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)