public function getExtends($short = false)
    {
        $extends = '';
        if ($this->isArray()) {
            $extends = $this->getGenerator()->getOptionStructArrayClass();
        } elseif (!$this->isRestriction()) {
            $extends = $this->getGenerator()->getOptionStructClass();
        }
        return $short ? Utils::removeNamespace($extends) : $extends;
    }