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<td ><a href="../qtdoc/index.html">Qt 5.11</a></td><td ><a href="qtcore-index.html">Qt Core</a></td><td ><a href="qtcore-module.html">C++ Classes</a></td><td >const_iterator</td></tr></table><table class="buildversion"><tr>
<td id="buildversion" width="100%" align="right">Qt 5.11.2 Reference Documentation</td>
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<h3><a name="toc">Contents</a></h3>
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<li class="level1"><a href="#public-functions">Public Functions</a></li>
<li class="level1"><a href="#details">Detailed Description</a></li>
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<h1 class="title">const_iterator Class</h1>
<span class="small-subtitle">(<a href="qsequentialiterable-const-iterator.html">QSequentialIterable::const_iterator</a>)<br/></span>
<!-- $$$const_iterator-brief -->
<p>The <a href="qsequentialiterable-const-iterator.html">QSequentialIterable::const_iterator</a> allows iteration over a container in a <a href="qvariant.html">QVariant</a>. <a href="#details">More...</a></p>
<!-- @@@const_iterator -->
<div class="table"><table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> Header:</td><td class="memItemRight bottomAlign">   <span class="preprocessor">#include &lt;const_iterator&gt;</span>
</td></tr><tr><td class="memItemLeft rightAlign topAlign"> qmake:</td><td class="memItemRight bottomAlign"> QT += core</td></tr><tr><td class="memItemLeft rightAlign topAlign"> Since:</td><td class="memItemRight bottomAlign">  Qt 5.2</td></tr></table></div><ul>
<li><a href="qsequentialiterable-const-iterator-members.html">List of all members, including inherited members</a></li>
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<a name="public-functions"></a>
<h2 id="public-functions">Public Functions</h2>
<div class="table"><table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qsequentialiterable-const-iterator.html#const_iterator">const_iterator</a></b>(const const_iterator &amp;<i>other</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qsequentialiterable-const-iterator.html#dtor.const_iterator">~const_iterator</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qsequentialiterable-const-iterator.html#operator-not-eq">operator!=</a></b>(const const_iterator &amp;<i>other</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> const QVariant </td><td class="memItemRight bottomAlign"><b><a href="qsequentialiterable-const-iterator.html#operator-2a">operator*</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> const_iterator </td><td class="memItemRight bottomAlign"><b><a href="qsequentialiterable-const-iterator.html#operator-2b">operator+</a></b>(int <i>j</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> const_iterator &amp;</td><td class="memItemRight bottomAlign"><b><a href="qsequentialiterable-const-iterator.html#operator-2b-2b">operator++</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> const_iterator </td><td class="memItemRight bottomAlign"><b><a href="qsequentialiterable-const-iterator.html#operator-2b-2b-1">operator++</a></b>(<i>int</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> const_iterator &amp;</td><td class="memItemRight bottomAlign"><b><a href="qsequentialiterable-const-iterator.html#operator-2b-eq">operator+=</a></b>(int <i>j</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> const_iterator </td><td class="memItemRight bottomAlign"><b><a href="qsequentialiterable-const-iterator.html#operator-">operator-</a></b>(int <i>j</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> const_iterator &amp;</td><td class="memItemRight bottomAlign"><b><a href="qsequentialiterable-const-iterator.html#operator--">operator--</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> const_iterator </td><td class="memItemRight bottomAlign"><b><a href="qsequentialiterable-const-iterator.html#operator---1">operator--</a></b>(<i>int</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> const_iterator &amp;</td><td class="memItemRight bottomAlign"><b><a href="qsequentialiterable-const-iterator.html#operator--eq">operator-=</a></b>(int <i>j</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> const_iterator &amp;</td><td class="memItemRight bottomAlign"><b><a href="qsequentialiterable-const-iterator.html#operator-eq">operator=</a></b>(const const_iterator &amp;<i>other</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qsequentialiterable-const-iterator.html#operator-eq-eq">operator==</a></b>(const const_iterator &amp;<i>other</i>) const</td></tr>
</table></div>
<a name="details"></a>
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<div class="descr">
<h2 id="details">Detailed Description</h2>
<p>The <a href="qsequentialiterable-const-iterator.html">QSequentialIterable::const_iterator</a> allows iteration over a container in a <a href="qvariant.html">QVariant</a>.</p>
<p>A <a href="qsequentialiterable-const-iterator.html">QSequentialIterable::const_iterator</a> can only be created by a <a href="qsequentialiterable.html">QSequentialIterable</a> instance, and can be used in a way similar to other stl-style iterators.</p>
<pre class="cpp">

  <span class="type"><a href="qlist.html">QList</a></span><span class="operator">&lt;</span><span class="type">int</span><span class="operator">&gt;</span> intList <span class="operator">=</span> {<span class="number">7</span><span class="operator">,</span> <span class="number">11</span><span class="operator">,</span> <span class="number">42</span>};

  <span class="type"><a href="qvariant.html">QVariant</a></span> variant <span class="operator">=</span> <span class="type"><a href="qvariant.html">QVariant</a></span><span class="operator">::</span>fromValue(intList);
  <span class="keyword">if</span> (variant<span class="operator">.</span>canConvert<span class="operator">&lt;</span><span class="type"><a href="qvariant.html#QVariantList-typedef">QVariantList</a></span><span class="operator">&gt;</span>()) {
      <span class="type">QSequentialIterable</span> iterable <span class="operator">=</span> variant<span class="operator">.</span>value<span class="operator">&lt;</span><span class="type">QSequentialIterable</span><span class="operator">&gt;</span>();
      <span class="comment">// Can use foreach:</span>
      foreach (<span class="keyword">const</span> <span class="type"><a href="qvariant.html">QVariant</a></span> <span class="operator">&amp;</span>v<span class="operator">,</span> iterable) {
          <a href="qtglobal.html#qDebug">qDebug</a>() <span class="operator">&lt;</span><span class="operator">&lt;</span> v;
      }
      <span class="comment">// Can use C++11 range-for:</span>
      <span class="keyword">for</span> (<span class="keyword">const</span> <span class="type"><a href="qvariant.html">QVariant</a></span> <span class="operator">&amp;</span>v : iterable) {
          <a href="qtglobal.html#qDebug">qDebug</a>() <span class="operator">&lt;</span><span class="operator">&lt;</span> v;
      }
      <span class="comment">// Can use iterators:</span>
      <span class="type">QSequentialIterable</span><span class="operator">::</span>const_iterator it <span class="operator">=</span> iterable<span class="operator">.</span>begin();
      <span class="keyword">const</span> <span class="type">QSequentialIterable</span><span class="operator">::</span>const_iterator end <span class="operator">=</span> iterable<span class="operator">.</span>end();
      <span class="keyword">for</span> ( ; it <span class="operator">!</span><span class="operator">=</span> end; <span class="operator">+</span><span class="operator">+</span>it) {
          <a href="qtglobal.html#qDebug">qDebug</a>() <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="operator">*</span>it;
      }
  }

</pre>
</div>
<p><b>See also </b><a href="qsequentialiterable.html">QSequentialIterable</a>.</p>
<!-- @@@const_iterator -->
<div class="func">
<h2>Member Function Documentation</h2>
<!-- $$$const_iterator[overload1]$$$const_iteratorconstconst_iterator& -->
<h3 class="fn" id="const_iterator"><a name="const_iterator"></a>const_iterator::<span class="name">const_iterator</span>(const <span class="type"><a href="qsequentialiterable-const-iterator.html#const_iterator">const_iterator</a></span> &amp;<i>other</i>)</h3>
<p>Creates a copy of <i>other</i>.</p>
<!-- @@@const_iterator -->
<!-- $$$~const_iterator[overload1]$$$~const_iterator -->
<h3 class="fn" id="dtor.const_iterator"><a name="dtor.const_iterator"></a>const_iterator::<span class="name">~const_iterator</span>()</h3>
<p>Destroys the <a href="qsequentialiterable-const-iterator.html">QSequentialIterable::const_iterator</a>.</p>
<!-- @@@~const_iterator -->
<!-- $$$operator!=[overload1]$$$operator!=constconst_iterator& -->
<h3 class="fn" id="operator-not-eq"><a name="operator-not-eq"></a><span class="type">bool</span> const_iterator::<span class="name">operator!=</span>(const <span class="type"><a href="qsequentialiterable-const-iterator.html#const_iterator">const_iterator</a></span> &amp;<i>other</i>) const</h3>
<p>Returns <code>true</code> if <i>other</i> points to a different item than this iterator; otherwise returns <code>false</code>.</p>
<p><b>See also </b><a href="qsequentialiterable-const-iterator.html#operator-eq-eq">operator==</a>().</p>
<!-- @@@operator!= -->
<!-- $$$operator*[overload1]$$$operator* -->
<h3 class="fn" id="operator-2a"><a name="operator-2a"></a>const <span class="type"><a href="qvariant.html">QVariant</a></span> const_iterator::<span class="name">operator*</span>() const</h3>
<p>Returns the current item, converted to a <a href="qvariant.html">QVariant</a>.</p>
<!-- @@@operator* -->
<!-- $$$operator+[overload1]$$$operator+int -->
<h3 class="fn" id="operator-2b"><a name="operator-2b"></a><span class="type"><a href="qsequentialiterable-const-iterator.html#const_iterator">const_iterator</a></span> const_iterator::<span class="name">operator+</span>(<span class="type">int</span> <i>j</i>) const</h3>
<p>Returns an iterator to the item at <i>j</i> positions forward from this iterator.</p>
<p><b>See also </b><a href="qsequentialiterable-const-iterator.html#operator-">operator-</a>() and <a href="qsequentialiterable-const-iterator.html#operator-2b-eq">operator+=</a>().</p>
<!-- @@@operator+ -->
<!-- $$$operator++[overload1]$$$operator++ -->
<h3 class="fn" id="operator-2b-2b"><a name="operator-2b-2b"></a><span class="type"><a href="qsequentialiterable-const-iterator.html#const_iterator">const_iterator</a></span> &amp;const_iterator::<span class="name">operator++</span>()</h3>
<p>The prefix ++ operator (<code>++it</code>) advances the iterator to the next item in the container and returns an iterator to the new current item.</p>
<p>Calling this function on <a href="qsequentialiterable.html#end">QSequentialIterable::end</a>() leads to undefined results.</p>
<p><b>See also </b><a href="qsequentialiterable-const-iterator.html#operator--">operator--</a>().</p>
<!-- @@@operator++ -->
<!-- $$$operator++$$$operator++int -->
<h3 class="fn" id="operator-2b-2b-1"><a name="operator-2b-2b-1"></a><span class="type"><a href="qsequentialiterable-const-iterator.html#const_iterator">const_iterator</a></span> const_iterator::<span class="name">operator++</span>(<i>int</i>)</h3>
<p>This is an overloaded function.</p>
<p>The postfix ++ operator (<code>it++</code>) advances the iterator to the next item in the container and returns an iterator to the previously current item.</p>
<!-- @@@operator++ -->
<!-- $$$operator+=[overload1]$$$operator+=int -->
<h3 class="fn" id="operator-2b-eq"><a name="operator-2b-eq"></a><span class="type"><a href="qsequentialiterable-const-iterator.html#const_iterator">const_iterator</a></span> &amp;const_iterator::<span class="name">operator+=</span>(<span class="type">int</span> <i>j</i>)</h3>
<p>Advances the iterator by <i>j</i> items.</p>
<p><b>See also </b><a href="qsequentialiterable-const-iterator.html#operator--eq">operator-=</a>() and <a href="qsequentialiterable-const-iterator.html#operator-2b">operator+</a>().</p>
<!-- @@@operator+= -->
<!-- $$$operator-[overload1]$$$operator-int -->
<h3 class="fn" id="operator-"><a name="operator-"></a><span class="type"><a href="qsequentialiterable-const-iterator.html#const_iterator">const_iterator</a></span> const_iterator::<span class="name">operator-</span>(<span class="type">int</span> <i>j</i>) const</h3>
<p>Returns an iterator to the item at <i>j</i> positions backward from this iterator.</p>
<p>If the container in the <a href="qvariant.html">QVariant</a> does not support bi-directional iteration, calling this function leads to undefined results.</p>
<p><b>See also </b><a href="qsequentialiterable-const-iterator.html#operator-2b">operator+</a>(), <a href="qsequentialiterable-const-iterator.html#operator--eq">operator-=</a>(), and <a href="qsequentialiterable.html#canReverseIterate">canReverseIterate</a>().</p>
<!-- @@@operator- -->
<!-- $$$operator--[overload1]$$$operator-- -->
<h3 class="fn" id="operator--"><a name="operator--"></a><span class="type"><a href="qsequentialiterable-const-iterator.html#const_iterator">const_iterator</a></span> &amp;const_iterator::<span class="name">operator--</span>()</h3>
<p>The prefix -- operator (<code>--it</code>) makes the preceding item current and returns an iterator to the new current item.</p>
<p>Calling this function on <a href="qsequentialiterable.html#begin">QSequentialIterable::begin</a>() leads to undefined results.</p>
<p>If the container in the <a href="qvariant.html">QVariant</a> does not support bi-directional iteration, calling this function leads to undefined results.</p>
<p><b>See also </b><a href="qsequentialiterable-const-iterator.html#operator-2b-2b">operator++</a>() and <a href="qsequentialiterable.html#canReverseIterate">canReverseIterate</a>().</p>
<!-- @@@operator-- -->
<!-- $$$operator--$$$operator--int -->
<h3 class="fn" id="operator---1"><a name="operator---1"></a><span class="type"><a href="qsequentialiterable-const-iterator.html#const_iterator">const_iterator</a></span> const_iterator::<span class="name">operator--</span>(<i>int</i>)</h3>
<p>This is an overloaded function.</p>
<p>The postfix -- operator (<code>it--</code>) makes the preceding item current and returns an iterator to the previously current item.</p>
<p>If the container in the <a href="qvariant.html">QVariant</a> does not support bi-directional iteration, calling this function leads to undefined results.</p>
<p><b>See also </b><a href="qsequentialiterable.html#canReverseIterate">canReverseIterate</a>().</p>
<!-- @@@operator-- -->
<!-- $$$operator-=[overload1]$$$operator-=int -->
<h3 class="fn" id="operator--eq"><a name="operator--eq"></a><span class="type"><a href="qsequentialiterable-const-iterator.html#const_iterator">const_iterator</a></span> &amp;const_iterator::<span class="name">operator-=</span>(<span class="type">int</span> <i>j</i>)</h3>
<p>Makes the iterator go back by <i>j</i> items.</p>
<p>If the container in the <a href="qvariant.html">QVariant</a> does not support bi-directional iteration, calling this function leads to undefined results.</p>
<p><b>See also </b><a href="qsequentialiterable-const-iterator.html#operator-2b-eq">operator+=</a>(), <a href="qsequentialiterable-const-iterator.html#operator-">operator-</a>(), and <a href="qsequentialiterable.html#canReverseIterate">canReverseIterate</a>().</p>
<!-- @@@operator-= -->
<!-- $$$operator=[overload1]$$$operator=constconst_iterator& -->
<h3 class="fn" id="operator-eq"><a name="operator-eq"></a><span class="type"><a href="qsequentialiterable-const-iterator.html#const_iterator">const_iterator</a></span> &amp;const_iterator::<span class="name">operator=</span>(const <span class="type"><a href="qsequentialiterable-const-iterator.html#const_iterator">const_iterator</a></span> &amp;<i>other</i>)</h3>
<p>Assigns <i>other</i> to this.</p>
<!-- @@@operator= -->
<!-- $$$operator==[overload1]$$$operator==constconst_iterator& -->
<h3 class="fn" id="operator-eq-eq"><a name="operator-eq-eq"></a><span class="type">bool</span> const_iterator::<span class="name">operator==</span>(const <span class="type"><a href="qsequentialiterable-const-iterator.html#const_iterator">const_iterator</a></span> &amp;<i>other</i>) const</h3>
<p>Returns <code>true</code> if <i>other</i> points to the same item as this iterator; otherwise returns <code>false</code>.</p>
<p><b>See also </b><a href="qsequentialiterable-const-iterator.html#operator-not-eq">operator!=</a>().</p>
<!-- @@@operator== -->
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