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
Simplifying State by partially introducing unid...
Search
Benedikt Terhechte
October 13, 2017
Programming
3
870
Simplifying State by partially introducing unidirectional data flow in your codebase
Benedikt Terhechte
October 13, 2017
Tweet
Share
More Decks by Benedikt Terhechte
See All by Benedikt Terhechte
NSSpain 2023: An overview of different approaches to share code across platforms
terhechte
0
400
SwiftUI & UIKit, a match made in heaven or match made in hell?
terhechte
0
59
Learnings from building Design Systems at XING
terhechte
1
470
Introduction to Swift Keypaths
terhechte
15
20k
Sharing Code between iOS and Android with Rust
terhechte
8
2.3k
Protocols with Associated Types: When to use them and how to avoid their pitfalls
terhechte
2
260
Swift on the Server
terhechte
2
300
Macoun 2016 - Swift auf dem Server
terhechte
3
260
NSSpain 2016: Developing App-Backends with Swift on the Server
terhechte
2
23k
Other Decks in Programming
See All in Programming
Datadog Workflow Automation で圧倒的価値提供
showwin
1
160
機能が複雑化しても 頼りになる FactoryBotの話
tamikof
0
130
プログラミング言語学習のススメ / why-do-i-learn-programming-language
yashi8484
0
160
Rails 1.0 のコードで学ぶ find_by* と method_missing の仕組み / Learn how find_by_* and method_missing work in Rails 1.0 code
maimux2x
1
190
Go 1.24でジェネリックになった型エイリアスの紹介
syumai
2
280
Django NinjaによるAPI開発の効率化とリプレースの実践
kashewnuts
1
250
第3回関東Kaggler会_AtCoderはKaggleの役に立つ
chettub
3
1.2k
負債になりにくいCSSをデザイナとつくるには?
fsubal
10
2.6k
color-scheme: light dark; を完全に理解する
uhyo
7
490
Open source software: how to live long and go far
gaelvaroquaux
0
660
Unity Android XR入門
sakutama_11
0
180
2025.2.14_Developers Summit 2025_登壇資料
0101unite
0
190
Featured
See All Featured
For a Future-Friendly Web
brad_frost
176
9.6k
The Web Performance Landscape in 2024 [PerfNow 2024]
tammyeverts
4
430
Building Your Own Lightsaber
phodgson
104
6.2k
No one is an island. Learnings from fostering a developers community.
thoeni
21
3.1k
Dealing with People You Can't Stand - Big Design 2015
cassininazir
366
25k
A better future with KSS
kneath
238
17k
How STYLIGHT went responsive
nonsquared
98
5.4k
Refactoring Trust on Your Teams (GOTO; Chicago 2020)
rmw
33
2.8k
Done Done
chrislema
182
16k
Rebuilding a faster, lazier Slack
samanthasiow
80
8.9k
Chrome DevTools: State of the Union 2024 - Debugging React & Beyond
addyosmani
4
370
4 Signs Your Business is Dying
shpigford
182
22k
Transcript
1
2
3
4
5
6
7
8
9
None
10
11
12
13
14
None
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
/// Model struct Cinnamon { let value: Int = 0
} enum Event { case increase } 45
/// Model struct Cinnamon { let value: Int = 0
} enum Event { case increase } func reducer(state: Cinnamon, event: Event) -> Cinnamon { var newState = state if event == .increase { newState.value += 1 } return newState } /// UI let builder = Form(state: Cinnamon(), reducer: reducer) 46
47
48
49
struct AddressBook { var contacts: [Person] var searchTerm: String var
scrollPosition: Int } 50
struct AddressBookApp { struct Data { var contacts: [Person] }
var data: Data struct UI { var searchTerm: String var scrollPosition: Int } var ui: UI } 51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
private var subscribers: [String: (State)->Void] = [:] public func subscribe(_
subscriber: @escaping (State)->Void) -> String { let token = UUID().uuidString subscribers[token] = subscriber subscriber(state) return token } 66
67
protocol FormComponent { associatedtype State func setup(with state: State) func
update(state: State) -> Void } public func subscribe<Component: FormComponent> (_ subscriber: Component) -> String where Component.State == State {... 68
69
func subscribe<Type: Equatable>( path: KeyPath<Data, Type>, action: @escaping (_ oldValue:
Type, _ newValue: Type) -> Void ) -> String struct Person { let name: String } form.subscribe(path: \Person.name) { (old, new) in ... } 70
private var history: [State] = [] func apply(_ change: (inout
State) -> Void) { states.append(state) change(&state) notifySubscribers() } func undo() { state = history.popLast() notifySubscribers() } 71
72
73
74
75
76
77
78
79
80