# stl_stack.h

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    00001 // Stack implementation -*- C++ -*-
    00002
    00003 // Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
    00004 // Free Software Foundation, Inc.
    00005 //
    00006 // This file is part of the GNU ISO C++ Library.  This library is free
    00007 // software; you can redistribute it and/or modify it under the
    00008 // terms of the GNU General Public License as published by the
    00009 // Free Software Foundation; either version 3, or (at your option)
    00010 // any later version.
    00011
    00012 // This library is distributed in the hope that it will be useful,
    00013 // but WITHOUT ANY WARRANTY; without even the implied warranty of
    00014 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    00015 // GNU General Public License for more details.
    00016
    00017 // Under Section 7 of GPL version 3, you are granted additional
    00018 // permissions described in the GCC Runtime Library Exception, version
    00019 // 3.1, as published by the Free Software Foundation.
    00020
    00021 // You should have received a copy of the GNU General Public License and
    00022 // a copy of the GCC Runtime Library Exception along with this program;
    00023 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
    00024 // <http://www.gnu.org/licenses/>.
    00025
    00026 /*
    00027  *
    00028  * Copyright (c) 1994
    00029  * Hewlett-Packard Company
    00030  *
    00031  * Permission to use, copy, modify, distribute and sell this software
    00032  * and its documentation for any purpose is hereby granted without fee,
    00033  * provided that the above copyright notice appear in all copies and
    00034  * that both that copyright notice and this permission notice appear
    00035  * in supporting documentation.  Hewlett-Packard Company makes no
    00036  * representations about the suitability of this software for any
    00037  * purpose.  It is provided "as is" without express or implied warranty.
    00038  *
    00039  *
    00040  * Copyright (c) 1996,1997
    00041  * Silicon Graphics Computer Systems, Inc.
    00042  *
    00043  * Permission to use, copy, modify, distribute and sell this software
    00044  * and its documentation for any purpose is hereby granted without fee,
    00045  * provided that the above copyright notice appear in all copies and
    00046  * that both that copyright notice and this permission notice appear
    00047  * in supporting documentation.  Silicon Graphics makes no
    00048  * representations about the suitability of this software for any
    00049  * purpose.  It is provided "as is" without express or implied warranty.
    00050  */
    00051
    00052 /** @file stl_stack.h
    00053  *  This is an internal header file, included by other library headers.
    00054  *  You should not attempt to use it directly.
    00055  */
    00056
    00057 #ifndef _STL_STACK_H
    00058 #define _STL_STACK_H 1
    00059
    00060 #include <bits/concept_check.h>
    00061 #include <debug/debug.h>
    00062
    00063 _GLIBCXX_BEGIN_NAMESPACE(std)
    00064
    00065   /**
    00066    *  @brief  A standard container giving FILO behavior.
    00067    *
    00068    *  @ingroup sequences
    00069    *
    00070    *  Meets many of the requirements of a
    00071    *  <a href="tables.html#65">container</a>,
    00072    *  but does not define anything to do with iterators.  Very few of the
    00073    *  other standard container interfaces are defined.
    00074    *
    00075    *  This is not a true container, but an @e adaptor.  It holds
    00076    *  another container, and provides a wrapper interface to that
    00077    *  container.  The wrapper is what enforces strict
    00078    *  first-in-last-out %stack behavior.
    00079    *
    00080    *  The second template parameter defines the type of the underlying
    00081    *  sequence/container.  It defaults to std::deque, but it can be
    00082    *  any type that supports @c back, @c push_back, and @c pop_front,
    00083    *  such as std::list, std::vector, or an appropriate user-defined
    00084    *  type.
    00085    *
    00086    *  Members not found in @a normal containers are @c container_type,
    00087    *  which is a typedef for the second Sequence parameter, and @c
    00088    *  push, @c pop, and @c top, which are standard %stack/FILO
    00089    *  operations.
    00090   */
    00091   template<typename _Tp, typename _Sequence = deque<_Tp> >
    00092     class stack
    00093     {
    00094       // concept requirements
    00095       typedef typename _Sequence::value_type _Sequence_value_type;
    00096       __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
    00097       __glibcxx_class_requires(_Sequence, _BackInsertionSequenceConcept)
    00098       __glibcxx_class_requires2(_Tp, _Sequence_value_type, _SameTypeConcept)
    00099
    00100       template<typename _Tp1, typename _Seq1>
    00101         friend bool
    00102         operator==(const stack<_Tp1, _Seq1>&, const stack<_Tp1, _Seq1>&);
    00103
    00104       template<typename _Tp1, typename _Seq1>
    00105         friend bool
    00106         operator<(const stack<_Tp1, _Seq1>&, const stack<_Tp1, _Seq1>&);
    00107
    00108     public:
    00109       typedef typename _Sequence::value_type                value_type;
    00110       typedef typename _Sequence::reference                 reference;
    00111       typedef typename _Sequence::const_reference           const_reference;
    00112       typedef typename _Sequence::size_type                 size_type;
    00113       typedef          _Sequence                            container_type;
    00114
    00115     protected:
    00116       //  See queue::c for notes on this name.
    00117       _Sequence c;
    00118
    00119     public:
    00120       // XXX removed old def ctor, added def arg to this one to match 14882
    00121       /**
    00122        *  @brief  Default constructor creates no elements.
    00123        */
    00124 #ifndef __GXX_EXPERIMENTAL_CXX0X__
    00125       explicit
    00126       stack(const _Sequence& __c = _Sequence())
    00127       : c(__c) { }
    00128 #else
    00129       explicit
    00130       stack(const _Sequence& __c)
    00131       : c(__c) { }
    00132
    00133       explicit
    00134       stack(_Sequence&& __c = _Sequence())
    00135       : c(std::move(__c)) { }
    00136 #endif
    00137
    00138       /**
    00139        *  Returns true if the %stack is empty.
    00140        */
    00141       bool
    00142       empty() const
    00143       { return c.empty(); }
    00144
    00145       /**  Returns the number of elements in the %stack.  */
    00146       size_type
    00147       size() const
    00148       { return c.size(); }
    00149
    00150       /**
    00151        *  Returns a read/write reference to the data at the first
    00152        *  element of the %stack.
    00153        */
    00154       reference
    00155       top()
    00156       {
    00157     __glibcxx_requires_nonempty();
    00158     return c.back();
    00159       }
    00160
    00161       /**
    00162        *  Returns a read-only (constant) reference to the data at the first
    00163        *  element of the %stack.
    00164        */
    00165       const_reference
    00166       top() const
    00167       {
    00168     __glibcxx_requires_nonempty();
    00169     return c.back();
    00170       }
    00171
    00172       /**
    00173        *  @brief  Add data to the top of the %stack.
    00174        *  @param  x  Data to be added.
    00175        *
    00176        *  This is a typical %stack operation.  The function creates an
    00177        *  element at the top of the %stack and assigns the given data
    00178        *  to it.  The time complexity of the operation depends on the
    00179        *  underlying sequence.
    00180        */
    00181       void
    00182       push(const value_type& __x)
    00183       { c.push_back(__x); }
    00184
    00185 #ifdef __GXX_EXPERIMENTAL_CXX0X__
    00186       void
    00187       push(value_type&& __x)
    00188       { c.push_back(std::move(__x)); }
    00189
    00190       template<typename... _Args>
    00191         void
    00192         emplace(_Args&&... __args)
    00193     { c.emplace_back(std::forward<_Args>(__args)...); }
    00194 #endif
    00195
    00196       /**
    00197        *  @brief  Removes first element.
    00198        *
    00199        *  This is a typical %stack operation.  It shrinks the %stack
    00200        *  by one.  The time complexity of the operation depends on the
    00201        *  underlying sequence.
    00202        *
    00203        *  Note that no data is returned, and if the first element's
    00204        *  data is needed, it should be retrieved before pop() is
    00205        *  called.
    00206        */
    00207       void
    00208       pop()
    00209       {
    00210     __glibcxx_requires_nonempty();
    00211     c.pop_back();
    00212       }
    00213
    00214 #ifdef __GXX_EXPERIMENTAL_CXX0X__
    00215       void
    00216       swap(stack& __s)
    00217       { c.swap(__s.c); }
    00218 #endif
    00219     };
    00220
    00221   /**
    00222    *  @brief  Stack equality comparison.
    00223    *  @param  x  A %stack.
    00224    *  @param  y  A %stack of the same type as @a x.
    00225    *  @return  True iff the size and elements of the stacks are equal.
    00226    *
    00227    *  This is an equivalence relation.  Complexity and semantics
    00228    *  depend on the underlying sequence type, but the expected rules
    00229    *  are: this relation is linear in the size of the sequences, and
    00230    *  stacks are considered equivalent if their sequences compare
    00231    *  equal.
    00232   */
    00233   template<typename _Tp, typename _Seq>
    00234     inline bool
    00235     operator==(const stack<_Tp, _Seq>& __x, const stack<_Tp, _Seq>& __y)
    00236     { return __x.c == __y.c; }
    00237
    00238   /**
    00239    *  @brief  Stack ordering relation.
    00240    *  @param  x  A %stack.
    00241    *  @param  y  A %stack of the same type as @a x.
    00242    *  @return  True iff @a x is lexicographically less than @a y.
    00243    *
    00244    *  This is an total ordering relation.  Complexity and semantics
    00245    *  depend on the underlying sequence type, but the expected rules
    00246    *  are: this relation is linear in the size of the sequences, the
    00247    *  elements must be comparable with @c <, and
    00248    *  std::lexicographical_compare() is usually used to make the
    00249    *  determination.
    00250   */
    00251   template<typename _Tp, typename _Seq>
    00252     inline bool
    00253     operator<(const stack<_Tp, _Seq>& __x, const stack<_Tp, _Seq>& __y)
    00254     { return __x.c < __y.c; }
    00255
    00256   /// Based on operator==
    00257   template<typename _Tp, typename _Seq>
    00258     inline bool
    00259     operator!=(const stack<_Tp, _Seq>& __x, const stack<_Tp, _Seq>& __y)
    00260     { return !(__x == __y); }
    00261
    00262   /// Based on operator<
    00263   template<typename _Tp, typename _Seq>
    00264     inline bool
    00265     operator>(const stack<_Tp, _Seq>& __x, const stack<_Tp, _Seq>& __y)
    00266     { return __y < __x; }
    00267
    00268   /// Based on operator<
    00269   template<typename _Tp, typename _Seq>
    00270     inline bool
    00271     operator<=(const stack<_Tp, _Seq>& __x, const stack<_Tp, _Seq>& __y)
    00272     { return !(__y < __x); }
    00273
    00274   /// Based on operator<
    00275   template<typename _Tp, typename _Seq>
    00276     inline bool
    00277     operator>=(const stack<_Tp, _Seq>& __x, const stack<_Tp, _Seq>& __y)
    00278     { return !(__x < __y); }
    00279
    00280 #ifdef __GXX_EXPERIMENTAL_CXX0X__
    00281   template<typename _Tp, typename _Seq>
    00282     inline void
    00283     swap(stack<_Tp, _Seq>& __x, stack<_Tp, _Seq>& __y)
    00284     { __x.swap(__y); }
    00285 #endif
    00286
    00287 _GLIBCXX_END_NAMESPACE
    00288
    00289 #endif /* _STL_STACK_H */