Goal:
    G : t  n : option Z
  ============================
   (match n with
    | Some z => z <=? 0
    | None => false
    end -> exists z : Z, n = Some z /\ z <= 0)


DEBUG:Going to execute:
destruct n

Goals:
    G : t  z : Z
  ============================
   (z <=? 0 -> exists z0 : Z, Some z = Some z0 /\ z0 <= 0)

    G : t
  ============================
   (false -> exists z : Z, None = Some z /\ z <= 0)


DEBUG:Going to execute:
try intuition congruence
DEBUG LTAC Evaluated term: n