Extractor object generation

gistfile1.scala

/**
 * Created by arneball on 2014-06-14.
 */
object ExtractorTest extends App with Integral.ExtraImplicits{
  @extract def longString(str: String) = str.length > 1

  @extract def cool(int: Int) = Option(int).filter{ 2 < _ }.map{ 2 * }

  @extract def evensum[T : Integral](l: List[T]) = {
    l.sum % implicitly[Integral[T]].fromInt(2) == 0
  }

  List(2, 2, 2) match {
    case evensum() => println("even sum! :) ")
  }
  
  "" match {
    case longString() => println("hurray")
    case _ => println("fail")
  }

  3 match {
    case cool(that) => println(that)
    case that => println(that)
  }

}

gistfile2.scala

import scala.annotation.StaticAnnotation
import scala.reflect.macros.blackbox.Context
import language.experimental.macros
/**
 * Created by arneball on 2014-06-14.
 */
class extract extends StaticAnnotation {
  def macroTransform(annottees: Any*) = macro ex.impl
}
object ex {
  def impl(c: Context)(annottees: c.Expr[Any]*): c.Expr[Any] = {
    import c.universe._
    annottees.head.tree match {
      case q"def $name[..$tp](...$param): $ret = $body" =>
        val (h::r1) :: r2 = param
        c.Expr[Any]{
          q"""
          object $name {
            def unapply[..$tp]($h)(...${r1 :: r2}): $ret = $body
           }
          """
        }
      case _ => c.abort(c.enclosingPosition, "must be a method with 1 parameter")
    }
  }
}