kotlinlang #announcements

I have a few functions that do some database stuff. Of course I want to run them async, how should I do it? Add the suspend keyword to the function and then call the functions with an async block?

curioustechizen

04/27/2017, 4:12 PM

Is there are more elegant/idiomatic way of writing this code? That

!!

- while valid here because I checked for null before, doesn't seem idiomatic to me

kevinmost

04/27/2017, 4:16 PM

thing?.takeIf { anotherCondition }?.run(::doSomething)

I believe would work

👍 4

uujava

04/27/2017, 4:33 PM

Hi, I have a general question. Say I have a feature request for Kotlin compiler. What is proper process to submit it for review or discussion?

mg6maciej

04/27/2017, 8:58 PM

Speaking of reflections. Anybody knows if there is a library for diffing data class objects?

snowe

04/27/2017, 9:45 PM

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val events= mapOf(
        Pair("Applicant Created", { projector.handle(applicantCreatedEvent()) }),
        Pair("Property Registered", { projector.handle(propertyRegisteredEvent()) }),

mg6maciej

04/27/2017, 9:52 PM

I'll push it as feature request. Maybe inferring type from map is something that can be done.

Czar

04/28/2017, 7:01 AM

Seems, while I was sleeping, you guys found some way to solve the problem we were talking about 🙂 My idea was to implement visitor:

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class Projector {
    fun <T:LoanTransactionEvent> handle(event: T) {
        event.handleWith(this)
    }
}

interface LoanTransactionEvent {
    default void handleWith(Projector projector) {
        // your event-specific stuff here
    }
}

And now you can call it in the loop exactly as @snowe wanted. (I was too lazy to test, so there may be some mechanical errors).

chris-hatton

04/28/2017, 8:36 AM

I was missing that functionality a lot from swifts enums, and though I'd heard the term 'sealed' classes I'd somehow thought it just meant 'final'...

dmitriy.govorukhin

04/28/2017, 2:23 PM

Hi guys, i have a question about coroutine serialization. Is it already implemented or not? i can't find any example. I just find this discussion https://github.com/Kotlin/kotlin-coroutines/issues/28, but last comment was more than six months ago.

xenomachina

04/28/2017, 6:19 PM

I have a project where upgrading to Kotlin 1.1.2 (from 1.1.1) causes Travis CI to fail with "Failed to apply plugin [id 'kotlin']". It builds fine on my own machine. builds: https://travis-ci.org/xenomachina/xenocom/builds source: https://github.com/xenomachina/xenocom Is anyone else seeing something like this?

yoavst

04/29/2017, 10:49 AM

Why does the link to source here https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/to-string.html points to the native source and not jvm source?

mibac

04/29/2017, 5:14 PM

Hello! How can I get `KCallable`'s all parameters' types? (I need a Java's

Class

)

stackoverflow 1

snrostov

04/29/2017, 5:59 PM

Is there any way escape $ in raw string literal? example:

println("""  $d  """)

how escape $? this doesn't work:

println("""  \$d  """)

chris-hatton

04/30/2017, 6:38 AM

KClass doesn't even have Java Class's

isInterface

equivalent.

kkozmic

04/30/2017, 8:37 AM

Any better option @mg6maciej ?

kkozmic

04/30/2017, 12:05 PM

what's the difference between $kotlinVersion 1.1.2-2 and 1.1.2 ?

orangy

04/30/2017, 5:31 PM

Oh and obviously figure out the API for each version multiple times a year…

🙂 4

pniederw

05/01/2017, 1:57 AM

@iferca the maven plugin should have a configuration option equivalent to the ‘-jvm-target’ command-line option. default is probably 1.6.

deepanshu

05/01/2017, 9:21 AM

Is the bytecode shown by Intellij the final bytecode produced by the kotlin compiler, or is it optimized further? As an example, the following code was produced by the Intellij

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(0..listA.size - 1).filter{ listA[it] < listB[it] }.forEach { return true}; return false

as a result of intention action to fix "LoopToCallChain` warning on the following loop:

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for (i in 0..listA.size - 1) if (listA[i] < listB[i]) return true; return false

The bytecode in the IDE of former snippet shows creation of additional objects, and more importantly, running the comparison for the full list, rather than returning early. Does the compiler at build time optimize it?

mg6maciej

05/01/2017, 12:13 PM

@Czar I think test code should derive defaults from prod here, I've reported it as problematic.

Daniel

05/01/2017, 12:14 PM

Good day madams/sirs. This is the first time I am in this chat and I just wanted so say a huge thanks to the makers and contributors of kotlin! Its such a wonderful language and for a android developer Java to Kotlin is like going from a unicycle to a spaceship! So much less code and less hassle!

K 7

✌️ 2

orangy

05/01/2017, 6:11 PM

@mg6maciej a kotl.in/issue would be nice to have with all the information you have there

louiscad

05/01/2017, 8:56 PM

Hi, anyone knows how to make IntelliJ highlight the `TODO()`calls in blue like it does for

//TODO

comments?

groostav

05/02/2017, 5:37 AM

blegh, is there an equatable lazy in kotlin?

marcinmoskala

05/02/2017, 7:30 AM

Just released 🙂 Might be useful https://github.com/MarcinMoskala/KotlinDiscreteMathToolkit

mg6maciej

05/02/2017, 8:10 AM

Given this compiles:

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fun x(aFunc: A.(file: File) -> Unit) = Unit
x { it.blah() }

should also this compile?

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x(File::blah)

dimsuz

05/02/2017, 11:53 AM

Hi! I wonder if using kotlin delegates automatically means using reflection mechanisms. They have KProperty and all... Reflection brings performance costs on Android, that's why I am concerned about this.

zak.taccardi

05/02/2017, 3:55 PM

is there any way to quickly deconstruct a data class in IntelliJ?