Section Properties.
Implicit Types x y : TVar.
Implicit Types xs ys : list TVar.
(* ---------------------------------------------------------------------- *)
(** **** Abstract properties of ok *)
(* ---------------------------------------------------------------------- *)
(** **** Properties of binds *)
(* ---------------------------------------------------------------------- *)
(** **** Properties of all_binds *)

(** All_Binds on singular. *)
Theorem all_binds_single_empty : forall A x (v : A),
(x ∶ v) ⊏ (@empty A) ->
False.