return err
			}
			buf.Write(blk[:])
			for _, c := range blk {
				if c == '\n' {
					cntNewline++
				}
			}
		}
		return nil
	}

	// nextToken gets the next token delimited by a newline. This assumes that
	// at least one newline exists in the buffer.
	nextToken := func() string {
		cntNewline--
		tok, _ := buf.ReadString('\n')
		return strings.TrimRight(tok, "\n")
	}