Parsec

CSVParse.hs

module CSVParse (parseCSV) where

import           Text.ParserCombinators.Parsec

-- verbose version
-- csvFile :: GenParser Char st [[String]]
-- csvFile = do
--     do result <- many line
--        eof
--        return result

-- line :: GenParser Char st [String]
-- line = do
--     do result <- cells
--        eol
--        return result

-- cells :: GenParser Char st [String]
-- cells =
--     do first <- cellContent
--        next <- remainingCells
--        return (first : next)

-- cellContent :: GenParser Char st String
-- cellContent =
--     many (noneOf ",\n")

-- remainingCells :: GenParser Char st [String]
-- remainingCells = do
--     (char ',' >> cells)
--     <|> (return [])

-- -- eol :: GenParser Char st Char
-- -- eol = char '\n'

eol = char '\n' >> (return ())
csvFile = endBy line eol
line = sepBy cell (char ',')
cell = many (noneOf ",\n")

parseCSV :: String -> Either ParseError [[String]]
parseCSV = parse csvFile "(unknown)"

FormParse.hs

module FormParse where

import           Numeric                       (readHex)
import           Text.ParserCombinators.Parsec

p_query :: CharParser () [(String, Maybe String)]
p_query = p_pair `sepBy` char '&'

p_pair :: CharParser () (String, Maybe String)
p_pair = do
    name <- many1 p_char
    value <- optionMaybe (char '=' >> many p_char)
    return (name, value)

p_char :: CharParser () Char
p_char = oneOf urlBaseChars
    <|> (char '+' >> return ' ')
    <|> p_hex

urlBaseChars = ['a'..'z']++['A'..'Z']++['0'..'9']++"$-_.!*'(),"

p_hex :: CharParser () Char
p_hex = do
    char '%'
    a <- hexDigit
    b <- hexDigit
    let ((d, _):_) = readHex [a,b]
    return . toEnum $ d


parseUrlQuery = parse p_query "(unknown)"