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
Property Wrapperで遊ぼう / Play with Property Wrapper
Search
Yutaro Muta
September 11, 2019
Programming
2
300
Property Wrapperで遊ぼう / Play with Property Wrapper
帰ってきた関西モバイルアプリ研究会#3
https://kanmoba.connpass.com/event/137475/
Yutaro Muta
September 11, 2019
Tweet
Share
More Decks by Yutaro Muta
See All by Yutaro Muta
Swiftの “private” を テストする / Testing Swift "private"
yutailang0119
0
140
Apple Vision Pro購入RTA 1泊3日弾丸ハワイツアー / RTA: Purchase Apple Vision Pro in Hawaii
yutailang0119
0
1.4k
個人開発のたのしみ / Enjoying personal development
yutailang0119
0
900
バックポートして学ぶ新APIの仕組み
yutailang0119
0
2.6k
Backport AsyncImage
yutailang0119
0
660
xcrun Essentials
yutailang0119
6
1.2k
Let's Coding SwiftUI on iPad!
yutailang0119
1
480
Back of First Screen AB test of Hatena Bookmark iOS app with Firebase AB Testing
yutailang0119
0
290
Lab of WWDC19
yutailang0119
1
500
Other Decks in Programming
See All in Programming
バックエンドのためのアプリ内課金入門 (サブスク編)
qnighy
8
1.8k
Java Webフレームワークの現状 / java web framework at burikaigi
kishida
9
2.2k
Open source software: how to live long and go far
gaelvaroquaux
0
650
第3回 Snowflake 中部ユーザ会- dbt × Snowflake ハンズオン
hoto17296
4
380
クリーンアーキテクチャから見る依存の向きの大切さ
shimabox
4
880
バッチを作らなきゃとなったときに考えること
irof
1
410
Serverless Rust: Your Low-Risk Entry Point to Rust in Production (and the benefits are huge)
lmammino
1
140
『GO』アプリ バックエンドサーバのコスト削減
mot_techtalk
0
150
GAEログのコスト削減
mot_techtalk
0
120
Amazon Q Developer Proで効率化するAPI開発入門
seike460
PRO
0
120
Multi Step Form, Decentralized Autonomous Organization
pumpkiinbell
1
800
CI改善もDatadogとともに
taumu
0
170
Featured
See All Featured
Chrome DevTools: State of the Union 2024 - Debugging React & Beyond
addyosmani
4
350
Practical Orchestrator
shlominoach
186
10k
Designing on Purpose - Digital PM Summit 2013
jponch
117
7.1k
4 Signs Your Business is Dying
shpigford
182
22k
Unsuck your backbone
ammeep
669
57k
Building an army of robots
kneath
303
45k
10 Git Anti Patterns You Should be Aware of
lemiorhan
PRO
656
59k
Agile that works and the tools we love
rasmusluckow
328
21k
KATA
mclloyd
29
14k
Let's Do A Bunch of Simple Stuff to Make Websites Faster
chriscoyier
507
140k
We Have a Design System, Now What?
morganepeng
51
7.4k
ReactJS: Keep Simple. Everything can be a component!
pedronauck
666
120k
Transcript
Property WrapperͰ༡΅͏ 2019/09/11 @ؼ͖ͬͯͨؔϞόΠϧΞϓϦݚڀձ#3 Yutaro Muta @yutailang0119
• Yutaro Muta @yutailang0119 • Hatena Co., Ltd. @Kyoto •
Conference Staff • builderscon 2017, 2018, 2019 • try! Swift Tokyo 2019, 2020 • try! Swift Tokyo 2020 νέοτൢച։࢝ • https://www.tryswift.co/events/2020/tokyo/en/ Who am I ?
⚠͝ҙ • ڥ • macOS Mojave Version 10.14.6 • Xcode
11.0 GM seed (11M419c)
Property Wrapper
Property Wrapper • https://github.com/apple/swift-evolution/blob/master/proposals/0258-property- wrappers.md • ࠷ॳͷPitchProperty Delegateͱͯ͠ɺMarch 3, 2019ʹొ
• https://forums.swift.org/t/returned-for-revision-se-0258-property-delegates/24080 • Swift 5.1 ~ • ొॳSwift 5.1ʹೖΒͳ͍ͩΖ͏ͱ͍͏ҹ͕ͩͬͨɺWWDCͰApple͕ൃදͨ͠ SwiftUIʹ༻͞Ε͍ͯΔ • Swift 5.1ͷfinal branchingMarch 18, 2019
Property Wrapper • https://github.com/apple/swift-evolution/blob/master/proposals/0258-property- wrappers.md • ࠷ॳͷPitchProperty Delegateͱͯ͠ɺMarch 3, 2019ʹొ
• https://forums.swift.org/t/returned-for-revision-se-0258-property-delegates/24080 • Swift 5.1 ~ • ొॳSwift 5.1ʹೖΒͳ͍ͩΖ͏ͱ͍͏ҹ͕ͩͬͨɺWWDCͰApple͕ൃදͨ͠ SwiftUIʹ༻͞Ε͍ͯΔ • Swift 5.1ͷfinal branchingMarch 18, 2019
https://github.com/apple/swift-evolution/blob/master/ proposals/0258-property-wrappers.md https://github.com/apple/swift-evolution/blob/master/proposals/0258-property-wrappers.md
https://github.com/apple/swift-evolution/blob/master/ proposals/0258-property-wrappers.md https://github.com/apple/swift-evolution/blob/master/proposals/0258-property-wrappers.md
OSS SwiftͰ࣮த
࣮ঢ়گ • େͰ͖͍ͯΔ • https://github.com/apple/swift/pulls?utf8=✓&q=is%3Apr+SE-+0258 • όάใࠂ͔ͳΓ͋Δ • https://bugs.swift.org/issues/?jql=labels+%3D+PropertyWrappers
BugΛ୳ͦ͏
Property WrapperͷΑ͋͘Δྫ
Property Wrapper x UserDefaults
Property Wrapper x UserDefaults • [WWDC 2019] What's New in
Swift • https://developer.apple.com/videos/play/wwdc2019/402 • UserDefaultsΛWrapͯ͠ɺϘΠϥʔϓϨʔτΛ௵͍ͯ͘͠
@propertyWrapper struct UserDefault<T> { let key: String let defaultValue: T
init(_ key: String, defaultValue: T) { self.key = key self.defaultValue = defaultValue UserDefaults.standard.register(defaults: [key: defaultValue]) } var wrappedValue: T { get { return UserDefaults.standard.object(forKey: key) as? T ?? defaultValue } set { UserDefaults.standard.set(newValue, forKey: key) } } } Property Wrapper x UserDefaults
@UserDefault("USES_TOUCH_ID", defaultValue: false) static var usesTouchID: Bool @UserDefault("LOGGED_IN", defaultValue: false)
static var isLoggedIn: Bool if !isLoggedIn && usesTouchID { !authenticateWithTouchID() } Property Wrapper x UserDefaults
defaultValue == nil Ͱ͖ͦ͏ͩͳ
@propertyWrapper struct UserDefault<T> { let key: String let defaultValue: T
init(_ key: String, defaultValue: T) { self.key = key self.defaultValue = defaultValue } var wrappedValue: T { get { return UserDefaults.standard.object(forKey: key) as? T ?? defaultValue } set { UserDefaults.standard.set(newValue, forKey: key) } } } Property Wrapper x UserDefaults x Optional
@UserDefault("USES_TOUCH_ID", defaultValue: nil) static var usesTouchID: Bool @UserDefault("LOGGED_IN", defaultValue: false)
static var isLoggedIn: Bool if !isLoggedIn && usesTouchID { !authenticateWithTouchID() } Property Wrapper x UserDefaults x Optional
@UserDefault("USES_TOUCH_ID", defaultValue: nil) static var usesTouchID: Bool @UserDefault("LOGGED_IN", defaultValue: false)
static var isLoggedIn: Bool if !isLoggedIn && usesTouchID { !authenticateWithTouchID() } Property Wrapper x UserDefaults x Optional
None
@UserDefault("USES_TOUCH_ID", defaultValue: nil) static var usesTouchID: Bool print(type(of: usesTouchID)) //
Optional<Bool> ܕΛݟͯΈΔ
None
ͱ͍͏͜ͱͰ
https://bugs.swift.org/browse/SR-11443
SR-11443 Property Wrapper overwrites type declaration • bugs swiftʹग़ͨ͠
Simple Case import Foundation var value: Any = "value" @propertyWrapper
struct Wrapper<Value> { private let defaultValue: Value init(defaultValue: Value) { self.defaultValue = defaultValue } var wrappedValue: Value { get { (value as? Value) ?? defaultValue } set { value = newValue } } } final class Playground { @Wrapper(defaultValue: nil) var explicitlyOptional: String? @Wrapper(defaultValue: nil) var implicitlyOptional: String @Wrapper(defaultValue: "NonOptional") var nonOptional: String func printExplicitlyOptionalType() { print(type(of: self.explicitlyOptional)) } func printImplicitlyOptionalType() { print(type(of: self.implicitlyOptional)) } func printNonOptionalType() { print(type(of: self.nonOptional)) } } let playground = Playground() playground.printExplicitlyOptionalType() // Optional<String> playground.printImplicitlyOptionalType() // Optional<String> playground.printNonOptionalType() // String
·ͱΊ
·ͱΊ • Property WrapperΛ͍ͯ͠ɺόάใࠂΛ͍ͯ͜͠͏
&OKPZ1SPQFSUZ8SBQQFS 5IBOLT w NVUBZVUBSP!HNBJMDPN w IUUQTUXJUUFSDPNZVUBJMBOH w IUUQTHJUIVCDPNZVUBJMBOH