Goal:
    A : Type  n : nat  hd : A  tl : list A  H : S n < #|hd :: tl|
  ============================
   (n < #|tl|)


DEBUG:Going to execute:
try (solve
            [ red; intros; Tactics.destruct_conjs; Tactics.autoinjections;
               Tactics.discriminates ])
Level 2: Backtrace:

No primitive equality found.
Level 2: Backtrace:

No primitive equality found.
Level 1: Backtrace:

No primitive equality found.
Level 0: Backtrace:

No primitive equality found.