public function isEmptyAt($index)
    {
        $token = $this[$index];

        return null === $token->getId() && '' === $token->getContent();
    }
public function isEmptyAt($index)
    {
        $token = $this[$index];

        return null === $token->getId() && '' === $token->getContent();
    }
@param int $index

@return bool