kotlinlang #announcements

📣 Hey everyone! Just a heads up: we have a somewhat unfortunate regression in 1.3.20 regarding function names. If you use function names with a right parenthesis character

(which is common in test code) you might encounter a compiler crash with a stack trace that ends in something like

IllegalArgumentException at getAbstractTypeFromDescriptor

. Here's the issue: https://youtrack.jetbrains.com/issue/KT-29475 . To avoid the crash just remove the

from the offending function name. We'll try to come up with a way to fix this.

Dalinar

01/26/2019, 8:11 PM

if i pass a

varargs args

to another fun accepting a

varargs

then I must pass it as

*args

.. but what about java, if I'm calling a kotlin fun expecting to be passed a

varargs

from java then I should just send it as

kotlinfun(args)

Vishal

08/07/2019, 5:40 AM

Hi All,

👋 1

Vishal

08/07/2019, 5:43 AM

only these folders are getting generated, see attached image.

tschuchort

08/07/2019, 9:25 PM

I'm working on something like a compiler that transforms the ASTs of two different languages into a shared IR/AST. I have defined this IR as a deep hierarchy of sealed classes where the leaves are abstract. My plan was to make implementations of those abstract leaf classes for each of the two langauges (i.e. the

ClassElement

is implemented as

AClassElement

if it was converted from source langauge A or

BClassElement

if it was converted from source language B and the conversion happens mostly in the constructors). They are essentially data classes but many properties have to be computed lazily. My problem is how to reuse the construction code for related AST elements. For example,

ClassElement

and

InterfaceElement

both extend

ClassLikeElement

and share a lot of properties. Usually I could put the shared logic into

ClassLikeElement

and inherit it, but here it doesn't work because the implementations for

ClassLikeElement

need to be different for source languages

and

. My options are: 1. Put the shared logic into delegate objects and make two implementations of every AST element for the source languages

and

2. Make the AST classes pure data classes and do all the conversion in a factory. 3. Mix both options? Which approach is preferable?

karelpeeters

08/08/2019, 7:53 AM

There's no real "hierarchy", the type is the explicitly specified type unless you don't have one and then it's inferred.

jermainedilao

08/08/2019, 7:53 AM

This is not a big deal but I just want to have a deeper understanding about this 😅

bhavin

08/08/2019, 8:59 AM

Marc Reichelt

08/08/2019, 2:10 PM

Hi! I’m doing a talk next week called Kotlin’s companion object: The power of IntelliJ IDEA, in which I want to show some nice features of IntelliJ that help us being more productive. I already have some ideas, but I created the channel #intellij-tricks because I believe there are so much more IntelliJ tips that I don’t know about, but are really useful – especially for developing with Kotlin! 💪 So, what are your favorite tips & tricks for doing Kotlin development? Please post them in #intellij-tricks, so we don’t spam the general channel 😇

thana

08/08/2019, 2:19 PM

is there a way to debug a

gradle assemble

somehow? during the compilation the the kotlinx.serialization plugin generates bad bytecode and throws an exception. i'd like to break excactly there so find out what excactly is bad, but im clueless how to do that (breakpoint on all exceptions didn;t do the trick)

Adam Spofford

08/08/2019, 5:14 PM

aloha

Adam Spofford

08/08/2019, 5:15 PM

got a thread on the forums about compiler plugins, where the compiler plugin is being invoked correctly but the code never actually gets called

Adam Spofford

08/08/2019, 5:15 PM

https://discuss.kotlinlang.org/t/compiler-plugin-not-being-called/13136

rrader

08/08/2019, 8:53 PM

Is someone using https://github.com/zalando/logbook for logging request/response ?

bostonmacosx

08/10/2019, 4:07 AM

Having issues with this callback...

Untitled

jkbbwr

08/11/2019, 1:10 AM

Im trying to use gradle.kts + intellij + antlr together but im getting some weird ass gradle errors

jkbbwr

08/11/2019, 1:10 AM

Copy code

e: /home/jakob/projects/personal/reactor/src/main/kotlin/dev/kibb/reactor/main.kt: (11, 19): Unresolved reference: UraniumBaseListener
e: /home/jakob/projects/personal/reactor/src/main/kotlin/dev/kibb/reactor/main.kt: (17, 17): Unresolved reference: UraniumLexer
e: /home/jakob/projects/personal/reactor/src/main/kotlin/dev/kibb/reactor/main.kt: (18, 18): Unresolved reference: UraniumParser

jkbbwr

08/11/2019, 1:10 AM

image.png

jkbbwr

08/11/2019, 1:10 AM

The package is correct for those files also

jkbbwr

08/11/2019, 1:11 AM

Copy code

import org.jetbrains.kotlin.gradle.tasks.KotlinCompile

plugins {
    kotlin("jvm") version "1.3.41"
    antlr
}

group = "dev.kibb"
version = "1.0-SNAPSHOT"

repositories {
    mavenCentral()
    maven(url = "<https://dl.bintray.com/hotkeytlt/maven>")
}

dependencies {
    antlr("org.antlr:antlr4:+")

    implementation(kotlin("stdlib-jdk8"))
    testImplementation(kotlin("test"))
    testImplementation(kotlin("test-junit"))
}

tasks.withType<KotlinCompile> {
    kotlinOptions.jvmTarget = "1.8"
}

tasks.generateGrammarSource {
    arguments.addAll(listOf(
        "-package", "dev.kibb.reactor"
    ))
}

jkbbwr

08/11/2019, 1:11 AM

This is my KTS

jkbbwr

08/11/2019, 1:52 AM

FYI it was an issue with the directory structure it was src/main/antlr/dev.kibb.reactor NOT src/main/antlr/dev/kibb/reactor

Iaroslav Postovalov

08/11/2019, 9:35 AM

Daniel

08/11/2019, 12:48 PM

Hmm was there a change with

Copy code

androidExtensions {
    experimental = true
}

? I IDE cant resolve `@Parcelize`even through it should with the experimental = true

Daniel

08/11/2019, 12:58 PM

Interesting solution: https://github.com/gradle/kotlin-dsl/issues/644#issuecomment-354728070 ->

Copy code

Just apply the kotlin-android plugin before the
kotlin-android-extensions and it should work...

haroldadmin

08/12/2019, 5:56 AM

Hi! I have been trying to create a call adapter in Retrofit for suspending functions that return a sealed class type. Something like this:

Copy code

@GET("/")
suspend fun getSomething(): MySealedClass<SuccessType, ErrorType>

On a Reddit discussion thread, Jake left some instructions on how this could be done: https://www.reddit.com/r/androiddev/comments/c6m3yv/network_request_wrapper_extension_for_retrofit_26 Here's the relevant part:

suspend fun whatever(): Whatever
will ask Retrofit for a CallAdapter to handle
Call<Whatever>
. Knowing this, you can register a
CallAdapter.Factory
which looks for
Call<YourSealedClass<BodyType>>
, delegates to the built-in factory for
Call<BodyType>
, and then wraps the value in
YourSealedClass
. This will allow
suspend fun whatever(): YourSealedClass<Whatever>
to work–no extension needed.

I am unable to figure out how to do the delegation part. I have a call of the type

Call<MySealedClass<SuccessType, E>>

, and need to find a delegate which can adapt

Call<SuccessType>

. More specifically, I can not figure out how to create a Parameterized Type Token for

Call<SuccessType>

so that I can pass it to retrofit to find the delegated adapter for me. I would really appreciate some help with this.

haroldadmin

08/12/2019, 6:38 AM

All existing examples I can find for Retrofit call adapters convert from

Call

to another Future-like type. I don't know how to add a call adapter that can convert from

Call<Type1>

Call<Type2>

Kavin

08/12/2019, 11:43 AM

Can we break the

forEachIndexed

loop in Kotlin? While iterating the array, I want to break it based on a specific condition is met. I have tried

break

but getting compile time error break and continue are only allowed inside a loop. Using

return

just skips that specific index but continues the loop. Does it mean we cannot

break

forEach

forEachIndexed

Big Chungus

08/12/2019, 11:55 AM

Since foreach is just a function with lambda argument, you cannot break or continue it. All it does is invokes your lambda on each element

👎 1

👍 1

corneil

08/12/2019, 12:03 PM

Sounds like you may want to do a

filter

find

before the

forEach