gistfile1.txt

package app.models.world

import java.util.UUID

import shapeless._
import shapeless.ops.record.Selector
import shapeless.record._

case class Vect2(x: Int, y: Int)
case class Bounds(position: Vect2, size: Vect2)

object WObject {
  type Id = UUID
  def newId: Id = UUID.randomUUID()

  object Fields {
    object id extends FieldOf[Id]
    object position extends FieldOf[Vect2]

    case class all[L <: HList](implicit
      _id: Selector[L, id.type], _position: Selector[L, position.type]
    )
    object all {
      implicit def make[L <: HList](implicit
        _id: Selector[L, id.type],
        _position: Selector[L, position.type]
      ) = all[L]
    }
  }
}
import WObject._

/* World object */
abstract class WObject[L <: HList](val props: L)(implicit sel: Fields.all[L]) {
  def this(id: WObject.Id, position: Vect2) =
    this(Fields.id ->> id :: Fields.position ->> position :: HNil)

  def id = props(Fields.id)
  def position = props(Fields.position)

  lazy val bounds = Bounds(position, Vect2(1, 1))
}