{z : A} (f : forall i, x i $-> z) : forall i, cat_coprod_rec f $o cat_in i $== f i := cat_prod_beta I (A:=A^op) (x:=x) f.
Require Import Basics.Overture Basics.Tactics Basics.Decidable. Require Import Types.Bool. Require Import WildCat.Core WildCat.Equiv WildCat.Forall WildCat.NatTrans