∀ {m : Type u_1 → Type u_2} {α : Type u_3} {α_1 : Type u_1} {init : α_1} {f : α → α_1 → m (ForInStep α_1)}
  [inst : Monad m] [LawfulMonad m] {t : Batteries.RBNode α}, forIn t init f = forIn t.toList init f