Goal:
  
  A : Type
  B : Type
  R : nat → A → B → Type
  n : nat
  l0 : list A
  l : list B
  a : All2i R n l0 l
  b : All2i R n l0 l
  e : a = b
  ============================
   (noConfusionHom_All2i_obligation_1 A B R n l0 l a b
      (noConfusionHom_All2i_obligation_2 A B R n l0 l a b e) = e)


DEBUG:Going to execute:
intros; CoreTactics.on_last_hyp ltac:(fun id => destruct id);
            CoreTactics.on_last_hyp
             ltac:(fun id =>
                     CoreTactics.destruct_sigma id; DepElim.depelim id);
            simpl