title: What does call.call accomplish in javascript
body: <p>Found this excerpt in the Modernizr source code.  </p>
  
  <pre><code>var documentCreateElement = scopeDocument.createElement, documentCreateDocumentFragment = scopeDocument.createDocumentFragment;
  
  // shiv the document
  for (var i = 0, elements = html5.elements, l = elements.length; i &lt; l; ++i) {
       call.call(documentCreateElement, scopeDocument, elements[i]);
  }
  
  // shiv the document create element method
  scopeDocument.createElement = function (nodeName) {
  var element = call.call(documentCreateElement, scopeDocument, nodeName);
  </code></pre>
  
  <p>I was wondering why it was necessary to use <code>call.call</code>, as opposed to just <code>call</code> What is the accomplishing that <code>documentCreateElement.call(scopeDocument,nodeName)</code> does not? </p>
  
  <p>Thanks in advance</p>