is there a channel where to ask help about writing a kotlin compiler plugin?

I'm trying to do something like this:

val list = listOf(1,2,3,4,5)
when (list) {
    all { it < 10 } -> foo()
    any { it % 2 == 0 } -> bar()
    else -> baz()
}

but it doesn't seem to be possible and I'm not sure why.

Is there any other way to use property as delegate for another property?

class Container {
    val view: View2 = View2()
    var onClickListener:(() -> Unit)? by view.onClickListener // does not work
}

class View2 {
    var onClickListener:(() -> Unit)? = null
}

This message was deleted.

Will @JvmInline on value classes only be present for single field classes? Will value classes with multiple fields compiled for Valhalla JVMs lack this annotation? Can we be sure that value classes annotated with @JvmInline will always have exactly one field even in future Kotlin versions?

Any ideas how can I parse this time with a format like this: 2017-07-24 034526 +0000 UTC” I tried this but failed with “DateTimeParseException”

import java.time.Instant

import java.time.ZonedDateTime

fun main() {

val time = "2017-07-24 03:45:26 +0000 UTC"

val parsed1: ZonedDateTime = ZonedDateTime.parse(time) // fails

val parsed2: Instant = Instant.parse(time) // fails

}

}

Hi, do you know any good library for doing simple but performant 3D graphics ? With a friend we want to try making a little Minecraft renderer to visualize our world, but I don't know what to use, he is on Linux and me on Windows so we need something multiplatform, and I guess that doing this with Compose will be great if we want to keep it simple and quick to develop ?

Hi all, does anybody know if there’s a pure Kotlin implementation of Jwt? One that doesn’t use java.security, nor javax.crypto, etc.?

any one faced EditText doesn't appear in preview window in android studio? note : when i set background it's work fine ? but i need it without background ! i have search and try many solutions but still ?

when using contracts, is there anything to guarantee that

block

isn’t called 0 or 2+ times?

contract {
        callsInPlace(block, InvocationKind.EXACTLY_ONCE)
    }

Hello All! I seem to have an issue while working with nested coroutines with single threaded dispatcher. When I call scope.launch() inside another scope.launch(), the inner block wont get executed if I use single threaded dispatcher. Here is an example

val dispatcher = ScheduledThreadPoolExecutor(1).asCoroutineDispatcher()

val customScope = CoroutineScope(SupervisorJob() + dispatcher)

customScope.launch{
	//This block works fine.
	customScope.launch{
		//This block is not executing
	}
}

  However it woks fine If I change the dispatcher in the inner block. But In my case, I need to have the same dispatcher in both launches. Any help would be very much appreciated.

In the specific context of Compose, but a general higher level question on nested lambdas. Do you usually ignore this implicit shadowing warning, or do you do something like

{ change -> change.consumeDownChange() }

for the inner block?

since something like this doesn’t work in kotlin

var a = true
var b = false
when (a, b) {
   true, true -> ...
   true, false -> ...
   false, true -> ...
   false, false -> ...
}

is this the best alternative?

when {
   a, !b -> ...
}

since mapOf() on the jvm internally uses a LinkedHashMap which seems to keep order: so, does kotlin-mapOf() officially guarantee that the order of adding entries is preserved?

Image from iOS.jpg

Are there any bug fix releases planned for Kotlin 1.5.10? It seems like there were memory leaks introduced with Kotlin 1.5.0 and 1.5.10 didn't resolve all of them. From what I last saw on YouTrack, they are scheduled to be fixed in 1.5.30, but wouldn't things like that be a candidate for a bug fix release?

is there a way to debug why the kotlin daemon isn't working? we are getting:

Could not perform incremental compilation: Could not connect to Kotlin compile daemon
Could not connect to kotlin daemon. Using fallback strategy.

since we upgraded from 1.4.31 to 1.5.10 but i'm not sure what to file in a bug or anything

In what cases will use of a Sequence be significantly slower than use of an Iterable with Sequence's current implementation that they cannot be iterated over multiple times?

Hi. I’m making new class for variable type which has string value like below.

class CustomFieldTypeA() {
    var value: String = ""
    private val charset: Charset = ACharset()
}
class CustomFieldTypeB() {
    var value: String = ""
    private val charset: Charset = BCharset()
}

data class TestData(
    var field1: CustomFieldTypeA = null,
    var field2: CustomFieldTypeB = null,
)

The reason to use CustomFieldType is to have charset for string. And I want to use this type in the same way to use String like below

// for setter
val obj = TestData()
obj.field1 = "hi type 1"
obj.field2 = "hi type 2"
// for getter
val str = obj.field1
print(str) // hi type 1

Is there any way to do like this? (maybe using delegate?)

Hello guys, is there any way to run stop mapping the items when the first non null item is found? Doing that in a simple for loop would be obvious, but I would like to make use of kotlin collection operators. This question applies to the

ConfigValidator.validate

method. Any other comments or possible improvements to the code below are also welcome. Thanks!

class ConfigValidator(private val configRules: List<Rule>) {
    abstract class Rule {
        abstract fun validateConfig(model: InitModel): RuleViolation?
    }

    fun validate(model: InitModel) = configRules.map {
        // !!! is there any way to make this stop mapping items when the first RuleViolation is found? !!!
        // this method needs to return "RuleViolation?"
        it.validateConfig(model)
    }.firstOrNull()

    class SimpleRule1(...) : Rule() {
        override fun validateConfig(model: InitModel): RuleViolation? =
            model.items.firstOrNull {
                // some condition for model item
            }?.let {
                RuleViolation(1, "Rule violation description")
            }
    }

    class SimpleRule2(...) : Rule() {
        override fun validateConfig(model: InitModel): RuleViolation? =
            model.items.firstOrNull {
                // some condition for model item
            }?.let {
                RuleViolation(2, "Rule  2 violation description")
            }
    }

    class RuleViolation(val code: Int, message: String) : Exception(message)
}

What pro book do you suggest about kotlin? I know kotlin well, but I want to know it better.

Anyone else seeing failures with gradle publishing and 1.5.20?

Getting this new warning after updating to Kotlin 1.5.20:

JvmField cannot be applied to a property of an inline class type. This warning will become an error in further releases

I didn't see this mentioned anywhere in the release notes (or the GitHub release). Is there something pointing to this?

Hello! I'm not sure if this has been asked before but I have found few issues on YouTrack but they haven't really gone further than just that. Anyways, currently in Kotlin there is no way to assign integer value to Double type variables or use integer in place where Double is expected instead you have to explicitly add a decimal point. Is there anything planned regarding this or is this open for contributors maybe?

How can I best connect ktor to the postgresql database and then my Android project

Hi To improve my Kotlin skills, I'm looking for an open source project I could be able to contribute to any suggestions ?

Question about value classes (I'm familiar with the old inline classes but it has been a while): I was under the impression value classes, like inline classes, behave with respect to the compiler like the wrapped class. So why is the following invalid?

@JvmInline
value class Bar(
   val foo: Foo
)

fun Foo.doSomething() {
}

ERROR HERE >>> Bar(Foo()).doSomething()

Hi team, Kotlin beginner question here, created a new package in Kotlin Project, but its not allowing me to use Kotlin basic function such as println,

hi, do you have lag with Android Studio on M1 Mac? I’ve just installed Android Studio on M1, and feel performance not good as with Intel Mac.

Any Kotlin Pro available for 15 min call? Have some basic beginner questions around IntelliJ