rando-0.0.0.2: src/System/Random/Pick.hs

module System.Random.Pick (
     pickOne
   , flipCoin
   ) where

import System.Random.TF.Init
import System.Random.TF.Instances

pickOne :: [x] -> IO x
pickOne l = do
   g <- newTFGen
   let (ix, _) = randomR (0, (length::[a]->Int) l - 1) g
   pure $ l !! ix

flipCoin :: IO Bool
flipCoin = pickOne [True, False]