title: how to define global constants in codeigniter in constants.php
body: <p>I have stored my global constants in config->constants.php but it creating problem and throwing error
  I have defined it like this, how to call it in controller,
  <strong>code</strong></p>
  
  <pre><code>define('SuperAdmin','1');
  define('Admin','2');
  define('CityAdmin' '3');
  define('SupportAdmin','4');
  define('RestaurantUser','5');
  define('FrontUser','6');
  define('Other','7');
  </code></pre>