title: What is the variable $x used for in Chrome?
body: <p>A few days ago a friend and I were playing around with the Javascript console in Chrome (using a slightly older version, but this can be repeated in the latest stable build on both OSX and windows) when we assigned a string to the variable $x.</p>
  
  <pre><code>$x = "hello"
  </code></pre>
  
  <p>but when we echo out the value of $x, we get given the following code in the console:</p>
  
  <pre><code>bound: function (xpath, context)
  {
      var doc = (context &amp;&amp; context.ownerDocument) || inspectedWindow.document;
      var result = doc.evaluate(xpath, context || doc, null, XPathResult.ANY_TYPE, null);
      switch (result.resultType) {
      case XPathResult.NUMBER_TYPE:
          return result.numberValue;
      case XPathResult.STRING_TYPE:
          return result.stringValue;
      case XPathResult.BOOLEAN_TYPE:
          return result.booleanValue;
      default:
          var nodes = [];
          var node;
          while (node = result.iterateNext())
              nodes.push(node);
          return nodes;
      }
  }
  </code></pre>
  
  <p>We got a similar output in stable versions of Safari and Firefox. As far as we can tell, the $x variable is not attached to the global window object. </p>
  
  <p>What is $x, and what's it used for?</p>