Definition double_hor_comp {C : category} {D : twosided_disp_cat C C} (Cm : hor_comp_data D) {x y z : C} (h₁ : D x y) (h₂ : D y z) : D x z := pr1 Cm x y z h₁ h₂.
Require Import UniMath.Foundations.All. Require Import UniMath.MoreFoundations.All. Require Import UniMath.CategoryTheory.Core.Categories. Require Import UniMath.CategoryTheory.Core.Isos. Require Import UniMath.CategoryTheory.TwoSidedDisplayedCats.TwoSidedDispCat. Require Import UniMath.CategoryTheory.TwoSidedDisplayedCats.Isos.