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Breadcrumbs go here --> <li><a href="modules.html">Modules</a></li> <li><a href="qtcore.html">QtCore</a></li> <li>QStack</li> </ul> </div> <div class="toolbuttons toolblock"> <ul> <li id="smallA" class="t_button">A</li> <li id="medA" class="t_button active">A</li> <li id="bigA" class="t_button">A</li> <li id="print" class="t_button"><a href="javascript:this.print();"> <span>Print</span></a></li> </ul> </div> </div> <div class="content mainContent"> <div class="toc"> <h3><a name="toc">Contents</a></h3> <ul> <li class="level1"><a href="#public-functions">Public Functions</a></li> <li class="level1"><a href="#details">Detailed Description</a></li> </ul> </div> <h1 class="title">QStack Class Reference</h1> <!-- $$$QStack-brief --> <p>The QStack class is a template class that provides a stack. <a href="#details">More...</a></p> <!-- @@@QStack --> <pre class="cpp"> <span class="preprocessor">#include <QStack></span></pre><p><b>Inherits: </b><a href="qvector.html">QVector<T></a>.</p> <p><b>Note:</b> All functions in this class are <a href="threads-reentrancy.html#reentrant">reentrant</a>.</p> <ul> <li><a href="qstack-members.html">List of all members, including inherited members</a></li> </ul> <a name="public-functions"></a> <h2>Public Functions</h2> <table class="alignedsummary"> <tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qstack.html#QStack">QStack</a></b> ()</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qstack.html#dtor.QStack">~QStack</a></b> ()</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> T </td><td class="memItemRight bottomAlign"><b><a href="qstack.html#pop">pop</a></b> ()</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qstack.html#push">push</a></b> ( const T & <i>t</i> )</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qstack.html#swap">swap</a></b> ( QStack<T> & <i>other</i> )</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> T & </td><td class="memItemRight bottomAlign"><b><a href="qstack.html#top">top</a></b> ()</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> const T & </td><td class="memItemRight bottomAlign"><b><a href="qstack.html#top-2">top</a></b> () const</td></tr> </table> <ul> <li class="fn">65 public functions inherited from <a href="qvector.html#public-functions">QVector</a></li> </ul> <h3>Additional Inherited Members</h3> <ul> <li class="fn">2 static public members inherited from <a href="qvector.html#static-public-members">QVector</a></li> </ul> <a name="details"></a> <!-- $$$QStack-description --> <div class="descr"> <h2>Detailed Description</h2> <p>The QStack class is a template class that provides a stack.</p> <p>QStack<T> is one of Qt's generic <a href="containers.html">container classes</a>. It implements a stack data structure for items of a same type.</p> <p>A stack is a last in, first out (LIFO) structure. Items are added to the top of the stack using <a href="qstack.html#push">push</a>() and retrieved from the top using <a href="qstack.html#pop">pop</a>(). The <a href="qstack.html#top">top</a>() function provides access to the topmost item without removing it.</p> <p>Example:</p> <pre class="cpp"> <span class="type">QStack</span><span class="operator"><</span><span class="type">int</span><span class="operator">></span> stack; stack<span class="operator">.</span>push(<span class="number">1</span>); stack<span class="operator">.</span>push(<span class="number">2</span>); stack<span class="operator">.</span>push(<span class="number">3</span>); <span class="keyword">while</span> (<span class="operator">!</span>stack<span class="operator">.</span>isEmpty()) cout <span class="operator"><</span><span class="operator"><</span> stack<span class="operator">.</span>pop() <span class="operator"><</span><span class="operator"><</span> endl;</pre> <p>The example will output 3, 2, 1 in that order.</p> <p>QStack inherits from <a href="qvector.html">QVector</a>. All of <a href="qvector.html">QVector</a>'s functionality also applies to QStack. For example, you can use <a href="qvector.html#isEmpty">isEmpty</a>() to test whether the stack is empty, and you can traverse a QStack using <a href="qvector.html">QVector</a>'s iterator classes (for example, <a href="qvectoriterator.html">QVectorIterator</a>). But in addition, QStack provides three convenience functions that make it easy to implement LIFO semantics: <a href="qstack.html#push">push</a>(), <a href="qstack.html#pop">pop</a>(), and <a href="qstack.html#top">top</a>().</p> <p>QStack's value type must be an <a href="containers.html#assignable-data-type">assignable data type</a>. This covers most data types that are commonly used, but the compiler won't let you, for example, store a <a href="qwidget.html">QWidget</a> as a value; instead, store a <a href="qwidget.html">QWidget</a> *.</p> </div> <p><b>See also </b><a href="qvector.html">QVector</a> and <a href="qqueue.html">QQueue</a>.</p> <!-- @@@QStack --> <div class="func"> <h2>Member Function Documentation</h2> <!-- $$$QStack[overload1]$$$QStack --> <h3 class="fn"><a name="QStack"></a>QStack::<span class="name">QStack</span> ()</h3> <p>Constructs an empty stack.</p> <!-- @@@QStack --> <!-- $$$~QStack[overload1]$$$~QStack --> <h3 class="fn"><a name="dtor.QStack"></a>QStack::<span class="name">~QStack</span> ()</h3> <p>Destroys the stack. References to the values in the stack, and all iterators over this stack, become invalid.</p> <!-- @@@~QStack --> <!-- $$$pop[overload1]$$$pop --> <h3 class="fn"><a name="pop"></a><span class="type">T</span> QStack::<span class="name">pop</span> ()</h3> <p>Removes the top item from the stack and returns it. This function assumes that the stack isn't empty.</p> <p><b>See also </b><a href="qstack.html#top">top</a>(), <a href="qstack.html#push">push</a>(), and <a href="qvector.html#isEmpty">isEmpty</a>().</p> <!-- @@@pop --> <!-- $$$push[overload1]$$$pushconstT& --> <h3 class="fn"><a name="push"></a><span class="type">void</span> QStack::<span class="name">push</span> ( const <span class="type">T</span> & <i>t</i> )</h3> <p>Adds element <i>t</i> to the top of the stack.</p> <p>This is the same as <a href="qvector.html#append">QVector::append</a>().</p> <p><b>See also </b><a href="qstack.html#pop">pop</a>() and <a href="qstack.html#top">top</a>().</p> <!-- @@@push --> <!-- $$$swap[overload1]$$$swapQStack<T>& --> <h3 class="fn"><a name="swap"></a><span class="type">void</span> QStack::<span class="name">swap</span> ( <span class="type">QStack</span><<span class="type">T</span>> & <i>other</i> )</h3> <p>Swaps stack <i>other</i> with this stack. This operation is very fast and never fails.</p> <p>This function was introduced in Qt 4.8.</p> <!-- @@@swap --> <!-- $$$top[overload1]$$$top --> <h3 class="fn"><a name="top"></a><span class="type">T</span> & QStack::<span class="name">top</span> ()</h3> <p>Returns a reference to the stack's top item. This function assumes that the stack isn't empty.</p> <p>This is the same as <a href="qvector.html#last">QVector::last</a>().</p> <p><b>See also </b><a href="qstack.html#pop">pop</a>(), <a href="qstack.html#push">push</a>(), and <a href="qvector.html#isEmpty">isEmpty</a>().</p> <!-- @@@top --> <!-- $$$top$$$top --> <h3 class="fn"><a name="top-2"></a>const <span class="type">T</span> & QStack::<span class="name">top</span> () const</h3> <p>This is an overloaded function.</p> <p><b>See also </b><a href="qstack.html#pop">pop</a>() and <a href="qstack.html#push">push</a>().</p> <!-- @@@top --> </div> </div> </div> </div> <div class="ft"> <span></span> </div> </div> <div class="footer"> <p> <acronym title="Copyright">©</acronym> 2015 The Qt Company Ltd. 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