Goal:
    A : Type  n : nat
  ============================
   (nth_error [] n = None)


DEBUG:Going to execute:
destruct n

Goals:
    A : Type
  ============================
   (nth_error [] 0 = None)

    A : Type  n : nat
  ============================
   (nth_error [] (S n) = None)


DEBUG:Going to execute:
auto
DEBUG LTAC Evaluated term: n

Goals:
    A : Type
  ============================
   (nth_error [] 0 = None)

    A : Type  n : nat
  ============================
   (nth_error [] (S n) = None)


DEBUG:Going to execute:
<coq-core.plugins.ltac::auto@0> $1 $2 $3