rirakkumya

case class Address(zip:List[String])
 
object Addr {
  type 住所 = Address
  type 郵便番号 = String
  def zip:住所 => List[郵便番号] = _.zip
}

List(Address(List("100-0001","100-0002"))) map Addr.zip
  //->List[List[Addr.郵便番号]] = List(List(100-0001, 100-0002))

rirakkumya

List(Address(List("100-0001","100-0002"))) flatMap Addr.zip
  // ->List[Addr.郵便番号] = List(100-0001, 100-0002)

rirakkumya

import TrainOps._
import TrainService._
 
object TrainService {
  type ANSWER = Either[String, List[TrainStatus]]
  trait Train[A] {
    def status(x: A): ANSWER
  }
  case class TrainStatus(name: String, Status: String)
  case class 運行状況(area: String) {