I'm trying to do something I thought would be pretty simple, but it's giving me trouble. Given a list, say [1,2,3], I'd like to be able to generate an infinite list of random elements from that list, in this case maybe [1,2,1,3,2,1,3,2,3,1,2,...]. I'm using IO for random purely due to laziness (my own, not Haskell's). I was thinking the best way to do this might be to first write this function: randomElts :: [a] -> [IO a] randomElts [] = [] randomElts [x] = repeat (return x) randomElts xs = repeat r where bds = (1, length xs) xArr = listArray bds xs r = do i <- randomRIO bds return (xArr ! i) Then I should be able to do this in ghci:
sequence . take 5 $ randomElts [1,2,3] [*** Exception: stack overflow
Any idea what's going on? I thought laziness (Haskell's, not my own) would save me on this one. Thanks! Chad