How to define a global variable(value) in codeIgniter

Question

I simply do not mean how to define a global variable/constant in CodeIgniter. Let me explain: I have made a theme engine which is select-able from the current logged in user\'s

Answer 1

In Codeigniter all constant is defined inside application/config/constant.php.
like: define("CONSTANTNAME","value");

Constant degined here is accessible throughout all pages, ie; controllers, models and views