type SeqView[T] = object data: ref seq[T] bounds: Slice[int] proc box[T](x: T): ref T = new(result); result[] = x iterator items[T](sv: SeqView[T]): T = for pos in sv.bounds: yield sv.data[pos] var seq1 = @[1, 2, 3, 4, 5, 6] sv = SeqView[int](data: box(seq1), bounds: 2..4) for el in sv: echo el