Crater voice 纠错：保存发票时候，出现 preg_grep: Unknown modifier “a”

    public function isGuarded($key)
    {
        if (empty($this->getGuarded())) {
            return false;
        }
        return $this->getGuarded() == ['*'] ||
               ! empty(preg_grep('/^'.str_replace('/','\/',preg_quote($key)).'$$
               ! $this->isGuardableColumn($key);
    }