title: Cast javascript object to array. How to?
body: <p>I have made this sandbox test:</p>
  
  <pre><code>&lt;html&gt;
      &lt;head&gt;
          &lt;title&gt;whatever&lt;/title&gt;
          &lt;script type="text/javascript"&gt;
              function myLittleTest() {
                  var obj, arr, armap;
  
                  arr = [1, 2, 3, 5, 7, 11];
  
                  obj = {};
                  obj = arr;
                  alert (typeof arr);
                  alert (typeof obj);
  
                  // doesn't work in IE
                  armap = obj.map(function (x) { return x * x; });
                  alert (typeof armap);
  
              }
              myLittleTest();
          &lt;/script&gt;
      &lt;/head&gt;
      &lt;body&gt;
      &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  
  <p>I realize I can use jQuery's function $.map for making that line of code work, but, what am I missing on javascript datatypes?</p>