Scala Compiler Plugin DivByZero Example

The code contained in this repository is based upon Lex Spoon's Scala Compiler Plugin Tutorial, built against scala 2.9.1 and snapshots of unreleased scala 2.10.0.

How to build

Download the sbt-extras sbt runner and run

  $ sbt package

When this completes, the packaged compiler plugin (for 2.9.1-1) can be found at target/scala-2.9.1/scalac-divbyzero-plugin_2.9.1-1.0.jar. Test it in the Scala REPL:

$ scala -Xplugin:target/scala-2.9.1/scalac-divbyzero-plugin_2.9.1-1.0.jar

Welcome to Scala version 2.9.1-1 (Java HotSpot(TM) 64-Bit Server VM, Java 1.6.0_29).
Type in expressions to have them evaluated.
Type :help for more information.

scala> def f = 1 / 0
<console>:7: error: definitely division by zero
       def f = 1 / 0
                 ^

Compare this to when the plugin is not used, where the code compiles without warning and throws an exception when run:

scala> def f = 1 / 0
f: Int

scala> f
java.lang.ArithmeticException: / by zero
at .f(<console>:7)	...

In order to build the plugin for all supported versions of scala, run

$ sbt +package