class Result extends \lithium\data\source\Result {

	/**
	 * Fetches the next result from the resource.
	 *
	 * @return array|boolean|null Returns a key/value pair for the next result,
	 *         `null` if there is none, `false` if something bad happened.
	 */
	protected function _fetch() {
		if (!$this->_resource) {
			return false;
		}
		if (!$this->_resource->hasNext()) {
			return null;
		}
		$result = $this->_resource->getNext();

		if ($result instanceof MongoGridFSFile) {
			$result = array('file' => $result) + $result->file;
		}
		return array($this->_iterator, $result);
	}
}