proposition: Proposition lens_id_right {s v : C} (f : lens s v) : comp_lens f (identity_lens v) = f.
proof: Proof. use eq_lens ; cbn. - apply id_right. - rewrite !assoc'. rewrite BinProductOfArrowsPr1. rewrite !assoc. rewrite postcompWithBinProductArrow. rewrite id_left, !id_right. refine (_ @ id_left _). apply maponpaths_2. rewrite <- BinProductOfArrows_id. unfold BinProductOfArrows. rewrite !id_right. apply idpath. Qed.
imports: UniMath.Foundations.All UniMath.MoreFoundations.All UniMath.CategoryTheory.Core.Categories UniMath.CategoryTheory.Core.Functors UniMath.CategoryTheory.Core.Isos UniMath.CategoryTheory.Limits.BinProducts UniMath.CategoryTheory.DisplayedCats.Core UniMath.CategoryTheory.DisplayedCats.Isos UniMath.CategoryTheory.DisplayedCats.Constructions UniMath.CategoryTheory.DisplayedCats.Univalence UniMath.CategoryTheory.DisplayedCats.Projection UniMath.CategoryTheory.TwoSidedDisplayedCats.TwoSidedDispCat UniMath.CategoryTheory.TwoSidedDisplayedCats.Isos UniMath.CategoryTheory.TwoSidedDisplayedCats.Strictness UniMath.CategoryTheory.TwoSidedDisplayedCats.Discrete UniMath.CategoryTheory.TwoSidedDisplayedCats.Univalence UniMath.CategoryTheory.TwoSidedDisplayedCats.Total UniMath.CategoryTheory.TwoSidedDisplayedCats.Examples.FiberwiseProduct UniMath.CategoryTheory.TwoSidedDisplayedCats.Examples.DispCatOnTwoSidedDispCat