Here is another one liner I am stuck at(Find permuation of string), here is my one line code :

permute myStr = foldr(\x acc -> (zipWith (\x1 y1 -> x1 ++ [x] ++ y1) (inits acc) (tails acc))) [] myStr

and here is 5 line error ;-(

    Occurs check: cannot construct the infinite type: a = [a]
      Expected type: [a]
      Inferred type: [[a]]
    In the expression:
        (zipWith (\ x1 y1 -> x1 ++ x ++ y1) (inits acc) (tails acc))
    In the first argument of `foldr', namely
        `(\ x acc
              -> (zipWith (\ x1 y1 -> x1 ++ x ++ y1) (inits acc) (tails acc)))'

Will really appreciate your help in moving ahead

Regards
Kaushal