Thanks (I should have specified I meant the code in the

coroutines-guide.md

)

A property containing it's own name:

object Name {
    operator fun provideDelegate(thisRef: Any?, property: KProperty<*>) = property.name
}

operator fun String.getValue(thisRef: Any?, property: KProperty<*>) = this

val foo by Name

fun main(args: Array<String>) {
    println(foo) //prints "foo"
}

Hey guys, how can I call a function extension that is declared in another class?

When deciding on which one of overloaded functions are invoked, why isn't nullability considered?

fun func(a: Any?) {}

fun <T> func(a: Collection<T>) {}

fun main(args: Array<String>) {
	func(null) // Type inference fails here
}

@Paul Woitaschek in a case like this:

override fun post(req: Request, res: Response): Any {
        val platform = req.bodyAsObject() as Platform
        if (platform.isValid()) {
            PlatformRepository().save(platform)
            return object { val message = "Platform created" ; val status = 201 }
        } else {
            return renderInvalidParams()
        }
    }

I could avoid doing the

if else

statement by using functions as callback... just like this:

override fun post(req: Request, res: Response): Any {
        req.bodyAsObject(success = {
            PlatformRepository().save(platform)
            return object { val message = "Platform created" ; val status = 201 }
        }, failure = {
            return renderInvalidParams()
        })
    }

apply plugin: 'kotlin'
apply plugin: 'application'
apply plugin: 'org.junit.platform.gradle.plugin'

buildscript {
    ext.kotlin_version = '1.0.6'

    repositories {
        mavenCentral()
    }

    dependencies {
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
        classpath 'org.junit.platform:junit-platform-gradle-plugin:1.0.0-M3'
    }
}
---snip---

FAILURE: Build failed with an exception.

* Where:
Build file '/home/xolan/work/accounter/build.gradle' line: 1

* What went wrong:
A problem occurred evaluating root project 'accounter'.
> Failed to apply plugin [id 'kotlin']
   > For input string: ""

Any suggestions? Can't seem to figure this one out

@jjnguy My bad 😅

@mg6maciej Thanks for confirming it. I had reasons for overloading my function but will try the other route to workaround the problem.

I think we mark params, no? Can't check now, but may be incompatible annotations?

@Eugenio You could try changing language inspection settings. Also, why not use

reminderSubscription?.unsubscribe()

instead?

So you don't have a noop. This is basically the same as doing:

val unwrapped = optional
if(unwrapped != null) { doSmth() }
else { doSmthElse() }

Well, if your system architecture is that broken that you're getting unexpected side effects all over the place... Let me just say, the stricter type system is only going to help you there. As I said I don't know how it works in swift, but if you have a val that the compiler has inferred to not be null, that val will not be null, period. No way that could change.

since they dont seem to be bulletproof in swift

would Kotlin help me besides optionals and monkey patching utils

then when i open a kotlin file in my project (i am using gralde btw) it forces me to put this in my gradle file which is still 1.0.6

repositories {
    mavenCentral()
}

dependencies {
    compile "org.jetbrains.kotlin:kotlin-stdlib-jre8:$kotlin_version"
}

Isn’t it a memory leak with OOM?

@jjnguy I get the NPE when the function is called. It never actually executes the code. The only way I found is to write implementation in java and use that.

@somoni You could use a when statement, I don’t know that it’s actually O(1) but it’s definitely no worse than an if/else chain. ie.

val obj: Any = "asdf"
    when(obj) {
        is Int -> println("Int!")
        is Double -> println("Double!")
        is String -> { println("String!") } // you can add braces if you have a longer statement
    }

does anybody know whats causing this? It happens when I try to build with intelliJ:

Error: Kotlin: Multiple values are not allowed for plugin option org.jetbrains.kotlin.kapt:outputPlugin

@groostav are you using an RC build?

Lua has the nifty feature that

map["hello"]

can be written as

map.hello

(as long as the key is a valid identifier). That's Lua's way to compensate for not having classes with properties. The

by map

property delegate in Kotlin does something similar, but requires to explicitly list all the properties. Any chance that Kotlin would be able to do the same?

yeah @nkiesel, I think the suspected use case for

val x by map

was that it would primarily operate on objects of disparate types (a le Javascript), thus I think the

by map

idea was largely aimed as a shim for dynamic languages into kotlin. But I could agree with your assestment, especially when we have access to raw types. Perhaps it would be better if we had something like

val map: Map<String, Any?> = ...
val name:String by map //compiler error: cannot use `Map<String, Any?> as delegate for `val name: String` expected Value type to be String but was Any?

val name: String by (map as Map) //compiler warning: unchecked raw type cast: Map<String, Any?> to Map
val name: String by @SuppressWarnings("unchecked")(map as Map) //compiles without issue

unfortunately its a moot point since any change would break backwards compatibility in a pretty big way

Hey guys, there is an alternative or a better solution than slf4j library?

Any ideas?

What's the differences between me using lateinit var and by lazy, for stuff that gets init'd after create (), like Android, games etc

Can someone point me to a design document or discussion, why kotlin decided against statics?

i don't suppose there's a way to say

when (foo) { != 0 -> stuff(); else -> blah() }

, while still using the var specifier, aka the

(foo)

Has anyone seen a problem with 1.1RC whereby the stdlib isn't on the classpath when trying to start a simple spring boot app from the IDE? I get an error saying it can't find the kotlin.jvm.internal.Intrinsics class

Does Gson work well with Kotlin data classes?