proposition: Lemma BinProductPr1Commutes (a b : C) (P : BinProductCone a b): ∏ (c : C) (f : C⟦c,a⟧) (g : C⟦c,b⟧), BinProductArrow P f g · BinProductPr1 P = f.
proof: Proof. intros c f g. apply (limArrowCommutes P c (ProdCone f g) true). Qed.
imports: UniMath.Foundations.PartD UniMath.Foundations.Propositions UniMath.Foundations.Sets UniMath.MoreFoundations.Tactics UniMath.CategoryTheory.Core.Categories UniMath.CategoryTheory.Limits.Graphs.Colimits UniMath.CategoryTheory.Limits.Graphs.Limits