Goal:
  
  A : Type
  P : list A → A → Type
  e : NoConfusionHom_All_fold A P [] (All_fold_nil P) (All_fold_nil P)
  ============================
   (let H := CoreTactics.block in
    noConfusionHom_All_fold_obligation_2 A P [] (All_fold_nil P)
      (All_fold_nil P)
      (noConfusionHom_All_fold_obligation_1 A P [] 
         (All_fold_nil P) (All_fold_nil P) e) = e)


DEBUG:Going to execute:
CoreTactics.intros_until_block