effect

import arrow.core.Either
import arrow.core.None
import arrow.core.Option
import arrow.core.Validated
import arrow.core.continuations.effect
import io.kotest.assertions.fail
import io.kotest.matchers.shouldBe

suspend fun main() {
  effect<String, Int> {
    val x = Either.Right(1).bind()
    val y = Validated.Valid(2).bind()
    val z = Option(3).bind { "Option was empty" }
    x + y + z
  }.fold({ fail("Shift can never be the result") }, { it shouldBe 6 })

  effect<String, Int> {
    val x = Either.Right(1).bind()
    val y = Validated.Valid(2).bind()
    val z: Int = None.bind { "Option was empty" }
    x + y + z
  }.fold({ it shouldBe "Option was empty" }, { fail("Int can never be the result") })
}