Macro for Adding Mixin to Classes

gistfile1.scala

//SomeTraits.scala
trait Foo {
  def someNumbers: List[Int]

  def getNumbers : List[Int] = someNumbers
}

trait FilteredFoo extends Foo {
  def numberFilter : Int => Boolean

  override def getNumbers : List[Int] = super.getNumbers.filter(numberFilter)
}


//SomeMacros.scala
import language.experimental.macros
import scala.reflect.macros.Context

object FilteredFooMacro {
  def toFilteredFoo[T <: Foo](instance: T, filter: Int => Boolean): T with FilteredFoo = macro impl[T]

  def impl[T: c.WeakTypeTag](c: Context)(instance: c.Expr[T], filter: c.Expr[Int => Boolean]) = {
    //????
  }
}

//SomeClasses.scala
class A extends Foo {
  val someNumbers = List(1,2,3,4)
}

class B extends Foo {
  val someNumbers = List(2,4,6,8)
}

//Test.scala
object Test {
  def test() {
    val a = new A
    val b = new B

    println(toFilteredFoo(a, x => x % 2 == 0).getNumbers)
    println(toFilteredFoo(b, x => x % 2 == 0).getNumbers)
  }
}