StackOverflow Question

Example.kt

import arrow.core.Nel
import arrow.core.raise.Raise
import arrow.core.raise.recover
import arrow.fx.coroutines.parZipOrAccumulate

object ApplicationError
object UserLegalId
object User
object DepartmentCode
object Department
object AddUserToDepartmentInfo {
  val userLegalId = UserLegalId
  val departmentCode = DepartmentCode
}

context(Raise<ApplicationError>)
suspend fun getUser(legalId: UserLegalId): User = User

context(Raise<ApplicationError>)
suspend fun getDepartment(departmentCode: DepartmentCode): Department = Department

context(Raise<Nel<ApplicationError>>)
suspend fun execute(param: AddUserToDepartmentInfo): Department {
  val pair: Pair<User, Department> =
    parZipOrAccumulate(
      { getUser(param.userLegalId) },
      { getDepartment(param.departmentCode) }
    ) { a, b -> Pair(a, b) }
  return pair.second
}

suspend fun main() {
  recover({
    val res = execute(AddUserToDepartmentInfo)
    println(res)
  }) { error -> println(error) }
}