public function join($glue, $finalGlue = '')
    {
        if ($finalGlue === '') {
            return $this->implode($glue);
        }

        $count = $this->count();

        if ($count === 0) {
            return '';
        }

        if ($count === 1) {
            return $this->last();
        }

        $collection = new static($this->items);

        $finalItem = $collection->pop();

        return $collection->implode($glue).$finalGlue.$finalItem;
    }