ZIO learning - atomic update like operations / published by https://github.com/dacr/code-examples-manager #0925a4d5-b8d9-4995-8d64-5c241958d83b/137c00b1f185ff128b78ca9255c92806d1c753fa

zio-learning-18-shared-state-ref.sc

// summary : ZIO learning - atomic update like operations
// keywords : scala, zio, learning, pure-functional, @testable
// publish : gist
// authors : David Crosson
// license : Apache License Version 2.0 (https://www.apache.org/licenses/LICENSE-2.0.txt)
// id : 0925a4d5-b8d9-4995-8d64-5c241958d83b
// created-on : 2021-04-06T09:46:48+02:00
// managed-by : https://github.com/dacr/code-examples-manager
// run-with : scala-cli $file

// ---------------------
//> using scala "3.4.2"
//> using dep "dev.zio::zio:2.0.13"
// ---------------------
/*
 inspired from
   - [John A De Goes - ZIO: Next-Generation Effects in Scala](https://www.youtube.com/watch?v=mkSHhsJXjdc)
   - +34:00
 */

import zio.*

object Encapsulated extends ZIOAppDefault {
  def run = {
    // Ref[A] : is a "mutable" cell that contains a reference to an A that may be updated atomically
    for {
      ref         <- Ref.make(0)
      incrementers = List.fill(100)(ref.update(_ + 1))
      _           <- ZIO.foreachPar(incrementers)(identity)
      v           <- ref.get
      _           <- Console.printLine(v)
    } yield v
  }
}

Encapsulated.main(Array.empty)