proposition: Lemma transport_source_precompose {C : precategory} {x y z w : ob C} (f : x --> y) (g : y --> z) (e : x = w) : transportf (λ x' : ob C, precategory_morphisms x' z) e (f · g) = transportf (λ x' : ob C, precategory_morphisms x' y) e f · g.
proof: Proof. induction e. apply idpath. Qed.
imports: UniMath.Foundations.PartA UniMath.Foundations.UnivalenceAxiom UniMath.MoreFoundations.Tactics UniMath.CategoryTheory.Core.Categories UniMath.CategoryTheory.Core.Isos