On Fri, Apr 17, 2015 at 2:25 PM, Thomas Jakway <tjakway@nyu.edu> wrote:

genThree listMax = do --highest index in the list
        let listMin = 0 :: Int --lowest index in the list
        generatedMin <- state randomR (listMin, listMax)
        return generatedMin

What you're missing is a $:

The only chagne to our genThree functions is making it "state $" instead of "state".

#!/usr/bin/env runhaskell

import System.Random

import Control.Monad.State

genThree listMax = do --highest index in the list

let listMin = 0 :: Int --lowest index in the list

generatedMin <- state $ randomR (listMin, listMax)

return generatedMin

main = do

gen <- newStdGen

print $ evalState (genThree 10) gen