fact: Definition _ex1 {a : Type} {P : a -> Prop} : Getter { x : a | P x } a := fun _ _ _ f s => fmap (const s) (f (proj1_sig s)).
imports: Hask.Prelude Hask.Control.Monad Hask.Data.Functor.Contravariant Hask.Data.Functor.Identity