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Pick a constructor with a given distribution, and fill its fields with recursive calls to arbitrary.

Example

data X = ...
  deriving Arbitrary via (GenericArbitrary '[2, 3, 5] X)

Picks the first constructor with probability 2/10, the second with probability 3/10, the third with probability 5/10.

This newtype does no shrinking. To add generic shrinking, use AndShrinking.

Uses genericArbitrary.

Since: 1.5.0.0

Pick every constructor with equal probability.

This newtype does no shrinking. To add generic shrinking, use AndShrinking.

Uses genericArbitraryU.

Since: 1.5.0.0

arbitrary for types with one constructor. Equivalent to GenericArbitraryU, with a stricter type.

This newtype does no shrinking. To add generic shrinking, use AndShrinking.

Uses genericArbitrarySingle.

Since: 1.5.0.0

Decrease size at every recursive call, but don't do anything different at size 0.

data X = ...
  deriving Arbitrary via (GenericArbitraryRec '[2, 3, 5] X)

N.B.: This replaces the generator for fields of type [t] with listOf' arbitrary instead of listOf arbitrary (i.e., arbitrary for lists).

This newtype does no shrinking. To add generic shrinking, use AndShrinking.

Uses genericArbitraryRec.

Since: 1.5.0.0

GenericArbitrary with explicit generators.

Example

data X = ...
  deriving Arbitrary via (GenericArbitraryG CustomGens '[2, 3, 5] X)

where, for example, custom generators to override String and Int fields might look as follows:

type CustomGens = CustomString :+ CustomInt

Note on multiple matches

Multiple generators may match a given field: the first will be chosen.

This newtype does no shrinking. To add generic shrinking, use AndShrinking.

Uses genericArbitraryG.

Since: 1.5.0.0

GenericArbitraryU with explicit generators. See also GenericArbitraryG.

This newtype does no shrinking. To add generic shrinking, use AndShrinking.

Uses genericArbitraryUG.

Since: 1.5.0.0

genericArbitrarySingle with explicit generators. See also GenericArbitraryG.

This newtype does no shrinking. To add generic shrinking, use AndShrinking.

Uses genericArbitrarySingleG.

Since: 1.5.0.0

genericArbitraryRec with explicit generators. See also genericArbitraryG.

This newtype does no shrinking. To add generic shrinking, use AndShrinking.

Uses genericArbitraryRecG.

Since: 1.5.0.0

General generic generator with custom options.

This newtype does no shrinking. To add generic shrinking, use AndShrinking.

Uses genericArbitraryWith.

Since: 1.5.0.0

Add generic shrinking to a newtype wrapper for Arbitrary, using genericShrink.

data X = ...
  deriving Arbitrary via (GenericArbitrary '[1,2,3] `AndShrinking` X)

Equivalent to:

instance Arbitrary X where
  arbitrary = genericArbitrary (1 % 2 % 3 % ())
  shrink = genericShrink

Since: 1.5.0.0

Since: 1.5.0.0

Since: 1.5.0.0