title: Fatal error: Using $this when not in object context in E:\xampp\htdocs\
body: <p>I am getting a Fatal Error while calling a public method using Scope Resolution Operator. Here is the part of the code:</p>
  
  <pre><code>Class userrole {
      public function get_premium_subscritpion($userID) {
          $userID = ($userID == '') ? $this-&gt;user_info-&gt;ID : $userID;
          if (empty($userID)) return false;
  
          /* Check if user has subscribed */
          if ($this-&gt;get_subscription($userID) &amp;&amp; $userID != '') {
              return true;
          }
      }
  }
  
  $role = userrole::get_premium_subscritpion(1);
  </code></pre>