Scala 在同一行声明多个变量，且第一个字符为大写

Question

我试图通过元组赋值来声明变量，例如:

val (hi, bye) = ("hi", "bye")

显然这很好。然而，当第一个字符为大写时，编译器会爆炸并提示这些变量尚未定义。

val (Hi, Bye) = ("hi", "bye")

为什么这不起作用？我运行的是 Scala 2.11。

顺便说一句，这有效(如预期):

val Hi = "hi"
val Bye = "bye"

Answer 1

来自here :

The tuple on the left-hand side is a pattern; names starting with capital letters are treated as constants when occurring inside a pattern. These constants must exist as values in the context. You find the exact semantics in the Scala spec under pattern matching.