Data.Random.Source.StdGen
Description
This module provides functions useful for implementing new MonadRandom
and RandomSource instances for state-abstractions containing StdGen
values (the pure pseudorandom generator provided by the System.Random
module in the "random" package), as well as instances for some common
cases.
- getRandomPrimFromStdGenIO :: Prim a -> IO a
- getRandomPrimFromRandomGenRef :: (Monad m, ModifyRef sr m g, RandomGen g) => sr -> Prim a -> m a
- getRandomPrimFromRandomGenState :: (RandomGen g, MonadState g m) => Prim a -> m a
Documentation
getRandomPrimFromStdGenIO :: Prim a -> IO aSource
getRandomPrimFromRandomGenRef :: (Monad m, ModifyRef sr m g, RandomGen g) => sr -> Prim a -> m aSource
Given a mutable reference to a RandomGen generator, we can make a
RandomSource usable in any monad in which the reference can be modified.
getRandomPrimFromRandomGenState :: (RandomGen g, MonadState g m) => Prim a -> m aSource
Similarly, getRandomWordFromRandomGenState x can be used in any "state"
monad in the mtl sense whose state is a RandomGen generator.
Additionally, the standard mtl state monads have MonadRandom instances
which do precisely that, allowing an easy conversion of RVars and
other Distribution instances to "pure" random variables.