public function interpretAttribute($attribute, $index = null)
    {
        if ($index) {
            $availables = $this->getInterpretations();

            if (isset($availables[$index])) {
                return $availables[$index]->{$attribute};
            }
        }

        $current = $this->getCurrentInterpretation();

        if ($current) {
            return $current->{$attribute};
        }

        return null;
    }