Safe Haskell	Safe
Language	Haskell2010

Test.QuickCheck.GenT

Contents

Common generator combinators
Partial functions
Non-partial functions resulting in Maybe

Description

Most of the code is borrowed from a mailing list discussion. Therefor, credits go to Paul Johnson and Felix Martini.

Synopsis

newtype GenT m a = GenT {
- unGenT :: QCGen -> Int -> m a
}
runGenT :: GenT m a -> Gen (m a)
class (Applicative g, Monad g) => MonadGen g where
- liftGen :: Gen a -> g a
- variant :: Integral n => n -> g a -> g a
- sized :: (Int -> g a) -> g a
- resize :: Int -> g a -> g a
- choose :: Random a => (a, a) -> g a
var :: Integral n => n -> QCGen -> QCGen
suchThat :: MonadGen m => m a -> (a -> Bool) -> m a
suchThatMaybe :: MonadGen m => m a -> (a -> Bool) -> m (Maybe a)
listOf :: MonadGen m => m a -> m [a]
listOf1 :: MonadGen m => m a -> m [a]
vectorOf :: MonadGen m => Int -> m a -> m [a]
oneof :: MonadGen m => [m a] -> m a
frequency :: MonadGen m => [(Int, m a)] -> m a
elements :: MonadGen m => [a] -> m a
growingElements :: MonadGen m => [a] -> m a
oneofMay :: MonadGen m => [m a] -> m (Maybe a)
elementsMay :: MonadGen m => [a] -> m (Maybe a)
growingElementsMay :: MonadGen m => [a] -> m (Maybe a)

Documentation

newtype GenT m a Source #

Constructors

GenT
Fields unGenT :: QCGen -> Int -> m a

Instances

MonadTrans GenT Source #
Instance details Defined in Test.QuickCheck.GenT Methods lift :: Monad m => m a -> GenT m a #
Monad m => Monad (GenT m) Source #
Instance details Defined in Test.QuickCheck.GenT Methods (>>=) :: GenT m a -> (a -> GenT m b) -> GenT m b # (>>) :: GenT m a -> GenT m b -> GenT m b # return :: a -> GenT m a # fail :: String -> GenT m a #
Functor m => Functor (GenT m) Source #
Instance details Defined in Test.QuickCheck.GenT Methods fmap :: (a -> b) -> GenT m a -> GenT m b # (<$) :: a -> GenT m b -> GenT m a #
(Functor m, Monad m) => Applicative (GenT m) Source #
Instance details Defined in Test.QuickCheck.GenT Methods pure :: a -> GenT m a # (<>) :: GenT m (a -> b) -> GenT m a -> GenT m b # liftA2 :: (a -> b -> c) -> GenT m a -> GenT m b -> GenT m c # (>) :: GenT m a -> GenT m b -> GenT m b # (<*) :: GenT m a -> GenT m b -> GenT m a #
MonadIO m => MonadIO (GenT m) Source #
Instance details Defined in Test.QuickCheck.GenT Methods liftIO :: IO a -> GenT m a #
(Applicative m, Monad m) => MonadGen (GenT m) Source #
Instance details Defined in Test.QuickCheck.GenT Methods liftGen :: Gen a -> GenT m a Source # variant :: Integral n => n -> GenT m a -> GenT m a Source # sized :: (Int -> GenT m a) -> GenT m a Source # resize :: Int -> GenT m a -> GenT m a Source # choose :: Random a => (a, a) -> GenT m a Source #

runGenT :: GenT m a -> Gen (m a) Source #

class (Applicative g, Monad g) => MonadGen g where Source #

Methods

liftGen :: Gen a -> g a Source #

variant :: Integral n => n -> g a -> g a Source #

sized :: (Int -> g a) -> g a Source #

resize :: Int -> g a -> g a Source #

choose :: Random a => (a, a) -> g a Source #

Instances

MonadGen Gen Source #
Instance details Defined in Test.QuickCheck.GenT Methods liftGen :: Gen a -> Gen a Source # variant :: Integral n => n -> Gen a -> Gen a Source # sized :: (Int -> Gen a) -> Gen a Source # resize :: Int -> Gen a -> Gen a Source # choose :: Random a => (a, a) -> Gen a Source #
(Applicative m, Monad m) => MonadGen (GenT m) Source #
Instance details Defined in Test.QuickCheck.GenT Methods liftGen :: Gen a -> GenT m a Source # variant :: Integral n => n -> GenT m a -> GenT m a Source # sized :: (Int -> GenT m a) -> GenT m a Source # resize :: Int -> GenT m a -> GenT m a Source # choose :: Random a => (a, a) -> GenT m a Source #

var :: Integral n => n -> QCGen -> QCGen Source #

Private variant-generating function. Converts an integer into a chain of (fst . split) and (snd . split) applications. Every integer (including negative ones) will give rise to a different random number generator in log2 n steps.

Common generator combinators

suchThat :: MonadGen m => m a -> (a -> Bool) -> m a Source #

Generates a value that satisfies a predicate.

suchThatMaybe :: MonadGen m => m a -> (a -> Bool) -> m (Maybe a) Source #

Tries to generate a value that satisfies a predicate.

listOf :: MonadGen m => m a -> m [a] Source #

Generates a list of random length. The maximum length depends on the size parameter.

listOf1 :: MonadGen m => m a -> m [a] Source #

Generates a non-empty list of random length. The maximum length depends on the size parameter.

vectorOf :: MonadGen m => Int -> m a -> m [a] Source #

Generates a list of the given length.

Partial functions

oneof :: MonadGen m => [m a] -> m a Source #

Randomly uses one of the given generators. The input list must be non-empty.

frequency :: MonadGen m => [(Int, m a)] -> m a Source #

Chooses one of the given generators, with a weighted random distribution. The input list must be non-empty.

elements :: MonadGen m => [a] -> m a Source #

Generates one of the given values. The input list must be non-empty.

growingElements :: MonadGen m => [a] -> m a Source #

Takes a list of elements of increasing size, and chooses among an initial segment of the list. The size of this initial segment increases with the size parameter. The input list must be non-empty.

Non-partial functions resulting in Maybe

oneofMay :: MonadGen m => [m a] -> m (Maybe a) Source #

Randomly uses one of the given generators.

elementsMay :: MonadGen m => [a] -> m (Maybe a) Source #

Generates one of the given values.

growingElementsMay :: MonadGen m => [a] -> m (Maybe a) Source #

Takes a list of elements of increasing size, and chooses among an initial segment of the list. The size of this initial segment increases with the size parameter.