title: Codeigniter Cannot redeclare class Hierarchy
body: <p>I have some problems with some Hierarchy classes in Codeigniter. I have a 3 level hierarchy on controller:</p>
  
  <pre><code>class Application_controller extends CI_Controller
  </code></pre>
  
  <p>Another one,</p>
  
  <pre><code>class Newsletter extends Application_controller
  </code></pre>
  
  <p>and the third one:</p>
  
  <pre><code>class Groups extends Newsletter
  </code></pre>
  
  <p>I have some constants defined in the classes for configuration to make the code more clean and easy to integrate with other models.</p>
  
  <p>The problem is when i try to access the menu to make a newsletter and send it to some clients i try to do this:</p>
  
  <pre><code>function createNewsletter(){
  Groups::TABLE;
  }
  </code></pre>
  
  <p>in that variable i have the table name to get the groups from database. Buit keeps me showing this error:</p>
  
  <blockquote>
    <p>Cannot redeclare class</p>
  </blockquote>
  
  <p>I have the require_once in the Classes like usual but it keeps me showing that error.
  Can you help me?</p>
  
  <p>Thanks in advance,</p>
  
  <p>Elkas</p>