Hi! I'm getting started with compose, and I got this error on `Window`:

Window(String = ..., IntSize = ..., IntOffset = ..., Boolean = ..., BufferedImage? = ..., MenuBar? = ..., Boolean = ..., Boolean = ..., WindowEvents = ..., (() -> Unit)? = ..., () -> Unit = ...): Unit' is only available since Kotlin 1.4.30 and cannot be used in Kotlin 1.4

This is my build.gradle.kts:

import org.jetbrains.compose.compose
import org.jetbrains.compose.desktop.application.dsl.TargetFormat

plugins {
	kotlin("jvm") version "1.4.30"
	id("org.jetbrains.compose") version "0.3.0-build153"
}

val mavenGroup = "com.theonlytails.jetpackcompose"

group = mavenGroup

repositories {
	jcenter()
	maven("<https://maven.pkg.jetbrains.space/public/p/compose/dev>")
}

dependencies {
	implementation(compose.desktop.currentOs)
}

compose.desktop {
	application {
		mainClass = "$mavenGroup.MainKt"

		nativeDistributions {
			targetFormats(TargetFormat.Dmg, TargetFormat.Msi, TargetFormat.Deb)
			packageName = mavenGroup
		}
	}
}

I have no idea what's wrong, or how to solve it. Looking at the list of dependencies, I can see kotlin 1.4.30 is there.

Are you seeing this when you do a build on the command line, or only seeing this in the IDE? Assuming you are seeing it in the IDE, it's probably because your IDE is using an old version of Kotlin, you should be able to open "Preferences" > "Languages & Frameworks" > "Kotlin", and then change the "Update Channel" to something which provides 1.4.30.

I have this:

Are you using the latest version of Intellij Idea?

Yes, with the latest EAP. I just checked for new updates.

This is what mine shows:

this is my about page:

You could try downloading the latest stable IDEA instead of the latest EAP IDEA. Not sure if that'll help you, but it's conceivable the Kotlin update was only released for the stable branch.

I'll try to downgrade to the latest stable release and see if that helps.

a few ideas:

I have also seen this error. It has been very hard for me to find a combination that actually works, between JNI core dumps, this error, and much more... I guess this is what "alpha" means. Right now the combination that has been working for me is kotlin 1.4.21 and compose 0.3.0-build141. Looks like on Mojave, you can't use a version more recent than 149 (see my posts about the jni core dumps...)

well my compose desktop app is coming up nicely with:

plugins {
    kotlin("jvm")
    id("org.jetbrains.compose") version "0.3.0-build154"
    id("com.github.johnrengelman.shadow")
}

and

    implementation(compose.desktop.currentOs)

Gradle version: 6.8.2
Kotlin version: 1.4.30
javac  version: 11.0.10 (AdoptOpenJDK 11.0.10+9)
       srcComp: 11
       tgtComp: 11
versions of core dependencies:
  kotlin-stdlib-jdk8-1.4.30
  foundation-desktop-0.3.0-build154

maybe try to "reset" your Intellij (just to be sure ...)