So I have the code shuffle :: Int -> [a] -> [a] shuffle i [] = [] shuffle i cards = (cards!!i) : shuffle (fst pair) (delete (cards!!i) cards) where pair = randomR (0, 51) (mkStdGen 42) and it doesn't work, am I missing something? Cards.hs:39:51: Could not deduce (Eq a) from the context () arising from a use of `delete' at Cards.hs:39:51-73 Possible fix: add (Eq a) to the context of the type signature for `shuffle' In the second argument of `shuffle', namely `(delete (cards !! i) cards)' In the second argument of `(:)', namely `shuffle (fst pair) (delete (cards !! i) cards)' In the expression: (cards !! i) : shuffle (fst pair) (delete (cards !! i) cards) Failed, modules loaded: none.