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April 22nd, 2021, ISSUE 375


herding cats - FunctionK

A handy tool to work around the limitations of unavailable higher rank polymorphism.
Eugene Yokota (@eed3si9n)
A ZIO cheatsheet

Note that almost all of these initial examples come from the ZIOnomicon book and the video that I link to later.
Alvin Alexander (@alvinalexander)
Programming in Scala, Fifth Edition

PrePrint PDF update of Programming in Scala is now available. Use code SCALATIMESAPRILPINS5 for 15% off. Offer expires 4/30/2021.
Artima, Inc. (@ArtimaInc)


Dealing with Optional Values

The Scala functional subset consists of using FP functions everywhere in our codebase, plus two additional requirements. In this video, we’ll cover the first.
Julien Truffaut (@TheFpTower)
Best Features of Scala 3 for Scala.js

In the fourth video in the "Let's talk about Scala 3" series, Sébastien Doeraene, the Technical Director of the Scala Center and author of Scala.js, walks us through his top four features of Scala 3 for Scala.js.
Sébastien Doeraene (@sjrdoeraene)


ZIO Meetup SF, April 22nd

Join us on the 22nd of April at 5 pm PST to listen to John A. De Goes speaking about The ZIO of the Future & Girish Kolanthra speaking about Capital One’s Scala Journey.
Ziverge (@zivergetech)
Scala 3 Release Party, April 24th

Be there for the final countdown! A virtual event with free registration. Starts 6:00 PM.
sphere.it (@sphere_it_)
Practical Functional Programming with Typescript workshop, May 5th - 7th

20% off for Scala Times readers!
Matechs, Ziverge
ScalaCon, May 18th - 21st. and Nov. 2nd - 5th

Brought to you by ScalaDays and Scala eXchange, ScalaCon is a series of virtual conferences designed to bring the Scala community closer together.
ScalaCon (@scalacon)
Functional Scala, Dec 2nd

Functional Scala 2021 returns for another year of great talks, familiar and fresh spaces, and positive energy around the power of functional Scala for delivering compelling solutions to the toughest technology problems. Use promo code SCALATIMES10 for a discount for our readers!
Functional Scala (@FunScala2021)


Scala 3.0.0-RC3

Some critical bugs were discovered during the previous release cycle, whose fixes had to be included in 3.0.0 stable. Therefore, we are having RC3 to give the community time to test our fixes.
Metals v0.10.2

This release mainly adds support for Scala 3.0.0-RC3 as well a couple of smaller improvements.

  1. Scala Times Issue #378

    From Highschool to Teaching Scala. Rust for the Seasoned Scala Developer. Bring gRPC payloads and domain models closer with ScalaPB transformations. Flog: a functional logger for Scala. Opaque Type Alias in Scala 3.

  2. Scala Times Issue #377

    Typeclasses in Scala 3. Scala 3 Release Party - find out how it went!. Typelevel Discord migration. Scalabase, May 14th. ScalaCon, May 18th - 21st. and Nov. 2nd - 5th.

  3. Scala Times Issue #376

    Cats Effect 3 - Introduction to Fibers. Bintray to JFrog Artifactory migration status and sbt 1.5.1. Anomaly / outlier detection using isolation forest in Scala. Comparing Concurrent Programming Alternatives. Scala 3: Safer Pattern Matching with Matchable.

  4. Scala Times Issue #375

    A ZIO cheatsheet. Programming in Scala, Fifth Edition. Dealing with Optional Values. Best Features of Scala 3 for Scala.js. ZIO Meetup SF, April 22nd.

  5. Scala Times Issue #374

    Image editing with Monads. Fire-and-Forget in Cats Effect. Programming in Scala, Fifth Edition. Scala 3: Extension Methods. The Scala3 feature I'm most excited about!.

  6. Scala Times Issue #373

    Context is King. How to build an Android app in Scala 2.13. Revisiting Scala Native performance. Scala 3 in sbt 1.5. Programming in Scala, Fifth Edition.

  7. Scala Times Issue #372

    Using Cats Effect Resource in Non-Functional Contexts. Cats Effect · The pure asynchronous runtime for Scala. Figuring out Scala functional programming libraries. Scala 3: Infix Operator Notation. Building a transportation cloud with microservices.

  8. Scala Times Issue #371

    Introducing ZIO Http. Automatic UI generation with Scala 3's type class derivation. Scala is a Maintenance Nightmare. The Tagless Final Pattern in Scala. Scala3-migrate: a tool making it easier to migrate to Scala 3.

  9. Scala Times Issue #370

    The importance of Scala.js. Scala on Android. JDK 16's Top 5 for Scala. Many happy early returns. Zio quick read: Extracting the executor for a service.

  10. Scala Times Special Scala 3 Issue

    Starting with Scala. Programming in Scala, Fifth Edition. Scala 3 Tech Report. Automatically Deriving Typeclass Instances in Scala 3. Starting with Scala 3 macros: a short tutorial.

  11. Scala Times Issue #369

    Tapir serverless: a proof of concept. Writing kubectl plugins with ZIO K8s. The future of Scaladoc. GSoC 2021 Here we come!. Programming in Scala Fifth Edition - New Release for Scala 3.

  12. Scala Times Issue #368

    Scala 3 Tech Report. Tuples bring generic programming to Scala 3. Scala Cats Invariant Functor. Lean for Scala programmers. Structuring Services with ZIO and ZLayer.

  13. Scala Times Issue #367

    The Coralogix Operator: A Tale of ZIO and Kubernetes. Introducing the lihaoyi-scala Github Organization. Why Are Fibers Fast?. Implementing a CountDownLatch (async and dirty). Value Classes in Scala.

  14. Scala Times Issue #366

    GraphQL Overview  -  Part2  -  Libraries. Scala's List has a Secret. Preventing Version Conflicts with versionScheme. Scala 3 Survey: The Conclusion. Upgrade your Tagless Final with Tofu.

  15. Scala Times Issue #365

    Coding Adventures with Party Parrot Game . Scala Cats Contravariant Functors. From First Principles: Why Scala?. Idiomatic Error Handling in Scala. Stop Letting Your Tests “Make” Your Luck.

  16. Scala Times Issue #364

    Why we need yet another Akka Persistence plugin?. Match Types in Scala 3. A Metals Retrospective (Part 1) · Metals. Making the Spark DataFrame composition type safe(r). Type driven API development using Scala and Tapir.

  17. Scala Times Issue #363

    How to Sort Lists in Scala with Tail Recursion. Image editing with Functors. Tail Recursive Functions (in Scala). Algebraic Data Types (ADT) in Scala. Ep 6: Functional error handling with applicative in Scala 3.

  18. Scala Times Issue #362

    5 Blogs for Scala's Birthday. Monocle 3 Roadmap. Higher-kinded data in Scala. Objects and Companions in Scala. Essential Effects, 27th-29th January, Online Event.

  19. Scala Times Issue #361

    Scala 3: Dependent Types, Part II. Configuring and suppressing warnings in Scala. Threading best practices in Cats Effect. Scala 3 Metaprogramming by Example by Adam Warski. What the Functor?.

  20. Scala Times Issue #360

    Scala 3: Dependent Types, Part I. Publish Scala 2 and Scala 3 macros together. Concurrent state machines. Wire Signals - Yet Another Event Streams Library. Scala Love CFP.

  21. Scala Times Issue #359

    Implementing Type classes in Scala 3. Finite-State Machines + FS2 streams: A match made in heaven. Scala Compiler Options, Fatal Warnings and Linting Guide. ZLayers by example. Scala 3 type classes.

  22. Scala Times Issue #358

    VirtusLab’s Scala 3 cooperation update. Scala 3.0.0-M3: developer's preview before RC1. How to Use Thread.sleep Without Blocking on the JVM. New in Scala 3. Scala Love CFP.

  23. Scala Times Issue #357

    Join the Scala Discord Server!. Enforcing Semantic Versioning with sbt-strict-update. Kafka Cron using wix/greyhound. Scala Filesystem Operations (paths, move, copy, list, delete) . Metals 2020 Review.

  24. Scala Times Issue #356

    Scala 3 Developers' Survey. Tapir vs Endpoints4s. Opaque Type Aliases and Open Classes. Akka Platform Guide. Type classes with Scala 2.

  25. Scala Times Issue #355

    Scala 3 Developers' Survey. Four new features of Scala 2.13 releases that you probably missed. Scala 3: Path-Dependent Types, Dependent Methods and Functions. Message-based Parallelism with Actors. IntelliJ Scala Plugin 2020.3 Is Out!.

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