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December 20th, 2018, ISSUE 253

READING

Scala Variables - Syntax, Declaration, Use case, Examples - Leo Benkel

After you have created your own Scala project, you can begin to write code. In this short article, we are going to learn how to use and set Scala variables.
Leo Benkel (@LeoBenkel)
Fast goto definition with low memory footprint · Metals

Metals uses a custom Scala parser to index sources at roughly 1 million lines/second in micro-benchmarks. The index is used to quickly respond to Goto Definition requests.
Ólafur Páll Geirsson (@olafurpg)
New Akka Getting Started Guide

Including the new Actor APIs.
Akka Team
Different ways to understand a monad

As soon as you start mentioning functional programming, monads pops out as something that you have to know. However, hardly anyone is good at explaining what a monad is.
Mateusz Kubuszok (@MateuszKubuszok)
MOOC: Introduction to programming with dependent types in Scala

This course is an introduction to type theory, homotopy type theory (HoTT), dependent-type programming, type-level programming, and theorem proving using Scala.
Dmytro Mitin (@DmytroMitin)
A short story about resource handling

How to design the code, so that a resource will always be properly closed, even when the programmer forgets?
Michał Matłoka (@mmatloka)
Tagless with Discipline - Testing Scala Code The Right Way

With the recent boom in the adoption of so-called final tagless encoding in Scala land, which in turn seems to be addressing the shortcomings of the Free monad approach, the testability of programs is better than ever.
Marcin Rzeźnicki
Aecor - Purely functional event sourcing in Scala, Part 2

In this post we will: peel off the layers of EventsourcedBehaviour class we’ve seen in the end of Part 1, fine tune the behavior of our Booking entity, learn a new monad transformer along the way.
Vladimir Pavkin (@vlpavkin)
Aecor - Purely functional event sourcing in Scala, Part 3

In this part we'll see how you can launch your behavior with Aecor, get a quick overview of how it works on the surface and discuss some theoretical topics, related to running eventsourced entities in a distributed system.
Vladimir Pavkin (@vlpavkin)
MOOC: Programming Reactive Systems

This course teaches how to implement reactive systems in Scala by using high-level abstractions based on event-handlers.
Roland Kuhn, Konrad Malawski, Martin Odersky, Julien Richard-Foy
ScalaX London 2018 Recap

Thanks to everyone who came down to the London BDC to take part in #ScalaX 2018! Here is a recap of some of the highlights.
Skills Matter (@skillsmatter)
Scala eXchange London 2018: A topic-based approach to conferences

Scala eXchange really had a concrete set of topics as a recurring theme throughout the whole programme. Is this a good thing or a bad thing? Read more.
Skills Matter (@skillsmatter)

PRESENTATIONS

Homegrown Scala Collections - Part 17 - Stack to Heap and Back

In this video we will learn how to move a computation from the stack to the heap in order to make it tail recursive.
DevInsideYou (@DevInsideYou)

EVENTS

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)

RELEASES

TensorFlow Scala

This library attempts to provide most of the functionality provided by the official Python API, while at the same type being strongly-typed and adding some new features.
cats-time

Cats Instances for Java Time.
Christopher Davenport

VARIA

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