We use kotlin with quarkus 3 and upgraded to hibernate 6. When running tests a second time, we get an issue with postgresql enums and "org.hibernate.PropertyAccessException: Could not set value of type". Is there an easy way to determine or even render out the 'java' equivilent of the kotlin class we use? This might just look relevant different in java:

@Enumerated(EnumType._STRING_)

@Column(name = "base_currency", columnDefinition = "currency_code")

@Type(PostgreSQLEnumType::class)

var baseCurrency: CurrencyCode? = null

Hey, how could I deprecate a single function parameter? Example

fun createSimulation(
    @Deprecated("use env.enableConsoleLogger() instead")
    enableConsoleLogger: Boolean = false,
    durationUnit: DurationUnit = MINUTES
){ print() }

It seems that the @Deprecated is not applicable for parameters. Thread in Slack Conversation

I have this problem a lot. I need a class that runs some util function. My past experience basically says that objects/singletons are bad, so I should define something like

class SomeUtil {
    fun findPercentage(x: Int, y: Int, z: Int)

but something like this

object SomeUtil {
    fun findPercentage(x: Int, y: Int, z: Int)

is also convenient + less object allocation because I dont have to do SomeUtil() every time I want to use it. I suppose another potential is creating an extension function, but in this case since I have three args... I don't think that'd work? In this scenario would you do 1️⃣ Class 2️⃣ Object 3️⃣ Something else

Minimally what should I add to build.gradle.kts to use

kotlinx.coroutines.async

? I have now:

dependencies {
implementation ("org.jetbrains.kotlin:kotlin-stdlib")
implementation ("org.jetbrains.kotlin:kotlin-reflect")


implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:$coroutinesVersion")
implementation("org.jetbrains.kotlinx:kotlinx-coroutines-jdk8:$coroutinesVersion")

I'm just starting out. I'm using an open source library. Instead of constantly asking the maintainer to make updates and publish them to Maven is there a way that I can build it locally and include it in my project? Would it have to be two separate projects?

Hi, I'm learning Kotlin. I liked what I saw until I ran into pattern matching. I was disappointed to see that, AFAIK, there's no record pattern matching (destructuring) or enumeration (sealed class) pattern matching (with

when

..

is

). AFAICS, pattern match is superior in Java. Am I missing something? Are improvements on the roadmap?

I can't find the Kotlin reddit community anymore, has it been deleted?

Hello all, I am new on this workspace and also in kotlin programming language.👋

Make the Kotlin compiler crash with this one simple trick ! 😄 https://pl.kotl.in/osPNRb6eb

Where can I find documentation on Kotlin string formatting? I found a python equivalent of what I want here, but I can’t for the life of me find anything for Kotlin

This message was deleted.

The following code:

class ComposableRenderer : engine.components.ComposableRenderer {
    // ...
    override var renderComposable by setOnce<@Composable () -> Unit>()  // setOnce defines getValue and setValue
}

Results in a strange error:

Caused by: java.lang.AbstractMethodError: Receiver class engine.runtime.components.ComposableRenderer does not define or inherit an implementation of the resolved method 'abstract void setRenderComposable(kotlin.jvm.functions.Function2)' of interface engine.components.ComposableRenderer.

But shouldn't specifying it as

var

make it generate a setter?

trying to do some tutorial for ktor, but I'm getting an error on https://ktor.io/docs/creating-interactive-website.html#list_articles

Not enough information to infer type variable V

the highlight being on the 'mapOf'.

Hi all, do you know where I can add command line arguments to my kotlin native project? The

Run/Debug Configurations

only contains

Environment Variables

.

Hi, I need suggestions how to implement oauth refresh token periodically with coroutines. I want to refresh the token before the client throws unauthorized exception, i'm using ktor client in intellij plugin. I have a ktor client that is initialized with an account and credentials , upon initialization i want to start a task that will wait for expiration time - 5.minutes, refresh the token and start a new task for the next refresh. something like that: launch{ val timeLeft = computeTimeLeft(currentCredentials) - 5.minutes delay(timeLeft) retry(3.times, withDelay 30.seconds){ val newCredentials = refreshToken(currentCredentials) if(newCredentials != null){ currentCredentials = newCredentials } } onSuccess{ start a new task for the next refresh } } does it makes sense to do a while(true) loop in coroutime ? launch{ while(true){ val timeLeft = computeTimeLeft(currentCredentials) - 5.minutes delay(timeLeft) retry(3.times, withDelay 30.seconds){ val newCredentials = refreshToken(currentCredentials) if(newCredentials != null){ currentCredentials = newCredentials } } }

I think I've found a bug in Kotlin's compiler, but wanted to double-check with you. Here's a reproducible example:

class Wrapper<T>(val wrappedValue: T, parent: Wrapper<*>? = null)

fun <T : Any?, V> Wrapper<T>.wrapperOf(getter: KProperty1<T & Any, V>): Wrapper<V?> {
    return Wrapper(wrappedValue?.let { getter.get(it) }, this)
}

fun main() {
    // does not compile
    Wrapper("foo" as String?).wrapperOf(String::length)

    // but compiles with an intermediate variable
    val getter = String::length
    Wrapper("foo" as String?).wrapperOf(getter)
}

Link to the playground If I comment the eleventh line, it compiles, despite using nearly the same code just below but with an intermediate value. What do you think? Am I missing something?

Hi all, I've created a Kotlin User Group on LinkedIn for people in Norway. If you are Norway based, join the group: https://www.linkedin.com/groups/9381542/

How do I idiomatically sum the size of multiple lists that are nullable? E.g.

val totalSize = (list1?.size ?: 0) + (list2?.size ?: 0)

I'm wondering if there is a more idiomatic, easier to read syntax

I want to create a documentation site for a Kotlin library's (https://github.com/fabmax/kool) JS platform output. I'm going to be using Docusaurus (a static site generator). I want to have documentation that shows the code running (it will be code that shows WebGL graphics so its appropriate for web output). This code will have an associated code block that shows the code in Kotlin and the code in Javascript (using built Javascript library). I want to have the code implementation actually working in both Kotlin/JS and Javascript. Then I want to have that code embedded in Docusaurus. By the Kotlin/JS version and Javascript version I mean one version of the demo is written in Kotlin and compiled and the other is written in Javascript using the compiled Javascript library. It's an important distinction. My question is how to approach this: I will have to have a single platform (Javascript) Kotlin project that imports this library, and whose output is a series of demo usages of this library. Then I can either: a) have a completely separate repo that I use with docusaurus. I import the built kotlin js library manually. The advantages of this approach are that I'm keeping the Kotlin and Javascript projects separate and reducing the complexity. Incremental building is difficult because I have to build one project then build the other. However, I could just do the Javascript version of the demos first with docusaurus and then go back in later and do all the Kotlin versions of the code. b) I include the docusaurus project in the Kotlin project and create a gradle task that builds it when I like. Is this possible? Has anyone done anything like this? The advantages of this are that the build process is simplified and I have a single source of truth. In an ideal world, I could somehow include the output of the Kotlin/JS demos in docusaurus.

If I wanted to write a console app in Kotlin, is there a go-to standard CLI parser? I see a few on github, but wondered if there was one just everyone used.

if a class can become a

value class

, is there any disadvantage to doing it? assuming you already know ahead of time that you won't need additional properties.

How can I make this regex work on Kotlin/JS the same way it works on Kotlin/JVM?

fun main() {
	val r = Regex("""\h+([^:\v]+):""")
    println(r.matchEntire("   Version:")?.groupValues)
    // JVM: [   Version:, Version]
    // JS: SyntaxError: Invalid regular expression: /\h+([^:\v]+):/gu: Invalid escape
}

https://pl.kotl.in/HwXS2Fv3u EDIT: Ahh, never mind.

\h

(horizontal whitespace) doesn’t exist in JS. I’ll try replacing it with

[\t\x{00A0}\x{1680}\x{180E}\x{2000}\x{2001}\x{2002}\x{2003}\x{2004}\x{2005}\x{2006}\x{2007}\x{2008}\x{2009}\x{200A}\x{202F}\x{205F}\x{3000}]

(as found on https://regex101.com/) further suggestions are welcome!

Hello people, is there any Kotlin library for math/arithmetic/financial calculations? thinks that majority of times are done in Python. (cvxpy/osqp/scipy)

In the following code:

internal class Outer {
    class Inner
}

is the

Inner

class

public

or also

internal

?

Hi Is there any channel dedicated for android tv?

Hello all, I am trying to figure out the best way to include a data classes inherited fields in hashCode and equals methods. Code in thread

Hello everyone! I'm an intern and am just getting started with Kotlin Multiplatform Mobile. I was exploring the possibility of creating a single UI using Jetpack compose for both Android and IOS platforms. Does anyone know any resources that can get me started with this?

Hello everyone, I'm Dan. Does any one use this? https://github.com/touchlab/xcode-kotlin I have issuse with it.

I noticed "Stable time API" is listed in the *1.9.0-RC *change notes but can't find any more information about it. Does this mean the

kotlin.time

APIs are going stable in 1.9.0?

I'm not sure how boxing works sometimes with inline classes, or rather why it works that way. Here's a simple example:

@JvmInline
value class Wrapper(val value: CharSequence) : CharSequence by value

Here, since the inline class and its underlying value both implement the

CharSequence

interface, I could write either:

val wrappedValue: CharSequence = Wrapper("foo")
// OR
val wrappedValue: CharSequence = "foo"

But, in the first case, the value seems to be boxed:

@NotNull
   private static final CharSequence wrappedValue = Wrapper.box-impl(Wrapper.constructor-impl((CharSequence)"foo"));

There is probably a reason, but I don't get it. 🤔