What's up next for Kotlin?

Our community is officially one year old! What happened in the last years, where we started from, and what we managed to achieve.

We will start from the beginning to see how a simple idea shaped into a meetup for hundred of developers, providing content and opportunities to learn Kotlin together.

Not only our meetup grew a lot: after Google I/O 2017 Kotlin adoption skyrocketed. There's probably never been a better moment for the Kotlin ecosystem, and the language is getting ready to become The "write once, run everywhere" solution.

Let's walk through some of the features of the upcoming Kotlin release (1.3), to see what the Kotlin future might look like.

Transcript

1. What’s up next
   for Kotlin?
   Nicola Corti
   @cortinico
   

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2. HH
   

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3. A bit of history
   

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5. Speakers
   • Gesh Markov
   • Christophe Beyls
   • Niklas Baudy
   • Cord Jastram
   • Yahya Bayramoglu
   • Jossi Wolf
   • Jendrik Johannes
   • Ivan Morgillo
   • Jule Lehmann
   • Dmitry Zaytsev
   Lovis Möller - Nicola Corti
   

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7. Stats
   • 7 Meetups organized in the last year
   • ~280 total attendees
   • 333 Meetup Members
   • 128 Twitter Followers
   • Basically always booked out!
   

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9. pusher.com/state-of-kotlin
   

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10. Kotlin Adoption
    

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11. Migrating Java to Kotlin
    

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12. Reasons for
    returning to Java
    Over a quarter of
    respondents who
    migrated Java to Kotlin
    needed to revert.
    

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13. Favorite Features
    

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14. Reasons to use
    coroutines (or not)
    

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15. 1.3
    

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16. 1.3-M1 EAP
    

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17. 1.3-M1 EAP
    plugins {
    kotlin("jvm") version "1.2.60"
    }
    repositories {
    mavenCentral()
    }
    dependencies {
    compile(kotlin("stdlib-jdk8", "1.2.60"))
    }
    

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18. 1.3-M1 EAP
    plugins {
    kotlin("jvm") version "1.2.60"
    }
    repositories {
    mavenCentral()
    maven("http://dl.bintray.com/kotlin/kotlin-eap")
    }
    dependencies {
    compile(kotlin("stdlib-jdk8", "1.2.60"))
    }
    

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19. 1.3-M1 EAP
    plugins {
    kotlin("jvm") version "1.3-M1"
    }
    repositories {
    mavenCentral()
    maven("http://dl.bintray.com/kotlin/kotlin-eap")
    }
    dependencies {
    compile(kotlin("stdlib-jdk8", "1.3-M1"))
    }
    

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20. 1.3-M1 EAP
    plugins {
    kotlin("jvm") version "1.3-M1"
    }
    repositories {
    mavenCentral()
    maven("http://dl.bintray.com/kotlin/kotlin-eap")
    }
    dependencies {
    compile(kotlin("stdlib-jdk8", “1.3-M1"))
    compile(“org.jetbrains.kotlinx:kotlinx-coroutines-core:0.24.0")
    }
    

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21. 1.3-M1 EAP
    plugins {
    kotlin("jvm") version "1.3-M1"
    }
    repositories {
    mavenCentral()
    maven("http://dl.bintray.com/kotlin/kotlin-eap")
    }
    dependencies {
    compile(kotlin("stdlib-jdk8", “1.3-M1"))
    compile(“org.jetbrains.kotlinx:kotlinx-coroutines-core:0.24.0-eap13")
    }
    

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22. Coroutines
    

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23. Coroutines
    kotlin {
    experimental.coroutines = Coroutines.ENABLE
    }
    

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24. Coroutines
    import kotlinx.coroutines.experimental.delay
    import kotlinx.coroutines.experimental.launch
    fun justACoroutine() {
    launch {
    delay(1000)
    println("Hello world!")
    }
    }
    

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25. Coroutines
    import kotlinx.coroutines.delay
    import kotlinx.coroutines.launch
    fun justACoroutine() {
    launch {
    delay(1000)
    println("Hello world!")
    }
    }
    

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26. Capturing When
    

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27. Capturing When
    fun Request.getBody() : ResponseBody {
    val response = executeRequest()
    when (response) {
    is Authenticator.Success -> response.body
    is HttpError -> throw HttpException(response.status)
    }
    }
    

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28. Capturing When
    fun Request.getBody() : ResponseBody {
    when (val response = executeRequest()) {
    is Authenticator.Success -> response.body
    is HttpError -> throw HttpException(response.status)
    }
    }
    

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29. Capturing When
    fun Request.getBody() =
    when (val response = executeRequest()) {
    is Authenticator.Success -> response.body
    is HttpError -> throw HttpException(response.status)
    }
    

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30. Capturing When
    

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31. Interfaces
    interface MyPublicApi {
    }
    

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32. Interfaces
    interface MyPublicApi {
    companion object {
    val baseUrl = "http://..."
    fun create(): MyPublicApi = ...
    }
    }
    

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33. Interfaces
    interface MyPublicApi {
    companion object {
    @JvmField
    val baseUrl = "http://..."
    @JvmStatic
    fun create(): MyPublicApi = ...
    }
    }
    Java 1.8
    

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34. Annotations
    annotation class MyAnnotation(val value: Int)
    

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35. Annotations
    annotation class MyAnnotation(val value: Int) {
    annotation class SubAnnotation
    }
    

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36. Annotations
    annotation class MyAnnotation(val value: Int) {
    annotation class SubAnnotation
    companion object {
    val timestamp = System.currentTimeMillis()
    }
    }
    

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37. Annotations
    annotation class MyAnnotation(val value: Int) {
    annotation class SubAnnotation
    companion object {
    @JvmField
    val timestamp = System.currentTimeMillis()
    }
    }
    

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38. KEEP
    

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39. KEEP
    

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40. Arity
    

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41. Arity
    fun arity22Function(lambda : (
    Int, Int, Int, Int, Int, Int, Int, Int, Int, Int,
    Int, Int, Int, Int, Int, Int, Int, Int, Int, Int,
    Int, Int) -> Unit) {
    }
    

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42. Arity
    fun arity22Function(lambda : (
    Int, Int, Int, Int, Int, Int, Int, Int, Int, Int,
    Int, Int, Int, Int, Int, Int, Int, Int, Int, Int,
    Int, Int) -> Unit) {
    }
    public final void arity22Function(@NotNull Function22 lambda) {
    Intrinsics.checkParameterIsNotNull(lambda, "lambda");
    }
    

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43. Arity
    package kotlin.jvm.functions
    /** A function that takes 0 arguments. */
    public interface Function0 : Function {
    /** Invokes the function. */
    public operator fun invoke(): R
    }
    /** A function that takes 1 argument. */
    public interface Function1 : Function {
    /** Invokes the function with the specified argument. */
    public operator fun invoke(p1: P1): R
    }
    /** A function that takes 2 arguments. */
    public interface Function2 : Function {
    /** Invokes the function with the specified arguments. */
    public operator fun invoke(p1: P1, p2: P2): R
    }
    /** A function that takes 3 arguments. */
    public interface Function3 : Function {
    /** Invokes the function with the specified arguments. */
    public operator fun invoke(p1: P1, p2: P2, p3: P3): R
    }
    /** A function that takes 4 arguments. */
    public interface Function4 : Function {
    /** Invokes the function with the specified arguments. */
    public operator fun invoke(p1: P1, p2: P2, p3: P3, p4: P4): R
    }
    /** A function that takes 5 arguments. */
    public interface Function5 : Function {
    /** Invokes the function with the specified arguments. */
    public operator fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5): R
    }
    /** A function that takes 6 arguments. */
    public interface Function6 : Function {
    /** Invokes the function with the specified arguments. */
    public operator fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6): R
    }
    /** A function that takes 7 arguments. */
    public interface Function7 : Function {
    /** Invokes the function with the specified arguments. */
    public operator fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7): R
    }
    /** A function that takes 8 arguments. */
    public interface Function8 : Function {
    /** Invokes the function with the specified arguments. */
    public operator fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8): R
    }
    /** A function that takes 9 arguments. */
    public interface Function9 : Function {
    /** Invokes the function with the specified arguments. */
    public operator fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9): R
    }
    /** A function that takes 10 arguments. */
    public interface Function10 : Function {
    /** Invokes the function with the specified arguments. */
    public operator fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10): R
    }
    /** A function that takes 11 arguments. */
    public interface Function11 : Function {
    

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44. Arity
    /** A function that takes 8 arguments. */
    public interface Function8 : Function {
    /** Invokes the function with the specified arguments. */
    public operator fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8): R
    }
    /** A function that takes 9 arguments. */
    public interface Function9 : Function {
    /** Invokes the function with the specified arguments. */
    public operator fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9): R
    }
    /** A function that takes 10 arguments. */
    public interface Function10 : Function {
    /** Invokes the function with the specified arguments. */
    public operator fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10): R
    }
    /** A function that takes 11 arguments. */
    public interface Function11 : Function {
    /** Invokes the function with the specified arguments. */
    public operator fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11): R
    }
    /** A function that takes 12 arguments. */
    public interface Function12 : Function {
    /** Invokes the function with the specified arguments. */
    public operator fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12): R
    }
    /** A function that takes 13 arguments. */
    public interface Function13 : Function {
    /** Invokes the function with the specified arguments. */
    public operator fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13): R
    }
    /** A function that takes 14 arguments. */
    public interface Function14 : Function {
    /** Invokes the function with the specified arguments. */
    public operator fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14): R
    }
    /** A function that takes 15 arguments. */
    public interface Function15 : Function {
    /** Invokes the function with the specified arguments. */
    public operator fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15): R
    }
    /** A function that takes 16 arguments. */
    public interface Function16 : Function {
    /** Invokes the function with the specified arguments. */
    public operator fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16): R
    }
    /** A function that takes 17 arguments. */
    public interface Function17 : Function {
    /** Invokes the function with the specified arguments. */
    public operator fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17): R
    }
    /** A function that takes 18 arguments. */
    public interface Function18 : Function {
    /** Invokes the function with the specified arguments. */
    public operator fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17, p18: P18): R
    }
    /** A function that takes 19 arguments. */
    public interface Function19 : Function {
    /** Invokes the function with the specified arguments. */
    public operator fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17, p18: P18, p19: P19): R
    }
    /** A function that takes 20 arguments. */
    public interface Function20 : Function {
    /** Invokes the function with the specified arguments. */
    public operator fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17, p18: P18, p19: P19, p20: P20): R
    }
    /** A function that takes 21 arguments. */
    public interface Function21 : Function {
    /** Invokes the function with the specified arguments. */
    public operator fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17, p18: P18, p19: P19, p20: P20, p21: P21): R
    }
    /** A function that takes 22 arguments. */
    public interface Function22 : Function {
    /** Invokes the function with the specified arguments. */
    public operator fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17, p18: P18, p19: P19, p20: P20, p21: P21, p22: P22): R
    }
    

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45. Arity
    fun arity22Function(lambda : (
    Int, Int, Int, Int, Int, Int, Int, Int, Int, Int,
    Int, Int, Int, Int, Int, Int, Int, Int, Int, Int,
    Int, Int) -> Unit) {
    }
    

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46. Arity
    fun arity23Function(lambda : (
    Int, Int, Int, Int, Int, Int, Int, Int, Int, Int,
    Int, Int, Int, Int, Int, Int, Int, Int, Int, Int,
    Int, Int, Int) -> Unit) {
    }
    

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47. Arity
    fun arity23Function(lambda : (
    Int, Int, Int, Int, Int, Int, Int, Int, Int, Int,
    Int, Int, Int, Int, Int, Int, Int, Int, Int, Int,
    Int, Int, Int) -> Unit) {
    }
    public final void arity23Function(@NotNull FunctionN lambda) {
    Intrinsics.checkParameterIsNotNull(lambda, "lambda");
    }
    

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48. Arity
    fun arity23Function(lambda : (
    Int, Int, Int, Int, Int, Int, Int, Int, Int, Int,
    Int, Int, Int, Int, Int, Int, Int, Int, Int, Int,
    Int, Int, Int) -> Unit) {
    }
    public final void arity23Function(@NotNull FunctionN lambda) {
    Intrinsics.checkParameterIsNotNull(lambda, "lambda");
    }
    

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49. Arity
    @SinceKotlin("1.3")
    interface FunctionN : Function, FunctionBase {
    /**
    * Invokes the function with the specified arguments.
    *
    * Must **throw exception** if the length of passed [args]
    * is not equal to the parameter count returned by [arity].
    *
    * @param args arguments to the function
    */
    operator fun invoke(vararg args: Any?): R
    /**
    * Returns the number of arguments that must be passed to
    * this function.
    */
    override val arity: Int
    }
    http://bit.ly/keep-bigarity
    

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50. Experimental features
    

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51. Inline Classes
    

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52. Inline Classes
    inline class Username(val value: String)
    

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53. Inline Classes
    inline class Username(val value: String)
    typealias Username = String
    

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54. Inline Classes
    inline class Username(val value: String)
    inline class Password(val value: String)
    

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55. Inline Classes
    inline class Username(val value: String)
    inline class Password(val value: String)
    val myName = Username("nicola")
    val myPassword = Password("p4ssw0rd")
    

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56. Inline Classes
    inline class Username(val value: String)
    inline class Password(val value: String)
    val myName = Username("nicola")
    val myPassword = Password("p4ssw0rd")
    myName = myPassword
    

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57. Inline Classes
    inline class Username(val value: String)
    inline class Password(val value: String)
    val myName = Username("nicola")
    val myPassword = Password("p4ssw0rd")
    myName = myPassword
    myPassword = myName
    

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58. Inline Classes
    inline class Username(val value: String)
    inline class Password(val value: String)
    val myName = Username("nicola")
    val myPassword = Password("p4ssw0rd")
    myName = myPassword
    myPassword = myName
    myName = "MyNewName"
    bit.ly/keep-inlineclasses
    

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59. Unsigned Types
    

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60. Unsigned Types
    val anUnsignedInteger : UInt
    val anUnsignedLong : ULong
    val anUnsignedByte : UByte
    val anUnsignedShort : UShort
    

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61. Unsigned Types
    val anUnsignedInteger : UInt = 0xFFFF_FFFFu
    val anUnsignedLong : ULong = 10uL
    val anUnsignedByte : UByte = 0xFFu
    val anUnsignedShort : UShort = 0xFFFFu
    

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62. Unsigned Types
    @SinceKotlin("1.3")
    @ExperimentalUnsignedTypes
    public inline class UInt internal constructor(private val data: Int) :
    Comparable {
    bit.ly/keep-utype
    

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63. Experimental Annotations
    

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64. Experimental Annotations
    @Experimental(Experimental.Level.WARNING)
    annotation class MyCoolFeatureExperimental
    

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65. Experimental Annotations
    @Experimental(Experimental.Level.WARNING)
    annotation class MyCoolFeatureExperimental
    @MyCoolFeatureExperimental
    fun myExperimentalFunction() {
    // ...
    }
    

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66. Experimental Annotations
    @Experimental(Experimental.Level.WARNING)
    annotation class MyCoolFeatureExperimental
    @MyCoolFeatureExperimental
    fun myExperimentalFunction() {
    // ...
    }
    @UseExperimental(MyCoolFeatureExperimental::class)
    fun myClientCode() {
    myExperimentalFunction()
    }
    

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67. Experimental Annotations
    @Experimental(Experimental.Level.WARNING)
    annotation class MyCoolFeatureExperimental
    @MyCoolFeatureExperimental
    fun myExperimentalFunction() {
    // ...
    }
    @UseExperimental(MyCoolFeatureExperimental::class)
    fun myClientCode() {
    myExperimentalFunction()
    }
    bit.ly/keep-experimental
    

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68. SuccessOrFailure
    

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69. SuccessOrFailure
    /**
    * A discriminated union that encapsulates successful outcome
    * with a value of type [T] or a failure with an arbitrary
    * [Throwable] exception.
    */
    inline class SuccessOrFailure internal constructor(
    internal val value: Any? // internal value -- either T or Failure
    ) {
    internal class Failure(val exception: Throwable)
    //...
    }
    

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70. SuccessOrFailure
    /**
    * A discriminated union that encapsulates successful outcome
    * with a value of type [T] or a failure with an arbitrary
    * [Throwable] exception.
    */
    inline class SuccessOrFailure internal constructor(
    internal val value: Any? // internal value -- either T or Failure
    ) {
    internal class Failure(val exception: Throwable)
    //...
    }
    

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71. SuccessOrFailure
    /**
    * A discriminated union that encapsulates successful outcome
    * with a value of type [T] or a failure with an arbitrary
    * [Throwable] exception.
    */
    inline class SuccessOrFailure internal constructor(
    internal val value: Any? // internal value -- either T or Failure
    ) {
    internal class Failure(val exception: Throwable)
    //...
    }
    

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72. SuccessOrFailure
    /**
    * A discriminated union that encapsulates successful outcome
    * with a value of type [T] or a failure with an arbitrary
    * [Throwable] exception.
    */
    inline class SuccessOrFailure internal constructor(
    internal val value: Any? // internal value -- either T or Failure
    ) {
    internal class Failure(val exception: Throwable)
    //...
    }
    inline fun runCatching(block: () -> R): SuccessOrFailure
    

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73. SuccessOrFailure
    /**
    * A discriminated union that encapsulates successful outcome
    * with a value of type [T] or a failure with an arbitrary
    * [Throwable] exception.
    */
    inline class SuccessOrFailure internal constructor(
    internal val value: Any? // internal value -- either T or Failure
    ) {
    internal class Failure(val exception: Throwable)
    //...
    }
    inline fun runCatching(block: () -> R): SuccessOrFailure
    

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74. SuccessOrFailure
    inline fun runCatching(block: () -> R): SuccessOrFailure {
    return try {
    SuccessOrFailure.success(block())
    } catch (e: Throwable) {
    SuccessOrFailure.failure(e)
    }
    }
    

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75. SuccessOrFailure
    fun findUserByName(name: String): ?
    

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76. SuccessOrFailure
    fun findUserByName(name: String): SuccessOrFailure
    You can do better…
    

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77. SuccessOrFailure
    fun findUserByName(name: String): User
    

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78. SuccessOrFailure
    sealed class FindUserResult {
    data class Found(val user: User) : FindUserResult()
    data class NotFound(val name: String) : FindUserResult()
    data class MalformedName(val name: String) : FindUserResult()
    // other cases that need different business-specific handling code
    }
    fun findUserByName(name: String): FindUserResult
    

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79. SuccessOrFailure
    fun findUserByName(name: String): User
    

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80. SuccessOrFailure
    fun findUserByName(name: String): User
    val result = runCatching { findUserByName("...") }
    

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81. SuccessOrFailure
    fun findUserByName(name: String): User
    fun findUserByNameCatching(name: String): SuccessOrFailure
    val result = runCatching { findUserByName("...") }
    

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82. SuccessOrFailure - Use Cases
    

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83. SuccessOrFailure - Use Cases
    fun readFilesCatching(files: List): List> =
    files.map {
    }
    

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84. SuccessOrFailure - Use Cases
    fun readFilesCatching(files: List): List> =
    files.map {
    runCatching {
    readFile(it)
    }
    }
    

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85. SuccessOrFailure - Use Cases
    fun readFilesCatching(files: List): List> =
    files.map {
    runCatching {
    readFile(it)
    }
    }
    readFilesCatching(listOf("...")).map {
    }
    

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86. SuccessOrFailure - Use Cases
    fun readFilesCatching(files: List): List> =
    files.map {
    runCatching {
    readFile(it)
    }
    }
    readFilesCatching(listOf("...")).map { result ->
    }
    

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87. SuccessOrFailure - Use Cases
    fun readFilesCatching(files: List): List> =
    files.map {
    runCatching {
    readFile(it)
    }
    }
    readFilesCatching(listOf("...")).map { result : SuccessOrFailure ->
    }
    

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88. SuccessOrFailure - Use Cases
    fun readFilesCatching(files: List): List> =
    files.map {
    runCatching {
    readFile(it)
    }
    }
    readFilesCatching(listOf("...")).map { result ->
    result.mapCatching {
    formatFile(it)
    }
    }
    

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89. SuccessOrFailure - Use Cases
    fun readFilesCatching(files: List): List> =
    files.map {
    runCatching {
    readFile(it)
    }
    }
    readFilesCatching(listOf("...")).map { result ->
    result.mapCatching {
    formatFile(it)
    }
    }
    

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90. SuccessOrFailure - Use Cases
    

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91. SuccessOrFailure - Use Cases
    try {
    val data = doSomething()
    processData(data)
    } catch(e: Throwable) {
    showErrorDialog(e)
    }
    

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92. SuccessOrFailure - Use Cases
    try {
    val data = doSomething()
    processData(data)
    } catch(e: Throwable) {
    showErrorDialog(e)
    }
    runCatching { doSomething() }
    .onFailure { showErrorDialog(it) }
    .onSuccess { processData(it) }
    

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93. SuccessOrFailure - Use Cases
    

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94. SuccessOrFailure - Use Cases
    /**
    * Interface representing a continuation after a suspension point that
    * returns value of type `T`.
    */
    @SinceKotlin("1.3")
    public interface Continuation {
    /**
    * Context of the coroutine that corresponds to this continuation.
    */
    public val context: CoroutineContext
    /**
    * Resumes the execution of the corresponding coroutine passing successful or failed
    [result] as the
    * return value of the last suspension point.
    */
    public fun resumeWith(result: SuccessOrFailure)
    }
    bit.ly/keep-successorfailure
    

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95. To infinity…
    • Collections Literals
    • SAM Conversion
    • Truly Immutability
    val list = listOf("1", "2", "3")
    val list = ["1", "2", "3"]
    val map = mapOf("1" to 1, "2" to 2, "3" to 3)
    val map = ["1" = 1, "2" = 2, "3" = 3]
    interface Function {
    fun run(data: T)
    }
    val myFunction: Function =
    { println ("data $it”) }
    class Foo(var v: Int)
    immutable class Bar(val foo: Foo)
    // This should fail
    bit.ly/kotlin-feature-survey
    

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96. Thanks!
    Nicola Corti
    @cortinico
    

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