gistfile1.scala

  object CaseClassToMapStringOfString {
    import shapeless._
    import shapeless.labelled._
    import syntax.singleton._
    import record._
    import ops.record._
    import syntax.singleton._
 
    case class Color(value: String)
    case class ChartOptions(stringOpt: String, intOpt: Int, colorOpt: Color)
 
    private def colorToString(c: Color): String = c.value
 
    object convertToString extends Poly1 {
      implicit def forString[K] = at[String with KeyTag[K, String]](s => field[K](s))
      implicit def forInt[K] = at[FieldType[K, Int]](i => field[K](i.toString))
      implicit def colorToStringMapper[K] =
        at[FieldType[K, Color]](field[K](colorToString _))
    }
 
    val gen = LabelledGeneric[ChartOptions]
    val opt = ChartOptions("one", 2, Color("red"))
 
    val optsRecord = gen.to(opt)
 
    // I really want to convert to toString on type by type basis
    // But once I map here, I seem to be dropping the keys so then I can't invoke toMap
    // Instead of having an HList of FieldTypes, I have an HList of just String
    // shapeless.::[String,shapeless.::[String,shapeless.::[String,shapeless.HNil]]]
    val mappedRec = optsRecord.map(convertToString)
 
    // toMap kind of works here, but now I am just using toString on value which is really just Any.toString
    val globalMap: Map[String, String] = optsRecord.toMap.map {
      case (key, value) =>
        (key.name) -> value.toString
    }
  }