Goal:
  
  A : Type
  P : list A → A → Type
  b : All_fold P []
  b0 := {| pr1 := []; pr2 := b |}
     : sigma (λ index : list A, All_fold P index)
  ============================
   (∀ (H := CoreTactics.block) (e : NoConfusionHom_All_fold A P []
                                      (All_fold_nil P) b),
      let H0 := CoreTactics.block in
      noConfusionHom_All_fold_obligation_2 A P [] 
        (All_fold_nil P) b
        (noConfusionHom_All_fold_obligation_1 A P [] (All_fold_nil P) b e) =
      e)


DEBUG:Going to execute:
hnf in (type of id')