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February 22nd, 2018, ISSUE 210

READING

New key for signing Scala releases

From today, 2018-02-13, we will sign Scala release artifacts with a new 4096-bit key with fingerprint 3D3A 4396 458F D629 DEAE 0F88 E9DF 618B B41F 2BCE.
Scala
3 Tips For Maintaining Your Scala Projects

Use Scala version upgrade as your learning opportunity, Manage your core libraries in a monorepo, Find your Scala Ninja.
Taro L. Saito (@taroleo)
Literal types: a case study

This article is a case study of literal types, inspired from our experience with Pine which is a functional library for HTML/XML.
Tim Nieradzik (@timnieradzik)
Comonads for scientific and statistical computing in Scala

Most categorical concepts have a dual, usually prefixed with “co”, so the dual of a monad is the comonad. Comonads turn out to be especially useful for formulating algorithms from scientific and statistical computing in an elegant way.
Darren Wilkinson (@darrenjw)
Choosing between nub and ordNub? In Scala you don't have to!

It’s probably quite rare that you specifically need nub where ordNub wouldn’t work. What I do want to highlight is that if this situation ever arose in Scala, we would be able to use implicit prioritization to avoid having to choose at all.
Ruben Pieters
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
Measuring response time in akka-http

Recently I faced a seemingly simple task of measuring how long a request takes and reporting this metric via Prometheus. After a quick google I’ve found that it’s not the first time I’ve encountered this problem.
Adam Warski (@adamwarski)
Towards A Brighter Tooling Future for Scala

People care about language tools, and it says a lot for Scala that its success has come without ever having had the best tooling. But a better development experience in other languages over the years has undoubtedly limited the adoption of Scala. Now, in 2018, there have been some developments primarily outside of the Scala community which present a new opportunity to change that.
Jon Pretty (@propensive)
Scala Center project updates 2018: mid-Jan to mid-Feb

A bunch of news regarding Scalameta, Build Server Protocol, MOOCs, Collections, Bloop, Scala Platform, Scala Compiler, Scalac profiling, scalajs-bundler, and Scalafix.
Darja Jovanovic (@darjutak)
Rocking Functional Combinators

This lesson will focus on standard Scala implementations of combinators but the ideas behind Scala combinators can be applied to combinators in any other language, be it Ruby, Java, Python, or JavaScript.
Vasily Vasinov (@vasinov)
Scala FP: how good an idea now?

Ed Kmett’s reddit comment full of biting commentary on the troubles of attempting functional programming in Scala remains the most concise listing of such problems, and remains mostly up-to-date over four years after it was written. I’d like to go through each of Kmett’s bullet points, one by one, and elaborate on what has happened in the ensuing four years since he posted this comment.
Stephen Compall (@S11001001)
Life Is A Comonad

I have recently been grappling with the concept of a Comonad, and found that there are quite a few articles that explain their theoretical footing, but not many that convey an intuitive understanding of Comonads using practical examples.
Eli Jordan
Building functional & testable HTTP APIs

In this post I have shown you how we can separate concerns of a simple web application. We achieved that using two basic tools: functions as parameters and type parameters.
Michał Płachta (@miciek)
Creating forms on your Play application

An article explaining the concepts of referential transparency, uniform access principle, and idempotence.
Pedro Rijo (@pedrorijo91)

EVENTS

flatMap(Oslo) 2018 CFP, May 3, Oslo, Norway

CFP closes on: March 1, 2018 1:03am
flatMap(Oslo) (@flatmaposlo)
ScalaUA, April 20-21, 2018, Kyiv, Ukraine

Use promo code "ScalaTimes_ScalaUA-2018-20-04" for 5% discount!
ScalaUA

RELEASES

etcd4s

Scala etcd client implementing V3 APIs
mingchuno (@MingChunOr)
mill 0.1.1

A new, promising Scala build tool. Version 0.1.1 brings tons of docs & examples.
mill contributors
Alpakka 0.17

Integrate your systems the Reactive streams way.
Alpakka contributors
twitter4s 5.5

A Twitter client for Scala. Biggest new feature: you can now attach an existing actor system to your twitter client.
twitter4s contributors
streamz 0.9

A combinator library for integrating Functional Streams for Scala (FS2), Akka Streams and Apache Camel.
streamz contributors
sbt-header 5.0.0

An sbt plugin for creating file headers, e.g. copyright headers.
sbt-header contributors
scala-xml 1.1.0

A standard Scala library for dealing with XML.
scala-xml contributors

VARIA

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