Slide 1
Slide 1 text
async/awaitactorͰ
iOSΞϓϦ։ൃ͕Ͳ͏มΘΔ͔
Before & A)erͷ۩ମྫͰֶͿ
Yuta Koshizawa @koher
Slide 2
Slide 2 text
Swi$ 5.5
Slide 3
Slide 3 text
Concurrency
ʢฒߦॲཧʣ
Slide 4
Slide 4 text
iOS ΞϓϦ։ൃΛܶతʹม͑Δ
Slide 5
Slide 5 text
Proposal: 12 ຊ
WWDC: 9 ຊ
Slide 6
Slide 6 text
۩ମతͳࣄྫ
↓
நతͳ֓೦
Slide 7
Slide 7 text
iOS ΞϓϦ։ൃͱ͍͏۩ମྫ
Slide 8
Slide 8 text
Before & A)er ͷ۩ମྫͰֶͿ
Slide 9
Slide 9 text
21 ݸͷέʔε
Slide 10
Slide 10 text
Concurrency
!
async / await
!
Structured Concurrency
!
actor
Slide 11
Slide 11 text
!
async / await
Slide 12
Slide 12 text
Case 1: ඇಉظؔͷར༻
ΤϥʔϋϯυϦϯά͕ͳ͍߹
Slide 13
Slide 13 text
Before
func downloadData(from url: URL,
completion: @escaping (Data) -> Void)
Slide 14
Slide 14 text
Before
func downloadData(from url: URL,
completion: @escaping (Data) -> Void)
downloadData(from: url) { data in
// data Λ͏ॲཧ
}
Slide 15
Slide 15 text
async / await0296
0296 h'ps:/
/github.com/apple/swi9-evolu
Slide 16
Slide 16 text
Before
func downloadData(from url: URL,
completion: @escaping (Data) -> Void)
downloadData(from: url) { data in
// data Λ͏ॲཧ
}
Slide 17
Slide 17 text
A"er
func downloadData(from url: URL) async -> Data
let data = await downloadData(from: url)
// data Λ͏ॲཧ
Slide 18
Slide 18 text
A ͱ B ͕ಉ͡εϨουͰ࣮ߦ͞ΕΔͱݶΒͳ͍
func downloadData(from url: URL) async -> Data
print("A")
let data = await downloadData(from: url)
print("B")
Slide 19
Slide 19 text
A ͱ B ͕ಉ͡εϨουͰ࣮ߦ͞ΕΔͱݶΒͳ͍
func downloadData(from url: URL,
completion: @escaping (Data) -> Void)
print("A")
downloadData(from: url) { data in
print("B")
}
Slide 20
Slide 20 text
Case 3: ඇಉظؔͷར༻
ΤϥʔϋϯυϦϯά͕͋Δ߹
Slide 21
Slide 21 text
Case 1 (Before)
func downloadData(from url: URL, completion:
@escaping (Data) -> Void)
downloadData(from: url) { data in
// data Λ͏ॲཧ
}
Slide 22
Slide 22 text
Before
func downloadData(from url: URL, completion:
@escaping (Result) -> Void)
downloadData(from: url) { result in
do {
let data = try result.get()
// data Λ͏ॲཧ
} catch {
// ΤϥʔϋϯυϦϯά
}
}
Slide 23
Slide 23 text
A"er
func downloadData(from url: URL) async throws -> Data
do {
let data = try await downloadData(from: url)
// data Λ͏ॲཧ
} catch {
// ΤϥʔϋϯυϦϯά
}
Slide 24
Slide 24 text
Case 4: ඇಉظؔͷ࣮
ΤϥʔϋϯυϦϯά͕͋Δ߹
Slide 25
Slide 25 text
ྫ: User Λද͢ JSON Λऔಘͯ͠σίʔυ
Slide 26
Slide 26 text
Before
func fetchUser(for id: User.ID, completion: @escaping (Result) -> Void) {
let url: URL = .init(string: "https://koherent.org/fake-service/api/user?id=\(id)")!
}
Slide 27
Slide 27 text
Before
func fetchUser(for id: User.ID, completion: @escaping (Result) -> Void) {
let url: URL = .init(string: "https://koherent.org/fake-service/api/user?id=\(id)")!
downloadData(from: url) { result in
}
}
Slide 28
Slide 28 text
Before
func fetchUser(for id: User.ID, completion: @escaping (Result) -> Void) {
let url: URL = .init(string: "https://koherent.org/fake-service/api/user?id=\(id)")!
downloadData(from: url) { result in
let data = try result.get()
let user = try JSONDecoder().decode(User.self, from: data)
completion(.success(user))
}
}
Slide 29
Slide 29 text
Before
func fetchUser(for id: User.ID, completion: @escaping (Result) -> Void) {
let url: URL = .init(string: "https://koherent.org/fake-service/api/user?id=\(id)")!
downloadData(from: url) { result in
do {
let data = try result.get()
let user = try JSONDecoder().decode(User.self, from: data)
completion(.success(user))
} catch {
completion(.failure(error))
}
}
}
Slide 30
Slide 30 text
Before
func fetchUser(for id: User.ID, completion: @escaping (Result) -> Void) {
let url: URL = .init(string: "https://koherent.org/fake-service/api/user?id=\(id)")!
downloadData(from: url) { result in
do {
let data = try result.get()
let user = try JSONDecoder().decode(User.self, from: data)
completion(.success(user))
} catch {
completion(.failure(error))
}
}
}
Slide 31
Slide 31 text
A"er
func fetchUser(for id: User.ID) async throws -> User {
let url: URL = .init(string: "https://koherent.org/fake-service/api/user?id=\(id)")!
let data = try await downloadData(from: url)
let user = try JSONDecoder().decode(User.self, from: data)
return user
}
Slide 32
Slide 32 text
Case 5: ඇಉظؔͷ࿈݁
Slide 33
Slide 33 text
ྫ: ϢʔβʔΞΠίϯͷμϯϩʔυ
ʢͨͩ͠ɺΞΠίϯͷ URL Ϣʔβʔͷ JSON ͷதʹهࡌʣ
Slide 34
Slide 34 text
Ϣʔβʔͷ JSON ͷμϯϩʔυ
↓
ΞΠίϯͷμϯϩʔυ
Slide 35
Slide 35 text
Before
func fetchUserIcon(for id: User.ID,
completion: @escaping (Result) -> Void) {
let url: URL = .init(string: "https://koherent.org/fake-service/api/user?id=\(id)")!
downloadData(from: url) { data in
do {
let data = try data.get()
let user = try JSONDecoder().decode(User.self, from: data)
downloadData(from: user.iconURL) { icon in
do {
let icon = try icon.get()
completion(.success(icon))
} catch { completion(.failure(error)) }
}
} catch {
completion(.failure(error))
}
}
}
Slide 36
Slide 36 text
A"er
func fetchUserIcon(for id: User.ID) async throws -> Data {
let url: URL = .init(string: "https://koherent.org/fake-service/api/user?id=\(id)")!
let data = try await downloadData(from: url)
let user = try JSONDecoder().decode(User.self, from: data)
let icon = try await downloadData(from: user.iconURL)
return icon
}
Slide 37
Slide 37 text
Case 6: ίʔϧόοΫ͔Β
async ͷม
Slide 38
Slide 38 text
// ίʔϧόοΫ
func downloadData(from url: URL,
completion: @escaping (Result) -> Void)
// async
func downloadData(from url: URL) async throws -> Data {
}
Slide 39
Slide 39 text
// ίʔϧόοΫ
func downloadData(from url: URL,
completion: @escaping (Result) -> Void)
// async
func downloadData(from url: URL) async throws -> Data {
downloadData(from: url) { result in
do {
let data = try result.get()
} catch {
}
}
}
Slide 40
Slide 40 text
Con$nua$onSE-0300
SE-0300 h(ps:/
/github.com/apple/swi:-evolu
Slide 41
Slide 41 text
// ίʔϧόοΫ
func downloadData(from url: URL,
completion: @escaping (Result) -> Void)
// async
func downloadData(from url: URL) async throws -> Data {
downloadData(from: url) { result in
do {
let data = try result.get()
} catch {
}
}
}
Slide 42
Slide 42 text
// ίʔϧόοΫ
func downloadData(from url: URL,
completion: @escaping (Result) -> Void)
// async
func downloadData(from url: URL) async throws -> Data {
try await withCheckedThrowingContinuation { continuation in
downloadData(from: url) { result in
do {
let data = try result.get()
continuation.resume(returning: data)
} catch {
continuation.resume(throwing: error)
}
}
}
}
Slide 43
Slide 43 text
// ίʔϧόοΫ
func downloadData(from url: URL,
completion: @escaping (Result) -> Void)
// async
func downloadData(from url: URL) async throws -> Data {
try await withCheckedThrowingContinuation { continuation in
downloadData(from: url) { result in
do {
let data = try result.get()
continuation.resume(returning: data)
} catch {
continuation.resume(throwing: error)
}
}
}
}
Slide 44
Slide 44 text
// ίʔϧόοΫ
func downloadData(from url: URL,
completion: @escaping (Result) -> Void)
// async
func downloadData(from url: URL) async throws -> Data {
try await withCheckedThrowingContinuation { continuation in
downloadData(from: url) { result in
continuation.resume(with: result)
}
}
}
Slide 45
Slide 45 text
!
Structured Concurrency
Slide 46
Slide 46 text
Case 7: ඇಉظॲཧͷ։࢝
Slide 47
Slide 47 text
async ؔ async ؔͷதͰ͔͠ݺͳ͍
func foo() async { ... }
func bar() async {
await foo() //
✅
}
Slide 48
Slide 48 text
async ؔ async ؔͷதͰ͔͠ݺͳ͍
func foo() async { ... }
func bar() {
await foo() //
⛔
}
Slide 49
Slide 49 text
async ؔ async ؔͷதͰ͔͠ݺͳ͍
func foo() async { ... }
func bar() async {
await foo()
}
func baz() async {
await bar()
}
...
Slide 50
Slide 50 text
ඇಉظॲཧͷ։࢝
func main() {
// ???
}
Slide 51
Slide 51 text
ඇಉظॲཧͷ։࢝
func main() {
Task {
await foo()
}
}
Slide 52
Slide 52 text
ඇಉظॲཧͷ։࢝
func main() {
Task(operation: {
await foo()
})
}
Slide 53
Slide 53 text
ඇಉظॲཧͷ։࢝
func main() {
Task {
await foo()
}
}
ͯ͢ͷ async ؔ Task ্Ͱ࣮ߦ͞ΕΔɻ
Slide 54
Slide 54 text
iOS ΞϓϦ։ൃͰͲͷΑ͏ʹΘΕΔ͔
• viewDidAppear
• View Controller ͕දࣔ͞ΕͨΒ fetchUser Ͱ User Λऔಘ
ͯ͠දࣔ
• @IBAction
• μϯϩʔυϘλϯ͕ԡ͞ΕͨΒ downloadData Ͱμϯ
ϩʔυ
• ...
Slide 55
Slide 55 text
A"er
extension UserViewController {
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
ɹ
}
}
Slide 56
Slide 56 text
A"er
extension UserViewController {
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
do {
let user = try await fetchUser(for: userID)
self.user = user
} catch {
// ΤϥʔϋϯυϦϯά
}
}
}
Slide 57
Slide 57 text
A"er
extension UserViewController {
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
Task {
do {
let user = try await fetchUser(for: userID)
self.user = user
} catch {
// ΤϥʔϋϯυϦϯά
}
}
}
}
Slide 58
Slide 58 text
Case 9: ฒߦॲཧ
ݻఆݸͷ߹
Slide 59
Slide 59 text
ྫ: େখͷΞΠίϯΛಉ࣌ʹμϯϩʔυ
Slide 60
Slide 60 text
No content
Slide 61
Slide 61 text
A"er
func fetchUserIcons(for id: User.ID) async throws -> (small: Data, large: Data) {
let smallURL: URL = ...
let largeURL: URL = ...
return icons
}
Slide 62
Slide 62 text
͜ΕͰฒߦʹͳΒͳ͍
func fetchUserIcons(for id: User.ID) async throws -> (small: Data, large: Data) {
let smallURL: URL = ...
let largeURL: URL = ...
let smallIcon = try await downloadData(from: smallURL)
let largeIcon = try await downloadData(from: largeURL)
let icons = (small: smallIcon, large: largeIcon)
return icons
}
Slide 63
Slide 63 text
async let BindingSE-0317
SE-0317 h*ps:/
/github.com/apple/swi<-evolu>on/blob/main/proposals/0317-async-let.md
Slide 64
Slide 64 text
͜ΕͰฒߦʹͳΒͳ͍
func fetchUserIcons(for id: User.ID) async throws -> (small: Data, large: Data) {
let smallURL: URL = ...
let largeURL: URL = ...
let smallIcon = try await downloadData(from: smallURL)
let largeIcon = try await downloadData(from: largeURL)
let icons = (small: smallIcon, large: largeIcon)
return icons
}
Slide 65
Slide 65 text
A"er
func fetchUserIcons(for id: User.ID) async throws -> (small: Data, large: Data) {
let smallURL: URL = ...
let largeURL: URL = ...
async let smallIcon = downloadData(from: smallURL)
async let largeIcon = downloadData(from: largeURL)
let icons = try await (small: smallIcon, large: largeIcon)
return icons
}
Slide 66
Slide 66 text
A"er
func fetchUserIcons(for id: User.ID) async throws -> (small: Data, large: Data) {
let smallURL: URL = ...
let largeURL: URL = ...
async let smallIcon = downloadData(from: smallURL)
async let largeIcon = downloadData(from: largeURL)
let icons = try await (small: smallIcon, large: largeIcon)
return icons
}
async let ඞͣείʔϓͰ await ͞Εͳ͚ΕͳΒͳ͍ɻ
Slide 67
Slide 67 text
Structured ConcurrencySE-0304
SE-0304 h)ps:/
/github.com/apple/swi;-evolu=on/blob/main/proposals/0304-structured-concurrency.md
Slide 68
Slide 68 text
Structured Programming
ʢߏԽϓϩάϥϛϯάʣ
Slide 69
Slide 69 text
ߏԽϓϩάϥϛϯά
for value in values {
if value.isValid {
...
} else {
...
}
}
Slide 70
Slide 70 text
A"er
func fetchUserIcons(for id: User.ID) async throws -> (small: Data, large: Data) {
let smallURL: URL = ...
let largeURL: URL = ...
async let smallIcon = downloadData(from: smallURL)
async let largeIcon = downloadData(from: largeURL)
let icons = try await (small: smallIcon, large: largeIcon)
return icons
}
async let ඞͣείʔϓͰ await ͞Εͳ͚ΕͳΒͳ͍ɻ
Slide 71
Slide 71 text
async let ͱ Task
Task {
async let a = foo()
async let b = bar()
print(await a + b)
}
Slide 72
Slide 72 text
No content
Slide 73
Slide 73 text
No content
Slide 74
Slide 74 text
Case 11: ඇಉظॲཧͷΩϟϯηϧ
ඇಉظ API ͷར༻ଆ
Slide 75
Slide 75 text
Before
func downloadData(
from url: URL,
cancellation: @escaping () -> Void,
completion: @escaping (Result) -> Void
) -> DownloadCanceller
Slide 76
Slide 76 text
Before
extension ViewController {
@IBAction func downloadButtonPressed(_ sender: UIButton) {
ɹ
ɹ
ɹ
}
}
Slide 77
Slide 77 text
Before
extension ViewController {
@IBAction func downloadButtonPressed(_ sender: UIButton) {
canceller = downloadData(from: url, cancellation: {
// Ωϟϯηϧ࣌ͷॲཧ
}, completion: { data in
do {
let data = try data.get()
// data Λ͏ॲཧ
} catch {
// ΤϥʔϋϯυϦϯά
}
})
}
}
Slide 78
Slide 78 text
Before
extension ViewController {
@IBAction func cancelButtonPressed(_ sender: UIButton) {
canceller?.cancel()
canceller = nil
}
}
Slide 79
Slide 79 text
A"er
func downloadData(from url: URL) async throws -> Data
Slide 80
Slide 80 text
A"er
extension ViewController {
@IBAction func downloadButtonPressed(_ sender: UIButton) {
Task {
}
}
}
Slide 81
Slide 81 text
A"er
extension ViewController {
@IBAction func downloadButtonPressed(_ sender: UIButton) {
task = Task {
}
}
}
Slide 82
Slide 82 text
A"er
extension ViewController {
@IBAction func cancelButtonPressed(_ sender: UIButton) {
task?.cancel()
task = nil
}
}
Slide 83
Slide 83 text
No content
Slide 84
Slide 84 text
A"er
extension ViewController {
@IBAction func downloadButtonPressed(_ sender: UIButton) {
task = Task {
do {
let data = try await downloadData(from: url)
// data Λ͏ॲཧ
} catch {
if Task.isCancelled {
// Ωϟϯηϧ࣌ͷॲཧ
} else {
// ΤϥʔϋϯυϦϯά
}
}
}
}
}
Slide 85
Slide 85 text
!
actor
Slide 86
Slide 86 text
Case 14: ڞ༗͞Εͨঢ়ଶͷมߋ
Slide 87
Slide 87 text
ڞ༗͞Εͨঢ়ଶΛಉ࣌ʹಡΈॻ͖
↓
σʔλڝ߹
Slide 88
Slide 88 text
σʔλڝ߹ͷྫ
final class Counter {
private var count: Int = 0
func increment() -> Int {
count += 1
return count
}
}
Slide 89
Slide 89 text
σʔλڝ߹ͷྫ
let counter: Counter = .init()
DispatchQueue.global().async {
print(counter.increment()) // ?
}
DispatchQueue.global().async {
print(counter.increment()) // ?
}
Slide 90
Slide 90 text
σʔλڝ߹ͷྫ
let counter: Counter = .init()
DispatchQueue.global().async {
print(counter.increment()) // 1
}
DispatchQueue.global().async {
print(counter.increment()) // 2
}
Slide 91
Slide 91 text
σʔλڝ߹ͷྫ
let counter: Counter = .init()
DispatchQueue.global().async {
print(counter.increment()) // 2
}
DispatchQueue.global().async {
print(counter.increment()) // 1
}
Slide 92
Slide 92 text
σʔλڝ߹ͷྫ
let counter: Counter = .init()
DispatchQueue.global().async {
print(counter.increment()) // 2
}
DispatchQueue.global().async {
print(counter.increment()) // 2
}
Slide 93
Slide 93 text
σʔλڝ߹ͷྫ
final class Counter {
private var count: Int = 0
func increment() -> Int {
count += 1
return count
}
}
Slide 94
Slide 94 text
σʔλڝ߹Λ͙खஈ
• ϩοΫ
• γϦΞϧΩϡʔ
Slide 95
Slide 95 text
Before
final class Counter {
private let queue: DispatchQueue
= .init(label: UUID().uuidString)
private var count: Int = 0
func increment(completion: @escaping (Int) -> Void) {
queue.async { [self] in
count += 1
completion(count)
}
}
}
Slide 96
Slide 96 text
Before
let counter: Counter = .init()
counter.increment { count in
print(count) // 1 or 2
}
counter.increment { count in
print(count) // 2 or 1
}
Slide 97
Slide 97 text
actorSE-0306 Ͱղܾ
SE-0306 h)ps:/
/github.com/apple/swi;-evolu=on/blob/main/proposals/0306-actors.md
Slide 98
Slide 98 text
A"er
actor Counter {
private var count: Int = 0
func increment() -> Int {
count += 1
return count
}
}
Slide 99
Slide 99 text
σʔλڝ߹Λى͜͢ Counter
final class Counter {
private var count: Int = 0
func increment() -> Int {
count += 1
return count
}
}
Slide 100
Slide 100 text
A"er
actor Counter {
private var count: Int = 0
func increment() -> Int {
count += 1
return count
}
}
Slide 101
Slide 101 text
A"er
actor Counter {
private var count: Int = 0
func increment() async -> Int
}
Slide 102
Slide 102 text
A"er
let counter: Counter = .init()
Task.detached {
print(await counter.increment()) // 1 or 2
}
Task.detached {
print(await counter.increment()) // 2 or 1
}
Slide 103
Slide 103 text
Case 15: ڞ༗͞Εͨঢ়ଶͷมߋ
ΠϯελϯεͰͷϝιουݺͼग़͠
Slide 104
Slide 104 text
Counter ͷத͔Β Counter ͷϝιουΛ͏
final class Counter {
...
func increment(completion: @escaping (Int) -> Void)
func incrementTwice(completion: @escaping (Int) -> Void) {
}
}
Slide 105
Slide 105 text
Counter ͷத͔Β Counter ͷϝιουΛ͏
final class Counter {
...
func increment(completion: @escaping (Int) -> Void)
func incrementTwice(completion: @escaping (Int) -> Void) {
increment { [self] _ in
increment { count in
completion(count)
}
}
}
}
Slide 106
Slide 106 text
ڝ߹ঢ়ଶͷྫ
let counter: Counter = .init()
counter.incrementTwice { count in
print(count) // ?
}
counter.incrementTwice { count in
print(count) // ?
}
Slide 107
Slide 107 text
ڝ߹ঢ়ଶͷྫ
let counter: Counter = .init()
counter.incrementTwice { count in
print(count) // 2
}
counter.incrementTwice { count in
print(count) // 4
}
Slide 108
Slide 108 text
ڝ߹ঢ়ଶͷྫ
let counter: Counter = .init()
counter.incrementTwice { count in
print(count) // 3
}
counter.incrementTwice { count in
print(count) // 4
}
Slide 109
Slide 109 text
ڝ߹ঢ়ଶͷྫ
final class Counter {
...
func increment(completion: @escaping (Int) -> Void)
func incrementTwice(completion: @escaping (Int) -> Void) {
increment { [self] _ in
increment { count in
completion(count)
}
}
}
}
Slide 110
Slide 110 text
Before
final class Counter {
...
private func _increment() -> Int {
count += 1
return count
}
func increment(completion: @escaping (Int) -> Void) {
queue.async { [self] in
_increment()
completion(count)
}
}
...
}
Slide 111
Slide 111 text
Before
final class Counter {
...
func incrementTwice(completion: @escaping (Int) -> Void) {
queue.async { [self] in
_increment()
_increment()
completion(count)
}
}
}
Slide 112
Slide 112 text
A"er
actor Counter {
...
@discardableResult
func increment() -> Int {
count += 1
return count
}
func incrementTwice() -> Int {
increment()
increment()
return count
}
}
Slide 113
Slide 113 text
Case 16: ڞ༗͞Εͨঢ়ଶͷมߋ
ge#er
Slide 114
Slide 114 text
Case 14 (A*er)
actor Counter {
private var count: Int = 0
@discardableResult
func increment() -> Int {
count += 1
return count
}
}
Slide 115
Slide 115 text
A"er
actor Counter {
var count: Int = 0
@discardableResult
func increment() -> Int {
count += 1
return count
}
}
Slide 116
Slide 116 text
Effec%ul Read-only ϓϩύςΟSE-0310
class Foo {
var value : Int {
get {
...
}
}
}
SE-0310 h)ps:/
/github.com/apple/swi;-evolu=on/blob/main/proposals/0310-effecAul-readonly-proper=es.md
Slide 117
Slide 117 text
Effec%ul Read-only ϓϩύςΟSE-0310
class Foo {
var value : Int {
get async throws {
...
}
}
}
SE-0310 h)ps:/
/github.com/apple/swi;-evolu=on/blob/main/proposals/0310-effecAul-readonly-proper=es.md
Slide 118
Slide 118 text
A"er
actor Counter {
var count: Int {
get async { ... }
}
...
}
Slide 119
Slide 119 text
A"er
print(await counter.count)
Slide 120
Slide 120 text
Case 18: ڞ༗͞Εͨঢ়ଶͷมߋ
ඇಉظॲཧ݁Ռͷө
Slide 121
Slide 121 text
ObservableObject ͷಋೖ
final class UserViewController: UIViewController {
private let state: UserViewState
...
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
state.loadUser()
}
}
Slide 122
Slide 122 text
ObservableObject ͷಋೖ
final class UserViewController: UIViewController {
...
override func viewDidLoad() {
...
state
.objectWillChange
.receive(on: DispatchQueue.main)
.sink { [self] _ in
// state Λ View ʹө͢Δॲཧ
}
.store(in: &cancellables)
}
...
}
Slide 123
Slide 123 text
A"er
actor UserViewState: ObservableObject {
let userID: User.ID
@Published var user: User?
...
func loadUser() async {
do {
user = try await fetchUser(for: userID)
} catch {
// ΤϥʔϋϯυϦϯά
}
}
}
Slide 124
Slide 124 text
A"er
final class UserViewController: UIViewController {
...
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
state.loadUser() //
}
}
Slide 125
Slide 125 text
A"er
final class UserViewController: UIViewController {
...
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
Task {
await state.loadUser() //
}
}
}
Slide 126
Slide 126 text
A"er
state
.objectWillChange
.receive(on: DispatchQueue.main)
.sink { [self] _ in
// state Λ View ʹө͢Δॲཧ
}
.store(in: &cancellables)
Slide 127
Slide 127 text
A"er
state
.objectWillChange
.receive(on: DispatchQueue.main)
.sink { [self] _ in
// state Λ View ʹө͢Δॲཧ
let user = await state.user
nameLabel.text = user?.name
}
.store(in: &cancellables)
Slide 128
Slide 128 text
A"er
state
.objectWillChange
.receive(on: DispatchQueue.main)
.sink { [self] _ in
// state Λ View ʹө͢Δॲཧ
Task {
let user = await state.user
nameLabel.text = user?.name
}
}
.store(in: &cancellables)
Slide 129
Slide 129 text
Case 19: ΞΫλʔڥքΛӽ͑Δ
Slide 130
Slide 130 text
let user = await state.user
Slide 131
Slide 131 text
struct User {
let id: ID
var name: String
var age: Int
...
}
Slide 132
Slide 132 text
final class User {
let id: ID
var name: String
var age: Int
...
}
Slide 133
Slide 133 text
let user = await state.user //
user?.age += 1 // actor ͷ֎͔Βมߋ
Slide 134
Slide 134 text
final class User {
let id: ID
let name: String
let age: Int
...
}
Slide 135
Slide 135 text
let user = await state.user //
user?.age += 1 //
⛔
Slide 136
Slide 136 text
Sendable ϓϩτίϧSE-0302
SE-0302 h)ps:/
/github.com/apple/swi;-evolu=on/blob/main/proposals/0302-concurrent-value-and-concurrent-
closures.md
Slide 137
Slide 137 text
struct User {
let id: ID
var name: String
var age: Int
...
}
Slide 138
Slide 138 text
struct User: Sendable {
let id: ID
var name: String
var age: Int
...
}
Slide 139
Slide 139 text
final class User: Sendable {
let id: ID
var name: String
var age: Int
...
}
⛔
var ϓϩύςΟΛ࣋ͭͷͰίϯύΠϧΤϥʔ
Slide 140
Slide 140 text
final class User: Sendable {
let id: ID
let name: String
let age: Int
...
}
✅
ΠϛϡʔλϒϧͳͷͰ OK
Slide 141
Slide 141 text
final class User: Sendable {
let id: ID
let name: NSString
let age: Int
...
}
⛔
Sendable Ͱͳ͍ܕͷϓϩύςΟΛ࣋ͭͷͰίϯύΠϧΤϥʔ
Slide 142
Slide 142 text
final class User: Sendable {
let id: ID
let firstName: String
let familyName: String
let age: Int
var name: String {
"\(firstName) \(familyName)"
}
...
}
✅
Computed Property Λ͍࣋ͬͯͯΠϛϡʔλϒϧͳͷͰ OK
Slide 143
Slide 143 text
final class User: Sendable {
let id: ID
let firstName: String
let familyName: String
let age: Int
private var _name: String? //
var name: String {
if _name == nil {
_name = "\(firstName) \(familyName)"
}
return _name!
}
...
}
Slide 144
Slide 144 text
final class User: @unchecked Sendable {
let id: ID
let firstName: String
let familyName: String
let age: Int
private var _name: String? //
var name: String {
if _name == nil {
_name = "\(firstName) \(familyName)"
}
return _name!
}
...
}
Slide 145
Slide 145 text
ϓϩτίϧʹద߹ͤ͞ΒΕͳ͍߹ʁ
Slide 146
Slide 146 text
actor Foo {
func bar(_ f: (String) -> Int) { //
// ...
}
}
Slide 147
Slide 147 text
actor Foo {
func bar(_ f: @Sendable (String) -> Int) { //
// ...
}
}
Ϋϩʔδϟϓϩτίϧʹద߹Ͱ͖ͳ͍ͷͰ @Sendable Λ͏
Slide 148
Slide 148 text
Case 20: ڞ༗͞Εͨঢ়ଶͷมߋ
ϝΠϯεϨου্Ͱͷॲཧ
Slide 149
Slide 149 text
UserViewState ͷΩϡʔ͕
DispatchQueue.main ͩͱ͏Ε͍͠
Slide 150
Slide 150 text
UserViewState ͷΩϡʔ͕ DispatchQueue.main
final class UserViewState: ObservableObject {
private let queue: DispatchQueue = .main
...
}
Slide 151
Slide 151 text
Case 18 (A*er)
// queue Πϯελϯε͝ͱʹࣗಈͰ࡞ΒΕΔ
actor UserViewState: ObservableObject {
...
}
Slide 152
Slide 152 text
Global ActorSE-0316 Ͱܕ
ΠϯελϯεΛӽ͑ͨ Actor Λ࡞Δ
SE-0316 h*ps:/
/github.com/apple/swi<-evolu>on/blob/main/proposals/0316-global-actors.md
Slide 153
Slide 153 text
A"er
@MainActorɹ
final class UserViewState: ObservableObject {
...
}
Slide 154
Slide 154 text
UIViewController h/ps:/
/developer.apple.com/documenta;on/uikit/uiviewcontroller
Slide 155
Slide 155 text
Case 18 (A*er)
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
Task {
await state.loadUser()
}
}
Slide 156
Slide 156 text
A"er
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
state.loadUser()
}
Slide 157
Slide 157 text
Case 18 (A*er)
state
.objectWillChange
.receive(on: DispatchQueue.main)
.sink { [self] _ in
// state Λ View ʹө͢Δॲཧ
Task {
let user = await state.user
nameLabel.text = user?.name
}
}
.store(in: &cancellables)
Slide 158
Slide 158 text
A"er
state
.objectWillChange
.receive(on: DispatchQueue.main)
.sink { [self] _ in
// state Λ View ʹө͢Δॲཧ
nameLabel.text = state.user?.name
}
.store(in: &cancellables)
Slide 159
Slide 159 text
@MainActor @StateObject ʹඞਢ
struct UserView: View {
@StateObject private var state: UserViewState
...
var body: some View {
VStack {
if let user = state.user {
Text(user.name)
}
...
}
.onAppear { state.loadUser() }
}
}
Slide 160
Slide 160 text
ʲ࿕ใʳSwi$ Concurrency iOS 13 Ҏ߱Ͱ
͋Εར༻Մೳʂ#39051
#39051 h)ps:/
/github.com/apple/swi;/pull/39051
Slide 161
Slide 161 text
·ͱΊ
• Concurrency ͰίʔυΛॻ͘ͷָ͕ʹͳΔ
• ͔͠ɺΑΓ҆શʹʂ
• ࠓ݄͔Β͑Δʂʂʂ
Slide 162
Slide 162 text
h"ps:/
/zenn.dev/koher/ar1cles/swi6-
concurrency-cheatsheet