Functional Roundup for July 1, 2016

• by Maureen Elsberry
• •
• July 01, 2016
• •
• news• scala• akka• typelevel• functional roundup
• |
• 4 minutes to read.

Scala 2.12.0-M5 released

Scala 2.12.0-M5 was released on June 29th.

2.12.0-M5 featured the merge of 96 pull requests and resolved 49 JIRA tickets.

Adriaan Moors lists the following as highlights:

• 5251 concrete trait methods are compiled to a static method (in the interface classfile) containing the actual implementation, and a default method forwards that to the static one.
• 5085 classes extending traits no longer get mixin forwarders (in most cases), the JVM picks the correct default method.
• 5102 adds partial unification of type constructors (behind -Ypartial-unification) and fixes SI-2712. Thanks @milessabin! The optimizer now listens to -opt (instead of -Yopt)
• SI-9390local methods that don’t capture this are emitted as static to prevent capturing the outer instance in lambdas.

2.12.0-M5 is not binary compatible with any other Scala release and requires a Java 8 runtime.

You can view more of the release notes here: Scala 2.12.0-M5.

Scalafmt 0.2.9 released

Hot off the trails of 0.2.6 and 0.2.9, Scalafmt 0.2.9 was released this week.

0.2.9 includes two new flags, a few bug fixes, and a WIP IntelliJ inspired style according to Ólafur Páll Geirsson:

• Decrease non-idempotent cases in test suite from 15 to 11.
• New flag: --reformatDocstrings false: disable docstring reformatting
• New flag: --bestEffortInDeeplyNestedCode: reenable best-effort formatting as was default prior to 0.2.6.
• Improvements to --danglingParentheses
• Bug fix in try/catch without curly braces [350](https://github.com/olafurpg/scalafmt/issues/350
• Bug fix in function applications with lambda arguments.
• Improved multiline strings in function calls with many arguments.

More details regarding this update can be found here: Scalafmt changelog.

Monix 2.0-RC8 released

Alexandru Nedelcu announced the release of Monix 2.0-RC8. The update now features a composable Consumer type.

The release has the following critical bug fix:

• #181 the default operators on CancelableFuture are triggering StackOverflow exceptions

And ten new features including:

• 184 introducing the Consumer type, a factory of subscribers that makes it easier to specify reusable and composable consumers and for example, it makes it possible, out of the box, to load-balance the workload between multiple subscribers in parallel; see the description.
• 180 the Observer.feed function now has an overload that does not take a cancelable, because it’s awkward coming up with one if it isn’t needed; there’s also a onNextAll extension for both Observer and Subscriber which can push a whole collection of events.
• 187 integrates the MonadCombine type-class from Cats, being similar to the Scalaz MonadPlus, as somehow this was missed in the initial integration.
• 191 introduces by default an implicit conversion from Any to Coeval.Now, to make it easier to use Coeval as function parameters - the default will thus simply be strict evaluation, strictness being usually the default in Scala

You can view the full list of improvements on 2.0-RC8 here: Monix: Version 2.0-RC8 Released

Apache Spark 1.6.2 released

The latest maintenance release of Apache Spark contained stability fixes including a wealth of bug fixes, improvements, and a few new features.

• 8428 TimSort Comparison method violates its general contract with CLUSTER BY
• 11327 spark-dispatcher doesn’t pass along some spark properties
• 14327 Tasks that fail due to CommitDeniedException (a side-effect of speculation) can cause job failure
• 14468 Always enable OutputCommitCoordinator

You can view the full list of bug fixes and changes here: Spark 1.6.2 release notes

Suggested information to digest this weekend:

The functional programming community has no shortage of excellent conferences and talks. Here are just a few that were recently released that we recommend checking out if you missed them the first time:

Raúl Raja:

• Intro to FP & Typeclasses
• Software Craftsmanship Conference - Pamplona, Spain

Raúl Raja presents a brief introduction to the core Functional Programming traits and the power of coding to abstractions using Typeclasses.

View the slides here:

Spark Summit Presentations:

• All presentations
• Spark Summit 2016 - San Francisco, CA

The video presentations from Spark Summit this June are now available from the Apache Spark YouTube channel.

Find the videos here: Spark Summit 2016

Upcoming Events:

Scala at the Sea

• July 12th
• WhitePages - Seattle, WA

Scala Up North

• August 5th - 6th
• Concordia University - Montreal, Quebec

Scala World

• September 10-14th
• The Rheged Centre - Cumbria, UK

Have a news tip for us? Tweet to us @47deg or send to us via email here.