madeleine-chercover-hs

def eatVegetable(vegetable: Vegetable): String =
  vegetable match {
    case ChocolateCake(layers, _) if layers > 3 =>
      "Now that's what I call a cake - I mean vegetable."
    case _ =>
      "No, thank you."
  }

madeleine-chercover-hs

def eatVegetable(vegetable: Vegetable): String =
  vegetable match {
    case Pea(colour, isCooked) =>
      s"Oh great, a ${if (isCooked) "uncooked" else "cooked" } $colour pea."
    case Eggplant(colour, _) =>
      s"No matter how I cook this $colour eggplant, it'll still be the blandest vegetable around."
    case ChocolateCake(layers, _) =>
      s"Yum, a $layers-layer chocolate cake – the best vegetable of all."
  }

madeleine-chercover-hs

sealed abstract class Vegetable

case class Pea(colour: String, isCooked: Boolean) extends Vegetable

case class Eggplant(colour: String, weight: Int) extends Vegetable

case class ChocolateCake(layers: Int, isVegetable: Boolean = true) extends Vegetable

madeleine-chercover-hs

def match(x: Int): String = x match {
  case 1 => "one"
  case 2 => "two"
  case _ => "whatever"
}

madeleine-chercover-hs

def validateLatLong(latitude: Double, longitude: Double): Option[(Double, Double)] =
  if (latitude < -90 || latitude > 90 || longitude < -180 || longitude > 180)
    None
  else
    Some((latitude, longitude))

val foo =
  validateLatLong(49, 123) match {
    case Some((latitude, longitude)) => /* Proceed with validated data */
    case None => /* Handle case where no value is returned */

madeleine-chercover-hs

class InvalidLatLongException(latitude: Double, longitude: Double) extends Exception

def validateLatLong(latitude: Double, longitude: Double): Either[InvalidLatLongException, (Double, Double)] =
  if (latitude < -90 || latitude > 90 || longitude < -180 || longitude > 180)
    Left(InvalidLatLongException(latitude, longitude))
  else
    Right((latitude, longitude))

madeleine-chercover-hs

val indexedList: List[(EncryptedMessage, Int)] = encryptedMessages.zipWithIndex

madeleine-chercover-hs

val maybeKeyGroups: Map[Option[Long], List[(EncryptedMessage, Int)]] = 
  indexedList.groupBy { case (message, _) => message.key }

madeleine-chercover-hs

val keyGroups: Map[Long, List[(EncryptedMessage, Int)]] =
  maybeKeyGroups.collect { case (Some(key), messageGroup) => (key, messageGroup) }

madeleine-chercover-hs

val sorted: List[Message] = decryptedIndexedList
  .sortBy { case (_, index) => index }
  .map { case (message, _) => message }