Validated

Validated 예제

 

import cats.data._
import cats.syntax.all._

object ValidatedTest {
  def main(args: Array[String]): Unit = {
    val x: ValidatedNel[String, Int] = 1.validNel[String] // 1.valid[NonEmptyList[String]]
    val y: ValidatedNel[String, Int] = 2.validNel[String] // 2.valid[NonEmptyList[String]]
    val e1: ValidatedNel[String, Int] = "error1".invalidNel[Int] // NonEmptyList.of("error1").invalid[Int]
    val e2: ValidatedNel[String, Int] = "error2".invalidNel[Int] // NonEmptyList.of("error2").invalid[Int]

    val validResult: Validated[NonEmptyList[String], Int] = x.combine(y) // Valid(3)
    val validResult2: ValidatedNel[String, Int] = (x, y).mapN(_ + _) // Valid(3) 
    val invalidResult: ValidatedNel[String, Int] = x |+| y |+| e1 |+| e2 // Invalid(NonEmptyList(error1, error2))
    val invalidResult2: ValidatedNel[String, Int] = List(x, y, e1, e2).reduce(_ |+| _) // Invalid(NonEmptyList(error1, error2))
  }
}