转换不推荐的sbt生成文件

Question

我有这个build.sbt文件，现在不再推荐使用的语法( <<= )。如何更改文件以使其再次工作？我知道有一页记录了这些更改，但我无法正确理解它。

libraryDependencies <<= scalaVersion {
    scala_version => Seq(
          ("org.apache.spark" % "spark-core_2.10" % "1.2.0").
          exclude("org.eclipse.jetty.orbit", "javax.mail.glassfish").
          exclude("org.eclipse.jetty.orbit", "javax.activation").
          exclude("com.esotericsoftware.kryo", "minlog").
          exclude("com.esotericsoftware.minlog", "minlog").
         exclude("commons-beanutils", "commons-beanutils").
          exclude("commons-beanutils", "commons-beanutils-core").
          exclude("commons-logging", "commons-logging").
          exclude("org.slf4j", "jcl-over-slf4j").
          exclude("org.apache.hadoop", "hadoop-yarn-common").
          exclude("org.apache.hadoop", "hadoop-yarn-api").
          exclude("org.eclipse.jetty.orbit", "javax.transaction").
          exclude("org.eclipse.jetty.orbit", "javax.servlet"),
          ("org.apache.spark" %% "spark-graphx" % "1.2.0").
          exclude("org.eclipse.jetty.orbit", "javax.mail.glassfish").
          exclude("org.eclipse.jetty.orbit", "javax.activation").
          exclude("com.esotericsoftware.kryo", "minlog").
          exclude("com.esotericsoftware.minlog", "minlog").
         exclude("commons-beanutils", "commons-beanutils").
          exclude("commons-beanutils", "commons-beanutils-core").
          exclude("commons-logging", "commons-logging").
          exclude("org.slf4j", "jcl-over-slf4j").
          exclude("org.apache.hadoop", "hadoop-yarn-common").
          exclude("org.apache.hadoop", "hadoop-yarn-api").
          exclude("org.eclipse.jetty.orbit", "javax.transaction").
          exclude("org.eclipse.jetty.orbit", "javax.servlet")
        )
}

Answer 1

查看由sbt发出的警告链接到的迁移指南：

[info] Loading global plugins from /.sbt/0.13/plugins
//tmp/build.sbt:3: warning: `<<=` operator is deprecated. Use `key := { x.value }` or `key ~= (old => { newValue })`.
See http://www.scala-sbt.org/0.13/docs/Migrating-from-sbt-012x.html
libraryDependencies <<= scalaVersion {

你可以看到你掉进了最上面的箱子：

使用简单的表达式，例如：

a <<= aTaskDef
b <+= bTaskDef
c <++= cTaskDefs

只要用相应的方法取代它们就足够了：

a := aTaskDef.value
b += bTaskDef.value
c ++= cTaskDefs.value

所以你的aTaskDef是{}之间的一部分

因此，您可以解决您的问题如下：

scalaVersion := "2.11.7"

libraryDependencies := scalaVersion {
    scala_version => Seq(
          ("org.apache.spark" % "spark-core_2.10" % "1.2.0").
          exclude("org.eclipse.jetty.orbit", "javax.mail.glassfish").
          exclude("org.eclipse.jetty.orbit", "javax.activation").
          exclude("com.esotericsoftware.kryo", "minlog").
          exclude("com.esotericsoftware.minlog", "minlog").
         exclude("commons-beanutils", "commons-beanutils").
          exclude("commons-beanutils", "commons-beanutils-core").
          exclude("commons-logging", "commons-logging").
          exclude("org.slf4j", "jcl-over-slf4j").
          exclude("org.apache.hadoop", "hadoop-yarn-common").
          exclude("org.apache.hadoop", "hadoop-yarn-api").
          exclude("org.eclipse.jetty.orbit", "javax.transaction").
          exclude("org.eclipse.jetty.orbit", "javax.servlet"),
          ("org.apache.spark" %% "spark-graphx" % "1.2.0").
          exclude("org.eclipse.jetty.orbit", "javax.mail.glassfish").
          exclude("org.eclipse.jetty.orbit", "javax.activation").
          exclude("com.esotericsoftware.kryo", "minlog").
          exclude("com.esotericsoftware.minlog", "minlog").
         exclude("commons-beanutils", "commons-beanutils").
          exclude("commons-beanutils", "commons-beanutils-core").
          exclude("commons-logging", "commons-logging").
          exclude("org.slf4j", "jcl-over-slf4j").
          exclude("org.apache.hadoop", "hadoop-yarn-common").
          exclude("org.apache.hadoop", "hadoop-yarn-api").
          exclude("org.eclipse.jetty.orbit", "javax.transaction").
          exclude("org.eclipse.jetty.orbit", "javax.servlet")
        )
}.value

你在你的问题中说：

但我不能很好地理解。

你到底不明白什么？如果你能详细说明的话，如果这是我能告诉你更多的事情，它可能会帮助任何面临类似问题的人。