Jacoby6000

case class Foo(a: Int, b: String, c: Bar)
case class Bar(x: Int, y: Baz)
case class Baz(z: String)

// Each case class can be generalized in to a product, where that product is just the parts of the case class

// Foo === Int :: String :: Bar :: HNil
// Bar === Int :: Baz :: HNil
// Baz === String :: HNil

Jacoby6000

case class IO[A](unsafePerformIO: () => A) {
  def map[B](ab: A => B): IO[B] = IO(() => ab(unsafePerformIO()))
  def flatMap[B](afb: A => IO[B]): IO[B] =IO(() => afb(unsafePerformIO()).unsafePerformIO())
  def tryIO(ta: Throwable => A): IO[A] = 
    val attempt = IO(() => IO.tryIO(unsafePerformIO()) // lift IO[A] to IO[Either[Throwable,A]] 
    attempt.unsafePerformIO() match {
      case Left(t) => ta(t)
      case Right(a) => a
    })
}

Jacoby6000

sealed trait Foo[A]
case class Bar[A](a: A) extends Foo[A]
case class Baz[A](s: String) extends Foo[A]
case class Woozle[A](foo: Foo[A]) extends Foo[A]

Jacoby6000

sealed trait Foo
case class Bar(a: Int) extends Foo
case class Baz(b: String) extends Foo

val barCodec: Codec[Bar] = ???
val bazCodec: Codec[Baz] = ???

val fooCodec: Codec[Foo] = 
  discriminated[Foo]
    .by(uint32)

Jacoby6000

  case class Path(path: String) extends AnyVal

  trait QueryValue[U, A] {
    def param(u: U): A
    def function(path: Path, args: List[A]): A
    def nul: A

  }

  trait QueryComparison[U, A] {

Jacoby6000

sealed trait QueryValue[A]
case class Parameter[A](value: A) extends QueryValue[A]
case class Function[A](path: Path, args: List[QueryValue[A]]) extends QueryValue[A]
case class Null[A]() extends QueryValue[A]

sealed trait QueryComparison[A]
case class QueryEqual[A](left: QueryValue[A], right: QueryValue[A]) extends QueryComparison[A]
case class QueryGreaterThan[A](left: QueryValue[A], right: QueryValue[A]) extends QueryComparison[A]
case class QueryGreaterThanOrEqual[A](left: QueryValue[A], right: QueryValue[A]) extends QueryComparison[A]

Jacoby6000

                 id                  |                                name                                 |                       album                        |               artist               |  year
--------------------------------------+---------------------------------------------------------------------+----------------------------------------------------+------------------------------------+---------
 ebada1a7-fe44-48a6-b5af-178a6b74a88c | China Town                                                          | Revenge Of Shinobi                                 | Yuzo Koshiro                       | 1989
 c4f5fe57-e761-40eb-93ed-91df1adcf249 | Sugar Sweet Nightmare                                               | Bakemonogatari: Ongaku Zenshuu Songs & Soundtracks | Yui Horie                          | 2011
 dac75046-fee7-4416-a9f3-c892f72da44c | Hidamari no Uta (ft. Hatsune Miku)                                  | Solitude Freak                                     | Yuyoyuppe                          | 

Jacoby6000

case class Foo(a: Int)

implicit val fooMeta: Meta[Foo] = valueClassMeta[Foo].apply

private def valueClassMeta[A]: PartiallyAppliedValueClassMeta[A] = new PartiallyAppliedValueClassMeta[A]

private class PartiallyAppliedValueClassMeta[A] {
  def apply[L <: HList, S](
    implicit ev: Generic.Aux[A, L],
    toL: (S :: HNil) =:= L,

Jacoby6000

 (uuid.successNel[CannotSaveSongError] |@|
  section.lookupOneOf(songNameKeys).map(SongName(_)).toSuccess(MissingKey(songSection, songNameKeys)).toValidationNel |@|
  section.lookupOneOf(artistKeys).map(Artist(_)).successNel |@|
  section.lookupOneOf(albumKeys).map(Album(_)).successNel |@|
  section.lookupOneOf(genreKeys).map(Genre(_)).successNel |@|
  section.lookupOneOf(charterKeys).map(Charter(_)).successNel |@|
  section.lookupOneOf(yearKeys).map(Year(_)).successNel |@|
  now.successNel |@|
  now.successNel)(Song.apply _)

Jacoby6000

 object instances {
  implicit val accessTokenDbIdentifiable: DbIdentifiable.Aux[AccessToken, AccessTokens] = 
    new DbIdentifiable.Aux[AccessToken, AcessTokens] {
      val table = TableQuery[AccessTokens]
      def getDbId(accessToken: AccessToken): Long = AccessToken
      def withItemId(item: AccessToken, id: Long): AccessToken = item.copy(id = Option(id))
    }

  implicit val characterDbIdentifiable: DbIdentifiable.Aux[Character, Characters] = 
    new DbIdentifiable.Aux[Character, Characters] {