{α : Type u} →
  {x : BEq α} →
    {x_1 : Hashable α} →
      [EquivBEq α] →
        [LawfulHashable α] →
          {β : Type v} → (Std.ExtDHashMap α fun x => β) → α → (Option β → Option β) → Std.ExtDHashMap α fun x => β