title: Is it possible to connect a signal to a static slot without a receiver instance?
body: <p>Is it possible to connect a signal to static slot without receiver instance?</p>
  
  <p>Like this: <code>connect(&amp;object, SIGNAL(some()), STATIC_SLOT(staticFooMember()));</code></p>
  
  <p>There is a <code>QApplication::closeAllWindows()</code> function with [static slot] attribute in Qt documentation. And there is an example of using it from the documentation:</p>
  
  <pre><code>exitAct = new QAction(tr("E&amp;xit"), this);
  exitAct-&gt;setShortcuts(QKeySequence::Quit);
  exitAct-&gt;setStatusTip(tr("Exit the application"));
  connect(exitAct, SIGNAL(triggered()), qApp, SLOT(closeAllWindows()));
  </code></pre>
  
  <p>Is it allowed to do the same action but without passing an instance variable (e.g. when a class has only static functions)?</p>
  
  <pre><code>class Some : public QObject {
      Q_OBJECT
  public slots:
      static void foo();
  private:
      Some();
  };
  </code></pre>
  
  <hr>
  
  <p>Maybe Frank Osterfeld is right and it is better to use singleton pattern in this case but I am still surprised why this feature has not been implemented yet.</p>
  
  <p><strong>Update:</strong></p>
  
  <p><a href="http://woboq.com/blog/new-signals-slots-syntax-in-qt5.html" rel="noreferrer">In Qt 5 it is possible</a>.</p>