browsergame/libs/SessionWrapper.php

<?php
class SessionWrapper {
	public function set($key, $value) {
		$_SESSION[$key] = $value;
	}
	public function get($key) {
		return $_SESSION[$key];
	}
	public function getDefault($key, $default) {
		return isset($_SESSION[$key]) ? $_SESSION[$key] : $default;
	}
	public function unsetKey($key) {
		unset($_SESSION[$key]);
	}
}