Goal:
  
  A : Type
  P : nat → A → Type
  x : A
  l : list A
  k : nat
  IHl : Alli (λ k' : nat, P (Nat.pred #|l| - k' + k)) 0 (List.rev l)
  a : Alli P k l
  b : Alli P (#|l| + k) [x]
  ============================
   (Alli ?P 0 (List.rev l))


DEBUG:Going to execute:
<coq-core.plugins.ltac::eauto@0> $1 $2 $3
DEBUG LTAC Evaluated term: (IHl k a)
DEBUG LTAC Evaluated term: Alli_shift
DEBUG LTAC Evaluated term: Alli_impl