Scala 中的内部案例 class

Question

我有以下情况class

case class MyClass (LeftHandSide: (Set[String], String), RightHandSide: Double)

所以，我可以执行以下操作

MyClass((Set("yu", "ye"), "bee"), 0.03).filter( x=> x.RightHandSide>4)

我也希望能够按名称调用 LeftHandSide 的部分内容，例如：

case class MyClass (LeftHandSide: (Part1: Set[String], Part2: String), RightHandSide: Double)

然后：

MyClass((Set("yu", "ye"), "bee"), 0.03).filter(x => x.LeftHandSide.Part2 != "bee")

Answer 1

创建一个名为 LeftHandSide 的附加案例 class：

case class LeftHandSide(partOne: Set[String], partTwo: String)

并在 MyClass 中使用它：

case class MyClass(leftHandSide: LeftHandSide, rightHandSide: Double)

然后：

val myClass = MyClass(LeftHandSide(Set("yu", "ye"), "bee"), 0.03)
myClass.leftHandSide.partTwo != "bee"

Internal case class in scala