title: C++ QList in if statement, what is default value?
body: <p>I find some code sample with these oddl lines</p>
  
  <pre><code>QList&lt;TDataXml *&gt; *newXMLData = input-&gt;getValue&lt;QList&lt;TDataXml *&gt;&gt;();
      if(newXMLData) 
      {
          // do things
      }
  </code></pre>
  
  <p>I dont understand <code>if(newXMLData)</code>. This is a QList. When should statement be true or false? Why not use Qt isEmpty() method instead?</p>
  
  <p>Thanks </p>