Gen
Namespace: FsCheck
Combinators to build custom random generators for any type.
Table of contents
Create generators from generators
Functions and values
| Function or value | Description |
collect f l
Signature: f:('a -> Gen<'b>) -> l:seq<'a> -> Gen<'b list>
Type parameters: 'a, 'b Attributes: [<CompiledName("CollectToList")>] |
Traverse the given enumerable into a generator of a list using the specified binder function to create generators. CompiledName: |
collectToSeq f l
Signature: f:('?9890 -> Gen<'?9891>) -> l:seq<'?9890> -> Gen<seq<'?9891>>
Type parameters: '?9890, '?9891 Attributes: [<CompiledName("Collect")>] |
Traverse the given enumerable into a generator of an enumerable using the specified binder function to create generators. CompiledName: |
Creating generators from generators
Functions and values
| Function or value | Description |
collectToArr f xs
Signature: f:('?9895 -> Gen<'?9896>) -> xs:'?9895 array -> Gen<'?9896 []>
Type parameters: '?9895, '?9896 Attributes: [<CompiledName("CollectToArray")>] |
Traverse the given array into a generator of an array using the specified binder function to create generators. CompiledName: |
Other module members
Functions and values
| Function or value | Description |
apply f gn
Signature: f:Gen<('a -> 'b)> -> gn:Gen<'a> -> Gen<'b>
Type parameters: 'a, 'b Attributes: [<CompiledName("Apply")>] |
Apply the given Gen function to the given generator, aka the applicative <*> operator. CompiledName: |
array2DOf(g)
Signature: g:Gen<'a> -> Gen<'a [,]>
Type parameters: 'a Attributes: [<CompiledName("Array2DOf")>] |
Generates a 2D array. The square root of the size is the maximum number of rows and columns. CompiledName: |
array2DOfDim(rows, cols) g
Signature: (rows:int * cols:int) -> g:Gen<'a> -> Gen<'a [,]>
Type parameters: 'a Attributes: [<CompiledName("Array2DOf")>] |
Generates a 2D array of the given dimensions. CompiledName: |
arrayOf(g)
Signature: g:Gen<'a> -> Gen<'a []>
Type parameters: 'a Attributes: [<CompiledName("ArrayOf")>] |
Generates an array using the specified generator. The maximum length is the size+1. CompiledName: |
arrayOfLength n g
Signature: n:int -> g:Gen<'a> -> Gen<'a []>
Type parameters: 'a Attributes: [<CompiledName("ArrayOf")>] |
Generates an array of a specified length. CompiledName: |
choose(l, h)
Signature: (l:int * h:int) -> Gen<int>
Attributes: [<CompiledName("Choose")>] |
Generates an integer between l and h, inclusive. CompiledName: |
constant(v)
Signature: v:'b -> Gen<'b>
Type parameters: 'b Attributes: [<CompiledName("Constant")>] |
Always generate the same instance v. See also fresh. CompiledName: |
elements(xs)
Signature: xs:seq<'a> -> Gen<'a>
Type parameters: 'a Attributes: [<CompiledName("Elements")>] |
Build a generator that randomly generates one of the values in the given non-empty seq. CompiledName: |
elementsArr(values)
Signature: values:'?9815 array -> Gen<'?9815>
Type parameters: '?9815 Attributes: [<CompiledName("Elements")>] [<CompilerMessage("This method is not intended for use from F#.", 10001, IsHidden = true, IsError = false)>] |
Build a generator that randomly generates one of the values in the given non-empty seq. CompiledName: |
eval size seed arg3
Signature: size:int -> seed:StdGen -> Gen<'b> -> 'b
Type parameters: 'b Attributes: [<CompiledName("Eval")>] |
Generates a value of the give size with the given seed. CompiledName: |
filter predicate generator
Signature: predicate:('a18 -> bool) -> generator:Gen<'a18> -> Gen<'a18>
Type parameters: 'a18 Attributes: [<CompiledName("Filter")>] |
Generates a value that satisfies a predicate. Contrary to tryFilter, this function keeps re-trying by increasing the size of the original generator ad infinitum. Make sure there is a high probability that the predicate is satisfied. The CompiledName: |
four(g)
Signature: g:Gen<'b> -> Gen<'b * 'b * 'b * 'b>
Type parameters: 'b Attributes: [<CompiledName("Four")>] |
Build a generator that generates a 4-tuple of the values generated by the given generator. CompiledName: |
frequency(xs)
Signature: xs:seq<int * Gen<'a18>> -> Gen<'a18>
Type parameters: 'a18 Attributes: [<CompiledName("Frequency")>] |
Build a generator that generates a value from one of the generators in the given non-empty seq, with given probabilities. The sum of the probabilities must be larger than zero. CompiledName: |
frequencySeqWeightAndValue(...)
Signature: weightedValues:seq<WeightAndValue<Gen<'a>>> -> Gen<'a>
Type parameters: 'a Attributes: [<CompiledName("Frequency")>] [<CompilerMessage("This method is not intended for use from F#.", 10001, IsHidden = true, IsError = false)>] |
Build a generator that generates a value from one of the generators in the given non-empty seq, with given probabilities. The sum of the probabilities must be larger than zero. CompiledName: |
frequencyTupleArr(weightedValues)
Signature: weightedValues:(int * Gen<'a>) [] -> Gen<'a>
Type parameters: 'a Attributes: [<CompiledName("Frequency")>] [<CompilerMessage("This method is not intended for use from F#.", 10001, IsHidden = true, IsError = false)>] |
Build a generator that generates a value from one of the generators in the given non-empty seq, with given probabilities. The sum of the probabilities must be larger than zero. CompiledName: |
frequencyWeightAndValueArr(...)
Signature: weightedValues:WeightAndValue<Gen<'a>> [] -> Gen<'a>
Type parameters: 'a Attributes: [<CompiledName("Frequency")>] [<CompilerMessage("This method is not intended for use from F#.", 10001, IsHidden = true, IsError = false)>] |
Build a generator that generates a value from one of the generators in the given non-empty seq, with given probabilities. The sum of the probabilities must be larger than zero. CompiledName: |
fresh(fv)
Signature: fv:(unit -> '?9797) -> Gen<'?9797>
Type parameters: '?9797 Attributes: [<CompiledName("Fresh")>] |
Generate a fresh instance every time the generator is called. Useful for mutable objects. See also constant. CompiledName: |
freshFunc(fv)
Signature: fv:Func<'?9799> -> Gen<'?9799>
Type parameters: '?9799 Attributes: [<CompiledName("Fresh")>] [<CompilerMessage("This method is not intended for use from F#.", 10001, IsHidden = true, IsError = false)>] |
Generate a fresh instance every time the generatoris called. Useful for mutable objects. See also constant. CompiledName: |
growingElements(xs)
Signature: xs:seq<'?9819> -> Gen<'?9819>
Type parameters: '?9819 Attributes: [<CompiledName("GrowingElements")>] |
Build a generator that takes a non-empty sequence and randomly generates one of the values among an initial segment of that sequence. The size of this initial segment increases with the size parameter. Essentially this generator is Gen.elements but taking also the runtime size into account. CompiledName: |
listOf(gn)
Signature: gn:Gen<'a> -> Gen<'a list>
Type parameters: 'a Attributes: [<CompiledName("ListOf")>] |
Generates a list of random length. The maximum length depends on the size parameter. CompiledName: |
listOfLength n arb
Signature: n:int -> arb:Gen<'a18> -> Gen<'a18 list>
Type parameters: 'a18 Attributes: [<CompiledName("ListOf")>] |
Generates a list of given length, containing values generated by the given generator. CompiledName: |
map f gen
Signature: f:('a -> 'b) -> gen:Gen<'a> -> Gen<'b>
Type parameters: 'a, 'b Attributes: [<CompiledName("Map")>] |
Apply the function f to the value in the generator, yielding a new generator. CompiledName: |
map2 f a b
Signature: f:('c -> 'd -> 'e) -> a:Gen<'c> -> b:Gen<'d> -> Gen<'e>
Type parameters: 'c, 'd, 'e Attributes: [<CompiledName("Map2")>] |
Map the given function over values to a function over generators of those values. CompiledName: |
map3 f a b c
Signature: f:('a18 -> 'a19 -> 'a20 -> 'a21) -> a:Gen<'a18> -> b:Gen<'a19> -> c:Gen<'a20> -> Gen<'a21>
Type parameters: 'a18, 'a19, 'a20, 'a21 Attributes: [<CompiledName("Map3")>] |
Map the given function over values to a function over generators of those values. CompiledName: |
map4 f a b c d
Signature: f:('?9848 -> '?9849 -> '?9850 -> '?9851 -> '?9852) -> a:Gen<'?9848> -> b:Gen<'?9849> -> c:Gen<'?9850> -> d:Gen<'?9851> -> Gen<'?9852>
Type parameters: '?9848, '?9849, '?9850, '?9851, '?9852 Attributes: [<CompiledName("Map4")>] |
Map the given function over values to a function over generators of those values. CompiledName: |
map5 f a b c d e
Signature: f:('a18 -> 'a19 -> 'a20 -> 'a21 -> 'a22 -> 'a23) -> a:Gen<'a18> -> b:Gen<'a19> -> c:Gen<'a20> -> d:Gen<'a21> -> e:Gen<'a22> -> Gen<'a23>
Type parameters: 'a18, 'a19, 'a20, 'a21, 'a22, 'a23 Attributes: [<CompiledName("Map5")>] |
Map the given function over values to a function over generators of those values. CompiledName: |
map6 f a b c d e g
Signature: f:('?9863 -> '?9864 -> '?9865 -> '?9866 -> '?9867 -> '?9868 -> '?9869) -> a:Gen<'?9863> -> b:Gen<'?9864> -> c:Gen<'?9865> -> d:Gen<'?9866> -> e:Gen<'?9867> -> g:Gen<'?9868> -> Gen<'?9869>
Type parameters: '?9863, '?9864, '?9865, '?9866, '?9867, '?9868, '?9869 Attributes: [<CompiledName("Map6")>] |
Map the given function over values to a function over generators of those values. CompiledName: |
nonEmptyListOf(gn)
Signature: gn:Gen<'b> -> Gen<'b list>
Type parameters: 'b Attributes: [<CompiledName("NonEmptyListOf")>] |
Generates a non-empty list of random length. The maximum length depends on the size parameter. CompiledName: |
oneof(gens)
Signature: gens:seq<Gen<'a>> -> Gen<'a>
Type parameters: 'a Attributes: [<CompiledName("OneOf")>] |
Build a generator that generates a value from one of the generators in the given non-empty seq, with equal probability. CompiledName: |
oneOfArr(generators)
Signature: generators:Gen<'?9823> array -> Gen<'?9823>
Type parameters: '?9823 Attributes: [<CompiledName("OneOf")>] [<CompilerMessage("This method is not intended for use from F#.", 10001, IsHidden = true, IsError = false)>] |
Build a generator that generates a value from one of the given generators, with equal probability. CompiledName: |
optionOf(g)
Signature: g:Gen<'b> -> Gen<'b option>
Type parameters: 'b |
Generate an option value that is 'None' 1/8 of the time. |
piles k sum
Signature: k:int -> sum:int -> Gen<int []>
Attributes: [<CompiledName("Piles")>] |
Generates a random array of length k where the sum of all elements equals the given sum. CompiledName: |
resize newSize arg2
Signature: newSize:int -> Gen<'b> -> Gen<'b>
Type parameters: 'b Attributes: [<CompiledName("Resize")>] |
Override the current size of the test. resize n g invokes generator g with size parameter n. CompiledName: |
sample size n generator
Signature: size:int -> n:int -> generator:Gen<'b> -> 'b list
Type parameters: 'b Attributes: [<CompiledName("Sample")>] |
Generates n values of the given size. CompiledName: |
sequence(l)
Signature: l:seq<Gen<'?9888>> -> Gen<'?9888 list>
Type parameters: '?9888 Attributes: [<CompiledName("SequenceToList")>] |
Sequence the given enumerable of generators into a generator of a list. CompiledName: |
sequenceToArr(generators)
Signature: generators:Gen<'b> array -> Gen<'b []>
Type parameters: 'b Attributes: [<CompiledName("Sequence")>] |
Sequence the given array of generators into a generator of an array. CompiledName: |
sequenceToSeq(generators)
Signature: generators:seq<Gen<'?9893>> -> Gen<seq<'?9893>>
Type parameters: '?9893 Attributes: [<CompiledName("Sequence")>] |
Sequence the given enumerable of generators into a generator of an enumerable. CompiledName: |
shuffle(xs)
Signature: xs:seq<'?9904> -> Gen<'?9904 array>
Type parameters: '?9904 Attributes: [<CompiledName("Shuffle")>] |
Generates a random permutation of the given sequence. CompiledName: |
sized(fgen)
Signature: fgen:(int -> Gen<'b>) -> Gen<'b>
Type parameters: 'b Attributes: [<CompiledName("Sized")>] |
Obtain the current size. sized g calls g, passing it the current size as a parameter. CompiledName: |
sizedFunc(sizedGen)
Signature: sizedGen:Func<int,Gen<'?9806>> -> Gen<'?9806>
Type parameters: '?9806 Attributes: [<CompiledName("Sized")>] [<CompilerMessage("This method is not intended for use from F#.", 10001, IsHidden = true, IsError = false)>] |
Obtain the current size. sized g calls g, passing it the current size as a parameter. CompiledName: |
subListOf(l)
Signature: l:seq<'?9923> -> Gen<'?9923 list>
Type parameters: '?9923 Attributes: [<CompiledName("SubListOfToList")>] |
Generates sublists of the given sequence. CompiledName: |
subListOfArr(s)
Signature: s:'?9927 array -> Gen<IList<'?9927>>
Type parameters: '?9927 Attributes: [<CompiledName("SubListOf")>] [<CompilerMessage("This method is not intended for use from F#.", 10001, IsHidden = true, IsError = false)>] |
Generates sublists of the given arguments. CompiledName: |
subListOfToIList(s)
Signature: s:seq<'?9925> -> Gen<IList<'?9925>>
Type parameters: '?9925 Attributes: [<CompiledName("SubListOf")>] [<CompilerMessage("This method is not intended for use from F#.", 10001, IsHidden = true, IsError = false)>] |
Generates sublists of the given IEnumerable. CompiledName: |
suchThat
Signature: ('?9916 -> bool) -> Gen<'?9916> -> Gen<'?9916>
Type parameters: '?9916 Attributes: [<Obsolete("This function will be removed in a future version of FsCheck. Please use the synonyms where or filter instead.")>] [<CompiledName("SuchThat")>] |
WARNING: This API is obsolete
This function will be removed in a future version of FsCheck. Please use the synonyms where or filter instead.
Generates a value that satisfies a predicate. Contrary to suchThatOption, this function keeps re-trying by increasing the size of the original generator ad infinitum. Make sure there is a high probability that the predicate is satisfied. CompiledName: |
suchThatOption
Signature: ('?9910 -> bool) -> Gen<'?9910> -> Gen<'?9910 option>
Type parameters: '?9910 Attributes: [<Obsolete("This function will be removed in a future version of FsCheck. Please use the synonyms tryWhere or tryFilter instead.")>] [<CompiledName("SuchThatOption")>] [<EditorBrowsable(1)>] |
WARNING: This API is obsolete
This function will be removed in a future version of FsCheck. Please use the synonyms tryWhere or tryFilter instead.
Tries to generate a value that satisfies a predicate. This function 'gives up' by generating None if the given original generator did not generate any values that satisfied the predicate, after trying to get values by increasing its size. CompiledName: |
three(g)
Signature: g:Gen<'b> -> Gen<'b * 'b * 'b>
Type parameters: 'b Attributes: [<CompiledName("Three")>] |
Build a generator that generates a 3-tuple of the values generated by the given generator. CompiledName: |
tryFilter predicate generator
Signature: predicate:('?9908 -> bool) -> generator:Gen<'?9908> -> Gen<'?9908 option>
Type parameters: '?9908 Attributes: [<CompiledName("TryFilter")>] |
Tries to generate a value that satisfies a predicate. This function 'gives up' by generating None if the given original generator did not generate any values that satisfied the predicate, after trying to get values by increasing its size. The CompiledName: |
tryWhere predicate generator
Signature: predicate:('a -> bool) -> generator:Gen<'a> -> Gen<'a option>
Type parameters: 'a Attributes: [<CompiledName("TryWhere")>] |
Tries to generate a value that satisfies a predicate. This function 'gives up' by generating None if the given original generator did not generate any values that satisfied the predicate, after trying to get values by increasing its size. The CompiledName: |
two(g)
Signature: g:Gen<'a18> -> Gen<'a18 * 'a18>
Type parameters: 'a18 Attributes: [<CompiledName("Two")>] |
Build a generator that generates a 2-tuple of the values generated by the given generator. CompiledName: |
unzip(g)
Signature: g:Gen<'?9878 * '?9879> -> Gen<'?9878> * Gen<'?9879>
Type parameters: '?9878, '?9879 |
Split a generator of pairs into a pair of generators. |
unzip3(g)
Signature: g:Gen<'?9881 * '?9882 * '?9883> -> Gen<'?9881> * Gen<'?9882> * Gen<'?9883>
Type parameters: '?9881, '?9882, '?9883 |
Split a generator of 3-tuples into a 3-tuple of generators. |
where predicate generator
Signature: predicate:('b -> bool) -> generator:Gen<'b> -> Gen<'b>
Type parameters: 'b Attributes: [<CompiledName("Where")>] |
Generates a value that satisfies a predicate. Contrary to tryWhere, this function keeps re-trying by increasing the size of the original generator ad infinitum. Make sure there is a high probability that the predicate is satisfied. The CompiledName: |
zip f g
Signature: f:Gen<'c> -> g:Gen<'d> -> Gen<'c * 'd>
Type parameters: 'c, 'd |
Combine two generators into a generator of pairs. |
zip3 f g h
Signature: f:Gen<'d> -> g:Gen<'e> -> h:Gen<'f> -> Gen<'d * 'e * 'f>
Type parameters: 'd, 'e, 'f |
Combine three generators into a generator of 3-tuples. |
