Test.QuickCheck.DynamicLogic.Quantify

This module defines Quantifications, which are used together with forAllQ in DynamicLogic. A `Quantification t` can be used to generate a t, shrink a t, and recognise a generated t.

Documentation

data Quantification a

A Quantification over a type a is a generator that can be used with forAllQ to generate random values in DL scenarios. In addition to a QuickCheck generator a Quantification contains a shrinking strategy that ensures that shrunk values stay in the range of the generator.

Instances

(Eq a, Show a, Typeable a) => Quantifiable (Quantification a)

Defined in Test.QuickCheck.DynamicLogic.Quantify

Associated Types

type Quantifies (Quantification a)

Methods

quantify :: Quantification a -> Quantification (Quantifies (Quantification a))

type Quantifies (Quantification a)

Defined in Test.QuickCheck.DynamicLogic.Quantify

type Quantifies (Quantification a) = a

isEmptyQ :: Quantification a -> Bool

generateQ :: Quantification a -> Gen a

shrinkQ :: Quantification a -> a -> [a]

arbitraryQ :: Arbitrary a => Quantification a

Pack up an Arbitrary instance as a Quantification. Treats all values as being in range.

exactlyQ :: Eq a => a -> Quantification a

Generates exactly the given value. Does not shrink.

elementsQ :: Eq a => [a] -> Quantification a

Pick a random value from a list. Treated as an empty choice if the list is empty:

forAllQ (elementsQ []) == empty

oneofQ :: [Quantification a] -> Quantification a

Choose from a list of quantifications. Same as frequencyQ with all weights the same (and > 0).

frequencyQ :: [(Int, Quantification a)] -> Quantification a

Choose from a weighted list of quantifications. Treated as an empty choice if no quantification has weight > 0.

mapQ :: (a -> b, b -> a) -> Quantification a -> Quantification b

Quantification is not a Functor, since it also keeps track of the range of the generators. However, if you have two functions to :: a -> b from :: b -> a satisfying from . to = id you can go from a quantification over a to one over b. Note that the from function need only be defined on the image of to.

whereQ :: Quantification a -> (a -> Bool) -> Quantification a

Restrict the range of a quantification.

chooseQ :: (Arbitrary a, Random a, Ord a) => (a, a) -> Quantification a

Generate a random value in a given range (inclusive).

withGenQ :: Gen a -> (a -> [a]) -> Quantification a

Wrap a `Gen a` generator in a `Quantification a`. Uses given shrinker.

validQuantification :: Show a => Quantification a -> Property

class (Eq (Quantifies q), Show (Quantifies q), Typeable (Quantifies q)) => Quantifiable q where

Generalization of Quantifications, which lets you treat lists and tuples of quantifications as quantifications. For instance,

  ...
  (die1, die2) <- forAllQ (chooseQ (1, 6), chooseQ (1, 6))
  ...

Associated Types

type Quantifies q

The type of values quantified over.

Quantifies (Quantification a) = a

Methods

quantify :: q -> Quantification (Quantifies q)

Computing the actual Quantification.

Instances

Quantifiable a => Quantifiable [a]

Defined in Test.QuickCheck.DynamicLogic.Quantify

Associated Types

type Quantifies [a]

Methods

quantify :: [a] -> Quantification (Quantifies [a])

(Eq a, Show a, Typeable a) => Quantifiable (Quantification a)

Defined in Test.QuickCheck.DynamicLogic.Quantify

Associated Types

type Quantifies (Quantification a)

Methods

quantify :: Quantification a -> Quantification (Quantifies (Quantification a))

(Quantifiable a, Quantifiable b) => Quantifiable (a, b)

Defined in Test.QuickCheck.DynamicLogic.Quantify

Associated Types

type Quantifies (a, b)

Methods

quantify :: (a, b) -> Quantification (Quantifies (a, b))

(Quantifiable a, Quantifiable b, Quantifiable c) => Quantifiable (a, b, c)

Defined in Test.QuickCheck.DynamicLogic.Quantify

Associated Types

type Quantifies (a, b, c)

Methods

quantify :: (a, b, c) -> Quantification (Quantifies (a, b, c))

(Quantifiable a, Quantifiable b, Quantifiable c, Quantifiable d) => Quantifiable (a, b, c, d)

Defined in Test.QuickCheck.DynamicLogic.Quantify

Associated Types

type Quantifies (a, b, c, d)

Methods

quantify :: (a, b, c, d) -> Quantification (Quantifies (a, b, c, d))

(Quantifiable a, Quantifiable b, Quantifiable c, Quantifiable d, Quantifiable e) => Quantifiable (a, b, c, d, e)

Defined in Test.QuickCheck.DynamicLogic.Quantify

Associated Types

type Quantifies (a, b, c, d, e)

Methods

quantify :: (a, b, c, d, e) -> Quantification (Quantifies (a, b, c, d, e))