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Come usare Enums in Scala Slick?

Ho risolto il problema con Enums nel modo seguente (prendendo i tuoi valori come esempio):

import play.api.db.slick.DB
import play.api.db.slick.Config.driver.simple._


sealed trait MyEnum
case object MyEnumA extends MyEnum
case object MyEnumB extends MyEnum
case object MyEnumC extends MyEnum

object MyEnumMapper {
  val string_enum_mapping:Map[String,MyEnum] = Map(
     "a" -> MyEnumA,
     "b" -> MyEnumB,
     "c" -> MyEnumC
  )
  val enum_string_mapping:Map[MyEnum,String] = string_enum_mapping.map(_.swap)
  implicit val myEnumStringMapper = MappedTypeMapper.base[MyEnum,String](
    e => enum_string_mapping(e),
    s => string_enum_mapping(s)
  )
}

import MyEnumMapper._

case class MyData(
 ......
 enumValue: MyEnum,
 .....
)

................

object MyDataTable extends Table[MyData]("<table_name>") {
......
def enumValue = column[MyEnum]("<field_name>")
.....

.... /* whatever lifted or direct slick calls you want */ 

}

Se funziona per me sia in Play 2.1 che in Play 2.2, Slick 1.0.0 e MariaDB 5.5 (come MySQL)