Question

是否可以在Scala 2.11.2中确定Seq[A]的类型？

例如：

val fruit = List("apples", "oranges", "pears")
val nums = List(1, 2, 3, 4)

我想打印这样的Seq类型：

scala> def printType[A](xs: Seq[A]): Unit = xs match {
     | case x: List[String] => println("String")
     | case y: List[Int] => println("Int")
     | }

<console>:8: warning: non-variable type argument String in type pattern List[Str
ing] (the underlying of List[String]) is unchecked since it is eliminated by era
sure
       case x: List[String] => println("String")
               ^
<console>:9: warning: non-variable type argument Int in type pattern List[Int] (
the underlying of List[Int]) is unchecked since it is eliminated by erasure
       case y: List[Int] => println("Int")
               ^
<console>:9: warning: unreachable code
       case y: List[Int] => println("Int")
                                   ^
printType: [A](xs: Seq[A])Unit

P.S。我是斯卡拉的新人。

更新

是否有不使用Reflection API的解决方案？

Answer 1

您可以使用类型标记，请参阅此问题的已接受答案，以获取与您自己类似的详细示例：Scala: What is a TypeTag and how do I use it?

如何在没有Reflection API的情况下确定Seq [A]的类型

1 个答案: