liquid-base-4.14.3.0: src/Data/Foldable.spec
module spec Data.Foldable where
import GHC.Base
length :: Data.Foldable.Foldable f => forall a. xs:f a -> {v:Nat | v = len xs}
null :: Data.Foldable.Foldable f => v:(f a) -> {b:Bool | (b <=> len v = 0) && (not b <=> len v > 0)}