if !ok {
		return "", "", s, ErrHeader
	}

	// Parse the first token as a decimal integer.
	n, perr := strconv.ParseInt(nStr, 10, 0) // Intentionally parse as native int
	if perr != nil || n < 5 || n > int64(len(s)) {
		return "", "", s, ErrHeader
	}
	n -= int64(len(nStr) + 1) // convert from index in s to index in rest
	if n <= 0 {
		return "", "", s, ErrHeader
	}

	}
	var r io.Reader

	switch compType {
	case noneType:
		r = scannedReader
	case gzipType:
		gzr, err := gzip.NewReader(scannedReader)
		if err != nil {
			if errors.Is(err, gzip.ErrHeader) || errors.Is(err, gzip.ErrChecksum) {
				return nil, errInvalidCompression(err, compType)
			}
			return nil, errTruncatedInput(err)
		}
		r = gzr
		pr.closer = gzr
	case bzip2Type: