Hi guys, Today I noticed weird problem on equals() function it basically; class Event(val endTime: Long?){ fun isGoingEvent() = ((endTime == null) || endTime?.equals(0)) } Event(0L).isGoingEvent() ----> returns false if I change isGoingEvent() implementation with: fun isGoingEvent() = ((endTime == null) || endTime?.equals(0L)) it works as expected. It make sense because it compares Long with Long but I confused how should I compare values?

Hello, I found actual source for kotlin-eap On bintray I found https://bintray.com/kotlin/kotlin-eap this, and in top right corner there is link on https://dl.bintray.com/kotlin/kotlin-eap But additionally I found out another one https://kotlin.bintray.com/kotlin-eap/ What link is preferable?

why

@JvmName

cant do anything here?

@JvmName("getI") fun get(): Int = 0
    @JvmName("getF") fun get(): Float = 0f // error, signature clash

I want to have non exhaustive when's on a sealed classes to be an error, is that possible somehow?

Does Kotlin support a kind of duck typing? Because according to koans, one can simply define extension method

operator fun MyDate.rangeTo(other: MyDate): DateRange

and it will work without implementing any interface.

I read this https://blog.mindorks.com/learn-kotlin-apply-vs-with But still can not understand the differences between

apply

and

with

. When should I use one over the other?

Hello, i try convert this cURL in kotlin using retrofit 2, but i cant and i really need this. Help me please. Code cURL-> curl -X POST \ URL_BASE\ -H 'Authorization: Bearer <your_acces_token>'\ -H 'content-type: application/json'\ -d '{ "process": "Attended", "rauthorityId": "<your_rauthorityId>" }'

Is it the same for you that this shows no warning in the IDE but crashes the compiler?

Actually I had to add

fun MutableEntity.postSomething() = postSomething

class Dummy {
    fun foo() = println("Hi")
}
fun Dummy.apply(f :Dummy.() -> Unit) = f()
Dummy().apply({ foo() })

How does

Dummy.() -> Unit

know how it needs to dispatch the function call?

Is there any way that I can use

<reified T>

with a

sealed class

?

I’ve been reading on composition over inheritance in Kotlin and came across a few articles like this https://medium.com/the-kotlin-chronicle/why-you-should-use-class-delegation-in-kotlin-fb0a3ebf151e One way Kotlin helps to reduce boiler plate code is by using class delegation and the

by

keyword. This looks great and I like it so far. However, during the closing panel of KotlinConf 2018, Andrey and another guy said it was their least favourite feature. Does anyone have any opinion or bad experience with class delegation?

Hey guys. So, i Have a abstract class in Java that has a abstract method like this:

public abstract class MyClass implements MyInterface {
    @Override
    public abstract <M extends MyInterface> MyModelType<M> getModelType();
}

How do i implement this in Kolin? i always get this:

override fun <M : MyInterface?> getModelType(): MyModelType<M> {
        TODO
    }

but this is not what i want, in Java works fine

@Override
    public MyModelType<MyClassImpl> getModelType() {
        return null;
    }

Any ideas on how to do it?

i guess that's the real question: can i create an inline class whose value can be modified in place to implement something like

inlineClassInstance++

to increment its value

What version of Java do people here compile their Kotlin to?

in particular i am unable to instance lexer(...) itself from inside the clone() function

in fact, it's just trying to access

Sub.member

that causes the ClassCastException

This message was deleted.

what does @ do, as i cant find its documentation in the kotlin-docs.pdf

I am working on generic data-access library (for example for accessing your SQL database) inspired by the great model system in Django (Python). The general idea is that you write your database models like this:

object UserModel : Model {
    val name by VarcharField()
}

From that I am doing to generate code like this (using an annotation processor):

data class User(val name: String)

If I now have a call like

dataSource.findAll(UserModel)

how can I express to the compiler that this returns

List<User>

?

So kotlinx.time is in the design phase at the moment iirc. How are the logging and fileIO libs progressing?

as im trying to find a way to instance my classes in a way that is local to the parser class, such that when parser().clone() is called, all instances associated with parser() are reassigned to the new parser() returned by clone(), so i do not need to recreate my instances every time i clone my parser

is it possible to create different callbacks based on an enum type?

on(Event.TYPE_ONE) { int ->
    // an int is available here
}

on(Event.TYPE_TWO) { string ->
    // a string is available here
}

Im teaching my non-technical coworkers programming 101 with Kotlin, followed by android development. Can anyone recommend me some slides, material or tips for doing this? Most reference material for Kotlin is Kotlin for Java developers. Thankyou in advanced!

According to the building web app with spring boot and kotlin tutorial, there is a spring channel. But does not appear to be in the list of channels. Am I missing something?

I know about infix operators, as well as typealias in Kotlin, but my understanding is that I wouldn’t be able to do something equivalent in Kotlin. We can’t overload or change the keywords at all. Right?

Why can’t I pass a value of type

Map<String, String?>

as parameter of a function taking

Map<Any?, *>

? I assume I can safely do an unchecked cast here, but I wonder why I need it at all