summaryrefslogtreecommitdiffstats
path: root/src/corelib/tools/qstack.cpp
blob: 224f72926b32e46cec74a4a625c5c8a277e3e5b6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
/****************************************************************************
**
** Copyright (C) 2015 The Qt Company Ltd.
** Contact: http://www.qt.io/licensing/
**
** This file is part of the QtCore module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL21$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see http://www.qt.io/terms-conditions. For further
** information use the contact form at http://www.qt.io/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 or version 3 as published by the Free
** Software Foundation and appearing in the file LICENSE.LGPLv21 and
** LICENSE.LGPLv3 included in the packaging of this file. Please review the
** following information to ensure the GNU Lesser General Public License
** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** As a special exception, The Qt Company gives you certain additional
** rights. These rights are described in The Qt Company LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** $QT_END_LICENSE$
**
****************************************************************************/

/*!
    \class QStack
    \inmodule QtCore
    \brief The QStack class is a template class that provides a stack.

    \ingroup tools
    \ingroup shared

    \reentrant

    QStack\<T\> is one of Qt's generic \l{container classes}. It implements
    a stack data structure for items of a same type.

    A stack is a last in, first out (LIFO) structure. Items are added
    to the top of the stack using push() and retrieved from the top
    using pop(). The top() function provides access to the topmost
    item without removing it.

    Example:

    \snippet qstack/main.cpp 0

    The example will output 3, 2, 1 in that order.

    QStack inherits from QVector. All of QVector's functionality also
    applies to QStack. For example, you can use isEmpty() to test
    whether the stack is empty, and you can traverse a QStack using
    QVector's iterator classes (for example, QVectorIterator). But in
    addition, QStack provides three convenience functions that make
    it easy to implement LIFO semantics: push(), pop(), and top().

    QStack's value type must be an \l{assignable data type}. This
    covers most data types that are commonly used, but the compiler
    won't let you, for example, store a QWidget as a value; instead,
    store a QWidget *.

    \sa QVector, QQueue
*/

/*!
    \fn void QStack::swap(QStack<T> &other)
    \since 4.8

    Swaps stack \a other with this stack. This operation is very fast and
    never fails.
*/

/*!
    \fn void QStack::push(const T& t)

    Adds element \a t to the top of the stack.

    This is the same as QVector::append().

    \sa pop(), top()
*/

/*!
    \fn T& QStack::top()

    Returns a reference to the stack's top item. This function
    assumes that the stack isn't empty.

    This is the same as QVector::last().

    \sa pop(), push(), isEmpty()
*/

/*!
    \fn const T& QStack::top() const

    \overload

    \sa pop(), push()
*/

/*!
    \fn T QStack::pop()

    Removes the top item from the stack and returns it. This function
    assumes that the stack isn't empty.

    \sa top(), push(), isEmpty()
*/