Scala List Flatten

Do you remember the map, from few SKBs ago ?

As a reminder, map allows you to transform a List[A] into a List[B].

What will happen if B is a List as well ?

flatten allows you to turn a List[List[A]] into a List[A].

Try to experiment with other containers such as Option we saw in the past.

What happen if you do

val a: Option[Int] = Some(12)

val aa: Option[Option[Int]] = => Some(x))

val flattenA: Option[Int] = aa.flatten

Reveal more information and clues
Load Exercise