Definition get_assoc_hor (C : predoublecategory_hor) : ∏ (a b c d : C) (f : a -h-> b) (g : b -h-> c) (h : c -h-> d), f ·h (g ·h h) = (f ·h g) ·h h := pr122 C.
Require Import UniMath.Foundations.Propositions. Require Import UniMath.Foundations.Sets. Require Import UniMath.MoreFoundations.PartA. Require Import UniMath.MoreFoundations.Notations. Require Import UniMath.CategoryTheory.Core.Prelude. Require Import UniMath.CategoryTheory.TwoSidedDisplayedCats.TwoSidedDispCat. Require Import UniMath.CategoryTheory.TwoSidedDisplayedCats.Univalence.