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Version: 2.x

Consuming Streams

import zio._
import zio.Console._
import zio.stream._

val result: Task[Unit] = ZStream.fromIterable(0 to 100).foreach(printLine(_))

Using a Sink​

To consume a stream using ZSink we can pass ZSink to the ZStream#run function:

val sum: UIO[Int] = ZStream(1,2,3).run(ZSink.sum)

Using fold​

The ZStream#fold method executes the fold operation over the stream of values and returns a ZIO effect containing the result:

val s1: ZIO[Any, Nothing, Int] = ZStream(1, 2, 3, 4, 5).runFold(0)(_ + _)
val s2: ZIO[Any, Nothing, Int] = ZStream.iterate(1)(_ + 1).runFoldWhile(0)(_ <= 5)(_ + _)

Using foreach​

Using ZStream#foreach is another way of consuming elements of a stream. It takes a callback of type O => ZIO[R1, E1, Any] which passes each element of a stream to this callback:

ZStream(1, 2, 3).foreach(printLine(_))