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<td >Qt 5.9</td><td ><a href="qtcore-index.html">Qt Core</a></td><td ><a href="qtcore-module.html">C++ Classes</a></td><td >QScopedPointer</td></tr></table><table class="buildversion"><tr>
<td id="buildversion" width="100%" align="right">Qt 5.9.4 Reference Documentation</td>
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<h3><a name="toc">Contents</a></h3>
<ul>
<li class="level1"><a href="#public-functions">Public Functions</a></li>
<li class="level1"><a href="#related-non-members">Related Non-Members</a></li>
<li class="level1"><a href="#details">Detailed Description</a></li>
<li class="level2"><a href="#custom-cleanup-handlers">Custom Cleanup Handlers</a></li>
<li class="level2"><a href="#forward-declared-pointers">Forward Declared Pointers</a></li>
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<h1 class="title">QScopedPointer Class</h1>
<!-- $$$QScopedPointer-brief -->
<p>The <a href="qscopedpointer.html">QScopedPointer</a> class stores a pointer to a dynamically allocated object, and deletes it upon destruction. <a href="#details">More...</a></p>
<!-- @@@QScopedPointer -->
<div class="table"><table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> Header:</td><td class="memItemRight bottomAlign">   <span class="preprocessor">#include &lt;QScopedPointer&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 4.6</td></tr><tr><td class="memItemLeft rightAlign topAlign"> Inherited By:</td><td class="memItemRight bottomAlign"> <p><a href="qscopedarraypointer.html">QScopedArrayPointer</a></p>
</td></tr></table></div><ul>
<li><a href="qscopedpointer-members.html">List of all members, including inherited members</a></li>
</ul>
<p><b>Note:</b> All functions in this class are reentrant.</p>
<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="qscopedpointer.html#QScopedPointer">QScopedPointer</a></b>(T *<i>p</i> = Q_NULLPTR)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qscopedpointer.html#dtor.QScopedPointer">~QScopedPointer</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> T *</td><td class="memItemRight bottomAlign"><b><a href="qscopedpointer.html#data">data</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qscopedpointer.html#isNull">isNull</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qscopedpointer.html#reset">reset</a></b>(T *<i>other</i> = Q_NULLPTR)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qscopedpointer.html#swap">swap</a></b>(QScopedPointer&lt;T, Cleanup&gt; &amp;<i>other</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> T *</td><td class="memItemRight bottomAlign"><b><a href="qscopedpointer.html#take">take</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qscopedpointer.html#operator-bool">operator bool</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qscopedpointer.html#operator-not">operator!</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> T &amp;</td><td class="memItemRight bottomAlign"><b><a href="qscopedpointer.html#operator-2a">operator*</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> T *</td><td class="memItemRight bottomAlign"><b><a href="qscopedpointer.html#operator--gt">operator-&gt;</a></b>() const</td></tr>
</table></div>
<a name="related-non-members"></a>
<h2 id="related-non-members">Related Non-Members</h2>
<div class="table"><table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qscopedpointer.html#operator-not-eq">operator!=</a></b>(const QScopedPointer&lt;T, Cleanup&gt; &amp;<i>lhs</i>, <i>std::nullptr_t</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qscopedpointer.html#operator-not-eq-1">operator!=</a></b>(<i>std::nullptr_t</i>, const QScopedPointer&lt;T, Cleanup&gt; &amp;<i>rhs</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qscopedpointer.html#operator-eq-eq">operator==</a></b>(const QScopedPointer&lt;T, Cleanup&gt; &amp;<i>lhs</i>, <i>std::nullptr_t</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qscopedpointer.html#operator-eq-eq-1">operator==</a></b>(<i>std::nullptr_t</i>, const QScopedPointer&lt;T, Cleanup&gt; &amp;<i>rhs</i>)</td></tr>
</table></div>
<a name="details"></a>
<!-- $$$QScopedPointer-description -->
<div class="descr">
<h2 id="details">Detailed Description</h2>
<p>The <a href="qscopedpointer.html">QScopedPointer</a> class stores a pointer to a dynamically allocated object, and deletes it upon destruction.</p>
<p>Managing heap allocated objects manually is hard and error prone, with the common result that code leaks memory and is hard to maintain. <a href="qscopedpointer.html">QScopedPointer</a> is a small utility class that heavily simplifies this by assigning stack-based memory ownership to heap allocations, more generally called resource acquisition is initialization(RAII).</p>
<p><a href="qscopedpointer.html">QScopedPointer</a> guarantees that the object pointed to will get deleted when the current scope disappears.</p>
<p>Consider this function which does heap allocations, and has various exit points:</p>
<pre class="cpp">

  <span class="type">void</span> myFunction(bool useSubClass)
  {
      MyClass <span class="operator">*</span>p <span class="operator">=</span> useSubClass <span class="operator">?</span> <span class="keyword">new</span> MyClass() : <span class="keyword">new</span> MySubClass;
      <span class="type"><a href="qiodevice.html">QIODevice</a></span> <span class="operator">*</span>device <span class="operator">=</span> handsOverOwnership();

      <span class="keyword">if</span> (m_value <span class="operator">&gt;</span> <span class="number">3</span>) {
          <span class="keyword">delete</span> p;
          <span class="keyword">delete</span> device;
          <span class="keyword">return</span>;
      }

      <span class="keyword">try</span> {
          process(device);
      }
      <span class="keyword">catch</span> (<span class="operator">.</span><span class="operator">.</span><span class="operator">.</span>) {
          <span class="keyword">delete</span> p;
          <span class="keyword">delete</span> device;
          <span class="keyword">throw</span>;
      }

      <span class="keyword">delete</span> p;
      <span class="keyword">delete</span> device;
  }

</pre>
<p>It's encumbered by the manual delete calls. With <a href="qscopedpointer.html">QScopedPointer</a>, the code can be simplified to:</p>
<pre class="cpp">

  <span class="type">void</span> myFunction(bool useSubClass)
  {
      <span class="comment">// assuming that MyClass has a virtual destructor</span>
      <span class="type"><a href="qscopedpointer.html#QScopedPointer">QScopedPointer</a></span><span class="operator">&lt;</span>MyClass<span class="operator">&gt;</span> p(useSubClass <span class="operator">?</span> <span class="keyword">new</span> MyClass() : <span class="keyword">new</span> MySubClass);
      <span class="type"><a href="qscopedpointer.html#QScopedPointer">QScopedPointer</a></span><span class="operator">&lt;</span><span class="type"><a href="qiodevice.html">QIODevice</a></span><span class="operator">&gt;</span> device(handsOverOwnership());

      <span class="keyword">if</span> (m_value <span class="operator">&gt;</span> <span class="number">3</span>)
          <span class="keyword">return</span>;

      process(device);
  }

</pre>
<p>The code the compiler generates for <a href="qscopedpointer.html">QScopedPointer</a> is the same as when writing it manually. Code that makes use of <i>delete</i> are candidates for <a href="qscopedpointer.html">QScopedPointer</a> usage (and if not, possibly another type of smart pointer such as <a href="qsharedpointer.html">QSharedPointer</a>). <a href="qscopedpointer.html">QScopedPointer</a> intentionally has no copy constructor or assignment operator, such that ownership and lifetime is clearly communicated.</p>
<p>The const qualification on a regular C++ pointer can also be expressed with a <a href="qscopedpointer.html">QScopedPointer</a>:</p>
<pre class="cpp">

      <span class="keyword">const</span> <span class="type"><a href="../qtwidgets/qwidget.html">QWidget</a></span> <span class="operator">*</span><span class="keyword">const</span> p <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="../qtwidgets/qwidget.html">QWidget</a></span>();
      <span class="comment">// is equivalent to:</span>
      <span class="keyword">const</span> <span class="type"><a href="qscopedpointer.html#QScopedPointer">QScopedPointer</a></span><span class="operator">&lt;</span><span class="keyword">const</span> <span class="type"><a href="../qtwidgets/qwidget.html">QWidget</a></span><span class="operator">&gt;</span> p(<span class="keyword">new</span> <span class="type"><a href="../qtwidgets/qwidget.html">QWidget</a></span>());

      <span class="type"><a href="../qtwidgets/qwidget.html">QWidget</a></span> <span class="operator">*</span><span class="keyword">const</span> p <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="../qtwidgets/qwidget.html">QWidget</a></span>();
      <span class="comment">// is equivalent to:</span>
      <span class="keyword">const</span> <span class="type"><a href="qscopedpointer.html#QScopedPointer">QScopedPointer</a></span><span class="operator">&lt;</span><span class="type"><a href="../qtwidgets/qwidget.html">QWidget</a></span><span class="operator">&gt;</span> p(<span class="keyword">new</span> <span class="type"><a href="../qtwidgets/qwidget.html">QWidget</a></span>());

      <span class="keyword">const</span> <span class="type"><a href="../qtwidgets/qwidget.html">QWidget</a></span> <span class="operator">*</span>p <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="../qtwidgets/qwidget.html">QWidget</a></span>();
      <span class="comment">// is equivalent to:</span>
      <span class="type"><a href="qscopedpointer.html#QScopedPointer">QScopedPointer</a></span><span class="operator">&lt;</span><span class="keyword">const</span> <span class="type"><a href="../qtwidgets/qwidget.html">QWidget</a></span><span class="operator">&gt;</span> p(<span class="keyword">new</span> <span class="type"><a href="../qtwidgets/qwidget.html">QWidget</a></span>());

</pre>
<a name="custom-cleanup-handlers"></a>
<h3 >Custom Cleanup Handlers</h3>
<p>Arrays as well as pointers that have been allocated with <code>malloc</code> must not be deleted using <code>delete</code>. <a href="qscopedpointer.html">QScopedPointer</a>'s second template parameter can be used for custom cleanup handlers.</p>
<p>The following custom cleanup handlers exist:</p>
<ul>
<li>QScopedPointerDeleter - the default, deletes the pointer using <code>delete</code></li>
<li>QScopedPointerArrayDeleter - deletes the pointer using <code>delete []</code>. Use this handler for pointers that were allocated with <code>new []</code>.</li>
<li>QScopedPointerPodDeleter - deletes the pointer using <code>free()</code>. Use this handler for pointers that were allocated with <code>malloc()</code>.</li>
<li>QScopedPointerDeleteLater - deletes a pointer by calling <code>deleteLater()</code> on it. Use this handler for pointers to <a href="qobject.html">QObject</a>'s that are actively participating in a <a href="qeventloop.html">QEventLoop</a>.</li>
</ul>
<p>You can pass your own classes as handlers, provided that they have a public static function <code>void cleanup(T *pointer)</code>.</p>
<pre class="cpp">

  <span class="comment">// this QScopedPointer deletes its data using the delete[] operator:</span>
  <span class="type"><a href="qscopedpointer.html#QScopedPointer">QScopedPointer</a></span><span class="operator">&lt;</span><span class="type">int</span><span class="operator">,</span> <span class="type">QScopedPointerArrayDeleter</span><span class="operator">&lt;</span><span class="type">int</span><span class="operator">&gt;</span> <span class="operator">&gt;</span> arrayPointer(<span class="keyword">new</span> <span class="type">int</span><span class="operator">[</span><span class="number">42</span><span class="operator">]</span>);

  <span class="comment">// this QScopedPointer frees its data using free():</span>
  <span class="type"><a href="qscopedpointer.html#QScopedPointer">QScopedPointer</a></span><span class="operator">&lt;</span><span class="type">int</span><span class="operator">,</span> <span class="type">QScopedPointerPodDeleter</span><span class="operator">&gt;</span> podPointer(<span class="keyword">reinterpret_cast</span><span class="operator">&lt;</span><span class="type">int</span> <span class="operator">*</span><span class="operator">&gt;</span>(malloc(<span class="number">42</span>)));

  <span class="comment">// this struct calls &quot;myCustomDeallocator&quot; to delete the pointer</span>
  <span class="keyword">struct</span> ScopedPointerCustomDeleter
  {
      <span class="keyword">static</span> <span class="keyword">inline</span> <span class="type">void</span> cleanup(MyCustomClass <span class="operator">*</span>pointer)
      {
          myCustomDeallocator(pointer);
      }
  };

  <span class="comment">// QScopedPointer using a custom deleter:</span>
  <span class="type"><a href="qscopedpointer.html#QScopedPointer">QScopedPointer</a></span><span class="operator">&lt;</span>MyCustomClass<span class="operator">,</span> ScopedPointerCustomDeleter<span class="operator">&gt;</span> customPointer(<span class="keyword">new</span> MyCustomClass);

</pre>
<a name="forward-declared-pointers"></a>
<h3 >Forward Declared Pointers</h3>
<p>Classes that are forward declared can be used within <a href="qscopedpointer.html">QScopedPointer</a>, as long as the destructor of the forward declared class is available whenever a <a href="qscopedpointer.html">QScopedPointer</a> needs to clean up.</p>
<p>Concretely, this means that all classes containing a <a href="qscopedpointer.html">QScopedPointer</a> that points to a forward declared class must have non-inline constructors, destructors and assignment operators:</p>
<pre class="cpp">

  <span class="keyword">class</span> MyPrivateClass; <span class="comment">// forward declare MyPrivateClass</span>

  <span class="keyword">class</span> MyClass
  {
  <span class="keyword">private</span>:
      <span class="type"><a href="qscopedpointer.html#QScopedPointer">QScopedPointer</a></span><span class="operator">&lt;</span>MyPrivateClass<span class="operator">&gt;</span> privatePtr; <span class="comment">// QScopedPointer to forward declared class</span>

  <span class="keyword">public</span>:
      MyClass(); <span class="comment">// OK</span>
      <span class="keyword">inline</span> <span class="operator">~</span>MyClass() {} <span class="comment">// VIOLATION - Destructor must not be inline</span>

  <span class="keyword">private</span>:
      Q_DISABLE_COPY(MyClass) <span class="comment">// OK - copy constructor and assignment operators</span>
                               <span class="comment">// are now disabled, so the compiler won't implicitely</span>
                               <span class="comment">// generate them.</span>
  };

</pre>
<p>Otherwise, the compiler outputs a warning about not being able to destruct <code>MyPrivateClass</code>.</p>
</div>
<p><b>See also </b><a href="qsharedpointer.html">QSharedPointer</a>.</p>
<!-- @@@QScopedPointer -->
<div class="func">
<h2>Member Function Documentation</h2>
<!-- $$$QScopedPointer[overload1]$$$QScopedPointerT* -->
<h3 class="fn" id="QScopedPointer"><a name="QScopedPointer"></a>QScopedPointer::<span class="name">QScopedPointer</span>(<span class="type">T</span> *<i>p</i> = Q_NULLPTR)</h3>
<p>Constructs this <a href="qscopedpointer.html">QScopedPointer</a> instance and sets its pointer to <i>p</i>.</p>
<!-- @@@QScopedPointer -->
<!-- $$$~QScopedPointer[overload1]$$$~QScopedPointer -->
<h3 class="fn" id="dtor.QScopedPointer"><a name="dtor.QScopedPointer"></a>QScopedPointer::<span class="name">~QScopedPointer</span>()</h3>
<p>Destroys this <a href="qscopedpointer.html">QScopedPointer</a> object. Delete the object its pointer points to.</p>
<!-- @@@~QScopedPointer -->
<!-- $$$data[overload1]$$$data -->
<h3 class="fn" id="data"><a name="data"></a><span class="type">T</span> *QScopedPointer::<span class="name">data</span>() const</h3>
<p>Returns the value of the pointer referenced by this object. <a href="qscopedpointer.html">QScopedPointer</a> still owns the object pointed to.</p>
<!-- @@@data -->
<!-- $$$isNull[overload1]$$$isNull -->
<h3 class="fn" id="isNull"><a name="isNull"></a><span class="type">bool</span> QScopedPointer::<span class="name">isNull</span>() const</h3>
<p>Returns <code>true</code> if this object is holding a pointer that is <code>null</code>.</p>
<!-- @@@isNull -->
<!-- $$$reset[overload1]$$$resetT* -->
<h3 class="fn" id="reset"><a name="reset"></a><span class="type">void</span> QScopedPointer::<span class="name">reset</span>(<span class="type">T</span> *<i>other</i> = Q_NULLPTR)</h3>
<p>Deletes the existing object it is pointing to if any, and sets its pointer to <i>other</i>. <a href="qscopedpointer.html">QScopedPointer</a> now owns <i>other</i> and will delete it in its destructor.</p>
<!-- @@@reset -->
<!-- $$$swap[overload1]$$$swapQScopedPointer<T,Cleanup>& -->
<h3 class="fn" id="swap"><a name="swap"></a><span class="type">void</span> QScopedPointer::<span class="name">swap</span>(<span class="type"><a href="qscopedpointer.html#QScopedPointer">QScopedPointer</a></span>&lt;<span class="type">T</span>, <span class="type">Cleanup</span>&gt; &amp;<i>other</i>)</h3>
<p>Swap this pointer with <i>other</i>.</p>
<!-- @@@swap -->
<!-- $$$take[overload1]$$$take -->
<h3 class="fn" id="take"><a name="take"></a><span class="type">T</span> *QScopedPointer::<span class="name">take</span>()</h3>
<p>Returns the value of the pointer referenced by this object. The pointer of this <a href="qscopedpointer.html">QScopedPointer</a> object will be reset to <code>null</code>.</p>
<p>Callers of this function take ownership of the pointer.</p>
<!-- @@@take -->
<!-- $$$operator bool[overload1]$$$operator bool -->
<h3 class="fn" id="operator-bool"><a name="operator-bool"></a>QScopedPointer::<span class="name">operator bool</span>() const</h3>
<p>Returns <code>true</code> if this object is not <code>null</code>. This function is suitable for use in <code>if-constructs</code>, like:</p>
<pre class="cpp">

  <span class="keyword">if</span> (scopedPointer) {
      <span class="operator">.</span><span class="operator">.</span><span class="operator">.</span>
  }

</pre>
<p><b>See also </b><a href="qscopedpointer.html#isNull">isNull</a>().</p>
<!-- @@@operator bool -->
<!-- $$$operator![overload1]$$$operator! -->
<h3 class="fn" id="operator-not"><a name="operator-not"></a><span class="type">bool</span> QScopedPointer::<span class="name">operator!</span>() const</h3>
<p>Returns <code>true</code> if the pointer referenced by this object is <code>null</code>, otherwise returns <code>false</code>.</p>
<p><b>See also </b><a href="qscopedpointer.html#isNull">isNull</a>().</p>
<!-- @@@operator! -->
<!-- $$$operator*[overload1]$$$operator* -->
<h3 class="fn" id="operator-2a"><a name="operator-2a"></a><span class="type">T</span> &amp;QScopedPointer::<span class="name">operator*</span>() const</h3>
<p>Provides access to the scoped pointer's object.</p>
<p>If the contained pointer is <code>null</code>, behavior is undefined.</p>
<p><b>See also </b><a href="qscopedpointer.html#isNull">isNull</a>().</p>
<!-- @@@operator* -->
<!-- $$$operator->[overload1]$$$operator-> -->
<h3 class="fn" id="operator--gt"><a name="operator--gt"></a><span class="type">T</span> *QScopedPointer::<span class="name">operator-&gt;</span>() const</h3>
<p>Provides access to the scoped pointer's object.</p>
<p>If the contained pointer is <code>null</code>, behavior is undefined.</p>
<p><b>See also </b><a href="qscopedpointer.html#isNull">isNull</a>().</p>
<!-- @@@operator-> -->
</div>
<div class="relnonmem">
<h2>Related Non-Members</h2>
<!-- $$$operator!=[overload1]$$$operator!=constQScopedPointer<T,Cleanup>&std::nullptr_t -->
<h3 class="fn" id="operator-not-eq"><a name="operator-not-eq"></a><span class="type">bool</span> <span class="name">operator!=</span>(const <span class="type"><a href="qscopedpointer.html#QScopedPointer">QScopedPointer</a></span>&lt;<span class="type">T</span>, <span class="type">Cleanup</span>&gt; &amp;<i>lhs</i>, <i>std::nullptr_t</i>)</h3>
<p>Returns <code>true</code> if the scoped pointer <i>lhs</i> is a valid (i.e&#x2e; a non-null) pointer.</p>
<p>This function was introduced in  Qt 5.8.</p>
<p><b>See also </b><a href="qscopedpointer.html#isNull">QScopedPointer::isNull</a>().</p>
<!-- @@@operator!= -->
<!-- $$$operator!=$$$operator!=std::nullptr_tconstQScopedPointer<T,Cleanup>& -->
<h3 class="fn" id="operator-not-eq-1"><a name="operator-not-eq-1"></a><span class="type">bool</span> <span class="name">operator!=</span>(<i>std::nullptr_t</i>, const <span class="type"><a href="qscopedpointer.html#QScopedPointer">QScopedPointer</a></span>&lt;<span class="type">T</span>, <span class="type">Cleanup</span>&gt; &amp;<i>rhs</i>)</h3>
<p>Returns <code>true</code> if the scoped pointer <i>rhs</i> is a valid (i.e&#x2e; a non-null) pointer.</p>
<p>This function was introduced in  Qt 5.8.</p>
<p><b>See also </b><a href="qscopedpointer.html#isNull">QScopedPointer::isNull</a>().</p>
<!-- @@@operator!= -->
<!-- $$$operator==[overload1]$$$operator==constQScopedPointer<T,Cleanup>&std::nullptr_t -->
<h3 class="fn" id="operator-eq-eq"><a name="operator-eq-eq"></a><span class="type">bool</span> <span class="name">operator==</span>(const <span class="type"><a href="qscopedpointer.html#QScopedPointer">QScopedPointer</a></span>&lt;<span class="type">T</span>, <span class="type">Cleanup</span>&gt; &amp;<i>lhs</i>, <i>std::nullptr_t</i>)</h3>
<p>Returns <code>true</code> if the scoped pointer <i>lhs</i> is a null pointer.</p>
<p>This function was introduced in  Qt 5.8.</p>
<p><b>See also </b><a href="qscopedpointer.html#isNull">QScopedPointer::isNull</a>().</p>
<!-- @@@operator== -->
<!-- $$$operator==$$$operator==std::nullptr_tconstQScopedPointer<T,Cleanup>& -->
<h3 class="fn" id="operator-eq-eq-1"><a name="operator-eq-eq-1"></a><span class="type">bool</span> <span class="name">operator==</span>(<i>std::nullptr_t</i>, const <span class="type"><a href="qscopedpointer.html#QScopedPointer">QScopedPointer</a></span>&lt;<span class="type">T</span>, <span class="type">Cleanup</span>&gt; &amp;<i>rhs</i>)</h3>
<p>Returns <code>true</code> if the scoped pointer <i>rhs</i> is a null pointer.</p>
<p>This function was introduced in  Qt 5.8.</p>
<p><b>See also </b><a href="qscopedpointer.html#isNull">QScopedPointer::isNull</a>().</p>
<!-- @@@operator== -->
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