gistfile1.php

<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');

class Const_class {
	
	protected static $data = array();

	public function __construct()
	{
		self::$data = array(
			// Any initial data
		);
	}
	
	// value getter
	public function __get($name)
	{
		if (array_key_exists($name, self::$data))
		{
			return self::$data[$name];
		}
		else
		{
			return null;
		}
	}
	
	// callback getter
	public function __call($name, $args)
	{
		if (array_key_exists($name, self::$data))
		{
			return call_user_func_array(self::$data[$name], $args);
		}
		else
		{
			return null;
		}
	}
	
	// value setter
	public function define($name, $value)
	{
		if (! array_key_exists($name, self::$data))
		{
			self::$data[$name] = $value;
		}
	}

}

class Const_holder {

	protected static $const = null;
	
	static function &get()
	{
		if (self::$const === null)
			self::$const = new Const_class;
		return self::$const;
	}
	
}

function &C() { return Const_holder::get(); }

/*
|--------------------------------------------------------------------------
| Demo Time !!! :D
|--------------------------------------------------------------------------
|
*/

// define some "constants"
C()->define('MY_CONST', 'MY_VALUE');
C()->define('MY_ARRAY', array(1, 2, 3, 4));
C()->define('MY_FUNC', function() { echo 'Hello World!'; });

// now read them
echo C()->MY_CONST;
print_r( C()->MY_ARRAY );
C()->MY_FUNC();


/* End of Gist */

I needed some more flexible "constants" ... :D