Section eqit_h.
Context {E : Type -> Type} {R1 R2 : Type} (RR : R1 -> R2 -> Prop).
(** [eqit] is a congruence for [itree] constructors. *)

Lemma eqit_Vis b1 b2 {U} (e : E U)
(k1 : U -> itree E R1) (k2 : U -> itree E R2) :
(forall u, eqit RR b1 b2 (k1 u) (k2 u))
<-> eqit RR b1 b2 (Vis e k1) (Vis e k2).