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:
<coq-core.plugins.ltac::intro@0>