相关疑难解决方法(0)

我有以下代码:

val text = "some text goes here"
val (first, rest) = text.splitAt(4)
println(first + " *" + rest)

这很好.

但是,我想有两个案例,在外面定义"first"和"rest",如下所示:

val text = "some text goes here"
var (first, rest) = ("", "")
if (text.contains("z")) {
  (first, rest) = text.splitAt(4)
} else {
  (first, rest) = text.splitAt(7)
}
println(first + " *" + rest)

但这给了我一个错误:

scala>      | <console>:2: error: ';' expected but '=' found.
         (first, rest) = text.splitAt(4)

为什么要做错误(首先,休息)= text.splitAt(4)但不要做val(首先,休息)= text.splitAt(4)？我该怎么办？

编辑:无法重新分配val,更改为var.同样的错误