sample plugins for discussion

gistfile1.scala

object FooPlugin extends sbt.Plugin {
  val FooConfig = config("foo")
  lazy val fooA    = SettingKey[Int]("foo-a")
  lazy val fooB    = SettingKey[String]("foo-b")
  lazy val fooC    = SettingKey[(Int, String)]("foo-c")
  lazy val fooD    = SettingKey[(Int, String, String)]("foo-d")
  
  lazy val fooJars = TaskKey[Classpath]("foo-jars")
  lazy val fooSomething = TaskKey[Classpath]("foo-something")
  
  lazy val fooSettings: Seq[sbt.Project.Setting[_]] = Seq(
    fooA := 1,
    fooB := "A",
    fooC <<= (fooA, fooB) { (a, b) => (a, b) },
    fooD <<= (fooC) { (c) => (c._1, c._2, "x") },
    fooJars <<= ((dependencyClasspath in Runtime).identity),
    fooSomething <<= fooJars.identity
  )
}

object APlugin extends Plugin {
  object A {
    val a = SettingKey[Int]("a")
  }
}
object BPlugin extends Plugin {
  object B {
    val a = SettingKey[String]("a")
  }
}

sbtobfuscate.scala

package sbtobfuscate

import sbt._
import Keys._

object Plugin extends sbt.Plugin {
  lazy val obfuscate        = TaskKey[File]("obfuscate")
  lazy val obfuscateA       = SettingKey[Int]("obfuscate-a")
  lazy val obfuscateJarName = SettingKey[String]("obfuscate-jar-name")
  
  lazy val obfuscateSettings = Seq(
    sources in obfuscate <<= (sources)  
  )
}