foundation-0.0.15: Alternative prelude with batteries and no dependencies

LicenseBSD-style
Stabilityexperimental
PortabilityGood
Safe HaskellNone
LanguageHaskell2010

Foundation.Random

Description

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.

Synopsis

Documentation

class 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) #

newtype MonadRandomState gen a #

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

Constructors

MonadRandomState 

Fields

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

Run a pure computation with a Random Generator in the MonadRandomState

type 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.

type RNGv1 = State #