PropCheck.such_that_maybe

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such_that_maybe(binding, condition)

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Equivalent to the such_that macro, but the constraint condition is considered non-strict: if the :constraint_tries limit is reached, the generator will just return an instance of type instead of failing, even if that instance doesn't satisfy the constraint.

iex> use PropCheck
iex> even = such_that_maybe n <- nat(), when: rem(n, 2) == 0
iex> quickcheck(
...>   forall n <- even do
...>     rem(n, 2) == 0
...>   end)
true