fact: Definition Either_ap {E X Y} (f : Either E (X → Y)) (x : Either E X) : Either E Y := match f with | Left e => Left e | Right f' => match x with | Left e => Left e | Right x' => Right (f' x') end end.
imports: Category.Lib Category.Theory.Coq.Functor Category.Theory.Coq.Applicative Category.Theory.Coq.Monad