Class for generating generic representations of nested case classes

genericNested.scala

import shapeless._  
trait GenericNested[P] {
    type Repr
    def to(p: P): Repr
    def from(o: Repr): P
  }

  class LowPriorityNested {
    type Aux[P, Repr0] = GenericNested[P] { type Repr = Repr0 }
    implicit def base[T] = new GenericNested[T] {
      type Repr = T
      def to(t: T) = t
      def from(t: T) = t
    }
  }
  object GenericNested extends LowPriorityNested  {
    def apply[P](implicit g: GenericNested[P]): GenericNested.Aux[P, g.Repr] = g
    implicit def hNil = new GenericNested[HNil] {
      type Repr = HNil
      def to(t: HNil) = t
      def from(p: HNil) = p
    }
    implicit def hCons[H, H2, T <: HList, T2 <: HList](implicit gh: GenericNested.Aux[H,H2], gt: GenericNested.Aux[T, T2]) = new GenericNested[H::T] {
      type Repr = H2::T2
      def to(l: H::T) = {
        val h::t = l
        gh.to(h)::gt.to(t)
      }
      def from(l: H2::T2) = {
        val h::t = l
        gh.from(h)::gt.from(t)
      }
    }
    implicit def prod[P <: Product, Repr, L](implicit g: Generic.Aux[P, Repr], gn: GenericNested.Aux[Repr,L]) = new GenericNested[P] {
      type Repr = L
      def to(p: P) = gn.to(g.to(p))
      def from(l: L) = {
        g.from(gn.from(l))
      }
    }