src/Primitive/Container/Container.php
protected function forgetRecursive($forgetKey, $items)
    {
        Arr::forget($items, $forgetKey);

        foreach ($items as $key => $item)
        {
            if ($this->isArrayable($item))
            {
                $items[$key] = $this->forgetRecursive($forgetKey, $this->retrieveValue($item));
            }
        }

        return $items;
    }
protected function forgetRecursive($forgetKey, $items)
    {
        Arr::forget($items, $forgetKey);

        foreach ($items as $key => $item)
        {
            if ($this->isArrayable($item))
            {
                $items[$key] = $this->forgetRecursive($forgetKey, $this->retrieveValue($item));
            }
        }

        return $items;
    }
Recursive unset.

@param $forgetKey
@param mixed $items
@return mixed