Republic of Turkey ID number validity checker

idValidate.hs

import Data.List (partition)
import Control.Arrow ((***))

idValidate n = (length ds == 11) && check1 && check2
  where ds = map (\x -> read [x] :: Int) (show n)
        (o, e) = map snd *** map snd $ partition (\(x,_)->odd x) $ zip [1..9] ds
        check1 = ds !! 9 == (sum o * 7 - sum e) `mod` 10
        check2 = ds !! 10 == sum (init ds) `mod` 10