Modulefoundation-0.0.30Haskell2010

Foundation.Random

This module deals with the random subsystem abstractions.

It provide 2 different set of abstractions:

The first abstraction that allow a monad to generate random through the MonadRandom class.
The second abstraction to make generic random generator RandomGen and a small State monad like wrapper MonadRandomState to abstract a generator.

3 types
2 classes
1 value

Packagefoundation-0.0.30
Exports6
LanguageHaskell2010
LicenceBSD-3-Clause
SourceRandom.hs

classclass (Functor m, Applicative m, Monad m) => MonadRandom (m :: Type -> Type) where

A monad constraint that allows to generate random bytes

Methods

getRandomBytes :: CountOf Word8 -> m (UArray Word8)
getRandomWord64 :: m Word64
getRandomF32 :: m Float
getRandomF64 :: m Double

Instances2MonadRandom

MonadRandom IODefined in foundation-0.0.30 · Foundation.Random.Class
RandomGen gen => MonadRandom (MonadRandomState gen)Defined in foundation-0.0.30 · Foundation.Random.DRG

classclass RandomGen gen where

A Deterministic Random Generator (DRG) class

Methods

randomNew :: MonadRandom m => m gen
Initialize a new random generator
randomNewFrom :: UArray Word8 -> Maybe gen
Initialize a new random generator from a binary seed.
If Nothing is returned, then the data is not acceptable for creating a new random generator.
randomGenerate :: CountOf Word8 -> gen -> (UArray Word8, gen)
Generate N bytes of randomness from a DRG
randomGenerateWord64 :: gen -> (Word64, gen)
Generate a Word64 from a DRG
randomGenerateF32 :: gen -> (Float, gen)
randomGenerateF64 :: gen -> (Double, gen)

Instances2RandomGen

RandomGen StateDefined in foundation-0.0.30 · Foundation.Random.ChaChaDRG
RandomGen StateDefined in foundation-0.0.30 · Foundation.Random.XorShift

newtypenewtype MonadRandomState gen a

A simple Monad class very similar to a State Monad with the state being a RandomGenerator.

Constructors

MonadRandomState
- runRandomState :: gen -> (a, gen)

Instances4Monad, Functor, Applicative, MonadRandom

Monad (MonadRandomState gen)Defined in foundation-0.0.30 · Foundation.Random.DRG
Functor (MonadRandomState gen)Defined in foundation-0.0.30 · Foundation.Random.DRG
Applicative (MonadRandomState gen)Defined in foundation-0.0.30 · Foundation.Random.DRG
RandomGen gen => MonadRandom (MonadRandomState gen)Defined in foundation-0.0.30 · Foundation.Random.DRG

valuewithRandomGenerator

:: RandomGen gen
=> gen
-> MonadRandomState gen a
-> (a, gen)

Run a pure computation with a Random Generator in the MonadRandomState

typetype RNG = RNGv1

An alias to the default choice of deterministic random number generator

Unless, you want to have the stability of a specific random number generator, e.g. for tests purpose, it's recommended to use this alias so that you would keep up to date with possible bugfixes, or change of algorithms.

typetype RNGv1 = State