Safe Haskell | Safe |
---|---|

Language | Haskell98 |

Some functions and generators suitable for writing QuickCheck properties.

- associative :: Eq a => (a -> a -> a) -> a -> a -> a -> Bool
- commutative :: Eq a => (a -> a -> a) -> a -> a -> Bool
- idempotent :: Eq a => (a -> a -> a) -> a -> Bool
- isZero :: Eq a => a -> (a -> a -> a) -> a -> Bool
- identity :: Eq a => a -> (a -> a -> a) -> a -> Bool
- leftDistributive :: Eq a => (a -> a -> a) -> (a -> a -> a) -> a -> a -> a -> Bool
- rightDistributive :: Eq a => (a -> a -> a) -> (a -> a -> a) -> a -> a -> a -> Bool
- distributive :: Eq a => (a -> a -> a) -> (a -> a -> a) -> a -> a -> a -> Bool
- natural :: Integral i => Gen i
- positive :: Integral i => Gen i
- maybeGen :: Gen a -> Gen (Maybe a)
- maybeCoGen :: (a -> Gen b -> Gen b) -> Maybe a -> Gen b -> Gen b
- listOfElements :: [a] -> Gen [a]
- elementsUnlessEmpty :: Arbitrary a => [a] -> Gen a
- two :: Gen a -> Gen (a, a)
- three :: Gen a -> Gen (a, a, a)
- runTests :: String -> [IO Bool] -> IO Bool

# Algebraic properties

associative :: Eq a => (a -> a -> a) -> a -> a -> a -> Bool Source #

Is the operator associative?

commutative :: Eq a => (a -> a -> a) -> a -> a -> Bool Source #

Is the operator commutative?

idempotent :: Eq a => (a -> a -> a) -> a -> Bool Source #

Is the operator idempotent?

leftDistributive :: Eq a => (a -> a -> a) -> (a -> a -> a) -> a -> a -> a -> Bool Source #

Does the first operator distribute (from the left) over the second one?

rightDistributive :: Eq a => (a -> a -> a) -> (a -> a -> a) -> a -> a -> a -> Bool Source #

Does the first operator distribute (from the right) over the second one?

distributive :: Eq a => (a -> a -> a) -> (a -> a -> a) -> a -> a -> a -> Bool Source #

Does the first operator distribute over the second one?

# Generators

maybeCoGen :: (a -> Gen b -> Gen b) -> Maybe a -> Gen b -> Gen b Source #

`Coarbitrary`

"generator" for `Maybe`

.

listOfElements :: [a] -> Gen [a] Source #

Generates a list of elements picked from a given list.

elementsUnlessEmpty :: Arbitrary a => [a] -> Gen a Source #

If the given list is non-empty, then an element from the list is generated, and otherwise an arbitrary element is generated.