Spark - “sbt package” - “value $不是StringContext的成员” - 缺少Scala插件？ [英] Spark - "sbt package" - "value $ is not a member of StringContext" - Missing Scala plugin?

问题描述

当从一个小型Spark Scala应用程序的命令行运行sbt package时，我在以下代码行中得到value $不是StringContext的成员编译错误：

When running "sbt package" from the command line for a small Spark Scala application, I'm getting the "value $ is not a member of StringContext" compilation error on the following line of code:

val joined = ordered.join(empLogins, $"login" === $"username", "inner")
  .orderBy($"count".desc)
  .select("login", "count")

Intellij 13.1给了我同样的错误信息。在Eclipse 4.4.2中编译相同的.scala源代码没有任何问题。而且它也可以在命令行的单独maven项目中与maven一起使用。

Intellij 13.1 is giving me the same error message. The same .scala source code gets compiled without any issue in Eclipse 4.4.2. And also it works well with maven in a separate maven project from the command line.

看起来sbt无法识别$符号，因为我错过了一些插件在我的project / plugins.sbt文件或build.sbt文件中的某些设置。

It looks like sbt doesn't recognize the $ sign because I'm missing some plugin in my project/plugins.sbt file or some setting in my build.sbt file.

你熟悉这个问题吗？任何指针将不胜感激。如果需要，我可以提供build.sbt和/或project / plugins.sbt。

Are you familiar with this issue? Any pointers will be appreciated. I can provide build.sbt and/or project/plugins.sbt if needed be.

推荐答案

你需要确保你< a href =https://spark.apache.org/docs/1.3.0/api/scala/index.html#org.apache.spark.sql.SQLContext$implicits$> import sqlContext .implicits ._

You need to make sure you import sqlContext.implicits._

这会让你隐式类StringToColumn扩展AnyRef

评论为：

将$col name转换为一栏。

Converts $"col name" into an Column.

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