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Arrow v0.8.2 released

Arrow v0.8.2 released

It’s a new year and we’ve got a lot of things planned for Arrow’s development; we’re kicking it off with the release of Arrow v0.8.2. This release is loaded with new features, bug fixes, and vast improvements on documentation. If you’re new to Arrow, it’s an open source library that’s packed with data types and type classes that empower pure functional programming in Kotlin.

Noteworthy changes in 0.8.2 include:

  • Adds semigroup and monoid instances for Function0, Function1, and Id #1219 thanks to Jacob Bass.

  • Increases Ank’s runtime performance and memory constraints #1210 thanks to Raúl Raja.

  • Moves build, coverageReport, and deployment back to travis and adds steps for deployment #1206 / #1205 thanks to Domin Valera.

  • Adds KotlinKatas example to the related projects page #1203 thanks to Pedro Vicente Gómez Sánchez.

  • Meta Kdocs Playgrounds #1202 thanks to Raúl Raja. You can now project KDoc executable code examples from type classes into their instances automatically generating concrete runnable snippets on each of the projected extensions.

  • Completes Async by adding asyncF, cancellable, cancellableF, and shift, which also adds default implementation for continueOn #1198 thanks to Simon Vergauwen.

  • Adds Monad defer laws #1150 thanks to Jannis.

This release also includes many improvements and additions to Arrow’s docs, including the addition of a hierarchy graph for all the type class documents driven by arrow-reflect,ank:outFile new directive, and the nomnomi js library #1125.

Type class hierarchies

To view all changes and merged PRs in 0.8.2 please visit the official changelog.

We would like to give special thanks to the following contributors for this version (in no particular order):

For a full list of the contributors who have helped Arrow get to where it is today, please check out: Arrow Contributors. We’re always looking for additional help, please view the guidelines for contributing and take a look at the help-wanted issues. All levels are welcome and we offer 1:1 mentoring through Arrow’s Slack and Gitter channels.

If you would like to support Arrow, but don’t have the time to invest in contributing, consider picking up some Arrow swag! All proceeds are invested back into advancing the library.


The active development of Arrow is proudly sponsored by 47 Degrees, a Functional Programming consultancy with a focus on the Scala, Kotlin, and Swift Programming languages.

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