case pred_const_ X xs | pred_var_ X xs | def_ X xs =>
  congr! 1
  simp only [List.map_eq_map_iff]
  intro x _
  split_ifs <;> tauto
σ σ' : VarName → VarName
X : DefName
xs : List VarName
binders : Finset VarName
h1 : ∀ v ∉ binders, σ v = σ' v
⊢ def_ X (List.map (fun x => if x ∉ binders then σ x else x) xs) =
    def_ X (List.map (fun x => if x ∉ binders then σ' x else x) xs)
no goals