Kotlin 2021 Recap / DevFest 2021

Resouces

- Mascot
https://blog.jetbrains.com/kotlin/2021/10/introducing-the-kotlin-mascot/

- Kotlin 1.5.x
https://kotlinlang.org/docs/whatsnew15.html
https://kotlinlang.org/docs/whatsnew1520.html
https://kotlinlang.org/docs/whatsnew1530.html

- Kotlin 1.6
https://kotlinlang.org/docs/whatsnew16.html

- Coroutines
https://blog.jetbrains.com/kotlin/2021/05/kotlin-coroutines-1-5-0-released/
https://github.com/Kotlin/kotlinx.coroutines/releases/tag/1.6.0-RC
https://github.com/Kotlin/kotlinx.coroutines/releases/tag/1.6.0-RC2

- Kotlin Symbol Processing
https://github.com/google/ksp

- Multiple platform
https://blog.jetbrains.com/kotlin/2021/10/compose-multiplatform-goes-beta/
https://blog.jetbrains.com/kotlin/2021/10/kmm-beta-roadmap-video-highlights/

- K2 Compiler
https://www.youtube.com/watch?v=iTdJJq_LyoY
https://www.youtube.com/watch?v=db19VFLZqJM

Transcript

1. Kotlin 2021 Recap Kenji Abe (@STAR_ZERO) Android, Kotlin GDE / DeNA Co., Ltd. [Tokyo]
4. Kotlin 1.5
5. value class UserId(val id: Int) val userId = UserId(1)
6. // State.kt sealed interface State // Success.kt data class Success(val data: Data): State // Failure.kt data class Failure(val e: Exception): State
7. val uint: UInt = 1u val ulong: ULong = 2u val ushort: UShort = 3u val ubyte: UByte = 4u
8. val value = "..." value.toUpperCase() value.uppercase() value.toLowerCase() value.lowercase() value.capitalize() value.replaceFirstChar { it.uppercase() } value.decapitalize() value.replaceFirstChar { it.lowercase() }
9. Coroutines 1.5
11. val channel = Channel<String>(...) channel.offer("...") // true or false or throw Exception channel.trySend("...") // ChannelResult channel.poll() // get or null channel.tryReceive() // ChannelResult
12. Kotlin Symbol Processing
13. Kotlin Symbol Processing 1. Kotlinの軽量コンパイラプラグイン開発ツール 2. KAPTのような機能 3. KAPTより高速 4. Kotlinのコードを直接解析 5. Multiple Platformのサポート
14. Multiplatform
15. Multiplatform 1. Compose multiplatform 1.0 2. KMM Beta (2022春予定) 3. New Kotlin/Native memory management
16. Kotlin 1.6
17. class Func : suspend (String) -> Result { override suspend fun invoke(s: String): Result { // ... } } val func: suspend (String) -> Result = Func() val result = func("test")
18. annotation class Marker(val value: String) val marker = Marker("Sample")
20. // build.gradle kotlin { sourceSets.all { languageSettings { progressiveMode = true } } }
22. val sec = 10000.seconds println(sec.inWholeHours) // 2 println(sec.inWholeMinutes) // 166 val duration = sec + 10.hours duration.toComponents { d, h, m, s, ns -> println("${d}d ${h}h ${m}m ${s}s") // => 0d 12h 46m 40s }
23. val list = buildList { add("a") if (condition) { add("b") } add("c") } val map = buildMap { put("a", 1) } val set = buildSet { add("a") }
24. Coroutines 1.6
25. Coroutines 1.6 1. kotlinx-coroutines-test に様々な変更 2. CoroutineDispatcher.limitedParallelism の導入 3. Kotlin/Native new memory model をサポート
26. K2 Compiler
27. *.kt Frontend Native Backend LLVM bitcode generator IR JS Backend JVM Backend IR Generator *.so *.js *.class Syntax tree + Semantic info Before
28. *.kt Frontend Native Backend LLVM bitcode generator IR JS IR Backend JavaScript generator IR JVM IR Backend JVM bytecode generator IR IR Generator *.so *.js *.class Syntax tree + Semantic info Now
29. *.kt New Frontend Native Backend LLVM bitcode generator IR JS IR Backend JavaScript generator IR JVM IR Backend JVM bytecode generator IR IR Generator *.so *.js *.class FIR Goal
30. Resources • Mascot ◦ https://blog.jetbrains.com/kotlin/2021/10/introducing-the-k otlin-mascot/ • Kotlin 1.5.x ◦ https://kotlinlang.org/docs/whatsnew15.html ◦ https://kotlinlang.org/docs/whatsnew1520.html ◦ https://kotlinlang.org/docs/whatsnew1530.html • Kotlin 1.6 ◦ https://kotlinlang.org/docs/whatsnew16.html
31. Resources • Coroutines ◦ https://blog.jetbrains.com/kotlin/2021/05/kotlin-coroutines -1-5-0-released/ ◦ https://github.com/Kotlin/kotlinx.coroutines/releases/tag/1 .6.0-RC ◦ https://github.com/Kotlin/kotlinx.coroutines/releases/tag/1 .6.0-RC2 • Kotlin Symbol Processing ◦ https://github.com/google/ksp
32. Resources • Multiple platform ◦ https://blog.jetbrains.com/kotlin/2021/10/compose-multiplat form-goes-beta/ ◦ https://blog.jetbrains.com/kotlin/2021/10/kmm-beta-roadmap- video-highlights/ • K2 Compiler ◦ https://www.youtube.com/watch?v=iTdJJq_LyoY ◦ https://www.youtube.com/watch?v=db19VFLZqJM
33. STAR_ZERO STAR-ZERO Thank you [Tokyo]