Dumonad

Dumonad is a solution to ease of using monad in Scala projects with introducing a set of extension methods.

KISS your code with Dumonad!

Reactive programming become more and more popular nowadays. A common response of a reactive call is a nested monad( i.e Future[Either[L,R]] or Future[Option[T]])

All scala developers know what are map, flatmap, and flatten

The shortest way of chaining two FutureEither using standard Scala API will be something like this:

def firstCall: Future[Either[String, String]]
def secondCall(param: String): Future[Either[String, String]]

val result: Future[Either[String, String]] = firstCall.flatMap {
  case Right(value) => secondCall(value)
  case left => Future.successful(left)
}

While using Dumonad it will be easier empowered with dumap:

def firstCall: Future[Either[String, String]]
def secondCall(param: String): Future[Either[String, String]]

val result: Future[Either[String, String]] = firstCall.dumap(secondCall)

Another thing is changing the order of monad wrappers.
Developers usually use boilerplate codes to do this. For example:

val optionOfFuture: Option[Future[String]]

val futureOfOption: Future[Option[String]] = optionOfFuture match {
  case Some(future) => future.map(Some(_))
  case _ => Future.successful(None)
}

With dummed method it will be a piece of cake, because in Dumonad Future is always the outer wrapper.

val optionOfFuture: Option[Future[String]]

val futureOfOption: Future[Option[String]] = optionOfFuture.dummed