title: switch(!0) What does it mean
body: <p>I saw a piece of code that stuck me as odd.
  What does switch(!0) mean in javascript? What are some cases where this technique would be useful to use?</p>
  
  <p>jsTree uses it in a few places but it looks foreign. I'm sure it has a good reason behind it, but can't figure it out.</p>
  
  <p><a href="http://www.jstree.com/">http://www.jstree.com/</a></p>
  
  <p>Here is a clip of code:</p>
  
  <pre><code>switch(!0) {
      case (!s.data &amp;&amp; !s.ajax): throw "Neither data nor ajax settings supplied.";
      case ($.isFunction(s.data)): //...
                                   break;
  }
  </code></pre>