public static function lines(string ...$lines): string
    {
        $head = true;
        return join(
                '',
                array_map(
                        function($line) use (&$head)
                        {
                            if (empty($line) && $head) {
                                $head = false;
                                return self::emptyLine();
                            }

                            if ($head) {
                                return self::line($line);
                            }

                            return $line;
                        },
                        $lines
                )
        );
    }