kotlinlang #announcements

Hi everybody, I was wandering why in IntelliJ with Kotlin it’s impossible to do some refacto actions (like in Java). For example, I can’t do Move a class method into an other Class. Please look at my screenshot below.

Adam Kirk

03/22/2019, 3:52 PM

Hello everyone, thank you for allowing me to join, hopefully I won’t have too many questions. 🙂 Learning Kotlin has been a blast and I am looking forward to all the great things I can do with it.

👋 7

👍 1

Kirill Zhukov

03/22/2019, 10:57 PM

How come Java’s

BigDecimal#intValue()

is not accessible from Kotlin? 🤔

Davide Giuseppe Farella

03/23/2019, 4:59 PM

I have the following

typealias

on a lambda:

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typealias ErrorStateGenerator = ErrorStateFactory.(Throwable) -> ViewState.Error

ErrorStateFactory

provides a

default

val. This is a typical use case:

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ViewStateStoreConfig.errorStateGenerator = {
    when( it ) {
        is NullPointerException -> NPError( it )
        is IllegalArgumentException -> IAError( it )
        else -> default
    }
}

I was wondering a common scenario where the user only got some dependencies ( exceptions ) in certain modules, so this would be helpful:

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ViewStateStoreConfig.errorStateGenerator = 
        generatorFromThisModule + generatorFromModule2 + generatorFromModule3

So I would need a class for wraps the `ErrorStateGenerator`s; this class should extend

ErrorStateGenerator

itself, but is not possible since

ErrorStateGenerator

is an extension function… Which solution would you suggest?

Davide Giuseppe Farella

03/23/2019, 5:01 PM

This_is_my_current___NOT_WORKING___solution.kt

Davide Giuseppe Farella

03/23/2019, 5:25 PM

Ok_I_managed_to_do_that_with_and_even_simpler_lambda___.kt

sitepodmatt

03/25/2019, 2:16 AM

how do I access a kotlin annotation on a lambda

juliocbcotta

03/25/2019, 5:33 AM

Hello, I am struggling with a problem here, maybe you can help. I have an interface and many enums that implement that interface. I need a way to do something like a

valueOf

to get a reference of a enum entry from a string. As I don't know which enum to look at I would have to go through all implementations or use something like "$EnumClass.$EnumEntry" string. Maybe I can use some reflection? Any ideas?

Jan Gerling

03/25/2019, 11:07 AM

While reading through pull requests on GitHub, I noticed many of the pull requests were merged manually, for example https://github.com/JetBrains/kotlin/pull/398 or https://github.com/JetBrains/kotlin/pull/349. Why are many pull requests merged manually, instead of merging them with GitHub?

standinga

03/25/2019, 1:16 PM

hey guys! what is the best way to pass callback inside init ()

standinga

03/25/2019, 1:17 PM

ie. I'd like to have my listener "val"

rook

03/25/2019, 4:09 PM

I’m curious if there’s a way to filter lists of parent class by child class and actually change the type signature to reflect that the new list only contains elements of the child type filtered

-.kt

karelpeeters

03/25/2019, 4:10 PM

filterIsInstance<First>()

💯 2

rook

03/25/2019, 4:10 PM

Thank you!

wck

03/26/2019, 4:28 AM

Hi, I’m getting a weird production crash

wck

03/26/2019, 4:28 AM

According to

<https://android.googlesource.com/platform/art/+/6027871fa3bb32f01ee2f1560e1967d986871c18/runtime/class_linker.cc>

FindPrimitiveClass

the class descriptor indicate it is a primitive type but in reality it is not. How is this possible? Posted in #android

Kompass

03/26/2019, 5:38 AM

Untitled.kt

user

03/26/2019, 7:23 AM

https://twitter.com/kotlin/status/1110442156492095488 Dokka 0.9.18 is here! This bugfix release comes with a few improvements and changes: https://github.com/Kotlin/dokka/releases/tag/0.9.18 Twitter

Hamachi

03/26/2019, 10:41 AM

Nice to meet you,everyone!

👋 8

Hamachi

03/26/2019, 10:42 AM

I will deepen my knowledge of programming with Kotlin!

Sebastian Krajewski

03/26/2019, 6:57 PM

Hi, i can't find anything about that in Kotlin Style Guide. What's better, 1 or 2?

1or2.kt

03/26/2019, 6:59 PM

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check(!disposed) { "Can't bind disposed VBO" }
check(!isBound) { "VBO is already bound" }

🤯 6

➕ 8

Sebastian Krajewski

03/26/2019, 7:09 PM

Thanks, never thought about builtin preconditions. I thought that IDEA would have recommended that by Intentions