Definition arrow_mor_mor_assoc {C:category} {c c' c'':C} {X:[C^op,HSET]} (g:c''-->c') (f:c'-->c) (x:c⇒X) : x ⟲ (f ∘ g) = (x ⟲ f) ⟲ g := eqtohomot (functor_comp X f g) x.
Require Import UniMath.MoreFoundations.Tactics.