小编Ska*_*Ska的帖子

这很好地描述了这个问题:

scala> var l2 = List(1,2,3)
l2: List[Int] = List(1, 2, 3)

scala> l2(2) = 55
<console>:10: error: value update is not a member of List[Int]
              l2(2) = 55
              ^