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module RandomExample where
import System.Random
data Die = DieOne
| DieTwo
| DieThree
| DieFour
| DieFive
| DieSix
deriving (Eq, Show)
intToDie :: Int -> Die
intToDie n =
case n of
1 -> DieOne
2 -> DieTwo
3 -> DieThree
4 -> DieFour
5 -> DieFive
6 -> DieSix
-- Use 'error' __extermely_ sparingly
x -> error $ "intToDie got non 1-6 integer: " ++ show x
rollDieThreeTimes :: (Die, Die, Die)
rollDieThreeTimes = do
let s = mkStdGen 0
(d1, s1) = randomR (1, 6) s
(d2, s2) = randomR (1, 6) s1
(d3, _) = randomR (1, 6) s2
(intToDie d1, intToDie d2, intToDie d3)
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