Kotlin Everywhere

Transcript

1. Kotlin everywhere

2. Who’s speaking Rob @ NYT Boris @ ClearScore 2

3. #CPIT2 sli.do Join the discussion

4. Where https://pusher.com/state-of-kotlin

5. Desktop apps with a little bit of Tornado™

6. • JavaFX • Beautiful DSL • UI + Background thread

   • Injection • REST • Field validation • Can work™ with JS TornadoFX 6

7. tornadofx.io goo.gl/qSjBPG goo.gl/gcrZss

8. iOS apps and Android (but we wanted the WOW moment)

9. Kotlin Native COMMON no platform specific dependencies class/function declaration 9

   PLATFORM implementations of platform-dependent declarations in the common module always an implementation of a single common module REGULAR targets specific platform can be dependency of platform modules can depend on platform modules

10. 10

11. ◇ common module defines expected declarations ◇ expected declarations never

    contain any implementation code 11 expected

12. 12 actual ◇ platform module provides actual declarations ◇ actual

    declarations must match expected declarations

13. 13 package org.jetbrains.foo expect class Foo(bar: String) { fun frob()

    } fun main(args: Array<String>) { Foo("Hello").frob() }

14. 14 package org.jetbrains.foo actual class Foo actual constructor(val bar: String)

    { actual fun frob() { println("Frobbing the $bar") } }

15. JVM Backend

16. 16

17. Javascript Both Frontend and Backend!

18. 18

19. 19

20. ◇ You can set and call everything you want on

    properties of this type ◇ Disables compiler checks (beware of runtime errors) 20 dynamic

21. ◇ Kotlin assumes the implementation is provided by the developer

    (in JS) ◇ The compiler will not generate JS code for this function ◇ No auto completion 21 external

22. 22 external fun require(module: String): dynamic fun main(args: Array<String>) {

    val app = require(“express”) app.get(“/hello”, {req, res -> res.send(“Hello world!”) }) }

23. } 23 { Kotlin wrappers

24. 24 @JsModule(“express”) external class Express { fun get( route: String,

    callback: (req: Request, res: Response) -> Unit ) external class Request external class Response { fun send(data: String) } }

25. } 25 { Kotlin wrappers https://github.com/JetBrains/kotlin-wrappers

26. Thanks! Any questions? You can find us at: ◇ @_tiwiz

    ◇ @borisdamato 26