system/HTTP/URI.php
public function keepQuery(...$params)
	{
		$temp = [];

		foreach ($this->query as $key => $value)
		{
			if (! in_array($key, $params))
			{
				continue;
			}

			$temp[$key] = $value;
		}

		$this->query = $temp;

		return $this;
	}
public function keepQuery(...$params)
	{
		$temp = [];

		foreach ($this->query as $key => $value)
		{
			if (! in_array($key, $params))
			{
				continue;
			}

			$temp[$key] = $value;
		}

		$this->query = $temp;

		return $this;
	}
Filters the query variables so that only the keys passed in
are kept. The rest are removed from the object.

@param array ...$params

@return $this