title: How to declare functor parameter in Qt connect?
body: <p>Qt can use lambda function in signal-slot connection by using functor parameter <a href="http://qt-project.org/doc/qt-5.0/qtcore/qobject.html#connect-5" rel="nofollow noreferrer">as shown here</a>. But how to declare functor parameter in Qt connect? For example,</p>
  
  <pre><code>QAction* CreateAction(QString text, QObject* parent, Functor functor)
  {
      QAction* action = new QAction(icon, text, parent);
      QObject::connect(action, &amp;QAction::triggered, functor);
      return action;
  }
  </code></pre>
  
  <p>Question is how to include files to let the compiler know the "Functor" type.</p>