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January 3rd, 2019, ISSUE 255


ADT through the looking glass - lenses, prims and other optics

If you have a nested structure and need to update something deep, deep inside.
Mateusz Kubuszok (@MateuszKubuszok)
Hpc with scala and akka Actors

In this brief article I will show you how to accelerate the computation of the Mandelbrot set using akka actors in scala (running on aws with 16 vCPU).
Dario Balinzo (@Dariobalinzo)
Scala Type Classes - The Name Printer

An example to show the why and how of type classes.
Nicolas A Perez (@anicolaspp)
Evolutionary Algorithms on the JVM via Scala  -  a minimal introduction

Discover helisa - an elegant Scala library using jenetics as its backend.
Mikołaj Koziarkiewicz (@mikolak_net)
Aecor - Purely functional event sourcing in Scala. Part 4a

Today we’re going to build an eventsourced view with the help of Aecor and discuss CQRS in the context of eventsourcing.
Vladimir Pavkin (@vlpavkin)
Compact, Streaming Pretty-Printing of Hierarchical Data

This blog post extracts the core pretty-printing algorithm, separates it out from all the incidental concerns and documents it it for posterity.
Li Haoyi (@li_haoyi)
Taming cats - State

If you are encumbered with mutable variables, give State a try. It will make your code cleaner, and safer.
Philippe Vinchon
Type safety and Spark Datasets in Scala

Apart from the type safety, I also wanted to share how Shapeless (and really generic type-level programming) can aid in writing succinct, compile-time and type-safe code and I hope I was able to do some justice to how awesome Shapeless and Frameless (for Spark Dataset) are!
Manish Katoch
Akka server logging with Slf4j/Logback in Google Cloud Platform

After deployment of service to Google Cloud Platform, we would like to bring in proper logging & monitoring.
Linda Hong
Fast typechecked markdown documentation with clear error messages

This post introduces how mdoc evaluates Scala code examples with good performance while reporting clear error messages. mdoc is a markdown documentation tool inspired by tut.
Ólafur Páll Geirsson (@olafurpg)
Scala Methods - Syntax, Declaration, Use case, Examples - Leo Benkel

A method, sometimes called a function, in computer programming, is a black box which takes input(s), executes one or more operations, and finally yields an output value.
Leo Benkel (@LeoBenkel)


Homegrown Scala Collections - Part 19 - Tail Recursion with CPS

In this video we will attempt to eliminate tail calls with CPS.
DevInsideYou (@DevInsideYou)


Scalar, Warsaw, Poland April 5-6, 2019

Join the next edition of the largest Scala conference in central Europe!
SoftwareMill (@softwaremill)
Lambda Days, Kraków, Poland, February 21-22, 2019

Use promo code SCALArlz10 for a 10% discount for our readers!
LambdaDays (@LambdaDays)



Code samples of advanced features of Http4s in combination with some features of Fs2 not often seen.
Gabriel Volpe (@volpegabriel87)

A semiaquatic animal with venomous ankles, welding a Vault client in Scala.
Timothy Perrett (@timperrett)


January: Union Types

Taking Miles' original idea further.
James Phillips
February: The Advantages Of Scala

No language is perfect for every use case, but Scala brings a lot of advantages. Let's go over some of its more desirable features and when to consider Scala.
Eugene Klimenko
March: Akka anti-patterns: overusing ActorSelection

There are a few things that you should be aware of when using this mechanism.
Manuel Bernhardt (@elmanu)
April: Towards Scala 3

Now that Scala 2.13 is only a few months away, it’s time to consider the roadmap beyond it.
Martin Odersky (@Odersky)
May: More Readable Code in Scala

A case study of code optimization for better readability and maintainability.
Mostafa Asgari (@mostafaasg)
June: Are there exceptions in Scala?

Scala developers say exceptions smell. Let's smell their libraries.
Árpád Tamási (@arpadtamasi)
July: Practical Cats: Functor and Applicative

In this post, I ’m going to introduce you some useful aspects of Cats library, mostly code snippets and I ’m not going to delve into any theory or mathematics.
Mostafa Asgari (@mostafaasg)
August: Homegrown Scala Collections - Part 2 - Unit Testing with ScalaTest

Among other things we will learn how to catch certain errors at compile time with the help or Artimas SuperSafe scalac plugin, generate HTML reports and measure code coverage with the help of the sbt-scoverage SBT plugin.
DevInsideYou (@DevInsideYou)
September: Easing Into Cats, And The Case For Category Theory Inspired Abstractions

No need to be apprehensive about adopting a library like Cats. You can start using it and start getting real-life benefits right away.
Dadepo Aderemi (@dadepo)
October: Anatomy of functional programming

The most often visited link from our newsletter last month. Basic notions of functional programming that I find myself explaining often lately into a series of articles.
Martin Menestret (@mmenestret)
November: Explore Witnesses as an Alternative to Implicits

Martin's proposition has started quite a hot discussion, becoming the most visited link at Scala Times. Time to revisit!
Martin Odersky (@Odersky)
December: Better than IO - part 1

This part covers MTL style.
Yuriy Netesov (@yuriynetesov)


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