fact: Definition respectful_hetero (A B : Type) (C : A -> Type) (D : B -> Type) (R : A -> B -> Prop) (R' : forall (x : A) (y : B), C x -> D y -> Prop) : (forall x : A, C x) -> (forall x : B, D x) -> Prop := fun f g => forall x y, R x y -> R' x y (f x) (g y).
imports: Coq.Program.Basics Coq.Program.Tactics Coq.Relations.Relation_Definitions Coq.Classes.RelationClasses