>& y);
82template <class T, class Container>
83 bool operator< (const stack<T, Container>& x, const stack<T, Container>& y);
84template <class T, class Container>
85 bool operator!=(const stack<T, Container>& x, const stack<T, Container>& y);
86template <class T, class Container>
87 bool operator> (const stack<T, Container>& x, const stack<T, Container>& y);
88template <class T, class Container>
89 bool operator>=(const stack<T, Container>& x, const stack<T, Container>& y);
90template <class T, class Container>
91 bool operator<=(const stack<T, Container>& x, const stack<T, Container>& y);
92
93template <class T, class Container>
Howard Hinnante0da4a12011-06-04 22:09:19 +000094 void swap(stack<T, Container>& x, stack<T, Container>& y)
95 noexcept(noexcept(x.swap(y)));
Howard Hinnantc51e1022010-05-11 19:42:16 +000096
97} // std
98
99*/
100
Louis Dionneb4fce352022-03-25 12:55:36 -0400101#include <__assert> // all public C++ headers provide the assertion handler
Howard Hinnantc51e1022010-05-11 19:42:16 +0000102#include <__config>
Nikolas Klauserf0b3d872022-01-06 12:36:07 +0100103#include <__iterator/iterator_traits.h>
Christopher Di Bella55d7a822021-07-01 09:25:35 -0400104#include <__memory/uses_allocator.h>
Christopher Di Bella41f26e82021-06-05 02:47:47 +0000105#include <__utility/forward.h>
Howard Hinnantc51e1022010-05-11 19:42:16 +0000106#include <deque>
Nikolas Klauserf0b3d872022-01-06 12:36:07 +0100107#include <type_traits>
Mark de Weverce8f12c2021-12-22 18:14:14 +0100108#include <version>
Howard Hinnantc51e1022010-05-11 19:42:16 +0000109
Nikolas Klausera0e0edb2022-06-16 22:43:46 +0200110// standard-mandated includes
Nikolas Klauser71619e72022-09-22 18:05:08 +0200111
112// [stack.syn]
Nikolas Klausera0e0edb2022-06-16 22:43:46 +0200113#include <compare>
114#include <initializer_list>
115
Howard Hinnantaaaa52b2011-10-17 20:05:10 +0000116#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
Arthur O'Dwyer6eeaa002022-02-01 20:16:40 -0500117# pragma GCC system_header
Howard Hinnantaaaa52b2011-10-17 20:05:10 +0000118#endif
Howard Hinnantc51e1022010-05-11 19:42:16 +0000119
120_LIBCPP_BEGIN_NAMESPACE_STD
121
Eric Fiselierb5eb1bf2017-01-04 23:56:00 +0000122template <class _Tp, class _Container = deque<_Tp> > class _LIBCPP_TEMPLATE_VIS stack;
Howard Hinnantc51e1022010-05-11 19:42:16 +0000123
124template <class _Tp, class _Container>
Howard Hinnanta54386e2012-09-14 00:39:16 +0000125_LIBCPP_INLINE_VISIBILITY
Howard Hinnantc51e1022010-05-11 19:42:16 +0000126bool
127operator==(const stack<_Tp, _Container>& __x, const stack<_Tp, _Container>& __y);
128
129template <class _Tp, class _Container>
Howard Hinnanta54386e2012-09-14 00:39:16 +0000130_LIBCPP_INLINE_VISIBILITY
Howard Hinnantc51e1022010-05-11 19:42:16 +0000131bool
132operator< (const stack<_Tp, _Container>& __x, const stack<_Tp, _Container>& __y);
133
Marshall Clow9e1b8452015-02-18 17:51:56 +0000134template <class _Tp, class _Container /*= deque<_Tp>*/>
Eric Fiselierb5eb1bf2017-01-04 23:56:00 +0000135class _LIBCPP_TEMPLATE_VIS stack
Howard Hinnantc51e1022010-05-11 19:42:16 +0000136{
137public:
138 typedef _Container container_type;
139 typedef typename container_type::value_type value_type;
140 typedef typename container_type::reference reference;
141 typedef typename container_type::const_reference const_reference;
142 typedef typename container_type::size_type size_type;
Marshall Clowb8825f02016-03-14 17:58:11 +0000143 static_assert((is_same<_Tp, value_type>::value), "" );
Louis Dionne173f29e2019-05-29 16:01:36 +0000144
Howard Hinnantc51e1022010-05-11 19:42:16 +0000145protected:
146 container_type c;
147
148public:
Howard Hinnant186dca82010-09-23 17:31:07 +0000149 _LIBCPP_INLINE_VISIBILITY
Howard Hinnante0da4a12011-06-04 22:09:19 +0000150 stack()
151 _NOEXCEPT_(is_nothrow_default_constructible<container_type>::value)
152 : c() {}
153
154 _LIBCPP_INLINE_VISIBILITY
155 stack(const stack& __q) : c(__q.c) {}
156
Eric Fiselier33cc2f02017-04-18 21:16:26 +0000157 _LIBCPP_INLINE_VISIBILITY
158 stack& operator=(const stack& __q) {c = __q.c; return *this;}
159
160
161#ifndef _LIBCPP_CXX03_LANG
Howard Hinnante0da4a12011-06-04 22:09:19 +0000162 _LIBCPP_INLINE_VISIBILITY
163 stack(stack&& __q)
164 _NOEXCEPT_(is_nothrow_move_constructible<container_type>::value)
Howard Hinnantb1ad5a82011-06-30 21:18:19 +0000165 : c(_VSTD::move(__q.c)) {}
Howard Hinnante0da4a12011-06-04 22:09:19 +0000166
167 _LIBCPP_INLINE_VISIBILITY
Howard Hinnante0da4a12011-06-04 22:09:19 +0000168 stack& operator=(stack&& __q)
169 _NOEXCEPT_(is_nothrow_move_assignable<container_type>::value)
Howard Hinnantb1ad5a82011-06-30 21:18:19 +0000170 {c = _VSTD::move(__q.c); return *this;}
Eric Fiselier33cc2f02017-04-18 21:16:26 +0000171
172 _LIBCPP_INLINE_VISIBILITY
173 explicit stack(container_type&& __c) : c(_VSTD::move(__c)) {}
Louis Dionne2b1ceaa2021-04-20 12:03:32 -0400174#endif // _LIBCPP_CXX03_LANG
Howard Hinnante0da4a12011-06-04 22:09:19 +0000175
Howard Hinnant186dca82010-09-23 17:31:07 +0000176 _LIBCPP_INLINE_VISIBILITY
Howard Hinnantc51e1022010-05-11 19:42:16 +0000177 explicit stack(const container_type& __c) : c(__c) {}
Eric Fiselier33cc2f02017-04-18 21:16:26 +0000178
Howard Hinnantc51e1022010-05-11 19:42:16 +0000179 template <class _Alloc>
Howard Hinnant186dca82010-09-23 17:31:07 +0000180 _LIBCPP_INLINE_VISIBILITY
Howard Hinnantc51e1022010-05-11 19:42:16 +0000181 explicit stack(const _Alloc& __a,
Louis Dionne9ce598d2021-09-08 09:14:43 -0400182 __enable_if_t<uses_allocator<container_type, _Alloc>::value>* = 0)
Howard Hinnantc51e1022010-05-11 19:42:16 +0000183 : c(__a) {}
184 template <class _Alloc>
Howard Hinnant186dca82010-09-23 17:31:07 +0000185 _LIBCPP_INLINE_VISIBILITY
Howard Hinnantc51e1022010-05-11 19:42:16 +0000186 stack(const container_type& __c, const _Alloc& __a,
Louis Dionne9ce598d2021-09-08 09:14:43 -0400187 __enable_if_t<uses_allocator<container_type, _Alloc>::value>* = 0)
Howard Hinnantc51e1022010-05-11 19:42:16 +0000188 : c(__c, __a) {}
189 template <class _Alloc>
Howard Hinnant186dca82010-09-23 17:31:07 +0000190 _LIBCPP_INLINE_VISIBILITY
Howard Hinnantc51e1022010-05-11 19:42:16 +0000191 stack(const stack& __s, const _Alloc& __a,
Louis Dionne9ce598d2021-09-08 09:14:43 -0400192 __enable_if_t<uses_allocator<container_type, _Alloc>::value>* = 0)
Howard Hinnantc51e1022010-05-11 19:42:16 +0000193 : c(__s.c, __a) {}
Eric Fiselier33cc2f02017-04-18 21:16:26 +0000194#ifndef _LIBCPP_CXX03_LANG
Howard Hinnantc51e1022010-05-11 19:42:16 +0000195 template <class _Alloc>
Howard Hinnant186dca82010-09-23 17:31:07 +0000196 _LIBCPP_INLINE_VISIBILITY
Howard Hinnantc51e1022010-05-11 19:42:16 +0000197 stack(container_type&& __c, const _Alloc& __a,
Louis Dionne9ce598d2021-09-08 09:14:43 -0400198 __enable_if_t<uses_allocator<container_type, _Alloc>::value>* = 0)
Howard Hinnantb1ad5a82011-06-30 21:18:19 +0000199 : c(_VSTD::move(__c), __a) {}
Howard Hinnantc51e1022010-05-11 19:42:16 +0000200 template <class _Alloc>
Howard Hinnant186dca82010-09-23 17:31:07 +0000201 _LIBCPP_INLINE_VISIBILITY
Howard Hinnantc51e1022010-05-11 19:42:16 +0000202 stack(stack&& __s, const _Alloc& __a,
Louis Dionne9ce598d2021-09-08 09:14:43 -0400203 __enable_if_t<uses_allocator<container_type, _Alloc>::value>* = 0)
Howard Hinnantb1ad5a82011-06-30 21:18:19 +0000204 : c(_VSTD::move(__s.c), __a) {}
Louis Dionne2b1ceaa2021-04-20 12:03:32 -0400205#endif // _LIBCPP_CXX03_LANG
Howard Hinnantc51e1022010-05-11 19:42:16 +0000206
Nikolas Klauserf0b3d872022-01-06 12:36:07 +0100207#if _LIBCPP_STD_VER > 20
208 template <class _InputIterator,
209 class = __enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>>
210 _LIBCPP_HIDE_FROM_ABI
211 stack(_InputIterator __first, _InputIterator __last) : c(__first, __last) {}
212
213 template <class _InputIterator,
214 class _Alloc,
215 class = __enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
216 class = __enable_if_t<uses_allocator<container_type, _Alloc>::value>>
217 _LIBCPP_HIDE_FROM_ABI
218 stack(_InputIterator __first, _InputIterator __last, const _Alloc& __alloc) : c(__first, __last, __alloc) {}
219#endif
220
Marshall Clow425f5752017-11-15 05:51:26 +0000221 _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
Howard Hinnantc51e1022010-05-11 19:42:16 +0000222 bool empty() const {return c.empty();}
Howard Hinnant186dca82010-09-23 17:31:07 +0000223 _LIBCPP_INLINE_VISIBILITY
Howard Hinnantc51e1022010-05-11 19:42:16 +0000224 size_type size() const {return c.size();}
Howard Hinnant186dca82010-09-23 17:31:07 +0000225 _LIBCPP_INLINE_VISIBILITY
Howard Hinnantc51e1022010-05-11 19:42:16 +0000226 reference top() {return c.back();}
Howard Hinnant186dca82010-09-23 17:31:07 +0000227 _LIBCPP_INLINE_VISIBILITY
Howard Hinnantc51e1022010-05-11 19:42:16 +0000228 const_reference top() const {return c.back();}
229
Howard Hinnant186dca82010-09-23 17:31:07 +0000230 _LIBCPP_INLINE_VISIBILITY
Howard Hinnantc51e1022010-05-11 19:42:16 +0000231 void push(const value_type& __v) {c.push_back(__v);}
Eric Fiselier33cc2f02017-04-18 21:16:26 +0000232#ifndef _LIBCPP_CXX03_LANG
Howard Hinnant186dca82010-09-23 17:31:07 +0000233 _LIBCPP_INLINE_VISIBILITY
Howard Hinnantb1ad5a82011-06-30 21:18:19 +0000234 void push(value_type&& __v) {c.push_back(_VSTD::move(__v));}
Eric Fiselier33cc2f02017-04-18 21:16:26 +0000235
Howard Hinnant186dca82010-09-23 17:31:07 +0000236 template <class... _Args>
237 _LIBCPP_INLINE_VISIBILITY
Marshall Clowea52cc42017-01-24 23:09:12 +0000238#if _LIBCPP_STD_VER > 14
Marshall Clow88746852018-01-24 22:42:25 +0000239 decltype(auto) emplace(_Args&&... __args)
Eric Fiselier34ba5b92016-07-21 03:20:17 +0000240 { return c.emplace_back(_VSTD::forward<_Args>(__args)...);}
Marshall Clowea52cc42017-01-24 23:09:12 +0000241#else
242 void emplace(_Args&&... __args)
243 { c.emplace_back(_VSTD::forward<_Args>(__args)...);}
244#endif
Louis Dionne2b1ceaa2021-04-20 12:03:32 -0400245#endif // _LIBCPP_CXX03_LANG
Eric Fiselier33cc2f02017-04-18 21:16:26 +0000246
Howard Hinnant186dca82010-09-23 17:31:07 +0000247 _LIBCPP_INLINE_VISIBILITY
Howard Hinnantc51e1022010-05-11 19:42:16 +0000248 void pop() {c.pop_back();}
249
Howard Hinnant186dca82010-09-23 17:31:07 +0000250 _LIBCPP_INLINE_VISIBILITY
Howard Hinnantc51e1022010-05-11 19:42:16 +0000251 void swap(stack& __s)
Howard Hinnante0da4a12011-06-04 22:09:19 +0000252 _NOEXCEPT_(__is_nothrow_swappable<container_type>::value)
Howard Hinnantc51e1022010-05-11 19:42:16 +0000253 {
Howard Hinnantb1ad5a82011-06-30 21:18:19 +0000254 using _VSTD::swap;
Howard Hinnantc51e1022010-05-11 19:42:16 +0000255 swap(c, __s.c);
256 }
257
258 template <class T1, class _C1>
259 friend
260 bool
261 operator==(const stack<T1, _C1>& __x, const stack<T1, _C1>& __y);
Howard Hinnant3b6579a2010-08-22 00:02:43 +0000262
Howard Hinnantc51e1022010-05-11 19:42:16 +0000263 template <class T1, class _C1>
264 friend
265 bool
266 operator< (const stack<T1, _C1>& __x, const stack<T1, _C1>& __y);
267};
268
Nikolas Klauserf0b3d872022-01-06 12:36:07 +0100269#if _LIBCPP_STD_VER > 14
Marshall Clow592d9952018-05-22 01:57:53 +0000270template<class _Container,
Louis Dionne25547162021-08-17 12:26:09 -0400271 class = enable_if_t<!__is_allocator<_Container>::value>
Marshall Clow592d9952018-05-22 01:57:53 +0000272>
273stack(_Container)
274 -> stack<typename _Container::value_type, _Container>;
Louis Dionne173f29e2019-05-29 16:01:36 +0000275
Marshall Clow592d9952018-05-22 01:57:53 +0000276template<class _Container,
277 class _Alloc,
Louis Dionne25547162021-08-17 12:26:09 -0400278 class = enable_if_t<!__is_allocator<_Container>::value>,
279 class = enable_if_t<uses_allocator<_Container, _Alloc>::value>
Louis Dionne173f29e2019-05-29 16:01:36 +0000280 >
Marshall Clow592d9952018-05-22 01:57:53 +0000281stack(_Container, _Alloc)
282 -> stack<typename _Container::value_type, _Container>;
283#endif
284
Nikolas Klauserf0b3d872022-01-06 12:36:07 +0100285#if _LIBCPP_STD_VER > 20
286template<class _InputIterator,
287 class = __enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>>
288stack(_InputIterator, _InputIterator)
289 -> stack<__iter_value_type<_InputIterator>>;
290
291template<class _InputIterator,
292 class _Alloc,
293 class = __enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
294 class = __enable_if_t<__is_allocator<_Alloc>::value>>
295stack(_InputIterator, _InputIterator, _Alloc)
296 -> stack<__iter_value_type<_InputIterator>, deque<__iter_value_type<_InputIterator>, _Alloc>>;
297#endif
298
Howard Hinnantc51e1022010-05-11 19:42:16 +0000299template <class _Tp, class _Container>
Howard Hinnant186dca82010-09-23 17:31:07 +0000300inline _LIBCPP_INLINE_VISIBILITY
Howard Hinnantc51e1022010-05-11 19:42:16 +0000301bool
302operator==(const stack<_Tp, _Container>& __x, const stack<_Tp, _Container>& __y)
303{
304 return __x.c == __y.c;
305}
306
307template <class _Tp, class _Container>
Howard Hinnant186dca82010-09-23 17:31:07 +0000308inline _LIBCPP_INLINE_VISIBILITY
Howard Hinnantc51e1022010-05-11 19:42:16 +0000309bool
310operator< (const stack<_Tp, _Container>& __x, const stack<_Tp, _Container>& __y)
311{
312 return __x.c < __y.c;
313}
314
315template <class _Tp, class _Container>
Howard Hinnant186dca82010-09-23 17:31:07 +0000316inline _LIBCPP_INLINE_VISIBILITY
Howard Hinnantc51e1022010-05-11 19:42:16 +0000317bool
318operator!=(const stack<_Tp, _Container>& __x, const stack<_Tp, _Container>& __y)
319{
320 return !(__x == __y);
321}
322
323template <class _Tp, class _Container>
Howard Hinnant186dca82010-09-23 17:31:07 +0000324inline _LIBCPP_INLINE_VISIBILITY
Howard Hinnantc51e1022010-05-11 19:42:16 +0000325bool
326operator> (const stack<_Tp, _Container>& __x, const stack<_Tp, _Container>& __y)
327{
328 return __y < __x;
329}
330
331template <class _Tp, class _Container>
Howard Hinnant186dca82010-09-23 17:31:07 +0000332inline _LIBCPP_INLINE_VISIBILITY
Howard Hinnantc51e1022010-05-11 19:42:16 +0000333bool
334operator>=(const stack<_Tp, _Container>& __x, const stack<_Tp, _Container>& __y)
335{
336 return !(__x < __y);
337}
338
339template <class _Tp, class _Container>
Howard Hinnant186dca82010-09-23 17:31:07 +0000340inline _LIBCPP_INLINE_VISIBILITY
Howard Hinnantc51e1022010-05-11 19:42:16 +0000341bool
342operator<=(const stack<_Tp, _Container>& __x, const stack<_Tp, _Container>& __y)
343{
344 return !(__y < __x);
345}
346
347template <class _Tp, class _Container>
Howard Hinnant186dca82010-09-23 17:31:07 +0000348inline _LIBCPP_INLINE_VISIBILITY
Louis Dionne9ce598d2021-09-08 09:14:43 -0400349__enable_if_t<__is_swappable<_Container>::value, void>
Howard Hinnantc51e1022010-05-11 19:42:16 +0000350swap(stack<_Tp, _Container>& __x, stack<_Tp, _Container>& __y)
Howard Hinnante0da4a12011-06-04 22:09:19 +0000351 _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
Howard Hinnantc51e1022010-05-11 19:42:16 +0000352{
353 __x.swap(__y);
354}
355
356template <class _Tp, class _Container, class _Alloc>
Eric Fiselierb5eb1bf2017-01-04 23:56:00 +0000357struct _LIBCPP_TEMPLATE_VIS uses_allocator<stack<_Tp, _Container>, _Alloc>
Howard Hinnantc51e1022010-05-11 19:42:16 +0000358 : public uses_allocator<_Container, _Alloc>
359{
360};
361
362_LIBCPP_END_NAMESPACE_STD
363
Mark de Weveree5fe272022-09-02 17:53:28 +0200364#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
365# include <functional>
366#endif
367
Louis Dionne2b1ceaa2021-04-20 12:03:32 -0400368#endif // _LIBCPP_STACK