parseField :: PB.Parser (Text,Text)
parseField = tuplate pack <$> keyValue
  where
    keyValue   = (,) <$> (fieldKey   <* char ':' <* space)
                     <*> (fieldValue <* newline)
    fieldKey   = (:) <$> letter <*> many fieldChar
    fieldChar  = letter <|> digit <|> oneOf "-_"
    fieldValue = (:) <$> letter <*> many (noneOf "\n")