how would you and extension function that removes a bunch of characters from a String?

Fun String.removeChars(allTheCharsToRemove: String): String

there is the String.replace(regex, replacement) that you could call with

""

as second parameter. So I’d have to create a Regex from my

allTheCharsToRemove

(how? if that’d be your approach) or is there a better way?

Considering :

inline fun <T> List<T>.applyOnEach(block: T.() -> Unit): List<T> = onEach { it?.block() }

Is there a way to mark the receiver in

T.() -> Unit

as not nullable?

Does anyone here use Kotlin for mobile development?

So what are the plans for 1.4? Is there somewhere I can read about the new IR and other significant changes?

assuming that you have a typical module (repository, model, config and other stuff) do you expose the model class (the one you use in repo) or a DTO through a service/facade?

Hello, World! I'm looking at the kotlin.time package. I see there's a

Duration

abstraction but what about a Moment (aka, Date or Time stamp, or a point in time)? Is that what

ClockMark

represents?

What do you guys think about this kind of naming?

typealias SessionId = String
typealias TopicName = String
fun unsubscribe(who: SessionId, from: TopicName) {..}
fun subscribe(to: TopicName, handler: (Topic) -> Unit)

Hi Guys. I am just trying out Multiplatform. I wanted to write a multiplatform library that connects to a P*ayment API*. The library should work on all platforms (Android, iOS, Windows, Javascript e.t.c). Any ideas on how I should go about this?

i did understand continuation , context but unable to understand these

co-routine scopes

for coroutines can someone explain me in

layman

terms. builders are used to create coroutines dispatchers to alter context.

kotlin/native serialization

Cannot infer type parameter

what should i do at

Serializer

line

31

? https://github.com/AlexanderShniperson/KotlinNativeSerialization

If all I want from reflection is

any::class.simpleName

, does that still require including the Kotlin Reflection jar?

Why doesn't

package kotlin.reflect.jvm.internal.calls.Caller.checkArguments(args: Array<*>)

respect functions with default parameter values? I don't want to include it in

func.call(..., "alreadyHasADefaultValue")

, and am stopped by

throw IllegalArgumentException("Callable expects $arity arguments, but ${args.size} were provided.")

there's a method which takes a @FunctionalInterface as a parameter. I can see that passing a lambda like

.filter{req: ClientRequest, next: ExchangeFunction ->
    // do something
}

works. However, what I'd like to do is pass a function reference instead of the lambda so that I don't have to actually put 50 lines of code inside the

.filter

call. I'm quite new to Kotlin and I have a very fragile understanding of higher order functions, so I have no idea how to achieve this. I thought making the method like this -

private fun customFilter(request: ClientRequest, next: ExchangeFunction){

}

and calling like

.filter(::customFilter)

would work, but it didn't - IDE tells me

Type mismatch.
Required:
ExchangeFilterFunction
Found:
KFunction2<@ParameterName ClientRequest, @ParameterName ExchangeFunction, Unit>

It seems like I have to somehow implement the ExchangeFilterFunction.java which is a java

@FunctionalInterface

...? Any advice is appreciated

What is more performant: 1.

days.groupBy { it.date.year }.forEach { (year, daysOfYear) ->
    daysOfYear.groupBy { it.date.month }.forEach { (month, daysOfMonth) ->
      aysOfMonth.groupBy { it.date.weekNumber() }.forEach { (week, daysOfWeek) ->
}}}

2.

days.groupBy { Triple(it.date.year, it.date.month, it.date.weekNumber()) }.forEach { (triple, days) ->
}

Is there a recommended Kotlin library that focuses on geometry?

i dont want to make caller have suspend the function on call to my function.

Hi Kotlin folks, is there any library or compiler plugin available to generate builders (java compatibility is very important) from Kotlin Data classes. SO has a lot of suggestions for this problem, but most of them requires way more boilerplate than expected.

Hey friends, Is there a point in reading Effective Java, with the movement to Kotlin?

Are kotlin SAM types Serializable? eg

() -> Unit

Is there a Kotlin way of locale-specific sorting?

fun sort(list: List<String>): List<String> {
    val collator = Collator.getInstance(Locale.GERMAN)
    collator.strength = Collator.PRIMARY
    return list.sortedWith(Comparator {a, b -> collator.compare(a, b)})
}

What's the correct way to import and use a DLL in kotlin and intelliJ using modules?

Hey, is there a way to disable build warnings for a specific warning type? Eg. I would like to disable all

EXPERIMENTAL_API_USAGE

warnings in my project build log

Is it possible to have the following:

abstract class A<T : A<T>>(
    val id: Id<T>
)

class B(id: Id<B>) : A<B>(id)
class C(id: Id<C>) : A<C>(id)

I want to have polymorphism in a DB model, and the library provides type safe

Id

with generics. I want the superclass to have the id property and to restrict it to be of any subclass of itself. For this I have the

A<T : A<T>>

definition on top. Now, a subclass passes in its own type and only allows id to be of that type, making sure I never have

Id<C>

in a

B

class. But when trying to use that type system, I have the problem of recursive definition of the parameter of A. For example when mapping a list of instances of objects holding subclasses of A, I need to specify the type variable like this:

SomeClassHoldingASubclasses(…)

=>

SomeClassHoldingASubclasses<A<A<A ... > > >

It is not possible to do it like this:

SomeClassHoldingASubclasses<*>

“projections are not allowed on type arguments of functions and properties” If I remove the type variable from A, I cannot pass an id : Id<B> to the constructor of A. I’m trying to get this to work for quite some time now, but are these polymorphic / self-referencing type variables even possible? Should I use

in

or

out

(I tried but that also went weird fast)?

I'm getting this crazy

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

exception while trying to compile my code after updating some Gradle dependencies to their most recent version: https://gist.github.com/sanity/d4d0a84155a52a26c09386b0cf9a9e27 Anyone have any ideas what it might be? Unfortunately it's blocking progress on my project.

Hello, I have such method in a library:

open fun track(event: String, properties: Map<Any?, *>?, options: Map<Any?, *>?): Unit

How can I create a map that would have satisfy

properties

type?

What is difference between

Transformations.map

and

Livedata.map

? Which one is better ? And what is usecase for it?

pls suggest any kotlin/native multiplatform logger

Hi guys. How can I override a variable of a derived interface type. I have the interfaces:

interface ExperimentManagerDelegateCore {

interface ExperimentManagerDelegate:ExperimentManagerDelegateCore {

I have the classes:

abstract class ExperimentManagerCore {

    open var delegate: WeakReference<out ExperimentManagerDelegateCore>? = null
}

class ExperimentManager():ExperimentManagerCore() {

    override var delegate: WeakReference<ExperimentManagerDelegate>? = null
}

but in

ExperimentManager

I got the error:

Type of 'delegate' doesn't match the type of the overridden var-property 'public open var delegate: WeakReference? defined in ExperimentManager.ExperimentManagerCore'

I thought I would fix it with

out ExperimentManagerDelegateCore

Any ideas?

how do you write java

0x1p10

in kotlin?