डॉक्स से उद्धरण ( http://slick.typesafe.com/doc/1.0.1/lifted-embedding.html#user-defined-functions-and-types ):
// An algebraic data type for booleans
sealed trait Bool
case object True extends Bool
case object False extends Bool
// And a TypeMapper that maps it to Int values 1 and 0
implicit val boolTypeMapper = MappedTypeMapper.base[Bool, Int](
{ b => if(b == True) 1 else 0 }, // map Bool to Int
{ i => if(i == 1) True else False } // map Int to Bool
)
इसे फ़ाइल स्थिति में अनुकूलित करना:
sealed trait FileStatus
case object New extends FileStatus
case object Uploading extends FileStatus
...
implicit val fileStatusTypeMapper = MappedTypeMapper.base[FileStatus, String](
{
case New => "new"
case Uploading => "uploading"
...
},{
case "new" => New
case "uploading" => Uploading
...
}
)
अपडेट करें:
एक और, कम बेमानी, लेकिन संभवतः कम स्पष्ट संस्करण:
sealed trait FileStatus
case object New extends FileStatus
case object Uploading extends FileStatus
...
val statusMap = Map(
New -> "new",
Uploading -> "uploading",
...
)
implicit val fileStatusTypeMapper = MappedTypeMapper.base[FileStatus, String](
statusMap,
statusMap.map(_.swap)
)