title: why parseJSON returns null
body: <p>I have following jQuery/JS code</p>
  
  <pre><code>&lt;script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4/jquery.min.js"&gt;&lt;/script&gt;
  &lt;script&gt;
    $.getJSON("http://example/topics", {}, function(data){
             console.log( data ); // display the JSON *data* in the web console
             console.log( $.parseJSON(data) );
    });
  &lt;/script&gt;
  </code></pre>
  
  <p><strong>console.log(data)</strong> shows JSON data within firebug console (firefox add-on), but <strong>console.log( $.parseJSON(data) )</strong> shows <strong>null</strong>.</p>
  
  <p>what could be possible reason.</p>
  
  <p>I need to convert JSON string into array.</p>