在Scala中将for循环转换为while循环

Question

使用while构造编写以下代码的替代方法是什么？

val list = List(1,2,3)                            
for (v <- list) println(v) 

Answer 1

val list = List(1,2,3)  
val iter = list.iterator
while (iter.hasNext) println(iter.next())

Answer 2

可能的强制性遍历：

var current = list
while(!current.isEmpty) {
   println(current.head)
   current = current.tail
}

Answer 3

val list = List(1,2,3)
var i = 0
while (i < list.length) {
  println(list(i))
  i += 1
}