List => Product conversion

As.scala

package object As {
  import shapeless._
  import syntax.typeable._
  import syntax.std.traversable._
  import ops.traversable._
  
  implicit def asOps[A](xs: List[A]) = new AsOps(xs)

  final class AsOps[A](xs: List[A]) {
    def as[U](implicit as: As[U]): Option[U] = as.apply(xs)
  }

  trait As[U] {
      type Repr
      def apply(xs: List[Any]): Option[U]
  }

  object As {
    /* not sure about this */
    //def apply[P <: Product, L <: List[_]](implicit as: As[P]): As.Aux[P, as.Repr] = as
    
    type Aux[P <: Product, L <: HList] = As[P] { type Repr = L }

    implicit def provideAs[P <: Product, L <: HList](implicit gen : Generic.Aux[P, L], ty : Typeable[L], fl: FromTraversable[L]): As.Aux[P, L] = new As[P] {
        type Repr = L
        def apply(xs : List[Any]): Option[P] = xs.toHList[L] map (gen.from(_))
    }
  }
}