rw[Encodable.fintypeArrowEquivFinArrow_fintypeEquivFin (fun i =>
  WType.elim γ (fun x => f x.fst (List.ofFn (fintypeArrowEquivFinArrow x.snd))) (w.get (i.cast hlw.symm)).val)]
case pos.e_a
α : Type u_1
β : α → Type u_2
inst✝⁴ : Primcodable α
inst✝³ : (a : α) → Fintype (β a)
inst✝² : (a : α) → DecidableEq (β a)
inst✝¹ : (a : α) → Primcodable (β a)
inst✝ : PrimrecCard β
σ : Type u_3
γ : Type u_4
f : α → List γ → γ
e s : ℕ
a : α
w : List (SubWType β s)
hlw : w.length = Fintype.card (β a)
⊢ List.ofFn
      (fintypeArrowEquivFinArrow fun b =>
        elim γ (fun x => f x.fst (List.ofFn (fintypeArrowEquivFinArrow x.snd)))
          ↑(w.get (Fin.cast ⋯ (fintypeEquivFin b)))) =
    List.map (elim' γ (fun x => f x.fst (List.ofFn (fintypeArrowEquivFinArrow x.snd))) s) w
case pos.e_a
α : Type u_1
β : α → Type u_2
inst✝⁴ : Primcodable α
inst✝³ : (a : α) → Fintype (β a)
inst✝² : (a : α) → DecidableEq (β a)
inst✝¹ : (a : α) → Primcodable (β a)
inst✝ : PrimrecCard β
σ : Type u_3
γ : Type u_4
f : α → List γ → γ
e s : ℕ
a : α
w : List (SubWType β s)
hlw : w.length = Fintype.card (β a)
⊢ (List.ofFn fun i => elim γ (fun x => f x.fst (List.ofFn (fintypeArrowEquivFinArrow x.snd))) ↑(w.get (Fin.cast ⋯ i))) =
    List.map (elim' γ (fun x => f x.fst (List.ofFn (fintypeArrowEquivFinArrow x.snd))) s) w