End EvalDo.
Section EvalReturn.
Variables (A B : Type).

Lemma try_allocb s1 s2 (v : A) n i (r : cont B) :
(forall x, verify (s1 x) (updi x (nseq n v) :+ i) r) ->
verify (try_s (allocb_s v n) s1 s2) i r.