Scala Option object inside another Option object

Question

I have a model, which has some Option fields, which contain another Option fields. For example:

case class First(second: Option[Second], name: Option[String])
ca         


        

Answer 1

This can be done by chaining calls to flatMap:

def getN(first: Option[First]): Option[Int] =
  first flatMap (_.second) flatMap (_.third) flatMap (_.numberOfSmth)

You can also do this with a for-comprehension, but it's more verbose as it forces you to name each intermediate value:

def getN(first: Option[First]): Option[Int] =
  for {
    f <- first
    s <- f.second
    t <- s.third
    n <- t.numberOfSmth
  } yield n