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July 12th, 2018, ISSUE 230

READING

Teaching Evolution With Genetic Algorithms

An example program used to teach the basics of evolution to a 8 year old.
Jeffrey Massung (@codeninja_blog)
Rolling Your Own Monad To Deal With Nested Monads In Scala

If you don't want to involve libraries like Cats, see how to build a homegrown alternative to having to use Monad Transformers.
Dadepo Aderemi (@dadepo)
Case Study - Solve Crosswords Puzzle

This time I searched in functional programming category and crosswords-101 caught my eye and I decided to solve it in Scala in a very clean and understandable way and not in a contest style way of programming!
Mostafa Asgari (@mostafaasg)
Scala Type Level – Part 4 : Way to the HigherKinds

In this blog we will talk about the HigherKinds or we can say that import scala.language.higherKinds.
Implicits, type classes, and extension methods, part 2: implicit derivation

While this may not be enough for you to cover all use cases, it should be enough to let you understand where derivation is used and whether you could use it for handling your use case.
Mateusz Kubuszok (@MateuszKubuszok)
Inference Driven Design

In this post, we’ll look at a library design issue faced in FS2 and how constraints like Scala’s type inference algorithm, minimization of explicit type annotations, and invariance under refactoring can be balanced.
Michael Pilquist (@mpilquist)
Supervision & error handling in ZIO, Akka and Monix (part 3) + series summary

In this last part we’ll look at the final feature that makes actors stand out: error handling, supervision and the actor hierarchy. There's also a full summary of all the compared features in a table.
Adam Warski (@adamwarski)

PRESENTATIONS

Scala - Your First Programming Language - Part 22 - Packages, Namespaces & Imports

In this video we will talk about packages - a mechanism for splitting your code into modules which may reside in separate files while maintaining the precious cohesion.
DevInsideYou (@DevInsideYou)
Scala Days North America 2018 presentations

All the recordings are now available!
Scala Days
Thinking Less with Scala - Video from Scalapeño 2018

The talk demonstrates that good Functions Signatures, Data and Functional Patterns keep your mental stack small.
Daniel Sebban (@dsebban)

EVENTS

Lambda World Seattle, September 17th - 18th

Use promo code STLW18 for Scala Times readers to get 10% discount!
47 degrees (@47deg)
Lambda World Cádiz, Spain, October 25th - 26th, 2018

Use promo code STLW18 for Scala Times readers to get 10% discount!
47 degrees (@47deg)
Scala Wave, September 6th - 8th, 2018, Gdańsk, Poland

Use code scalatimes_10, registration with special 10% off discount, to use on the conference day, ends on June 30th!
Scalac (@scalawavepl)
Scala Italy, September 14th-15th, Florence

Use promo code SCALATIMES_U2N for a 20% discount for Scala Times readers!
Scala Italy (@ScalaItaly)

RELEASES

scala-http-api

Project showing up how you could implement a HTTP API with Scala.
scala-http-api contributors
scalaz-deriving

scalaz-deriving makes it easy to derive typeclass instances for your data types.
Sam Halliday (@fommil)
stringmask 1.3.0

Mask your case class fields in toString output by compile-time annotations. Now with support for package protected classes.
Krzysztof Ciesielski (@kpciesielski)
udash-core 0.7.0

Udash is a Scala.js framework for building beautiful and maintainable web applications. Version 0.7.0 brings numerous performance improvements in properties and fixes.
udash contributors
Dotty 0.9.0-RC1

Improved REPL, Drop requirement that implicit functions must be non-empty, Emit feature warnings for implicit conversions, Support for compiler plugins and more!
Dotty contributors

VARIA

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