proposition: Lemma whisker_left_on_comp {C : prebicategory} {a b c : C} (f : a -1-> b) {g h i : b -1-> c} (alpha : g -2-> h) (alpha' : h -2-> i) : whisker_left f (alpha ;v; alpha') = whisker_left f alpha ;v; whisker_left f alpha'.
proof: Proof. unfold whisker_left. intermediate_path ((identity f;v; identity f);h;(alpha;v;alpha')). rewrite id_left. reflexivity. now apply interchange. Defined.
imports: UniMath.Foundations.PartD UniMath.MoreFoundations.Tactics UniMath.CategoryTheory.Core.Categories UniMath.CategoryTheory.Core.Isos UniMath.CategoryTheory.Core.NaturalTransformations UniMath.CategoryTheory.Core.Univalence UniMath.CategoryTheory.Core.Functors UniMath.CategoryTheory.PrecategoryBinProduct UniMath.CategoryTheory.Categories.StandardCategories UniMath.CategoryTheory.HorizontalComposition UniMath.CategoryTheory.Equivalences.Core UniMath.Bicategories.WkCatEnrichment.prebicategory UniMath.Bicategories.WkCatEnrichment.Notations