Kotlin JS: Is it a Thing?

Transcript

1. Kotlin/js
   IS IT A THING?
   Alexey Buzdin, MARCH 2017
   

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2. Me
   WRITING Mobile AND Java STUFF
   ORGANIZING events
   SPEAKING AT conferences
   TEACHING people
   

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3. Kotlin
   IS IT A THING?
   

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4. GREAT AT
   ANDROID!
   

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5. “She turned to the sunlight
   And shook her yellow head,
   And whispered to her neighbor:
   "Winter is dead.”
   - A.A. MILNE, When We Were Very Young
   https://spring.io/blog/2016/02/15/developing-spring-boot-applications-with-kotlin
   

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6. https://github.com/gradle/gradle-script-kotlin
   

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7. Kotlin/js
   

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8. INSTALL KOTLIN
   brew install kotlin
   

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9. Let’s create HelloKotlin.kt
   fun main(args: Array) {
   println("Hello JavaScript!")
   }
   

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10. Let’s create HelloKotlin.kt
    fun main(args: Array) {
    println("Hello JavaScript!")
    }
    Let’s compile it to javascript
    kotlinc-js -output out/sample-library.js -meta-info HelloKotlin.kt
    

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11. Let’s create HelloKotlin.kt
    fun main(args: Array) {
    println("Hello JavaScript!")
    }
    Let’s compile transpile it to javascript
    kotlinc-js -output out/sample-library.js -meta-info HelloKotlin.kt
    

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12. GENERATED CONTENT
    *.META.JS - METAINFORMATION FOR REFLECTION
    

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13. if (typeof kotlin === 'undefined') {
    throw new Error(“Error loading module …”);
    }
    this['sample-library'] = function (_, Kotlin) {
    'use strict';
    var println = Kotlin.kotlin.io.println_s8jyv4$;
    function main(args) {
    println('Hello JavaScript!');
    }
    _.main_kand9s$ = main;
    Kotlin.defineModule('sample-library', _);
    main([]);
    return _;
    }(typeof this['sample-library'] === 'undefined' ? {} :
    this['sample-library'], kotlin);
    

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14. 
    
    
    
    Console Output
    
    
    
    
    
    
    THE KOTLIN STANDARD LIBRARY IS ALSO ON NPM!
    

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15. HELP
    

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16. Running with GRADLE
    buildscript {
    ext.kotlin_version = '1.1.1'
    repositories { mavenCentral() }
    dependencies {
    classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    }
    }
    apply plugin: 'kotlin2js'
    repositories { mavenCentral() }
    dependencies {
    compile "org.jetbrains.kotlin:kotlin-stdlib-js:$kotlin_version"
    }
    

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17. ALL LANGUAGE FEATURES IN
    KOTLIN 1.1 WORKS IN
    JavaScript!
    

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18. ALL JS LIBRARIES ARE
    AVAILABLE IN KOTLIN!
    Use ts2kt to convert type definitions
    http://definitelytyped.org
    

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19. THANK YOU!
    Q&A
    Follow me on Twitter @ALEXEYBUZDIN
    

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