combine

Combine several sources, using a given strategy such as merge or concat, into one source.

Signature

def combine[T, U](first: Source[T, _], second: Source[T, _], rest: Source[T, _]*)(strategy: Int => Graph[UniformFanInShape[T, U], NotUsed]): Source[U, NotUsed]
def combine[T, U](first: Source[T, _], second: Source[T, _], rest: Source[T, _]*)(strategy: Int => Graph[UniformFanInShape[T, U], NotUsed]): Source[U, NotUsed]
def combineMat[T, U, M1, M2, M](first: Source[T, M1], second: Source[T, M2])(strategy: Int => Graph[UniformFanInShape[T, U], NotUsed])(matF: (M1, M2) => M): Source[U, M]

Description

emits when there is demand, but depending on the strategy

completes when all sources has completed

Examples

Scala

sourceimport akka.stream._

val sources = immutable.Seq(Source(List(1, 2, 3)), Source(List(10, 20, 30)))

Source
  .combine(sources(0), sources(1))(Concat(_))
  .runWith(Sink.seq)
  // This will produce the Seq(1, 2, 3, 10, 20, 30)