a package:QuickCheck

Modifies a property so that it will be tested repeatedly. Opposite of once.

List all properties in the current module. $allProperties has type [(String, Property)]. allProperties has the same issue with scoping as quickCheckAll: see the note there about return [].

Apply a binary function to random arguments.

Apply a ternary function to random arguments.

Apply a function of arity 4 to random arguments.

Extracts the value of a function. Fn is the pattern equivalent of this function.

prop :: Fun String Integer -> Bool
prop f = applyFun f "banana" == applyFun f "monkey"
|| applyFun f "banana" == applyFun f "elephant"

Extracts the value of a binary function. Fn2 is the pattern equivalent of this function.

prop_zipWith :: Fun (Int, Bool) Char -> [Int] -> [Bool] -> Bool
prop_zipWith f xs ys = zipWith (applyFun2 f) xs ys == [ applyFun2 f x y | (x, y) <- zip xs ys]

Extracts the value of a ternary function. Fn3 is the pattern equivalent of this function.

A generator for values of the given type. It is worth spending time thinking about what sort of test data you want - good generators are often the difference between finding bugs and not finding them. You can use sample, label and classify to check the quality of your test data. There is no generic arbitrary implementation included because we don't know how to make a high-quality one. If you want one, consider using the testing-feat or generic-random packages. The QuickCheck manual goes into detail on how to write good generators. Make sure to look at it, especially if your type is recursive!

Generates a random ASCII character (0-127).

Generates an element of a bounded enumeration.

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

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

Generates a printable Unicode character.

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.

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

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

Generates a natural number. The number's maximum value depends on the size parameter.

Generates any Unicode character (but not a surrogate)

Alias to applyFun.

Allows embedding non-monadic properties into monadic ones.