title: Difference between #selector(Aclass.method) and #selector(self.method)
body: <p>What is the difference between:</p>
  
  <p><code>#selector(Aclass.someMethod)</code> and <code>#selector(self.someMethod)</code></p>
  
  <p><code>someMethod</code> is an instance function and I'm calling inside <code>AClass</code> like this:</p>
  
  <pre><code>NSNotificationCenter.defaultCenter().addObserver(self, 
    selector: #selector(self.someMethod), // #selector(Aclass.method)
    name: "REMoveOrderViewRefresh", 
    object: nil
  )
  </code></pre>