[Haskell-cafe] Occurs check error, help!

[boblettoj]

Yes sorry, that line should be indented, now it gives me a bigger error :(
What that line is trying to achieve is return a list where the first element
is the card at the given random number in the first list and the rest of the
list should be fed back in to shuffle along with a new random number.

shuffle :: Int -> [a] -> [a]
shuffle i [] = []
shuffle i cards = do
	gen <- mkStdGen
	return ([(cards!!i) : (shuffle (randomR (0, ((length cards)-2)) gen)
(delete (cards!!i) cards))])

I am now getting this error:

[1 of 1] Compiling Cards            ( cards.hs, interpreted )

cards.hs:32:1:
    Couldn't match expected type `[a]' against inferred type `Int -> b'
    In a stmt of a 'do' expression: gen <- mkStdGen
    In the expression:
        do { gen <- mkStdGen;
             return
               ([(cards !! i)
               : (shuffle
                    (randomR (0, ((length cards) - 2)) gen)
                    (delete (cards !! i) cards))]) }
    In the definition of `shuffle':
        shuffle i cards
                  = do { gen <- mkStdGen;
                         return
                           ([(cards !! i)
                           : (shuffle
                                (randomR (0, ((length cards) - 2)) gen)
                                (delete (cards !! i) cards))]) }

any ideas?


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