Test.QuickCheck.Arbitrary

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 Int8

Arbitrary Int16

Arbitrary Int32

Arbitrary Int64

Arbitrary Integer

Arbitrary Ordering

Arbitrary Word

Arbitrary Word8

Arbitrary Word16

Arbitrary Word32

Arbitrary Word64

Arbitrary ()

Arbitrary OrdC

Arbitrary OrdB

Arbitrary OrdA

Arbitrary C

Arbitrary B

Arbitrary A

Arbitrary a => Arbitrary [a]

(Integral a, Arbitrary a) => Arbitrary (Ratio a)

HasResolution a => Arbitrary (Fixed a)

(RealFloat a, Arbitrary a) => Arbitrary (Complex 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)

(Function a, CoArbitrary a, Arbitrary b) => Arbitrary (Fun a b)

(Function a, CoArbitrary a, Arbitrary b) => Arbitrary (:-> a b)

(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 Int8

CoArbitrary Int16

CoArbitrary Int32

CoArbitrary Int64

CoArbitrary Integer

CoArbitrary Ordering

CoArbitrary Word

CoArbitrary Word8

CoArbitrary Word16

CoArbitrary Word32

CoArbitrary Word64

CoArbitrary ()

CoArbitrary OrdC

CoArbitrary OrdB

CoArbitrary OrdA

CoArbitrary C

CoArbitrary B

CoArbitrary A

CoArbitrary a => CoArbitrary [a]

(Integral a, CoArbitrary a) => CoArbitrary (Ratio a)

HasResolution a => CoArbitrary (Fixed a)

(RealFloat a, CoArbitrary a) => CoArbitrary (Complex 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.

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

Generates an integral number. The number is chosen uniformly from the entire range of the type. You may want to use arbitrarySizedBoundedIntegral instead.

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

Generates an integral number from a bounded domain. The number is chosen from the entire range of the type, but small numbers are generated more often than big numbers. Inspired by demands from Phil Wadler.

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.

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.

arbitraryBoundedEnum :: (Bounded a, Enum a) => Gen a

Generates an element of a bounded enumeration.

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 :-).

coarbitraryEnum :: Enum a => a -> Gen b -> Gen b

A coarbitrary implementation for enums.

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.