Goal:
  
  A : Type
  B : Type
  R : nat → A → B → Type
  n : nat
  b0 : All2i R n [] []
  b'' : nat
  x : A
  y : B
  l : list A
  r : list B
  r0 : R b'' x y
  b : All2i R (S b'') l r
  ============================
   ({| pr1 := {| pr1 := n; pr2 := {| pr1 := []; pr2 := [] |} |}; pr2 := b0 |} =
    {|
      pr1 := {| pr1 := b''; pr2 := {| pr1 := x :: l; pr2 := y :: r |} |};
      pr2 := All2i_cons r0 b
    |}
    → let H := CoreTactics.block in
      NoConfusionHom_All2i A B R n [] [] All2i_nil b0
      → let H0 := CoreTactics.block in All2i_nil = b0)


DEBUG:Going to execute:
simplify * || simplify ?; cbv beta