title: Undefined property: Session::$session
body: <p>Setting data not working ? Where's my problem?
  I load library only in this controller for practice but I'm receiving this error.</p>
  <blockquote>
  <p>A PHP Error was encountered</p>
  <p>Message: Undefined property: Session::$session</p>
  </blockquote>
  <pre><code>&lt;?php 
  
  class Session extends CI_Controller {
      
      public function __construct() {
          parent::__construct();
          $this-&gt;load-&gt;library('session');
      }
      
      public function index() {
                  
          $newdata = array(
                  'username'  =&gt; 'johndoe',
                  'email'     =&gt; 'johndoe@some-site.com',
                  'logged_in' =&gt; TRUE
          );
          $this-&gt;session-&gt;set_userdata($newdata);
          
      }
  
  }
  </code></pre>