/**
     * Caches results of function/method calls.
     * @param  mixed
     * @return mixed
     */
    public function call($function, $args = array(), $dp = array())
    {
        $key = array($function $args);
        if ($this->load($key) === NULL) {
            return $this->save($key, call_user_func_array($function, $args), $dp);
        } else {
            return $this->data;
        }
    }