fact: Fixpoint unlift_env (E': context) (t': type) (E: context) : dcontext (E' ++ t' :: E) -> dcontext (E' ++ E) := match E' with | nil => fun e => snd e | t :: E' => fun e => (fst e, unlift_env E' t' E (snd e)) end.
imports: Coq(Bool String List Program.Equality) CDF(Sequences)