Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
Scala 3 - A Quick Tour - Scala Italy 2021
Search
Daniela Sfregola
October 23, 2021
Programming
0
200
Scala 3 - A Quick Tour - Scala Italy 2021
Daniela Sfregola
October 23, 2021
Tweet
Share
More Decks by Daniela Sfregola
See All by Daniela Sfregola
Scala 3 - A Quick Tour - Singapore Scala Programmers 2021
danielasfregola
1
110
ScalaBase 2021- FP: the Good, the Bad, the Ugly
danielasfregola
0
170
Top 5 Cool Things about Scala 3 (that are not enums)
danielasfregola
0
210
LSUG 2019 - FP: The Good, The Bad and The Ugly
danielasfregola
2
260
Scala IO 2019 - FP: The Good, The Bad and The Ugly
danielasfregola
1
820
Scala Days 2019 - Refactor all the things!
danielasfregola
0
280
Refactor all the things!
danielasfregola
0
470
Scala Italy 2018 - Random Data Generation with ScalaCheck
danielasfregola
0
1.7k
Scala Days 2018 Berlin - A Pragmatic Introduction to Category Theory
danielasfregola
2
1.3k
Other Decks in Programming
See All in Programming
どの様にAIエージェントと 協業すべきだったのか?
takefumiyoshii
2
600
あなたの知らない「動画広告」の世界 - iOSDC Japan 2025
ukitaka
0
380
CSC509 Lecture 01
javiergs
PRO
1
430
CSC509 Lecture 03
javiergs
PRO
0
330
Serena MCPのすすめ
wadakatu
4
900
CSC305 Lecture 03
javiergs
PRO
0
230
プロダクト開発をAI 1stに変革する〜SaaS is dead時代で生き残るために〜 / AI 1st Product Development
kobakei
0
490
なぜあの開発者はDevRelに伴走し続けるのか / Why Does That Developer Keep Running Alongside DevRel?
nrslib
3
370
ネイティブ製ガントチャートUIを作って学ぶUICollectionViewLayoutの威力
jrsaruo
0
130
育てるアーキテクチャ:戦い抜くPythonマイクロサービスの設計と進化戦略
fujidomoe
1
150
2025年版 サーバーレス Web アプリケーションの作り方
hayatow
23
25k
Чего вы не знали о строках в Python – Василий Рябов, PythoNN
sobolevn
0
160
Featured
See All Featured
Fashionably flexible responsive web design (full day workshop)
malarkey
407
66k
RailsConf 2023
tenderlove
30
1.2k
Writing Fast Ruby
sferik
629
62k
Improving Core Web Vitals using Speculation Rules API
sergeychernyshev
19
1.2k
実際に使うSQLの書き方 徹底解説 / pgcon21j-tutorial
soudai
PRO
188
55k
The Art of Delivering Value - GDevCon NA Keynote
reverentgeek
15
1.7k
Chrome DevTools: State of the Union 2024 - Debugging React & Beyond
addyosmani
7
890
Save Time (by Creating Custom Rails Generators)
garrettdimon
PRO
32
1.6k
Creating an realtime collaboration tool: Agile Flush - .NET Oxford
marcduiker
32
2.2k
A better future with KSS
kneath
239
17k
Git: the NoSQL Database
bkeepers
PRO
431
66k
Measuring & Analyzing Core Web Vitals
bluesmoon
9
610
Transcript
Scala 3 A Quick Tour @DanielaSfregola Scala Italy - October
2021
Hellooooo • Software Engineer living in London UK •
Scala Lover ❤ • OS Maintainer • Author of "Get Programming with Scala" by Manning 35% OFF on EVERYTHING with code "ctwscalait21"
Scala 3 is here! • After 8 years of work
• 28,000 commits • 7,400 pull requests • 4,100 closed issues • ...released on May 13th, 2021! https://www.scala-lang.org/blog/2021/05/14/scala3-is-here.html
An overview • https://dotty.ep fl .ch/docs/reference/overview.html
@main Annotation object HelloWorld extends App { println("Hello World!" )
}
@main Annotation object HelloWorld extends App { println("Hello World!" )
} object HelloWorld { @main def hello: Unit = { println("Hello world!" ) } }
@main Annotation object HelloWorld extends App { println("Hello World!" )
} object HelloWorld { @main def hello: Unit = { println("Hello world!" ) } } object Hello { @main def echo(n: Int, word: String): Unit = { println(word * n ) } }
Parametrized Traits trait Nameable { def name: Strin g }
Parametrized Traits trait Nameable { def name: Strin g }
trait Nameable(name: String)
Intersection Types class A class B def foo: A &
B = ???
Union Types class A class B def foo: A |
B = ???
Package Object // in file my/demo/package.scal a package m y
package object demo { def customLog(msg: String) { println(s"Customised package log: $msg" ) } }
Package Object // in file my/demo/package.scal a package m y
package object demo { def customLog(msg: String) { println(s"Customised package log: $msg" ) } } [ DROPPED ]
Enums sealed abstract class Color(val rgb: Int) case object Red
extends Color(0xFF0000 ) case object Green extends Color(0x00FF00 ) case object Blue extends Color(0x0000FF)
Enums sealed abstract class Color(val rgb: Int) case object Red
extends Color(0xFF0000 ) case object Green extends Color(0x00FF00 ) case object Blue extends Color(0x0000FF) enum Color(val rgb: Int) : case Red extends Color(0xFF0000 ) case Green extends Color(0x00FF00 ) case Blue extends Color(0x0000FF)
Improved Type Inference Map("Scala" -> 3).map { (k, v) =>
s"$k$v" }
Improved Type Inference Map("Scala" -> 3).map { (k, v) =>
s"$k$v" } Scala 2.13.4
Improved Type Inference Map("Scala" -> 3).map { (k, v) =>
s"$k$v" } Scala 2.13.4
Improved Type Inference Map("Scala" -> 3).map { (k, v) =>
s"$k$v" } Scala 3.0.0
Improved Type Inference Map("Scala" -> 3).map { (k, v) =>
s"$k$v" } Scala 3.0.0 Scala 2.13.4
Procedure Syntax def echo(str: String) { st r }
Procedure Syntax def echo(str: String) { st r } Scala
2.13.4
Procedure Syntax def echo(str: String) { st r } Scala
2.13.4
Procedure Syntax def echo(str: String) { st r } Scala
3
Procedure Syntax def echo(str: String) { st r } Scala
3
Improved Error Messages Arrested Developers What the Scala Compiler &
Lucille Bluth Have In Common by Fiona Condon, NeScala 2017 https://www.youtube.com/watch?v=78iIbiRwFTM
Improved Error Messages def echo(str: String): Unit = { st
r } def echoTwice(str: String): String = { echo(str) match { case x: String => s"$x$x " } }
Improved Error Messages Scala 2.13.4
Improved Error Messages Scala 2.13.4 Scala 3
Strict Equality List("Scala", "3").headOption == "Scala"
Strict Equality List("Scala", "3").headOption == "Scala" Scala 2.13.4
Strict Equality List("Scala", "3").headOption == "Scala" Scala 2.13.4 Scala 3
Compatibility with 2.13 Migrating to Scala 3 is easy* !
* if you are using Scala 2.13 * if you don't have macros in your code Scala 3 Migration Guide https://docs.scala-lang.org/scala3/guides/migration
Thank You! •Twitter: @DanielaSfregola •"Get Programming with Scala" by
Manning 35% OFF on EVERYTHING with code "ctwscalait21"