Why is new IDEA no longer showing gradle sourceSet dependencies on MPP projects?

What you guys think about Kotlin and its frontend "branch"? I'm already into kotlin/server, but i don't feel kotlin/js as solid in terms of: jetbrains plans, community, etc, as kotlin/server or kotlin/mobile...

Hey guys, first time posting here. What is the best channel to ask a multiplatform/cinterops question?

Kotlin 1.4.0-RC Released We’re almost there! We’re happy to unveil Kotlin 1.4.0-RC – the release candidate for the next major version of our programming language. Read on to learn about what has changed in Kotlin 1.4.0-RC, and make sure to try its new features before they are officially released with Kotlin 1.4.0. A special thanks to everyone who […]

Question: I've used Delegates.observable and Delegates.vetoable several times. Is there a way to get both (such that I get a callback before and after the value changes)? If not, what would be the recommended alternative?

Is there a way to force all Kotlin versions to 1.4 in Gradle? Even if there are libraries used, that were compiled with 1.3.72? I'm getting the following warning:

w: Runtime JAR files in the classpath should have the same version. These files were found in the classpath:
    /opt/rjaros/.gradle/caches/modules-2/files-2.1/org.jetbrains.kotlin/kotlin-stdlib/1.3.72/8032138f12c0180bc4e51fe139d4c52b46db6109/kotlin-stdlib-1.3.72.jar (version 1.3)
    /opt/rjaros/.gradle/caches/modules-2/files-2.1/org.jetbrains.kotlin/kotlin-stdlib-common/1.4.0-rc/4f17246362f6cbcf924f199a06619a4f77b51335/kotlin-stdlib-common-1.4.0-rc.jar (version 1.4)
w: Some runtime JAR files in the classpath have an incompatible version. Consider removing them from the classpath

but also compiler errors, which probably are caused by this incompatibility:

Caused by: java.lang.NoSuchMethodError: kotlin.sequences.SequencesKt.flatMapIterable(Lkotlin/sequences/Sequence;Lkotlin/jvm/functions/Function1;)Lkotlin/sequences/Sequence;
        at org.jetbrains.kotlin.resolve.calls.components.CollectionTypeVariableUsagesInfo.getDependentTypeParameters(ResolutionParts.kt:342)

This artifact https://repo1.maven.org/maven2/org/jetbrains/kotlin/kotlin-scripting-compiler-impl-embeddable/1.4.0-rc/kotlin-scripting-compiler-impl-embeddable-1.4.0-rc.pom has dependency on

kotlinx-coroutines-core

1.3.7

which makes my project classpath a mess with both 1.3 a 1.4 Kotlin versions. Is it a bug? Any way to workaround?

I'm trying to build a simple library with a github action that publishes jar files for js and jvm to a maven repository. I've so far tried jitpack and the github package repository and have had issues with both. With jitpack, it actually publishes something and I can see from the jitpack logs it generates js and jvm versions of the jar. My problem is I can't seem to figure out how to add the jvm version as a dependency. Here's an example oss project for which I tried to publish a jar: https://github.com/jillesvangurp/geogeometry. When I try to add the published jvm jar as a dependency, it instead pulls in the js version and then that doesn't work because it's not a js project. I think jitpack just randomly picks a jar that it keeps instead of publishing the -js and -jvm versions which is what I would expect. With the github package repository where I tried to do something similar, I get weird http errors. I've managed to publish a non multiplatform project to that before. I'd prefer to use that as this is a private project and I want to publish jars for internal use only.

> Task :publishJvmPublicationToGitHubPackagesRepository FAILED
FAILURE: Build failed with an exception.
16 actionable tasks: 16 executed

* What went wrong:
Execution failed for task ':publishJvmPublicationToGitHubPackagesRepository'.
> Failed to publish publication 'jvm' to repository 'GitHubPackages'
   > Could not PUT '<https://github.com/formation-res/FormationSchemaModel/formation-res/FormationSchemaModel-jvm/0.1-SNAPSHOT/maven-metadata.xml>'. Received status code 422 from server: Unprocessable Entity

I'm currently looking at the articact repository in Google cloud as another option. But before I go there, which package repositories actually work properly with the multi platform plugin? I'd be interested in people that have successfully published multiplatform library jars anywhere. This is kind of crucial to me because I want to reuse some code across web, jvm, and ultimately android & ios as well.

Hi guys, there is a line of code that I could't guess what it is, when ClassA.( ) what will happen?

typealias CompletionBlock<T> = UseCase.RequestBlock<T>.() -> Unit

RequestBlock<T> class is like this:

class RequestBlock<T> {
    private var onSuccess: ((T) -> Unit)? = null
    private var onFail: ((ErrorModel, CallableImp) -> Unit)? = null
    private var onFinally: (() -> Unit)? = null

    fun onSuccess(block: (T) -> Unit) {
      onSuccess = block
    }

    fun onFail(block: (ErrorModel, CallableImp) -> Unit) {
      onFail = block
    }

    fun onFinally(block: () -> Unit) {
      onFinally = block
    }


    operator fun invoke(result: T) {
      onSuccess?.invoke(result)
    }

    operator fun invoke(error: ErrorModel, apiCallable: CallableImp) {
      onFail?.invoke(error, apiCallable)
    }

    operator fun invoke() {
      onFinally?.invoke()
    }
  }

Hey Kotlin team - I want to clarify Kotlin logo colouring guidelines (current guidelines are only referring to “Kotlin” text colour

Do not display the word Kotlin using any different stylization, color, or font from the surrounding text

) What are your thoughts on using black Kotlin logo?

Does Kotlin have a nice way to "chain" two sequences? That is, return a sequence that first goes through the elements of the first sequence, then of the second. The closest thing I see is flatten, which I could make work, but it's intended for sequences of sequences, not simply 2 (or 3, etc) sequences that I already have as separate variables

I just created a project using gradle + Kotlin JS and I want to use File class from Kotlin Jvm

In Kotlin, there's a bit of an issue where even if you have something like this:

data class Foo(val bar: List<T>)

Despite the use of both val and List (as opposed to MutableList), it's still pretty easy to mutate data out from underneath Foo. I was curious how many people had felt the need to have some kind of true immutable list type, to prevent this scenario? One pleasant surprise in Kotlin was that I was able to implement something reasonable in just a handful of lines. Even just:

class ImmutableList<T> private constructor(val data: List<T>) : List<T> by data {
    constructor(x: Sequence<T>) : this(x.toList())
    constructor(x: Iterable<T>) : this(x.toList())
}

operator fun<T> ImmutableList<T>.plus(x: Sequence<T>) = (data.asSequence() + x).toImmutableList()
operator fun<T> ImmutableList<T>.plus(x: Iterable<T>) = (data + x).toImmutableList()
operator fun<T> ImmutableList<T>.plus(x: T) = plus(sequenceOf(x))

fun <T> immutableListOf(vararg elements: T) = elements.asIterable().toImmutableList()
fun <T> Sequence<T>.toImmutableList() = ImmutableList<T>(this)
fun <T> Iterable<T>.toImmutableList() = ImmutableList<T>(this)

Is already pretty usable (thanks mostly to delegation). And now we can go back to our previous example:

data class Foo(val bar: ImmutableList<T>)

This is actually conditionally immutable depending on the T (say it's an Integer or String). I'm curious if many people are using things similar to this? Or are people just living with the possibility of unexpected mutations in Foo, finding it not too big of a problem?

Suppose I want, in a certain scope, to use my own map function instead of the standard library one. How do I do that?

Is it possible to play with coroutines on https://play.kotlinlang.org?

What differences are there between Kotlin SDK and JDK?

Hey guys, does anyone have a hint what I did wrong here?

var email: String? = "default"
        set(value) {
            field = setEmail(value)
        }

    fun setEmail(value: String?): String? {
        val emailRegex = Regex("^\\w+([-+.']\\w+)*@\\w+([-.]\\w+)*\\.\\w+([-.]\\w+)*\$")
        val isValidEmail = value != null && emailRegex.matches(value)
        return if (isValidEmail) value else null
    }

The shown field is part of a representation of an old legacy db, which might has a "wrong" email adress in it. Its set by jpa, but I would like to perform the shown operation when the field is set to filter out "wrong" emails. The function is tested and is returning the correct result. However, email is always set as "default". What did I do wrong here? Thanks ahead!

Hi! How do I link to an external URL in the `@see`tag in documentation?

I'm trying out 1.4-RC and I'm having a problem with intellisense on build.gradle.kts files They compile and reload fine, but the IDE doesn't pick up the JDK and I get red highlights on everything such as java.lang.Object

How do I use delegation on a member that I don't want to declare in the primary constructor?

Am I missing an obvious reason why there's a mapNotNull but no associateNotNull?

I've created a project with a relatively simple

build.gradle.kts

file: https://gist.github.com/sanity/b89e7d1be5cfd6779e0186f929b45333 But for some reason a number of JVM packages aren't on my classpath, particularly anything in the 

java.util.concurrent

 package, am I missing something from my build file?

I’ve been trying to figure out how to specify the signature of a generic function when it’s used as an argument to a higher order function. I’m looking at a function that tries to compare some arguments of unknown type.If they can be cast to numbers, it compares them as numbers.  If they are strings, it compares them as stings. It’s possible to write one of these for each compare, of course, but the casting logic is duplicated. It would be nice to factor that out using a higher order function:

compareOp(v1: Any, v2: Any, f: (Any, Any) -> Boolean): Boolean
...
compareOp(v1, v2, {x, y -> x < y})

This isn’t quite right though. The “<” on the last line doesn’t compile. Any < Any doesn’t exist. Since I’m only trying to compare as strings or numbers, it’s possible to write this as:

compareOp(v1: Any, v2: Any, fs: (String, String) -> Boolean, fd: (Double, Double) -> Boolean): Boolean
...
compareOp(v1, v2, {x, y -> x < y}, {x, y -> x < y})

That works, but still doesn’t feel right. {x, y -> x < y} is duplicated. I should be able to pass it in just once. Its signature is:  <T> fun comparison(x: Comparable<T>, y: T): Boolean As far as I can tell, it’s not possible to stick this type parameter in the signature of compareOp. I tried making an interface Comparison<T> with an “operator fun invoke” that has the Comparable<T> signature. That still doesn’t quite work. compareOp has to specify a single explicit value for T. Has anyone solved this sort of issue?

What's the new dependency for kotlinx serialization for RC1? I see that coroutines has changed from kotlinx-coroutines-core-common and specific platforms to just kotlinx-coroutines-core, but implementation("org.jetbrains.kotlinx:kotlinx-serialization-runtime:1.0-M1-1.4.0-rc") doesn't seem to work...

The only way I can think of is to have a private class Key at file scope, and then the class in question can members that accept a Key. Seems a bit hacky though.

Does anyone have any good tips to get the very best performance out of IntelliJ? I have a Desktop with 32 cores and 64 GB RAM and would love to just give IntelliJ the right configuration so it would be incredibly fast. 😛

Has anyone else seen constant "updating indices"/`Analyzing...` in files since updating to intelllij 2020.2? I've restarted intellij but it's still going. All day.

What's the best way to instantiate a constant ULong/UInt value that's out of Long/Int range?

String.toULong

?

Did kotlin serialization runtime get pulled from bintray? Yesterday org.jetbrains.kotlinx:kotlinx-serialization-runtime-js:1.0-M1-1.4.0-rc worked and today it doesn't... https://dl.bintray.com/kotlin/kotlin-eap/org/jetbrains/kotlinx/