random-source: Generic basis for random number generators

This is now deprecated and it is better to use the random package as the source of randomness.

Here's what you might have written before:

import qualified Data.Random as Random
import qualified Data.Random.Distribution.Bernoulli as Bernoulli

main :: IO ()
main = do
  x <- Random.sample $ Bernoulli.Bernoulli (0.5 :: Double) :: IO Double
  print x

And here's what you should write now (but there are many other options):

import qualified System.Random.Stateful as Random.Stateful
import qualified Data.Random as Random
import qualified Data.Random.Distribution.Bernoulli as Bernoulli
import qualified Control.Monad.Reader as Reader

main :: IO ()
main = do
  stdgen <- Random.Stateful.newIOGenM =<< Random.Stateful.newStdGen
  x <- Reader.runReaderT (Random.sample $ Bernoulli.Bernoulli (0.5 :: Double)) stdgen
        :: IO Double
  print x