kotlinlang #getting-started

I dunno where to ask this question, though... Oracle's Java SE 11 implementation is called Oracle JDK, while the same things for Java SE 8 were called either JDK, JRE Server, or just JRE, depending on packaging. Why for Java SE 11 they add Oracle prefix to their JDK/JRE (as well as to Oracle OpenJDK)? How to refer to Oracle's distribution of Java SE 8 -- just JDK/JRE?

Slava Kornienko

10/22/2018, 10:52 PM

Привет! Как можно логировать тело запросов? Кроме их метода и пути

Slava Kornienko

10/22/2018, 11:01 PM

Sorry, I thought it was ktor slack

pavel

10/23/2018, 6:12 PM

doesn’t work on try.kotlinlang.com with JVM and 1.2.71

jacob

10/24/2018, 5:05 AM

#arrow will likely get you more eyes on the question @vejeta

Sudhir Singh Khanger

10/25/2018, 5:51 PM

CHEESE_DATA.map { Cheese(id = 0, name = it) }

CHEESE_DATA

is an ArrayList. If we apply

map

with the above function then should it not create a list of Cheese objects with id

and name

it

. The result seems to be Cheese object with an incremented value for id and

it

name. What am I missing? https://github.com/googlesamples/android-architecture-components/blob/6248bed977e7a82d6f3199e8a940a39b7d6f051c/PagingSample/app/src/main/java/paging/android/example/com/pagingsample/CheeseDb.kt#L54

mics

10/25/2018, 5:58 PM

Hi, I’m looking for a way around a compilation error when interacting with specific Java code. I have a preexisting Java code (in a library, which I cannot change and need to consume) the code like this

class Foo<T extends Enum<T>> {
  Foo(Class<T> type) {}
}

enum FEnum {
  BLAH
}

and then I try to instantiate

Foo

in Kotlin

fun main(args: Array<String>) {
    val foo = Foo(FEnum::class.java) // works ok, but have to hard-code enum class name here

    val type: Class<out Enum<*>> = FEnum::class.java
    val bar = Foo(type) // Error: doesn't work when class is obtained dynamically 
}

How can I modify the Kotlin code, passing

type

as some

Class

, so that

Foo

constructor accepts it?

Steven McLaughlin

10/26/2018, 7:43 PM

I am working on a small project for fun, and I'm having a little trouble with setting things up with gradle/kotlin 1.3. (Going to post more in a thread so I don't spam the channel)

karelpeeters

10/29/2018, 3:03 PM

list.fold(mapOf()) { a, c -> a + c }

jasoet

10/30/2018, 1:34 AM

If anyone interested boilerplate Kotlin Project using Gradle you can use this https://github.com/jasoet/kotlin-gradle-boilerplate Update to Kotlin 1.3.0

Enrico Hofmann

10/30/2018, 12:36 PM

hi togeth i am a java developer. and i will hove something like nullable/optional in a data class. how can i do that ?

prabello

10/31/2018, 11:57 AM

i tried doing

let{::loveThePet}

but the return end up beign different and could not chain the calls, they were returning a KFunction instead of the result

Matheus

10/31/2018, 12:00 PM

or let(::loveThePet)

☝️ 2

jcechace

10/31/2018, 1:21 PM

Any hints how to properly configurate shadow plugin? Getting these errors and since I have very limited experience with gradle and shadow plugin it’s not clear wha’t wrong (except for that some things are obviously missing) https://gist.github.com/jcechace/96e8dd2801b677a50a87cebb42e81748

oday

10/31/2018, 1:52 PM

ahhh

epchris

10/31/2018, 3:57 PM

(I feel like this is a real newb question….)

prabello

10/31/2018, 7:16 PM

Does lazy initialization variables have an especific order?

Sudhir Singh Khanger

11/01/2018, 6:26 AM

How does

val that : Int -> Int = { three -> three }

fit the definition

val lambdaName : Type = { argumentList -> codeBody }

? https://www.baeldung.com/kotlin-lambda-expressions

Gabriel Machado

11/01/2018, 2:11 PM

What happens when a function is overriden by a inline function? The compiler warns

Override by an inline function

, does this means it won't be inlined?

oday

11/01/2018, 7:56 PM

what’s a kotliny way of using

find

to find the one and only item in a list where I know there is no repetition with, according to its ID?

Hamza

11/02/2018, 5:26 AM

i’ve completely forgotten and i can’t remember how/find anywhere onlein, but how can i add a compiler argument via gradle dsl? i can’t remember for the life of me

dvlwj

11/02/2018, 8:25 AM

ktor?

dvlwj

11/02/2018, 8:41 AM

is it bad ? i found people saying they are prefer retrofit or okhttp over Fuel.

Jimmy

11/02/2018, 10:05 AM

Hello all, I have a question regarding “find{ }” . I checked the code in stdlib and it returns the element or null. I want to return true/false when iterating over a list and certain condition is met. This is what I thought (I bet there is a better way to cover the null case...), any idea??? :

-.kt

Matouš Skála

11/02/2018, 10:44 AM

What's currently the recommended way for creating a Kotlin/Native module that would be used both as an iOS framework and an Android library? After some research, I have found there are three Gradle plugins that I can use: 1. konan (https://kotlinlang.org/docs/tutorials/native/gradle-for-kotlin-native.html) 2. platform.native (https://kotlinlang.org/docs/reference/native/gradle_plugin.html) 3. multiplatform (https://kotlinlang.org/docs/reference/building-mpp-with-gradle.html)

bodiam

11/02/2018, 11:10 AM

anyone a suggestion on how to fix this?

bodiam

11/02/2018, 12:07 PM

Try Math.min(2,3)

ValV

11/03/2018, 10:23 AM

Why sometimes IDEA shows file extensions .kt? Is this because it does not find a class with the same name inside?

scottiedog45

11/03/2018, 10:28 AM

Hi everyone! Happy to be here. I have a background in web and iOS but I’m completely new to kotlin. Is kotlin to java as swift is to objc? Are the development environments similar? Is there an xcode parallel for kotlin?

ckchen

11/03/2018, 12:44 PM

I am learning coroutines and I got confused when I see the code

coroutineContext[Job]

. Isn’t

Job

an interface? Why can it be used for indexing? I have checked the source (

public operator fun <E : Element> get(key: Key<E>): E?

CoroutineContext

) and still don’t have a clue.

Title

ckchen

11/03/2018, 12:44 PM

I am learning coroutines and I got confused when I see the code

coroutineContext[Job]

. Isn’t

Job

an interface? Why can it be used for indexing? I have checked the source (

public operator fun <E : Element> get(key: Key<E>): E?

CoroutineContext

) and still don’t have a clue.

karelpeeters

11/03/2018, 12:49 PM

What happens when you do

Ctrl+B

Job

ckchen

11/03/2018, 12:50 PM

public interface Job : CoroutineContext.Element

I mean,

Job

is an interface, not an instance of

Key<E>

. Why can it be passed to

public operator fun <E : Element> get(key: Key<E>): E

karelpeeters

11/03/2018, 12:54 PM

Dammit I remember reading about this, I completely forgot though. You might have more luck asking in #coroutines

elizarov

11/03/2018, 12:57 PM

It is called companion object.

https://kotlinlang.org/docs/reference/object-declarations.html#companion-objects

karelpeeters

11/03/2018, 1:01 PM

Huh might be misremembering then, wasn't there something special about

[Job]

ckchen

11/03/2018, 1:04 PM

I see this

public companion object Key : CoroutineContext.Key<Job>

Job

. So, why not

coroutineContext[Job.Key]

elizarov

11/03/2018, 1:05 PM

You can use

Job.Key

. But since

Key

is a companion object to

Job

, simply using

Job

works, too.

ckchen

11/03/2018, 1:06 PM

Is this a hidden secret? 😀 I don’t see it addressed in the document of companion objects.

karelpeeters

11/03/2018, 1:08 PM

They explain it the other way around, first with a custom name and then "you can omit it".

ckchen

11/03/2018, 1:11 PM

I know. But I thought they are talking about calling the method of the companion object. I didn’t expect that we can refer to the companion object by omitting it and just use the class name.

elizarov

11/03/2018, 3:31 PM

Indeed, it is not explicitly spelled in the docs. It would be nice to add such an example there

ckchen

11/04/2018, 12:52 AM

Yes. So I made a simple pull request yesterday (https://github.com/JetBrains/kotlin-web-site/pull/1192). Hope it would be helpful.

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