ZIO is a zero-dependency Scala library for asynchronous and concurrent programming with similar features as Cats IO or Monix.
ZIO — A type-safe, zero-dependency library for asynchronous and concurrent programming in Scala.
Homepage: https://zio.dev/
Questions tagged [zio]
241 questions
3
votes
1 answer
zio, custom Assertion renderer for current value
We have a custom zio.test.Assertion that wrap json-path-assert:
def isJson(matching: org.hamcrest.Matcher[_ >: ReadContext]): Assertion[HttpEntity] = {
def test(entity: => HttpEntity): Boolean = {
// Removed for brevity
}
…
gervais.b
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3
votes
1 answer
ZIO Streams: Which is the difference between a ZSink and a ZTransducer?
I'm studying ZIO Streams, using version 1.0.9 of the library zio-streams.
I cannot find any reference that shows me the difference between a ZSink and a ZTransducer.
What is the difference?
riccardo.cardin
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3
votes
1 answer
Is there a simple way to convert Option[Task[T]] to Task[Option[T]]?
While using monix.eval.Task or zio.Task, is there a simple way to convert Option of Task to Task of Option?
Karthik P
- 481
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- 9
3
votes
0 answers
Scala, ZIO - how to convert Unit into ZIO[Any, Nothing, Unit] after iterating all elements in list?
I have a simple method:
def process(element: SomeData): ZIO[Any, Nothing, Unit]
I would like to use it on every element from list:
def processElements(list: List[SomeData]): ZIO[Any, Nothing, Unit] = {
list.foreach(element =>
…
Developus
- 1,400
- 2
- 14
- 50
3
votes
1 answer
Scala, ZIO - how to convert ZIO to Task and get result?
I have a method which returns some ZIO:
def method(...): ZIO[Any with clock, SomeError, Unit]
The method which calls this return Task[Unit]:
def otherMethod(..): Task[Unit] = {
ZIO.effect(method(...))
}
The problem is when I call it with…
Developus
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3
votes
3 answers
Zio, transform Seq[ZIO] to ZIO[Seq]
That may be a dumb question, but starting with ZIO, I cannot manage to convert a Seq[ZIO] to ZIO[Seq]:
def translate(keys: Seq[String], locales: Seq[Locale]):RIO[Translator, Seq[Translation]] = {
for {
service <- ZIO.environment[Translator]
…
gervais.b
- 2,294
- 2
- 22
- 46
3
votes
1 answer
Fiber on the JVM with Scala IO implementations
My understanding is that IO Implementation like cats-effetcs or Zio use fibers, and this on the JVM.
I wonder what's the underlying lib or framework they are using, if the JVM e.g. 11 does not officially support fibers yet ?
MaatDeamon
- 9,532
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- 127
3
votes
2 answers
Scala, ZIO - convert Future into ZIO or ZIO into Future. Is it possible?
I created two versions of my service. First one uses Futures, other one uses ZIO as an effect.
I have a simple method which use Future as a result effect:
def get(id: String)(implicit executionContext: ExecutionContext): Future[Data]
I also has…
Developus
- 1,400
- 2
- 14
- 50
3
votes
3 answers
Abort early in a fold with ZIO
I wanted to add an answer to abort-early-in-a-fold for ZIO.
So I took the solution with cats: cats solution
def sumEvenNumbers(nums: Stream[Int]): Option[Long] = {
import cats.implicits._
nums.foldM(0L) {
case (acc, c) if c % 2 == 0 =>…
pme
- 14,156
- 3
- 52
- 95
3
votes
1 answer
How to handle an ADT (sealed trait) with ZIO config
How can I add a Configuration Description manually for an Algebraic Data Type with ZIO Conf.
In the examples I found an example on how to handle ADTs with Magnolia.
Is this also possible when adding manually a Description of the…
pme
- 14,156
- 3
- 52
- 95
3
votes
1 answer
Running http4s server with ZIO Env
Trying to learn using ZIO library, so I decided to create a basic web service app. Idea pretty basic, use http4s lib for server and route endpoints, print "hello world" on endpoint call.
With the help of docs and examples I found, produces…
Bublik
- 912
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- 30
3
votes
1 answer
ZIO: Why I get 'An unchecked error was produced.'
I have a misunderstanding with exception handling in ZIO. I followed the ZIO-Documentation.
In a test class I run the following code:
new DefaultRuntime {}.unsafeRun(
(for {
peopleRef <- Ref.make(Vector(People()))
_ <-…
pme
- 14,156
- 3
- 52
- 95
3
votes
1 answer
Scala ZIO Ref datatype
I have one class in Scala with four parameters 2 of them is variable and I wanted to use the Ref data type in Zio to control the access to those variable here is my code :
import zio._
class Rectangle(val width: Int,val height: Int) {
val x:…
NaseemMahasneh
- 485
- 5
- 19
3
votes
2 answers
How do I make a Scalaz ZIO lazy?
I have a heavy side-effecting function (think database call) that I want to use as a lazy value, so that it gets called only on first use (and not at all if never used).
How do I do this with ZIO?
If my program looks like this, the function gets…
Thilo
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2
votes
0 answers
Equivalent looking ZIO future interop code with different results
Working with ZIO for the first time and wrote some code that boiled down to
val x = ZStream.fromIterable(Iterable.empty).runDrain
await(zio.Runtime.default.unsafeRun(x.toFuture))
it compiles but fails at runtime with
[info] …
Sign
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