Definition func_tycontext_t_denote :=
forall p t id ty ,  list_norepet (map fst p ++ map fst t ) ->
((make_tycontext_t p t) ! id = Some ty <-> (In (id,ty) p \/ In (id,ty) t)).
Definition func_tycontext_v_denote :=
forall v id ty, list_norepet (map fst v) ->
((make_tycontext_v v) ! id = Some ty <-> In (id,ty) v).

(* Specifications: *)
Lemma func_tycontext_v_sound : func_tycontext_v_denote.
unfold func_tycontext_v_denote. intros.