requestLine =
    (,,) <$>
    (method <* B.skipSpace) <*>
    (B.takeTill B.isSpace <* B.skipSpace) <*>
    httpVersion
  where method = "GET" <|> "POST"

httpVersion = "HTTP/" *> ((,) <$> (int <* B.char '.') <*> int)

responseLine = (,,) <$>
               (httpVersion <* B.skipSpace) <*>
               (int <* B.skipSpace) <*>
               bodyLine