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June 6th, 2019, ISSUE 277

READING

Final Free Structures with Subtyping

Final algebraic form along with contravariance gives a chance to build powerful cost-free relation system between recursive types, simple or higher-kinded.
Oleg Nizhnik (@Odomontois)
Exploring the STM functionality in ZIO

How to tie ZIO STM, ZIO environment, ZIO typed errors, and ZIO execution traces into a beautiful solution that solves a real business problem quickly and correctly.
Fredrik Skogberg (@freskog)
The Evolution of a Scala Programmer

17 different ways to calculate a factorial, see how close you are to the enlightenment.
Alexey Avramenko (@vvviiimmm)
How to work with Files in Scala

This tutorial will walk through how to easily work with files in the Scala programming language, in a way that scales from interactive usage in the REPL, to your first Scala scripts, to usage in a production system or application.
Li Haoyi (@li_haoyi)
Top Link Of May: The little gems of Scala standard library

Turns out there's a huge interest in re-discovering some of these utilities.
Linas Medžiūnas

PRESENTATIONS

Cats by example - Monad Transformers

Another part of this video tutorial series.
Thomas Höfer (@TomTriple)
Monads - Part 4 - Common Monads - Maybe, List, Future, IO, Reader, State

In this video we will learn about a few common Monads. We will also learn about type lambdas, partial type application and partial unification. Additionally we will learn how to use the kind-projector Scala compiler plugin.
DevInsideYou (@DevInsideYou)

EVENTS

LX Scala & Reactive, Lisbon, Portugal, 4th - 5th July

Use promo code scalatimes_ to get a 40% discount for our readers!
LX Scala & Reactive (@lx_scala)
CFP for Lambda World, Cádiz, Spain, October 17th - 18th

Deadline for submissions is June 1st.
Lambda World (@lambda_world)
BeeScala, Ljubljana, Slovenia, November 21st - 21rd

Don't miss your ticket for this unique conference!
BeeScala (@BeeScalaConf)

RELEASES

Scala 2.13.0-RC3

Scala 2.13 is almost there! This RC introduces only some minor changes.
Scala contributors
scala-graal

Scala / GraalVM integration focused on FP & nice ergonomics from Scala, Performance & multithreading, and React SSR.
David Barri (@japgolly)

VARIA

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