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- // Stack implementation -*- C++ -*-
-
- // Copyright (C) 2001, 2002, 2004 Free Software Foundation, Inc.
- //
- // This file is part of the GNU ISO C++ Library. This library is free
- // software; you can redistribute it and/or modify it under the
- // terms of the GNU General Public License as published by the
- // Free Software Foundation; either version 2, or (at your option)
- // any later version.
-
- // This library is distributed in the hope that it will be useful,
- // but WITHOUT ANY WARRANTY; without even the implied warranty of
- // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- // GNU General Public License for more details.
-
- // You should have received a copy of the GNU General Public License along
- // with this library; see the file COPYING. If not, write to the Free
- // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
- // USA.
-
- // As a special exception, you may use this file as part of a free software
- // library without restriction. Specifically, if other files instantiate
- // templates or use macros or inline functions from this file, or you compile
- // this file and link it with other files to produce an executable, this
- // file does not by itself cause the resulting executable to be covered by
- // the GNU General Public License. This exception does not however
- // invalidate any other reasons why the executable file might be covered by
- // the GNU General Public License.
-
- /*
- *
- * Copyright (c) 1994
- * Hewlett-Packard Company
- *
- * Permission to use, copy, modify, distribute and sell this software
- * and its documentation for any purpose is hereby granted without fee,
- * provided that the above copyright notice appear in all copies and
- * that both that copyright notice and this permission notice appear
- * in supporting documentation. Hewlett-Packard Company makes no
- * representations about the suitability of this software for any
- * purpose. It is provided "as is" without express or implied warranty.
- *
- *
- * Copyright (c) 1996,1997
- * Silicon Graphics Computer Systems, Inc.
- *
- * Permission to use, copy, modify, distribute and sell this software
- * and its documentation for any purpose is hereby granted without fee,
- * provided that the above copyright notice appear in all copies and
- * that both that copyright notice and this permission notice appear
- * in supporting documentation. Silicon Graphics makes no
- * representations about the suitability of this software for any
- * purpose. It is provided "as is" without express or implied warranty.
- */
-
- /** @file stl_stack.h
- * This is an internal header file, included by other library headers.
- * You should not attempt to use it directly.
- */
-
- #ifndef _STACK_H
- #define _STACK_H 1
-
- #include <bits/concept_check.h>
- #include <debug/debug.h>
-
- namespace std
- {
- // Forward declarations of operators == and <, needed for friend
- // declaration.
- template<typename _Tp, typename _Sequence = deque<_Tp> >
- class stack;
-
- template<typename _Tp, typename _Seq>
- inline bool
- operator==(const stack<_Tp,_Seq>& __x, const stack<_Tp,_Seq>& __y);
-
- template<typename _Tp, typename _Seq>
- inline bool
- operator<(const stack<_Tp,_Seq>& __x, const stack<_Tp,_Seq>& __y);
-
- /**
- * @brief A standard container giving FILO behavior.
- *
- * @ingroup Containers
- * @ingroup Sequences
- *
- * Meets many of the requirements of a
- * <a href="tables.html#65">container</a>,
- * but does not define anything to do with iterators. Very few of the
- * other standard container interfaces are defined.
- *
- * This is not a true container, but an @e adaptor. It holds
- * another container, and provides a wrapper interface to that
- * container. The wrapper is what enforces strict
- * first-in-last-out %stack behavior.
- *
- * The second template parameter defines the type of the underlying
- * sequence/container. It defaults to std::deque, but it can be
- * any type that supports @c back, @c push_back, and @c pop_front,
- * such as std::list, std::vector, or an appropriate user-defined
- * type.
- *
- * Members not found in "normal" containers are @c container_type,
- * which is a typedef for the second Sequence parameter, and @c
- * push, @c pop, and @c top, which are standard %stack/FILO
- * operations.
- */
- template<typename _Tp, typename _Sequence>
- class stack
- {
- // concept requirements
- typedef typename _Sequence::value_type _Sequence_value_type;
- __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
- __glibcxx_class_requires(_Sequence, _BackInsertionSequenceConcept)
- __glibcxx_class_requires2(_Tp, _Sequence_value_type, _SameTypeConcept)
-
- template<typename _Tp1, typename _Seq1>
- friend bool
- operator==(const stack<_Tp1, _Seq1>&, const stack<_Tp1, _Seq1>&);
-
- template<typename _Tp1, typename _Seq1>
- friend bool
- operator<(const stack<_Tp1, _Seq1>&, const stack<_Tp1, _Seq1>&);
-
- public:
- typedef typename _Sequence::value_type value_type;
- typedef typename _Sequence::reference reference;
- typedef typename _Sequence::const_reference const_reference;
- typedef typename _Sequence::size_type size_type;
- typedef _Sequence container_type;
-
- protected:
- // See queue::c for notes on this name.
- _Sequence c;
-
- public:
- // XXX removed old def ctor, added def arg to this one to match 14882
- /**
- * @brief Default constructor creates no elements.
- */
- explicit
- stack(const _Sequence& __c = _Sequence())
- : c(__c) {}
-
- /**
- * Returns true if the %stack is empty.
- */
- bool
- empty() const
- { return c.empty(); }
-
- /** Returns the number of elements in the %stack. */
- size_type
- size() const
- { return c.size(); }
-
- /**
- * Returns a read/write reference to the data at the first
- * element of the %stack.
- */
- reference
- top()
- {
- __glibcxx_requires_nonempty();
- return c.back();
- }
-
- /**
- * Returns a read-only (constant) reference to the data at the first
- * element of the %stack.
- */
- const_reference
- top() const
- {
- __glibcxx_requires_nonempty();
- return c.back();
- }
-
- /**
- * @brief Add data to the top of the %stack.
- * @param x Data to be added.
- *
- * This is a typical %stack operation. The function creates an
- * element at the top of the %stack and assigns the given data
- * to it. The time complexity of the operation depends on the
- * underlying sequence.
- */
- void
- push(const value_type& __x)
- { c.push_back(__x); }
-
- /**
- * @brief Removes first element.
- *
- * This is a typical %stack operation. It shrinks the %stack
- * by one. The time complexity of the operation depends on the
- * underlying sequence.
- *
- * Note that no data is returned, and if the first element's
- * data is needed, it should be retrieved before pop() is
- * called.
- */
- void
- pop()
- {
- __glibcxx_requires_nonempty();
- c.pop_back();
- }
- };
-
- /**
- * @brief Stack equality comparison.
- * @param x A %stack.
- * @param y A %stack of the same type as @a x.
- * @return True iff the size and elements of the stacks are equal.
- *
- * This is an equivalence relation. Complexity and semantics
- * depend on the underlying sequence type, but the expected rules
- * are: this relation is linear in the size of the sequences, and
- * stacks are considered equivalent if their sequences compare
- * equal.
- */
- template<typename _Tp, typename _Seq>
- inline bool
- operator==(const stack<_Tp, _Seq>& __x, const stack<_Tp, _Seq>& __y)
- { return __x.c == __y.c; }
-
- /**
- * @brief Stack ordering relation.
- * @param x A %stack.
- * @param y A %stack of the same type as @a x.
- * @return True iff @a x is lexicographically less than @a y.
- *
- * This is an total ordering relation. Complexity and semantics
- * depend on the underlying sequence type, but the expected rules
- * are: this relation is linear in the size of the sequences, the
- * elements must be comparable with @c <, and
- * std::lexicographical_compare() is usually used to make the
- * determination.
- */
- template<typename _Tp, typename _Seq>
- inline bool
- operator<(const stack<_Tp, _Seq>& __x, const stack<_Tp, _Seq>& __y)
- { return __x.c < __y.c; }
-
- /// Based on operator==
- template<typename _Tp, typename _Seq>
- inline bool
- operator!=(const stack<_Tp, _Seq>& __x, const stack<_Tp, _Seq>& __y)
- { return !(__x == __y); }
-
- /// Based on operator<
- template<typename _Tp, typename _Seq>
- inline bool
- operator>(const stack<_Tp, _Seq>& __x, const stack<_Tp, _Seq>& __y)
- { return __y < __x; }
-
- /// Based on operator<
- template<typename _Tp, typename _Seq>
- inline bool
- operator<=(const stack<_Tp, _Seq>& __x, const stack<_Tp, _Seq>& __y)
- { return !(__y < __x); }
-
- /// Based on operator<
- template<typename _Tp, typename _Seq>
- inline bool
- operator>=(const stack<_Tp, _Seq>& __x, const stack<_Tp, _Seq>& __y)
- { return !(__x < __y); }
- } // namespace std
-
- #endif /* _STACK_H */
-