Given recent panic with jcenter shutdown, I've started thinking that it'd be nice if jetbrains could come to some sort of partnership with google and endorse google package registry as official kotlin registry. Given that main use case for kotlin is still android development i think it would make a lot of sesnse for both companies. Furthermore, I'm not sure that tying kotlin to "legacy" technology such as maven is the most future-proof way to go. I'd like to hear what JB and the community thinks about the idea.

Hello. What's the right channel to ask about Kotlin scripts. main.kts extension to be more specific

What do I have to do to make integration tests run? I have followed https://docs.gradle.org/current/userguide/java_testing.html#sec:configuring_java_integration_tests but I think it may have to do with me using Kotest. The tests run just fine in Intellij but not using gradle.

So sealed interfaces are coming (https://blog.jetbrains.com/kotlin/2021/02/new-language-features-preview-in-kotlin-1-4-30/#sealed-interfaces) with

Kotlin 1.5 removes both constraints: you can now make an interface sealed. The subclasses (both to sealed classes and sealed interfaces) should be located in the same compilation unit and in the same package as the super class, but they can now be located in different files.

Now my question is, can you still extend a sealed interface in a TestCase (within the same module)? Do the tests within a Gradle

test

-folder belong to the same sourceSet (and therefore compilation unit?) as the sources under

src

?

How do I specify

kotlinOptions

in gradle for sourcesets other than

main

and

test

? I have problems setting the `languageVersion`/`apiVersion` for my

testFixtures

sourceset

Hey, I'm trying to use a @Serializable annotation on a data class for decoding JSON from a string, but it looks like the annotation isn't being applied because it gives this error:

kotlinx.serialization compiler plugin is not applied to the module, so this annotation would not be processed. Make sure that you've setup your buildscript correctly and re-import project.

When I add "org.jetbrains.kotlin.plugin.serialization" to the plugins though, it gives me different errors which I don't really understand:

java.lang.IllegalStateException: Backend Internal error: Exception during code generation

. For reference, this is in a Jetpack Compose Desktop app, if that has anything to do with the issue. Anyone know the problem?

I found certain cases where when using method reference, IDE screetches to a halt If I change it to a lambda, then it works fine where should I report this?

Question regarding withContext; perhaps we're using it incorrectly We are injected some thread context into the call and running a block of code with that injected thread context, so something like

withContext(InjectThreadContext(...)) {
    //doStuff
    //otherStuff
    //moreStuff
}

So this works in the sense that when the coroutine resumes/starts it'll inject our thread context and right after it suspends we have it restore the original context by closing our injected context. But once we reach the end there is no suspend again so the injected context then leaks out of the block whereas we want it to do like a final close. Is there a different method we should be using?

Hey 👋 Anyone having issues using

when

expressions? I keep getting a warning telling me it should be exhaustive but I have every possible branch filled in? I am only seeing this after updating the Kotlin plugin in Android Studio to 1.4.30

what is kotlin equivalent of Java's

charAt

?

I must admit my mind was blown 🤯 Who can explain to me what’s exactly is going on here?

Are the 1.4.30 / 1.5 inline (value) classes backed by Valhalla or is it compiler shenanigans under the hood?

update: this is my code:

build.gradle

application {
    // Define the main class for the application.
    mainClass = 'translator.AppKt'
}

task myExecTask(type: JavaExec) {
    classpath = sourceSets.main.runtimeClasspath
    main = 'translator.AppKt'
    args project.getProperty('myFirstArgument') + ' ' + project.getProperty('mySecondArgument');
}

gradle myExecTask -PmyFirstArgument=foo -PmySecondArgument=bar

got error:

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: Index 1 out of bounds for length 1

--------------------------------------------------------------- how do I pass multiple arguments to gradle? this doesn't work

gradle run myfirstargument mysecondargument

Hello

Koliners

I want ask about

SecurityByDesign

if there better setup how to create the classes https://gist.github.com/marzelwidmer/6aa9733c919f2a8dc6aa84116fe4a580 what I don’t like is…

invoke

function is available

data class Customer (val firstName: FirstName, val lastName: LastName, val gender: Gender)
// Domain Primitive
data class FirstName private constructor(val value: String) {
    companion object {
        // Create Object
        operator fun invoke(value: String) = FirstName(validate(value = value))
        private fun validate(value: String): String {
            check(value.isNotEmpty()) { "value must be non-empty" }
            check(value.trim().length >= 2) { "wrong value length" }
            check(value.trim().length <= 20) { "wrong value length" }
            return value
        }
    }
}

Suppose you did a lot of "here's a ubytearray, i need to pad it up to certain length with a value", what (if any) extension would you add? I'm not a fan of methods that take two integers, because you lose some safety due to the fact that it's easy to misguess the order of the parameters.

what is Kotlin equivalent of this Java's code:

str.charAt(str.length() -1) == ' '

I do not understand why casting

this

to

S

is unchecked. Is it a bug or I miss something

Hello everyone, i wanted just to know, Is there any way i can use kotlin multiplatform mobile on windows??

How can I use

Result<T>

from Java code? My interface returns

Result<T>

. i am seeing

Object

instead of

Result<T>

😕

This message was deleted.

Hi all...Just started getting this message in IDEA community after upgrading to kotlin 1.4.30

'@JvmOverloads' annotation cannot be used on constructors hidden by inline class rules

The class in question seems straightforward

class AudioClassifyWorkflowParameters @JvmOverloads constructor(...

I'm not clear how to interpret the error, as I don't know what "hidden by inline class rules" is referring to. Any insight appreciated.

Let's say I wanted to add a little endian encoding API to unsigned integers (UByte, UShort, UInt, ULong) that looked something like:

anInt.le.ubytes

. In Swift, I'd accomplish this with something like: protocol LittleEndianEncodable { var byteSize:UInt get() var le:LittleEndianEncoder get() } extension LittleEndianEncodable { var le:LittleEndianEncoder<Self> { return LittleEndianEncoder(self) } } struct LittleEndianEncoder { var value:LittleEndianEncodable var ubytes:Data { // well, Data in Swift return 0..<self.value.byteSize.map { index in self.value >> (index * 8 ) & 0xFF } } } Or something close to that. Then I'd just add an extension to the existing int classes and be off to the races. But in Kotlin, I can't create a new interface that I then enforce on existing class types. Is there an alternate approach to do this? Basically I want

le

to return a "trampoline" object which can return the

ubytes

for the object it's wrapped, and do it generically, so I don't have to make individual transformer types for each uint type. I looked through the docs, hoping to find that there was already something that answers the byte size for int types, but didn't see anything 😞

Why is this forbidden?

I have a question about "exhaustive when expression": if I have an enum value which is guaranteed not to have a specific value, the compiler still insists on a branch for that value. Is there a way to avoid that? Concrete simplified example (which does not compile unless I uncomment the one commented out line):

import kotlin.random.Random

enum class Priority { LOW, MEDIUM, HIGH }

fun main() {
    val priority = Priority.values()[Random.nextInt(Priority.values().size)]

    val s1 = when (priority) {
        Priority.LOW -> 1
        Priority.MEDIUM -> 2
        Priority.HIGH -> 3
    }

    val s2: Int
    if (priority == Priority.LOW) {
        s2 = 1
    } else {
        s2 = when(priority) {
//            Priority.LOW -> throw IllegalStateException()
            Priority.MEDIUM -> 2
            Priority.HIGH -> 3
        }
    }

    println("s1=$s1 s2=$s2")
}

Is there any differences between kapt, ir plugin, and ksp (kotlin symbol processing)? 🤔

Hi everyone! I'm new here and I've just started to work with Kotlin and Arrow Meta. Is there a way to see the compiler plugin's stdout in the console when compiling it with gradle?

println

doesn't seem to show up...

Hi all! I'm new here and I'm assessing the capabilities of Kotlin when working in the Big Data and Data Science fields. Any suggestions? Thanks!

Is it only possible to send on a channel from a coroutine? What if I have regular code that produces something that I want to send to a work pool for example how do I do that?

I want to make an application using kotlin as a backend. Please help