(** We add [uniq_from_wf_env] as a hint here since it helps blur the distinction between [wf_env] and [uniq] in proofs.  The lemmas in the MetatheoryEnv library use [uniq], whereas here we naturally have (or can easily show) the stronger [wf_env].  Thus, [uniq_from_wf_env] serves as a bridge that allows us to use the environments library. *)
Hint Resolve uniq_from_wf_env.

Lemma wf_typ_from_binds_typ : forall x U E,
wf_env E ->
binds x (bind_typ U) E ->
wf_typ E U.