title: Append script in head by jquery
body: <p>I want append <code>script</code> in head if there is tag <code>&lt;script&gt;</code> in the body, i try as following but it don't work, How can done it?</p>
  
  <p><strong>DEMO:</strong> <a href="http://jsfiddle.net/rYXJx/" rel="nofollow">http://jsfiddle.net/rYXJx/</a></p>
  
  <p>JS:</p>
  
  <pre><code>var TAREA = $('body').find('textarea').length;
  
  if(TAREA &gt; 0){ 
      $('head').append('&lt;script type="text/javascript" src="files/js/nicEdit.js"&gt;&lt;/script&gt;&lt;script type="text/javascript"&gt;bkLib.onDomLoaded(function() { nicEditors.allTextAreas() });&lt;/script&gt;');
      };
  </code></pre>