以循环方式移动序列的最佳实践？内容来源于 Stack Overflow，并遵循CC BY-SA 3.0许可协议进行翻译与使用

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``````Original sequence: 1 2 3 4 5

Forwarded once: 5 1 2 3 4
Forwarded twice: 4 5 1 2 3
``````

示例代码

``````class RingBuffer[A](val index: Int, val data: IndexedSeq[A]) extends IndexedSeq[A] {
def shiftLeft = new RingBuffer((index + 1) % data.size, data)
def shiftRight = new RingBuffer((index + data.size - 1) % data.size, data)
def length = data.length
def apply(i: Int) = data((index + i) % data.size)
}

val rb = new RingBuffer(0, IndexedSeq(2,3,5,7,11))

println("plain: " + rb)
println("sl: " + rb.shiftLeft)
println("sr: " + rb.shiftRight)
``````

输出

``````plain: Main(2, 3, 5, 7, 11)
sl: Main(3, 5, 7, 11, 2)
sr: Main(11, 2, 3, 5, 7)
``````

```scala> val l = List(1,2,3,4,5)
l: List[Int] = List(1, 2, 3, 4, 5)

scala> val reorderings = Stream.continually(l.reverse).flatten.sliding(l.size).map(_.reverse)
reorderings: Iterator[scala.collection.immutable.Stream[Int]] = non-empty iterator

scala> reorderings.take(5).foreach(x => println(x.toList))
List(1, 2, 3, 4, 5)
List(5, 1, 2, 3, 4)
List(4, 5, 1, 2, 3)
List(3, 4, 5, 1, 2)
List(2, 3, 4, 5, 1)```