title: jQuery empty() callback not being fired
body: <p>I'm emptying an element of all children, then applying an element with the same class but within separate element.</p>
  
  <p>The callback on this <code>empty()</code> function isn't firing. Am I missing something with this class/callback issue?</p>
  
  <pre><code>$('.commentsButton').click(function(e){
  e.preventDefault();
  if ('.openComments').length) {
      $(this).closest('.box').removeClass(openComments);
  
      $('.commentsBox').empty(function(){
              $(this).closest('.box').find('.commentsBox').load('url.com');
              $(this).closest('.box').addClass(openComments);
          });
  } else {
          $(this).closest('.box').find('.commentsBox').load('url.com');
          $(this).closest('.box').addClass(openComments);
      }
  });
  
  &lt;div class="box"&gt;
    &lt;a class="commentsButton" href="#"&gt;&lt;/a&gt;
     &lt;div class="commentsBox"&gt;&lt;/div&gt;
  &lt;/div&gt;
  &lt;div class="box"&gt;
    &lt;a class="commentsButton" href="#"&gt;&lt;/a&gt;
     &lt;div class="commentsBox"&gt;&lt;/div&gt;
  &lt;/div&gt;
  </code></pre>