Parser::getLinesGenerator

private function getLinesGenerator(): ?Generator
{
	$tmp = explode("rn", $this->content);

	for ($i = 0, $length = count($tmp); $i < $length; $i++)
	{
		$line = rtrim($tmp[$i]);

		while (isset($tmp[$i + 1]) && mb_strlen($tmp[$i + 1]) > 0 && ($tmp[$i + 1][0] === ' ' || $tmp[$i + 1][0] === "t" ))
		{
			$line .= rtrim(mb_substr($tmp[++$i],1));
		}

		yield $line;
	}

	return null;
}