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Noboxing Scala Compiler plugin

This compiler plugin issues warnings when the scalac compiler adds a box or unbox operation in a @noboxing annotated definition. It requires scala 2.8.0.

Build

Use "sbt package".

Run

You can instruct scalac to pick up your plugin using -Xplugin:path/to/jar, or you can copy the plugin jar to $SCALA_HOME/misc/scala-devel/plugins.

From the project root, type $ scalac -Xplugin:target/scala_2.8.0/noboxing-plugin_2.8.0-1.0.jar -Xplugin-list

You should see:

noboxing - checks for boxing operations
continuations - applies selective cps conversion

Use

In your source code, import ssol.tools.noboxing.noboxing and annotate a class or definition:

import ssol.tools.noboxing.noboxing

class Test {
  def hello(x: String) {
    println("Hello, " + x)
  }

  @noboxing
  def arith(x: List[Int]) = x(0) + x(1)
}

Then run scalac with your plugin $ scalac -Xplugin:target/scala_2.8.0/noboxing-plugin_2.8.0-1.0.jar -cp
target/scala_2.8.0/noboxing-plugin_2.8.0-1.0.jar test.scala

Don't forget to add the jar to your compilation classpath as well.