gistfile1.hs

import Data.List

infinityString st = st ++ infinityString st

split :: String->Char->[String]
split [] ch = []
split st ch = start : split ending ch
    where (start, e) = break (==ch) st
          ending = drop 1 e

parseCSV t = mails
    where lines = split t '\n'
          tabbed = map (`split` '\t') lines
          col = map (!!3) tabbed
          filtered1 = map (filter ( /='\"')) col
          filtered2 = filter (elem '@') filtered1
          mails = filtered2

main = do
        text <- readFile "data.csv"
        mapM_ putStrLn (parseCSV text)