Swift concurrency ngidini sampeyan nulis kode asinkron sing kewaca kaya kode sinkron nganggo async/await, dene compiler meksa keamanan saka data-race. Task miwiti gawean concurrent, actor nglindhungi mutable state, lan @MainActor njamin kode UI mlaku ing main thread.
await menehi tandha suspension point: fungsi bisa mandheg ing kono, mbebasake thread kanggo gawean liya, lan nerusake nalika nilai sing ditunggu wis siap — ora ana callback, ora ana thread sing keblok.
func loadProfile() async throws -> Profile {
let user = try await fetchUser() // suspends, thread reused
let posts = try await fetchPosts(user) // runs after user resolves
return Profile(user: user, posts: posts)
}
// Start async work from a sync context
Task {
let profile = try await loadProfile()
await MainActor.run { render(profile) } // UI update on main thread
}
Sawijining actor nyerialake akses menyang mutable state-e — mung siji task sing nyenggol ing saben wektu, mula ora butuh lock lan ora ana data race.
actor ImageCache {
private var store: [URL: Image] = [:]
func image(for url: URL) -> Image? { store[url] } // isolated
func insert(_ img: Image, for url: URL) { store[url] = img }
}
@MainActor
final class ViewModel: ObservableObject { // all members run on main thread
@Published var title = ""
}
async let lan TaskGroup mlakokake anak-anak kanthi paralel lan nunggu kabeh bareng; mbatalake parent bakal mbatalake anak-anake.
async let a = fetchA() // both start immediately, in parallel
async let b = fetchB()
let (x, y) = try await (a, b)
@MainActor ing update UI nyebabake peringatan "Publishing changes from background thread".Task { } marisi konteks actor; Task.detached ora — gunakake iki kanthi ngati-ati.async/await nggenteni completion handler sing nested jero ("callback hell") lan saiki compiler nyekel data race nalika build time. Pewawancara mriksa apa sampeyan ngerti suspension point, isolasi actor, lan @MainActor — model sing ndadekake concurrency iOS modern kewaca lan aman.
Pustaka pitakon wawancara IT kanthi jawaban rinci — saka Junior nganti Senior.
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