Goal:
  
  A : Type
  P : nat → A → Type
  x : A
  tl : list A
  n0 : nat
  p : P n0 x
  HPl : Alli P (S n0) tl
  IHHPl : ∀ n : nat, nth_error tl n = Some x → P (S n0 + n) x
  ============================
   (P (n0 + 0) x)


DEBUG:Going to execute:
rewrite Nat.add_0_r
DEBUG LTAC Evaluated term: n