kotlin-test-junit is not using junit 5?

e.g. Having a class which represents a list, (but doesn't implement list), and allowing the methods defined for lists to be usable on it?

you think we’ll ever get runnable Kotlin scratch files?

Kotlin Team works on feature called Contracts, that will allow such smart cast

something like that?

require(geometry is LineString) { "Wrong geometry type in string" }
val line = geometry as LineString
return line

also you can use something like:

fun String.toGeoLineString(): LineString {
   val geometry = readGeometryFromString(this)
   return requireNotNull(geometry as? LineString)
}

Is it possible to develop for IOS with kotlin? Which IDE does Kotlin support for iOS?

Is it not possible to use a class' non-static function as a first class function?

Hi, why calling

thenApply

like this is possible

CompletableFuture.completedFuture("x").thenApply { it }

but second version with executor

CompletableFuture.completedFuture("x").thenApply({ it }, Executors.newCachedThreadPool())

throws compilation error and I have to do something like this

CompletableFuture.completedFuture("x").thenApply(java.util.Function<String, String> { it }, Executors.newCachedThreadPool())

Any suggestions for where one could locate Kotlin jobs or job listings?

.partition { ... }.let { (first, second) -> first + second }

should work?

and that

in

keyword can be used in a

when

for any

operator fun contains

, whether it's defined as

String.contains

,

List.contains

, your own custom type's

contains

function, etc

hi guys, yesterday i was asked an interesting question: how to deal with multiple optional values. should we go for simple null checks via if, or can we do it via a more sophisticated approach using something like let. given the following in an external module (to make it even harder to disable smart casting):

data class Person(
        val name: String?,
        val age: Int?
)
fun moduleExternal() = Person("", 1)

and a target function with a signature of:

fun safeCall(x1: String, x2: Int) {}

the following WON'T compile due to not being able to smart cast external module's properties:

fun solution_no_smartcasts() {
    val person = moduleExternal()
    if (person.name != null && person.age != null) {
        safeCall(person.name, person.age) // ERROR!
    }
}

in order to get rid of the smart cast problem first, i came up with the following idea of destructuring:

fun solution_destructure() {
    val (name, age) = moduleExternal()
    if (name != null && age != null) {
        safeCall(name, age)
    }
}

ok, but how about that "low level" if? apple's swift would solve it this way:

if let name = person.name as? String, let age = person.age as? Int {
    // name and age are non-optional in here
}

so i thought about an extended if which "kind of" solves it:

fun <T1, T2> ifNotNull(x1: T1?, x2: T2?, action: (T1, T2) -> Unit) {
    if (x1 != null && x2 != null) {
        action(x1, x2)
    }
}

fun solution_kotlin_lets() {
    val person = moduleExternal()
    ifNotNull(person.name, person.age) { name, age ->
        safeCall(name, age)
    }
}

what are your thoughts on this topic?

@oleksiyp We just started to use Mockk in one of our modules to test it. API is really good, but I see problem that I don’t see stacktrace of undesirable call of some method on verify fail. Should I create feature request?

Hi, just wanted to quickly ask if anyone here uses Hawk https://github.com/orhanobut/hawk for encrypting user credentials, or if I should use another library or just do it manually with key store.

Where did you get the

scrollWindow

value from? @elect

Could someone explain why

org.jetbrains.kotlin:kotlin-stdlib-jre8

has use for AutoCloseable, but

org.jetbrains.kotlin:kotlin-stdlib-jdk8

doesn't?

Is there any particular reason there is no

toMap()

function available as an extension on a collection of

Map.Entry<K, V>

?

if you have a

List<Int>

and you just want the unique values, use

.toSet()

since sets don’t allow duplicate values

i try to build "kotlin-web-demo" but get a lot if errors like "com.intellij.lang.java not found" on the current master. i am new to java / kotlin but shouldn't "./gradlew build" just works?

i'm probably doing something very dumb here (trying to match a literal dollar followed by chars in a string)...

println("Hello \$name".contains(Regex("[a-zA-Z0-9]+"))) // true
println("Hello \$name".contains(Regex("\$[a-zA-Z0-9]+"))) // false

have to escape the dollar in the string literal or Kotlin will treat it as a reference and have to escape the dollar in the pattern or that means end of string

Is kotlinlang.org's CSS not loading for you guys too?

Now that I think about it, top level function should make more sense when you do pure FP in Kotlin

Hi, I have some question about

io.ktor.client.HttpClient

and how to handle different return codes 400. Having trouble finding documentation and good examples. Just starting out whit kotlin as well.

message has been deleted

How would the build cache work in practise over multiple machines?

I have a

data class

that has a parameter

metadata: List<Item>

, and I'm creating it from a nullable with:

metadata?.map { Item(it.key, it.value) } ?: listOf()

. Which is compiling fine, but when metadata is null I'm getting:

java.lang.IllegalArgumentException: Parameter specified as non-null is null: method kotlin.jvm.internal.Intrinsics.checkParameterIsNotNull