proposition: Lemma pre_comp_with_iso_is_inj {C : precategory_data} (a b c : ob C) (f : a --> b) (H : is_iso f) (g h : b --> c) : f · g = f · h -> g = h.
proof: Proof. intro X. apply (invmaponpathsweq (make_weq (precomp_with f) (H _ ))). apply X. Qed.
imports: UniMath.Foundations.PartA UniMath.Foundations.Propositions UniMath.Foundations.Sets UniMath.MoreFoundations.Tactics UniMath.CategoryTheory.Core.Categories