对象在scala中不是值错误 [英] Object is not a value error in scala

问题描述

在尝试在Scala中制作地图时，我收到以下错误消息：对象Map不是值

While trying to make a map in Scala, I receive the following error message: object Map is not a value

代码I '使用如下：

val myStringMap =  Map[String, String]("first" -> "A", "second" -> "B", "third" -> "C")

我很难理解为什么我无法创建这个地图，因为在查看Scala文档后，在我看来，我的代码的语法是正确的。

I am quite puzzled as to why I cannot create this map because after looking at Scala documentation, it seems to me that the syntax of my code is proper.

推荐答案

当您看到错误对象不是值时，通常意味着范围内类型是Java类型 - 您可能正在导入 java.util.Map 范围

When you see the error "object is not a value" this typically means that the in-scope type is a Java type - you probably are importing java.util.Map in scope

scala> Map(1 -> "one")
res0: scala.collection.immutable.Map[Int,java.lang.String] = Map(1 -> one)

但是

scala> import java.util.Map
import java.util.Map

scala> Map(1 -> "one")
<console>:9: error: object Map is not a value
              Map(1 -> "one")
              ^

请记住，在scala中，每个类附带一个（可选）伴侣对象这是一个值。 Java类不是这样。

Remember, in scala each class comes with a (optional) companion object which is a value. This is not true of Java classes.

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