In a Kotlin multiplatform library, when generating test classes they become

internal class FooTest

. Why

internal

? Are they otherwise published or too accessible somehow?

I'm trying to modify the

IntRange

using

onEach

function like this

val range = (1..3).onEach { it + 1}
println(range) // expecting 2..4 but still getting 1..3

So what should I try?

I am a pretty new Kotlin dev, but I have done 20+ years as a C# dev. In C# I have used a plugin called AutoMapper in some projects for mapping a domain model to an application model. What is the preferred way to do this in a big and complex Kotlin Android project? Is there a plugin that does this well or do you recommend some other approach?

is there a way to access attributes of an object dynamically for example

class Bar {
   baz: String
   zab: String
}

class Foo {
    attributes: Bar()
}

var foo = Foo()

for(attr in foo.atributes) {
    println("$attr") 
    // baz
    // zab
}

I’m looking at using kotlin-reflection lib and when i use

this.condiments::class.members

, i can see the attributes with a bunch of metadata, but i cant get the value.

var foo = Foo()

for(attr in foo.atributes::class.members) {
    println("$attr") 
    // baz
    // zab
}

I have a list

[A, B, B, B, A, B, B]

(

A

and

B

are instances of sealed classes). I want to transform it to

[[A], [B, B, B], [A], [B, B]]

(so, a list of lists, grouped by classes). How?

Does anyone know the health of the Valiktor project? The last commit was October of last year, and there are several pending issues and PRs. Otherwise, any recommendations for Kotlin-first validation libraries? 😄

Has anyone used Bazel with IntelliJ and Kotlin? How is the experience of working with kotlin+bazel in general?

I've got a sealed interface

NbtTag

that's implemented by

NbtInt

,

NbtString

,

NbtList<T : NbtTag>

, etc. (for a kotlinx.serialization format library) NbtList can only contain one type of tag (so

T

can't be

NbtTag

), and I'm wondering if there's a better way to restrict that. Here's basically what I'm doing right now (which seems overly verbose):

class NbtList<out T : NbtTag> internal constructor(
    val content: List<T>
) : NbtTag, List<T> by content

// Pseudo constructors to limit T to concrete types
fun NbtList(content: List<NbtInt>): NbtList<NbtInt> = NbtList<NbtInt>(content)
fun NbtList(content: List<NbtString>): NbtList<NbtString> = NbtList<NbtString>(content)
fun NbtList(content: List<NbtList<*>>): NbtList<NbtList<*>> = NbtList<NbtList<*>>(content)
// plus 9 more for the remaining tag types...

Are there any other ways I can accomplish this and limit the constructor/content?

Hi, Is there a way to know the instance class of a class property dynamically? For example I have a

data class MyClass(val person: Person)

. When MyClass is instantiated, it's built with a PersonImpl as the Person is the interface.

val result = MyClass(PersonImpl())

I need to dynamically know that the person attribute is a PersonImpl. I have been trying with `result::class.declaredMemberProperties`but I can't get the PersonImpl from it. Thanks

I have a

List

of objects that each contain an

Int

property. What's the most idiomatic way of getting the sum of those `Int`s? Edit: I think I found it:

sumOf

❤️

Don’t Kotlin or IDEA provide nullability annotations for

java.time

classes or do I have to configure anything for that?

Hi everyone! 👋 🎉 The first announcement in our renovated channel is about the moderators of this space. At the moment we have 13 confirmed moderators, and they will be responsible for observing a total of 53 channels. For all other channels, if any issues arise, members can ping any of the moderators or admins directly, or they can post a message in #meta All moderators will have [Mod]/[MOD] next to their names. Now without further ado, here they are :virtual-meeting:: 1. @andylamax – #coroutines, #kotlin-native, #webassembly, #serialization, #random, #javascript, #react 2. @gildor – #coroutines, #android, #gradle, #multiplatform, #getting-started, #kotlin-asia, #singapore 3. @Eric Ampire [MOD] – #events 4. @louiscad – #coroutines, #android 5. @Zach Klippenstein (he/him) [MOD] – #coroutines, #compose, #compose-desktop, #compose-web, #squarelibraries, #library-development 6. @gammax – #feed, #detekt, #appintro, #chucker, #fosdem, #london, #berlin, #hamburg, #sweden, #ktlint, #kug-leads, #kotlinconf, #koin, #koin-dev, #spek, #vkug 7. @simon.vergauwen – #arrow, #arrow-contributors, #arrow-meta 8. @Holger Steinhauer [Mod] – #fosdem, #berlin, #vkug, #german-lang, #server 9. @Imran/Malic – #munich, #arrow 10. @raulraja - #arrow, #arrow-contributors, #arrow-meta 11. @Youssef Shoaib [MOD] – #getting-started, #feed, #language-evolution, #language-proposals 12. @altavir – #mathematics, #science, #datascience, #education 13. @sam – #kotest, #kotest-contributors ℹ️ You can read more about our changes to the community and the responsibilities of moderators in this change proposal. If you would like to apply to be a moderator, please ping me @Alina Dolgikh [JB]. BTW threads for the discussion of announcements are now allowed in this channel.

🆕 :kotlinnew: Hi everyone! Kotlin 1.5.30 has been released. It includes: • Sealed 

when

 statements • Support for

suspend

functions as supertypes • JS IR compiler in Beta • Native support for Apple silicon • And more Learn more in the blog post.

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⚠️ Vulnerability alert. Please pay attention if you are using karma with your Kotlin/JS projects https://kotlinlang.slack.com/archives/C0BJ0GTE2/p1634926443022700

IMPORTANT. PLEASE READ: ua-parser-js exploit and Kotlin/JS. https://blog.jetbrains.com/kotlin/2021/10/important-ua-parser-js-exploit-and-kotlin-js/

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:compose-multiplatform: 🆕 The declarative UI framework for Kotlin – Compose Multiplatform – has reached Beta 🎉 This framework makes it possible to build Android, Desktop, and Web UIs with the same APIs and concepts. ℹ️ Check out this blog post for more details about what the Beta release brings to Compose Multiplatform. To participate in discussions about the framework, join the #compose, #compose-web, #compose-desktop, #compose-ui, and #compose-wear channels.

The final preview of Kotlin 1.6.0 is out. We’ve been polishing many great features for the upcoming 1.6.0 release, and now we want to make sure they are ready to go. Try it and share your feedback with us: https://github.com/JetBrains/kotlin/releases/tag/v1.6.0-RC2

📣 🚀 🎉 Kotlin 1.6.0 has been released with: :kotlinnew: Language features: • Sealed (exhaustive) when statements • Suspending functions as supertypes • Improved type inference for recursive generic types, and more ⛺  Kover, a new code coverage Gradle plugin 🧠  An experimental new memory manager for Kotlin/Native Please read the blog post to learn what else is new in Kotlin 1.6.0.

🎨 :compose-multiplatform: 🆕 Compose Multiplatform by JetBrains, a declarative UI framework for Kotlin, has reached version 1.0, which makes it ready for production use! 👉 Read the blog post to get all the details 😒lack: To participate in discussions about the framework and share your feedback, join the #compose, #compose-web, #compose-desktop, #compose-ui, and #compose-wear channels.

👩‍💻👨‍💻👩‍💻 It’s that time of the year – Advent of Code! If you are participating in AoC 2021, check out the videos prepared by our amazing dev advocates. Sebastian shares  on solving AoC 2021 in Kotlin, while Anton demonstrates how he . You can also take part in the Kotlin giveaway by sharing your code on GitHub 🎁. More details are in this blog post.

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The release candidate for Kotlin 1.6.20 is out: https://github.com/JetBrains/kotlin/releases/tag/v1.6.20-RC Learn about the main features and improvements in Kotlin 1.6.20, including a prototype of context receivers for Kotlin/JVM and support for parallel compilation of a single module in the JVM backend: https://blog.jetbrains.com/kotlin/2022/02/kotlin-1-6-20-m1-released/

Kotlin 1.6.20 has been released. Highlights include: • Prototype of context receivers on JVM • Definitely non-nullable types • Performance improvements for JVM, Native, and JS • Hierarchical structure support for multiplatform projects Read more in the blog post.