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  • r

    robin

    01/23/2019, 8:40 AM
    So, has there been any discussion around Kotlin Quines yet? Here's a one-liner I built, but there might be shorter solutions:
    Copy code
    fun main(){val f="""fun main(){val f="%s"%s"%s";System.out.printf(f,'"',f,'"')}""";System.out.printf(f,'"',f,'"')}
    👍 1
  • d

    Dalinar

    01/23/2019, 9:05 AM
    what does the 
    ::
    prefix do in 
    ::x.isInitialized
    ?
  • d

    diesieben07

    01/23/2019, 9:05 AM
    It creates a 
    KProperty
    for 
    x
    .
  • d

    diesieben07

    01/23/2019, 9:06 AM
  • d

    domfox

    11/18/2019, 12:20 PM
    Resolution to this was to exclude 
    kotlin-stdlib
    from the 
    mapdb
    dependency, as this depends on 1.2.x which confuses things. Paying attention to compiler warnings pays off!
  • a

    Ashutosh Panda

    11/19/2019, 4:48 PM
    Copy code
    error: a type annotation is required on a value parameter
fun roll(number,operation:(Int)->Int):Int
         ^
  • a

    Ashutosh Panda

    11/19/2019, 4:49 PM
    The below is the error
  • a

    Ashutosh Panda

    11/19/2019, 4:49 PM
    can anyone please tell where is the error
  • e

    evan

    11/19/2019, 9:02 PM
  • b

    Ben Piatt

    11/19/2019, 9:23 PM
    It works fine for simple types like Int or String, but I'm talking about types that accept generics, so for example Column<Int>? where the column itself can be null, but I'm giving you a Column<Int>
  • s

    Samuel Michael

    11/20/2019, 3:22 AM
    any channel for discussion of tensor flow/ml in kotlin?
  • n

    nwh

    11/20/2019, 3:22 AM
    #ai
    🧵 2
  • p

    Pablichjenkov

    11/20/2019, 5:32 PM
    Copy code
    class CustomLayout : RelativeLayout {

    
    constructor(context: Context) : super(context)
    
    constructor(context: Context, attrs: AttributeSet) : super(context, attrs)
    
    constructor(context: Context, attrs: AttributeSet, defStyleAttr: Int) : super(
        context,
        attrs,
        defStyleAttr
    )

    private var mGlucoseState = GlucoseState.NONE
...

    override fun onCreateDrawableState(extraSpace: Int): IntArray {
        
        val drawableState = super.onCreateDrawableState(extraSpace + 7)

        when (mGlucoseState) { // Crashing because mGlucoseState is null

            GlucoseState.LOW -> View.mergeDrawableStates(
                drawableState,
                STATE_GLUCOSE_LOW
            )

            GlucoseState.DANGER_LOW -> View.mergeDrawableStates(
                drawableState,
                STATE_GLUCOSE_WARN_LOW
            )

            ... 

            else -> View.mergeDrawableStates(
                drawableState,
                STATE_GLUCOSE_NONE
            )

        }

        return drawableState
    }

...

}
  • p

    Pablichjenkov

    11/20/2019, 5:34 PM
    I am having a weird behaviour with above class. It is a custom Android FrameLayout. The function 
    onCreateDrawableState()
    is called internally from the constructor and the process crashes with 
    mGlucoseState
    null. How is that possible?
  • m

    Marko Mitic

    11/20/2019, 5:36 PM
    move it above constructor
  • p

    Pablichjenkov

    11/20/2019, 5:46 PM
    Moving it above did not work.
  • s

    Shawn

    11/20/2019, 5:51 PM
    I think I’ve seen this before - I think 
    this
    is being sort of leaked by the superclass constructor calling 
    onCreateDrawableState()
  • m

    Marko Mitic

    11/20/2019, 5:51 PM
    Ah, yes, android super constructors calling overriden methods. https://kotlinlang.org/docs/reference/classes.html#derived-class-initialization-order warns about this
  • p

    Pablichjenkov

    11/20/2019, 5:58 PM
    Very interesting! I got away now by making it 
    nullable?
    but I think is a good catch up that should have IDE warning the least. Thank u guys.
  • u

    user

    11/21/2019, 1:25 PM
    https://twitter.com/kotlin/status/1197506273652011008 Mobile developers, we value your opinions! We’d like to have a better understanding of your needs, so we’re asking you take this short survey. If you work as an Android or iOS developer, you could really help us out! https://t.co/CbKOHLtK8g Twitter
  • h

    Hullaballoonatic

    11/21/2019, 6:03 PM
    Is there a stdlib function that creates a map from two collections (one keys, one values)? The following code accomplishes this, but creates an extra interim list of pairs
    Copy code
    a.zip(b).toMap()
    I accomplished this in my particular use-case involving enums, but that's because I have access to the ordinal
    Copy code
    MyEnumClass.values().associate { it to myList[it.ordinal] }
  • j

    John

    11/21/2019, 10:11 PM
    Or if anyone has any impression, it is mine that building APIs and backend services is probably where it’s most used for currently
  • m

    Michał Kalinowski

    11/21/2019, 11:44 PM
    Hey, so I would like make kotlin/java bindings and I would use JNI(kotlin-native is too unstable for now) for making C Api, but I'm not sure how slow are such bindings. I know that call C from Java is relatively fast in JNI. But I'm not sure how fast is from C to Java. Maybe someone have own experience and can share about how it looks like?
  • u

    user

    11/22/2019, 10:01 AM
    https://twitter.com/kotlin/status/1197817240277536769 Kotlin supports nested comments. You don't need to use workarounds like // ... // #KotlinTips

    https://pbs.twimg.com/media/EJ-AbczUUAIM_Of.png▾

    Twitter
  • y

    Yekta

    11/22/2019, 12:10 PM
    Copy code
    return if (arrayList!![position] is Array<Line>)
                RowType.LINE.ordinal
        else
            0
    Android Studio gives me error: Cannot check for instance of erased type: Array<Line>
  • y

    Yekta

    11/22/2019, 12:11 PM
    arrayList is ArrayList of Any type
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