title: object that called for the eventListener
body: <p>The situation is I need to access the object that called for the eventListener</p>
  
  <p>for example: 
  if i'm adding: <code>balls[ball]:addEventListener( "collision", removeBricks)</code> how can i access <code>balls[ball]</code> in removeBricks function?</p>
  
  <pre><code>function removeBricks(event)
      print("caller: " .. balls[ball])
      ...
  end
  balls[ball]:addEventListener( "collision", removeBricks)
  </code></pre>
  
  <p>what i've tried:</p>
  
  <pre><code>balls["ball"]:addEventListener( "collision", removeBricks(event, balls["ball"]))                
  </code></pre>