Q:

Scala extract value from Future[Seq[T]] into Future[T]

For a given Seq wrapped in a Future, namely for instance
import scala.concurrent._
import ExecutionContext.Implicits.global

val xs = Future { Seq(1,2,3) }

how to extract the first (one only) value in the collection into another Future, namely
Future { 1 }

A:

val xs = Future { Seq(1,2,3) }
val x = xs.map(_.head)

x will be another Future, and xs is still usable, so you can do anything with it.

