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3.12.1 The Pick Datatype
Pick
pick-none
pick-some
is-pick-none
is-pick-some

3.12 pick

Usage:
include pick
import pick as ...

3.12.1 The Pick Datatype

data Pick<a, b>:
| pick-none
| pick-some(elt :: a, rest :: b)
end

pick-none :: Pick<a, b>

pick-some :: (elt :: a, rest :: b) -> Pick<a, b>

is-pick-none :: (val :: Any) -> Boolean

is-pick-some :: (val :: Any) -> Boolean