composed for comprehension in scala-CodePudding

I have a list of tasks in a for-comprehension:

def main = {
    List("en", "es", "de").foreach(c => execAll(c))
} 

def execAll(country: String): Future[Unit] = {
   for {
      _ <- repo.exec1(country)
      _ <- repo.exec2(country)
      _ <- repo.exec3(country)
      _ <- repo.exec4(country)
      _ <- repo.exec5(country)
   } yield ()
}

The problem now is because I need to execute functions exec4 and exec5 only for "en" and "es" countries. I tried to add the functions in a list of futures by condition (if country == "en" don't add it)

val all = for {
      _ <- repo.exec1(country)
      _ <- repo.exec2(country)
      _ <- repo.exec3(country)
} yield ()

val enOrEsOnly = for {
      _ <- repo.exec4(country)
      _ <- repo.exec5(country)
} yield ()

country match {
    case "de" => all
    case other => all   enOrEsOnly // invalid code
}

Can find a solution using for-comprehension here? Or can just use a list of futures here? I don't need their results. thanks

Or I can just use an if to solve it:

if (country != "de") {
   repo.exec4(country)
   repo.exec5(country)
}

CodePudding user response：

What about replace execAll by:

def execAll(country: String): Future[Unit] = {
   for {
      _ <- repo.exec1(country)
      _ <- repo.exec2(country)
      _ <- repo.exec3(country)
      if country != "de"
      _ <- repo.exec4(country)
      _ <- repo.exec5(country)
   } yield ()
}

CodePudding user response：

I would rather add an extra layer over repo that has the validations, that way your code will be the same, and in that extra layer you would do something like this:

final class Domain(repo: Repository) {
  def exec4(country: String): Future[Unit] =
    country match {
      case "en" | "es" => repo.exec4(country)
      case _ => Future.unit
    }
}