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July 6th, 2018, ISSUE 229


How to turn ugly Java APIs into elegant, type-safe Scala APIs

If you happen to use Java library with not-so-type-safe API, you should try to convert it to type-safe Scala code.
Marcin Rzeźnicki
Analyzing Pwned Passwords with Apache Spark

This tutorial will show you how to get setup for running Spark and introduce the tools and code that allow you to do data manipulation and exploration. Read on to find out how to spot the most common password lengths, suffixes, and more.
Kelley Robinson (@kelleyrobinson)
Understanding Parametricity in Scala

This concept is essential step in convincing yourself that there is something more profound to functional programming that meets the eye.
Daniel Sebban (@dsebban)
Are Scala Streams really lazy?

While Streams are a natural structure for lazy collections one must have in mind the detail on the eagerness of Cons to avoid unexpected errors.
Pedro Rijo (@pedrorijo91)
Implicits, type classes, and extension methods, part 1: with type classes in mind

Implicits. For some people, they are an indispensable feature of Scala, that allows achieving otherwise impossible things. For others a sole reason to avoid using the language.
Mateusz Kubuszok (@MateuszKubuszok)
Convolutional LSTM for ocean temperature with Deeplearning4j

We have shown how to use Eclipse DL4J to build a neural network for forecasting sea temperatures across a large geographic region.
Briton Park
Functional DevOps with Scala and Kubernetes

This story showed on a reduced example how we can use functional programming for a DevOps purpose, with all the benefits it brings.
Airframe Log: A Modern Logging Library for Scala

In Scala we can solve logging issues elegantly if we use modern logging libraries, such as airframe-log and scribe.
Taro L. Saito (@taroleo)
Functional Typelevel Programming in Scala

This is a working draft document for discussing language constructs in support of typelevel programming in Scala 3.
Martin Odersky (@Odersky)
Top link of June: The State of Developer Ecosystem Survey in 2018

Don't miss the most popular article of past month!
JetBrains (@jetbrains)


Scala - Your First Programming Language - Part 21.1 - Exceptions & Other Error Handling Techniques

In this video we will discuss all the possible ways to handle errors in Scala. It is mostly focused on exceptions, but also covers other interesting Techniques like Option, Either, Try, util.control.Exception.catch and friends, home baked types, external libraries and many other things. Most importantly it provides some guidance for when to use which technique.
DevInsideYou (@DevInsideYou)


Lambda World Seattle, September 17th - 18th

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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 10% discount for Scala Times readers!
Scala Italy (@ScalaItaly)



A type-safe, FP, Scala config library.
David Barri (@japgolly)
pulsar4s 2.0.0

pulsar4s is a concise, idiomatic, reactive, type safe Scala client for Apache Pulsar.
Stephen Samuel
Microsoft Machine Learning for Apache Spark

A Fault-Tolerant, Elastic, and RESTful Machine Learning Framework.
sbt 1.2.0 RC-1

Introduces SbtPlugin for plugin development, Cross JDK forking, Composite project, Project matrix, thin client and many other new additions.
sbt contributors

A thin client for sbt, attaching to existing process to avoid long sbt startup.
Chris Birchall (@cbirchall)


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  1. Scala Times Issue #230

    Teaching Evolution With Genetic Algorithms. Rolling Your Own Monad To Deal With Nested Monads In Scala. Case Study - Solve Crosswords Puzzle. Scala Type Level – Part 4 : Way to the HigherKinds. Implicits, type classes, and extension methods, part 2: implicit derivation.

  2. Scala Times Issue #229

    How to turn ugly Java APIs into elegant, type-safe Scala APIs. Analyzing Pwned Passwords with Apache Spark. Understanding Parametricity in Scala. Are Scala Streams really lazy?. Convolutional LSTM for ocean temperature with Deeplearning4j.

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