{α : Type u_1} →
  {x : BEq α} →
    {x_1 : Hashable α} →
      {m : Type (max u_2 u_1) → Type u_3} →
        {β : Type (max u_2 u_1)} →
          [Monad m] → (α → β → β → m β) → Batteries.HashMap α β → Batteries.HashMap α β → m (Batteries.HashMap α β)