QuickCheck-2.1.0.3: Automatic testing of Haskell programs Contents Index

Test.QuickCheck.Arbitrary

Contents Arbitrary and CoArbitrary classes. Helper functions for implementing arbitrary Helper functions for implementing shrink Helper functions for implementing coarbitrary Generators which use arbitrary

Synopsis

class Arbitrary a where arbitrary :: Gen a shrink :: a -> [a] class CoArbitrary a where coarbitrary :: a -> Gen c -> Gen c arbitrarySizedIntegral :: Num a => Gen a arbitrarySizedFractional :: Fractional a => Gen a arbitraryBoundedIntegral :: (Bounded a, Integral a) => Gen a arbitraryBoundedRandom :: (Bounded a, Random a) => Gen a shrinkNothing :: a -> [a] shrinkList :: (a -> [a]) -> [a] -> [[a]] shrinkIntegral :: Integral a => a -> [a] shrinkRealFrac :: RealFrac a => a -> [a] (><) :: (Gen a -> Gen a) -> (Gen a -> Gen a) -> Gen a -> Gen a coarbitraryIntegral :: Integral a => a -> Gen b -> Gen b coarbitraryReal :: Real a => a -> Gen b -> Gen b coarbitraryShow :: Show a => a -> Gen b -> Gen b vector :: Arbitrary a => Int -> Gen [a] orderedList :: (Ord a, Arbitrary a) => Gen [a]

Arbitrary and CoArbitrary classes.

class Arbitrary a where

Random generation and shrinking of values. Methods arbitrary :: Gen a A generator for values of the given type. shrink :: a -> [a] Produces a (possibly) empty list of all the possible immediate shrinks of the given value. Instances Arbitrary Bool Arbitrary Char Arbitrary Double Arbitrary Float Arbitrary Int Arbitrary Integer Arbitrary () Arbitrary OrdC Arbitrary OrdB Arbitrary OrdA Arbitrary C Arbitrary B Arbitrary A Arbitrary a => Arbitrary [a] (Integral a, Arbitrary a) => Arbitrary (Ratio a) Arbitrary a => Arbitrary (Maybe a) Arbitrary a => Arbitrary (Smart a) Arbitrary a => Arbitrary (Shrink2 a) (Num a, Ord a, Arbitrary a) => Arbitrary (NonNegative a) (Num a, Ord a, Arbitrary a) => Arbitrary (NonZero a) (Num a, Ord a, Arbitrary a) => Arbitrary (Positive a) Arbitrary a => Arbitrary (NonEmptyList a) (Ord a, Arbitrary a) => Arbitrary (OrderedList a) Arbitrary a => Arbitrary (Fixed a) Arbitrary a => Arbitrary (Blind a) (CoArbitrary a, Arbitrary b) => Arbitrary (a -> b) (Arbitrary a, Arbitrary b) => Arbitrary (Either a b) (Arbitrary a, Arbitrary b) => Arbitrary (a, b) (Arbitrary a, ShrinkState s a) => Arbitrary (Shrinking s a) (FunArbitrary a, Arbitrary b) => Arbitrary (Fun a b) (FunArbitrary a, Arbitrary c) => Arbitrary (:-> a c) (Arbitrary a, Arbitrary b, Arbitrary c) => Arbitrary (a, b, c) (Arbitrary a, Arbitrary b, Arbitrary c, Arbitrary d) => Arbitrary (a, b, c, d) (Arbitrary a, Arbitrary b, Arbitrary c, Arbitrary d, Arbitrary e) => Arbitrary (a, b, c, d, e)

class CoArbitrary a where

Used for random generation of functions. Methods coarbitrary :: a -> Gen c -> Gen c Used to generate a function of type a -> c. The implementation should use the first argument to perturb the random generator given as the second argument. the returned generator is then used to generate the function result. You can often use variant and >< to implement coarbitrary. Instances CoArbitrary Bool CoArbitrary Char CoArbitrary Double CoArbitrary Float CoArbitrary Int CoArbitrary Integer CoArbitrary () CoArbitrary OrdC CoArbitrary OrdB CoArbitrary OrdA CoArbitrary C CoArbitrary B CoArbitrary A CoArbitrary a => CoArbitrary [a] (Integral a, CoArbitrary a) => CoArbitrary (Ratio a) CoArbitrary a => CoArbitrary (Maybe a) (Arbitrary a, CoArbitrary b) => CoArbitrary (a -> b) (CoArbitrary a, CoArbitrary b) => CoArbitrary (Either a b) (CoArbitrary a, CoArbitrary b) => CoArbitrary (a, b) (CoArbitrary a, CoArbitrary b, CoArbitrary c) => CoArbitrary (a, b, c) (CoArbitrary a, CoArbitrary b, CoArbitrary c, CoArbitrary d) => CoArbitrary (a, b, c, d) (CoArbitrary a, CoArbitrary b, CoArbitrary c, CoArbitrary d, CoArbitrary e) => CoArbitrary (a, b, c, d, e)

Helper functions for implementing arbitrary

arbitrarySizedIntegral :: Num a => Gen a

Generates an integral number. The number can be positive or negative and its maximum absolute value depends on the size parameter.

arbitrarySizedFractional :: Fractional a => Gen a

Generates a fractional number. The number can be positive or negative and its maximum absolute value depends on the size parameter.

arbitraryBoundedIntegral :: (Bounded a, Integral a) => Gen a

Generates an integral number. The number is chosen from the entire range of the type.

arbitraryBoundedRandom :: (Bounded a, Random a) => Gen a

Generates an element of a bounded type. The element is chosen from the entire range of the type.

Helper functions for implementing shrink

shrinkNothing :: a -> [a]

Returns no shrinking alternatives.

shrinkList :: (a -> [a]) -> [a] -> [[a]]

shrinkIntegral :: Integral a => a -> [a]

Shrink an integral number.

shrinkRealFrac :: RealFrac a => a -> [a]

Shrink a fraction.

Helper functions for implementing coarbitrary

(><) :: (Gen a -> Gen a) -> (Gen a -> Gen a) -> Gen a -> Gen a

Combine two generator perturbing functions, for example the results of calls to variant or coarbitrary.

coarbitraryIntegral :: Integral a => a -> Gen b -> Gen b

A coarbitrary implementation for integral numbers.

coarbitraryReal :: Real a => a -> Gen b -> Gen b

A coarbitrary implementation for real numbers.

coarbitraryShow :: Show a => a -> Gen b -> Gen b

coarbitrary helper for lazy people :-).

Generators which use arbitrary

vector :: Arbitrary a => Int -> Gen [a]

Generates a list of a given length.

orderedList :: (Ord a, Arbitrary a) => Gen [a]

Generates an ordered list of a given length.

Produced by Haddock version 2.6.0