never executed always true always false

    1 reciprocal :: Int -> (String, Int)
    2 reciprocal n | n > 1 = ('0' : '.' : digits, recur)
    3              | otherwise = error
    4                   "attempting to compute reciprocal of number <= 1"
    5   where
    6   (digits, recur) = divide n 1 []
    7 divide :: Int -> Int -> [Int] -> (String, Int)
    8 divide n c cs | c `elem` cs = ([], position c cs)
    9               | r == 0      = (show q, 0)
   10               | r /= 0      = (show q ++ digits, recur)
   11   where
   12   (q, r) = (c*10) `quotRem` n
   13   (digits, recur) = divide n r (c:cs)
   14 
   15 position :: Int -> [Int] -> Int
   16 position n (x:xs) | n==x      = 1
   17                   | otherwise = 1 + position n xs
   18 
   19 showRecip :: Int -> String
   20 showRecip n =
   21   "1/" ++ show n ++ " = " ++
   22   if r==0 then d else take p d ++ "(" ++ drop p d ++ ")"
   23   where
   24   p = length d - r
   25   (d, r) = reciprocal n
   26 
   27 main = mainn 4
   28 mainn 0 = return ()
   29 mainn n = do
   30   number <- readLn
   31   putStrLn (showRecip number)
   32   mainn (pred n)