I’ve done a lot of advocating of

Kotlin

and

arrow

this past months internally at ThoughtWorks, and an article of mine featuring

Either

just got published 😛 https://www.thoughtworks.com/insights/blog/either-data-type-alternative-throwing-exceptions

KVision 3.7.1 (bugfix release) is out. https://github.com/rjaros/kvision/releases/tag/3.7.1

Running into StackOverflowError but have a lot of heap space to keep the state of your computation? Kotlin Coroutines can help https://medium.com/@elizarov/deep-recursion-with-coroutines-7c53e15993e3

Continuing my intro series to coroutines - https://lankydan.dev/waiting-for-coroutines

Kotlin 4 vs. Scala 3:

This message was deleted.

my post on publishing/consuming KMP artifacts to/from maven has been published: https://medium.com/vmware-end-user-computing/publishing-kotlin-multiplatform-artifacts-to-artifactory-maven-a283ae5912d6

We are live with Kotlin London, but open to people from everywhere 🙂 https://twitter.com/KotlinLondon/status/1258081328639213568 With @danieeh now and @aballano after

I've released KVision 3.8.0 - https://github.com/rjaros/kvision. Highlights of this release: - added new

className

parameter to all DSL builder functions for better React-like HTML markup - simplified state binding functions - added root panel container types from Bootstrap 4.4 - upgraded dependencies: Coroutines 1.3.6, Spring Boot 2.2.7, Jooby 2.8.2, Bootstrap Select 1.13.17 For more details about this release see the changelog. As always any feedback is welcomed :-)

Have you ever wondered why a coroutine context is immutable and a mutex is non-reentrant? It turns out, both are corollary to the same basic rule: https://medium.com/@elizarov/phantom-of-the-coroutine-afc63b03a131

A continuation of the getting started with coroutines series i have been writing - https://lankydan.dev/cancelling-coroutines

Just had my latest piece on Kotlin’s lack of

package-private

published: https://levelup.gitconnected.com/kotlin-unit-testing-classes-without-leaking-public-api-871468695447 I’m sure you’re all aware of it, but I thought I’d share 🙂

Recently I said my goodbyes to Gson for good. Here is why I ditched beloved Gson for my Kotlin projects https://link.medium.com/QcWFLQLuy6

I just released 0.2.0 version of PunKt: live music coding library for Kotlin, now with effects support 🎶🎹🎛️ You can use it to make beats straight from Intellij, check also longer demo:

Hi there! We at mParticle  recently released a new open source product called Smartype. Built on Kotlin, it generates type-safe code for multiple platforms working off a common JSON data model. Since we help companies collect customer data from mobile, web and OTT apps, enforcement of a standardized data collection strategy is of utmost importance. Otherwise, you get all sorts of data quality issues downstream wherever customer data events and attributes are forwarded. Smartype helps developers manage data quality by enforcing a standardized data collection strategy and by collaborating with PMs and Marketers through an API that offers all CRUD operations vs. ever going to the mParticle User Interface. Next Wednesday, May 27th, at 10am PDT/1pm EDT, we'll be broadcasting live on Linkedin to discuss the challenges of managing data quality, and how developers and PM teams can leverage mParticle's new Smartype feature. Follow mParticle to get a notification when we go live. Would love for anyone to join to learn, play with it on their own time and give us feedback.

I've created a simple Graphql WhatsApp-(K)lone-Server for learning using

kotlin

,

spring-boot

,

graphql-kotlin

,

r2dbc

,

postgres

. If any one want take a look. A compatible frontend in React is available here. this is inspired by WhatsApp-Clone-Server implmented in TypeScript and Apollo Graphql Server.

Wrote a bit about representing view state as a single object. Learn how to design your state classes, and how to actually use them in practice - lots of small tips in this one! Designing and Working with Single View States on Android https://zsmb.co/designing-and-working-with-single-view-states-on-android/

Sharing a Kotlin Github template to write Gradle G Plugins here: https://github.com/cortinico/kotlin-gradle-plugin-template It’s 100% K, uses composite builds to let you use the plugin directly in the example project, has detekt/ktlint setup, and has publishing to Gradle Portal via Github Actions 🚀

@raulraja is giving a live talk on the new Type Proofs plugin for Arrow-meta now streaming on Youtube - check it out 🤗 http://www.youtube.com/watch?v=lK80dPcsNUg

FYI I have released Spring Fu 0.3.0 (with KoFu Kotlin experimental DSL for Spring Boot) and shared some insights about the roadmap https://spring.io/blog/2020/05/28/spring-fu-0-3-0-and-beyond

TechEmpower just released their latest round (19) of their server middleware benchmark. You can check the results here: https://www.techempower.com/benchmarks

#30DaysOfKotlin https://github.com/HariKulhari06/Covid-19-Tracker Create an Android application to display Covid-19 statistics of Indian and globally.

Hello! I released AutoKonfig, a Kotlin library for configuration files (and command line arguments) with many features I hope are useful and a goal to make it "just work" while being very simple to use. Zero lines of code required for setup, get values from your config file right away. https://autokonfig.nohus.dev/

Hello World! I've just written a post about MVI, State Machine and Jetpack Compose. 🔄 🎰 🤖 https://medium.com/@OscarSequeiros/mvi-state-machine-and-jetpack-compose-74bba0283f07

In our new 47 Degrees Academy launch we are gonna cover many topics including Kotlin extensively. The first talk is by @Jorge Castillo this Thursday at 18:00 CET “Async and concurrent error handling and cancellation” with #arrow Fx Coroutines https://twitter.com/47deg/status/1270379984557768705

So I wrote a library for csv-parsing in Kotlin called KSV: https://github.com/whichdigital/ksv The problem we had at 'Which?' was that we regularly import government data in ever-slightly-changing csv-format (e.g. changed order of columns, new columns at arbitrary position and column names with changing lower/uppercase and sometimes with additional spaces). So this solution looks doesn't use the index of data (because that kept changing), but uses the (normalized) column names in its mapping. A

csv2List

-function is used to map an InputStream containing csv-text into a list of a user-defined data class. Strong type guarantees, including nullability and user-defined property types are provided (as well as common csv-features like

,

being allowed in csv-values if those are surrounded by quotation marks).

@CsvRow data class DataRow(
    @CsvValue(name = "RQIA") val id: String,
    @CsvValue(name = "Number of beds") val bedCount: Int?,   // types can be nullable
    val addressLine1: String,                                // without annotation it's assumed the the column name is the the property name
    val city: String = "London",                             // without value in the csv file the Kotlin default value is used
    @CsvTimestamp(name = "latest check", format = "yyyy/MM/dd|dd/MM/yyyy")  
    val latestCheckDate: LocalDate?,                         // multiple formats can be provided separated by '|'
    @CsvGeneric(name = "offers Cola, Sprite or Fanta", converterName = "beverageBoolean")
    val refreshments: Boolean?                               // a user-defined converter can be used
)

// register a user-defined converter
registerGenericConverter("beverageBoolean") {
    it.toLowerCase()=="indeed"
}

// some text in csv-format to be mapped
val csvStream: InputStream = """
  city, addressLine1, Number of beds, latest check, RQIA, "offers Cola, Sprite or Fanta"
  if a line doesn't fit the pattern, it will be discarded <- like this line, the next line is fine because city and Number of beds are nullable
      , "2 Marylebone Rd",          ,2020/03/11,   WERS234, nope
  Berlin, "Berkaer Str 41", 1       ,28/08/2012, "NONE123", indeed
  Paris,"Rue Gauge, Maison 1", 4    ,          , "FR92834",
  Atlantis,,25000,,,
  """.trimIndent().byteInputStream()

val dataRows: List<DataRow> = csv2List(            // <- this is how you trigger the mapping, you basically tell the lib when the InputStream comes from and which type the data is
  CsvSourceConfig(
    stream = csvStream 
  )    
)

I just released Measured. A library that makes units a lot simpler and intuitive to work with. It uses the compiler to enforce correctness and lets you combine units into more complex ones using math operators. It is also extensible, making it easy to define your own units.

val velocity     = 5 * meters / seconds
val acceleration = 9 * meters / (seconds * seconds)
val time         = 1 * minutes

//  d = vt + ½at²
val distance     = velocity * time + 1.0/2 * acceleration * time * time

println(distance                ) // 16500 m
println(distance `as` kilometers) // 16.5 km
println(distance `as` miles     ) // 10.25262467191601 mi

println(5 * miles / hours `as` meters / seconds) // 2.2352 m/s

Try it out and provide feedback. (edited)