Depend on Scala modules like a pro
Scala
Latest commit eef3690 May 27, 2016 @retronym retronym Merge pull request #6 from NightRa/patch-1
Update Plugin & Scala versions

README.md

Depend on Scala modules like a pro

Two sample projects (Sbt and Maven) which demonstrate recommended configuration for projects that depend on newly spawned scala modules:

  • scala-xml for all classes that live in scala.xml package
  • scala-parser-combinators for all classes that live in scala.util.parsing package
  • scala-swing that has been brought into line with the rest of modules and changed its Maven group id

Sbt sample

This sample demonstrates how to conditionally depend on all modules. If use only on some of the modules just edit the libraryDependencies definition accordingly. If you are just looking for a copy&paste snippet for your build.sbt file, here it is:

// add scala-xml dependency when needed (for Scala 2.11 and newer) in a robust way
// this mechanism supports cross-version publishing
// taken from: http://github.com/scala/scala-module-dependency-sample
libraryDependencies := {
  CrossVersion.partialVersion(scalaVersion.value) match {
    // if scala 2.11+ is used, add dependency on scala-xml module
    case Some((2, scalaMajor)) if scalaMajor >= 11 =>
      libraryDependencies.value ++ Seq(
        "org.scala-lang.modules" %% "scala-xml" % "1.0.3",
        "org.scala-lang.modules" %% "scala-parser-combinators" % "1.0.3",
        "org.scala-lang.modules" %% "scala-swing" % "1.0.1")
    case _ =>
      // or just libraryDependencies.value if you don't depend on scala-swing
      libraryDependencies.value :+ "org.scala-lang" % "scala-swing" % scalaVersion.value
  }
}

Maven sample

This to depend on scala-xml module with assumption that you have scalaBinaryVersion property defined in your pom.xml file. The scalaBinaryVersion should be set to 2.11 for Scala 2.11.0. If you are just looking for copy&paste snippet for your pom.xml file, here it is:

<!-- taken from: http://github.com/scala/scala-module-dependency-sample -->
<dependency>
  <groupId>org.scala-lang.modules</groupId>
  <artifactId>scala-xml_${scalaBinaryVersion}</artifactId>
  <version>1.0.3</version>
</dependency>
<dependency>
  <groupId>org.scala-lang.modules</groupId>
  <artifactId>scala-parser-combinators_${scalaBinaryVersion}</artifactId>
  <version>1.0.3</version>
</dependency>
<dependency>
  <groupId>org.scala-lang.modules</groupId>
  <artifactId>scala-swing_${scalaBinaryVersion}</artifactId>
  <version>1.0.1</version>
</dependency>

NOTE: Due to an issue in Scala compiler a project that uses scala-xml will compile successfully on Scala 2.11, even without an explicit dependency on the scala-xml module. However, it will fail at runtime due to missing dependency. In order to prevent that mistake we offer a workaround. Add -nobootcp Scala compiler option which will make scala-xml invisible to compilation classpath and your code will fail to compile when the dependency on scala-xml is missing. Check sample pom.xml for details.

Scala cross-versioning with Maven

The snippet provided above allows you to declare dependencies on modules shipped against Scala 2.11. If you would like to support building your project with both Scala 2.10 and 2.11 at the same time you'll need to use Maven profiles. Check the pom.xml file in the sample project for details how to set up Maven profiles for supporting different Scala versions.