generic-random: Generic random generators

[ generics, library, mit, testing ] [ Propose Tags ]

Please see the README below.

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Dependencies ad, base (==4.8.*), containers, hashable, hmatrix, ieee754, MonadRandom, mtl, QuickCheck, transformers, unordered-containers, vector [details]
License MIT
Author Li-yao Xia
Revised Revision 2 made by lyxia at Wed Jun 22 15:29:11 UTC 2016
Category Generics, Testing
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Source repo head: git clone
Uploaded by lyxia at Tue May 17 15:49:10 UTC 2016
Distributions LTSHaskell:, NixOS:, Stackage:, openSUSE:
Downloads 3007 total (41 in the last 30 days)
Rating 2.25 (votes: 2) [estimated by rule of succession]
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Readme for generic-random-

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Generic random generators

Define sized random generators for almost any type.

    {-# LANGUAGE DeriveDataTypeable #-}
    import Data.Data
    import Test.QuickCheck
    import Data.Random.Generics

    data Term = Lambda Int Term | App Term Term | Var Int
      deriving (Show, Data)

    instance Arbitrary Term where
      arbitrary = sized $ generatorPWith [positiveInts]

    positiveInts :: Alias Gen
    positiveInts =
      alias $ \() -> fmap getPositive arbitrary :: Gen Int

    main = sample (arbitrary :: Gen Term)
  • Objects of the same size (number of constructors) occur with the same probability (see Duchon et al., references below).
  • Implements rejection sampling and pointing.
  • Works with QuickCheck and MonadRandom.
  • Can be extended or modified with user defined generators.