title: Attempt at understanding the double-dispatch pattern
body: <p>I've been trying to grok the <a href="http://en.wikipedia.org/wiki/Double_dispatch" rel="noreferrer">double-dispatch pattern</a> and having a hard time. I finally attempted a sample program to help myself understand. <a href="https://gist.github.com/udit99/5323252" rel="noreferrer">Here's</a> the gist. But then I decided to attempt it <a href="https://gist.github.com/udit99/5323268" rel="noreferrer">without Double dispatch</a> and the solution didn't look any more terrible than usual. What am I doing wrong?</p>
  
  <p>Edit: as per suggestion, I've posted this question <a href="https://softwareengineering.stackexchange.com/questions/194082/attempt-at-understanding-the-double-dispatch-pattern">here</a>. Keeping this link around for redirects. </p>