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Need Objective-C translation of DispatchSource.makeFileSystemObjectSource
I came across a useful repo on GitHub: https://github.com/GianniCarlo/DirectoryWatcher/blob/master/Sources/DirectoryWatcher/DirectoryWatcher.swift self.queue = DispatchQueue.global() self.source = DispatchSource.makeFileSystemObjectSource(fileDescriptor: descriptor, eventMask: .write, queue: self.queue) self.source?.setEventHandler { [weak self] in self?.directoryDidChange() } self.source?.setCancelHandler() { close(descriptor) } self.source?.resume() How do I translate this to OC version? I have an app that was written in OC and I plan to incorporate this directory watcher into the project.
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529
Jul ’24
What does ".island" suffix in symbol name mean?
During my analysis of the binary size changes after compiling Swift source code, I discovered symbols with the ".island" suffix. I couldn't find meaningful information about this suffix through my search, so I decided to reach out for assistance. While comparing the changes in binary size after modifying specific code, I noticed a significant increase (from 33MB to 520MB). Upon analyzing the symbols of the enlarged binary using the nm command, I found the following pattern: t _$s12{SomeSymbol}WOb t _$s12{SomeSymbol}WOb.island t _$s12{SomeSymbol}WOb.island2 t _$s12{SomeSymbol}WOb.island3 When I output the symbols of the binary using nm, I noticed many symbols with the same name but different ".island", ".island2", ".island3" suffixes. Disassembling the binary showed that functions with these suffixes simply delegate calls sequentially: x.island3 -> x.island2 -> x.island1 -> x. It appears that these symbols serve as delegates for function calls, but I would like to understand why such duplicated functions with these suffixes are generated. Could someone help me to provide some insights on this matter?
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420
Jul ’24
Bug Report: 'consume' Applied to Unsupported Value
'consume' applied to value that the compiler does not support. This is a compiler bug. Please file a bug with a small example of the bug. public func requestTopicsAndSubTopics() async throws -> (topics: [Topic], subTopics: [String: [SubTopic]]) { var subTopics = [String: [SubTopic]]() let topics = try await getTopics().sorted { $0.index < $1.index } try await withThrowingTaskGroup(of: ([SubTopic], String).self) { [weak self] group in guard let self else { return } for topic in topics { guard let topicId = topic.id else { throw Error.missingId } group.addTask { let subTopics = try await self.getSubtopics(topicId: topicId).sorted { $0.name < $1.name } return (consume subTopics, topicId) } } for try await (resultedSubTopics, topicId) in group { subTopics.updateValue(resultedSubTopics, forKey: topicId) } } return (consume topics, consume subTopics) }
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398
Jul ’24
Link to a Precompiled Static C Library in a Swift Library Package
I want to build a Swift library package that uses modified build of OpenSSL and Curl. I have already statically compiled both and verified I can use them in an Objective-C framework on my target platform (iOS & iOS Simulator). I'm using XCFramework files that contain the static library binaries and headers: openssl.xcframework/ ios-arm64/ openssl.framework/ Headers/ [...] openssl ios-arm64_x86_64-simulator/ openssl.framework/ Headers/ [...] openssl Info.plist I'm not sure how I'm supposed to set up my Swift package to import these libraries. I can use .systemLibrary but that seems to use the embedded copies of libssl and libcurl on my system, and I can't figure out how to use the path: parameter to that. I also tried using a .binaryTarget pointing to the XCFramework files, but that didn't seem to work as there is no module generated and I'm not sure how to make one myself. At a basic high level, this is what I'm trying to accomplish: where libcrypto & libssl come from the provided openssl.xcframework file, and libcurl from curl.xcframework
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886
Jul ’24
Multiple async lets crash the app
Usage of multiple async lets crashes the app in a nondeterministic fashion. We are experiencing this crash in production, but it is rare. 0 libswift_Concurrency.dylib 0x20a8b89b4 swift_task_create_commonImpl(unsigned long, swift::TaskOptionRecord*, swift::TargetMetadata<swift::InProcess> const*, void (swift::AsyncContext* swift_async_context) swiftasynccall*, void*, unsigned long) + 384 1 libswift_Concurrency.dylib 0x20a8b6970 swift_asyncLet_begin + 36 We managed to isolate the issue, and we submitted a technical incident (Case-ID: 8007727). However, we were completely ignored, and referred to the developer forums. To reproduce the bug you need to run the code on a physical device and under instruments (we used swift concurrency). This bug is present on iOS 17 and 18, Xcode 15.1, 15.4 and 16 beta, swift 5 and 6, including strict concurrency. Here's the code for Swift 6 / Xcode 16 / strict concurrency: (I wanted to attach the project but for some reason I am unable to) typealias VoidHandler = () -> Void enum Fetching { case inProgress, idle } protocol PersonProviding: Sendable { func getPerson() async throws -> Person } actor PersonProvider: PersonProviding { func getPerson() async throws -> Person { async let first = getFirstName() async let last = getLastName() async let age = getAge() async let role = getRole() return try await Person(firstName: first, lastName: last, age: age, familyMemberRole: role) } private func getFirstName() async throws -> String { try await Task.sleep(nanoseconds: 1_000_000_000) return ["John", "Kate", "Alex"].randomElement()! } private func getLastName() async throws -> String { try await Task.sleep(nanoseconds: 1_400_000_000) return ["Kowalski", "McMurphy", "Grimm"].randomElement()! } private func getAge() async throws -> Int { try await Task.sleep(nanoseconds: 2_100_000_000) return [56, 24, 11].randomElement()! } private func getRole() async throws -> Person.Role { try await Task.sleep(nanoseconds: 500_000_000) return Person.Role.allCases.randomElement()! } } @MainActor final class ViewModel { private let provider: PersonProviding = PersonProvider() private var fetchingTask: Task<Void, Never>? let onFetchingChanged: (Fetching) -> Void let onPersonFetched: (Person) -> Void init(onFetchingChanged: @escaping (Fetching) -> Void, onPersonFetched: @escaping (Person) -> Void) { self.onFetchingChanged = onFetchingChanged self.onPersonFetched = onPersonFetched } func fetchData() { fetchingTask?.cancel() fetchingTask = Task { do { onFetchingChanged(.inProgress) let person = try await provider.getPerson() guard !Task.isCancelled else { return } onPersonFetched(person) onFetchingChanged(.idle) } catch { print(error) } } } } struct Person { enum Role: String, CaseIterable { case mum, dad, brother, sister } let firstName: String let lastName: String let age: Int let familyMemberRole: Role init(firstName: String, lastName: String, age: Int, familyMemberRole: Person.Role) { self.firstName = firstName self.lastName = lastName self.age = age self.familyMemberRole = familyMemberRole } } import UIKit class ViewController: UIViewController { @IBOutlet private var first: UILabel! @IBOutlet private var last: UILabel! @IBOutlet private var age: UILabel! @IBOutlet private var role: UILabel! @IBOutlet private var spinner: UIActivityIndicatorView! private lazy var viewModel = ViewModel(onFetchingChanged: { [weak self] state in switch state { case .idle: self?.spinner.stopAnimating() case .inProgress: self?.spinner.startAnimating() } }, onPersonFetched: { [weak self] person in guard let self else { return } first.text = person.firstName last.text = person.lastName age.text = "\(person.age)" role.text = person.familyMemberRole.rawValue }) @IBAction private func onTap() { viewModel.fetchData() } }
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558
Jul ’24
Decoding JSON with a reserved property name
I need to decode JSON into a class. The JSON has a field called "Type", and I cannot declare a property with that name in my class since Type is a reserved word. I tried declaring CodingKeys, but that doesn't work unless I declare EVERY property in the CodingKeys. This class has about a hundred properties and I have others like it, I do not want to do this. Is there a better solution?
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371
Jul ’24
Failed to produce diagnostic for expression; please submit a bug report
I got the error and I don’t how can I fix it help please struct MovieDetail: View { var movie: Movie let screen = UIScreen.main.bounds @State private var showSeasonPicker = true @State private var selectedSeason = 0 var body: some View { ZStack { Color.black .ignoresSafeArea() ZStack { VStack { HStack { Spacer() Button() { // Closing Button }label: { Image(systemName: "xmark.circle") .font(.system(size: 28)) } } .padding(.horizontal, 22) ScrollView (.vertical, showsIndicators: false){ VStack { StandardHomeMovie(movie: movie) .frame(width: screen.width / 2.5) MovieInfoSubheadline(movie: movie) if movie.promotionHeadline != nil { Text(movie.promotionHeadline!) .bold() .font(.headline) } PlayButton(text: "Play", imagename: "play.fill", backgroundColor: .red) { // } CurrentEpisodeInformation(movie: movie) CastInfo(movie: movie) HStack(spacing: 60){ SmallVerticalButton(text: "My List", isOnImage: "checkmark", isOffImage: "plus", isOn: true) { // } SmallVerticalButton(text: "Rate", isOnImage: "hand.thumbsup.fill", isOffImage: "hand.thumbsup", isOn: true) { // } SmallVerticalButton(text: "Share", isOnImage: "square.and.arrow.up", isOffImage: "square.and.arrow.up", isOn: true) { // } Spacer() } .padding(.leading, 20) CustomTabSwitcher(tabs: [.episodes, .trailers, .more], movie: movie, showSeasonPicker: $showSeasonPicker, selectedSeason: $selectedSeason) } .padding(.horizontal, 10) } Spacer() } .foregroundStyle(.white) if showSeasonPicker { Group { Color.black.opacity(0.9) VStack(spacing: 40){ Spacer() ForEach(0..<(movie.numberOfSeasons ?? 0)) { season in Button(action: { self.selectedSeason = (season != 0) self.showSeasonPicker = false }, label: { Text("Season: \(season + 1)") .foregroundStyle(selectedSeason == season + 1 ? .white : .gray) .bold() .font(.title2) }) } Spacer() Button(action: { self.showSeasonPicker = false }, label: { Image(systemName: "xmark.circle.fill") .foregroundStyle(.white) .font(.system(size: 40)) .scaleEffect(x: 1.1) }) .padding(.bottom, 30) } } .ignoresSafeArea() } } } } } #Preview { MovieDetail(movie: exampleMovie2) } struct MovieInfoSubheadline: View { var movie: Movie var body: some View { HStack(spacing: 20){ Image(systemName: "hand.thumbsup.fill") .foregroundStyle(.white) Text(String(movie.year)) RatingView(rating: movie.rating) Text(movie.numberOfSeasonsDisplay) ZStack{ Text("HD") .foregroundStyle(.white) .font(.system(size: 12)) .bold() Rectangle() .stroke(.gray, lineWidth: 2) .frame(width: 30, height: 20) } } .foregroundStyle(.gray) .padding(.vertical, 6) } } struct RatingView: View { var rating: String var body: some View { ZStack { Rectangle() .foregroundStyle(.gray) Text(rating) .foregroundStyle(.white) .font(.system(size: 12)) .bold() } .frame(width: 50, height: 20) } } struct CastInfo: View { var movie: Movie var body: some View { VStack(spacing: 3) { HStack { Text("Cast: \(movie.cast)") Spacer() } HStack { Text("Creaters: \(movie.creaters)") Spacer() } } .font(.caption) .foregroundStyle(.gray) .padding(.vertical, 10) } } struct CurrentEpisodeInformation: View { var movie: Movie var body: some View { Group { HStack { Text(movie.episodeInfoDisplay) .bold() Spacer() } .padding(.vertical, 4) HStack { Text(movie.episodeDescriptionDisplay) .font(.subheadline) Spacer() } } } }
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Jul ’24
iOS Developer Beta 18
I want to ask about NSDecimalNumber. is it any changes for use this function ? i test use number like this. example: a = "1000000.0" var a i make number formatter use NumberFormatter b = NSDecimalNumber(string: a with number formatter).decimalValue i try to print b. the value return 1. Anyone can help ?
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675
Jul ’24
Issue with Swift and C++ Interoperability: Passing void pointer between Swift and C++
Hello everyone, I'm encountering an issue with Swift and C++ interoperability when passing a void pointer between Swift and C++ functions. When I pass pMessageBuffer (an UnsafeMutableRawPointer) from Swift to MyCppClass.NFCompletion (a static c++ function), which expects a reference to void pointer, Swift throws an error "Cannot convert value of type 'UnsafeMutableRawPointer' to expected argument type 'Optional' ". Here is a sample code to help in better visualization of the usecase. Cpp Code class MyCppClass { public: static void SendData(void *pMessage, TUInt16 pMessageLength) { // Assume vSocket is my Swift object held in C++. vSocket.Send(pMessage, pMessageLength); } static void NFCompletion(void * & pBuffer, TInt64 pErrorCode, VPtr pCompletionFunction) { // Process the buffer. } }; Swift Code: public class MySwiftClass { var vConnection: NWConnection? public init() {} public func Send(_ pMessageBuffer: UnsafeMutableRawPointer, _ pMessageLength: TSUInt16) { let messageData = Data(bytesNoCopy: pMessageBuffer, count: Int(pMessageLength), deallocator: .none) self.vConnection?.send(content: messageData, completion: .contentProcessed { nw_error in var error_code: TSInt64 = 0 if let nw_error = nw_error { error_code = self.InternalGetNetworkErrorCode(nw_error) } // Here's where the issue arises: MyCppClass.NFCompletion(pMessageBuffer, TInt64(error_code), self.uCompletionHandler) }) } // Example function to handle network errors private func InternalGetNetworkErrorCode(_ error: Error) -> TSInt64 { // Implementation to convert nw_error to TSInt64 error code return 0 // Placeholder return value } } Could someone please help me understand why this conversion error occurs? How should I correctly handle passing a void pointer between Swift and C++ functions, ensuring compatibility and proper memory management? Note: TSInt64 is typealias for swift Int and TInt64 is alias of c++ int_64t. Thank you in advance for your assistance! Regards, Harshal
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430
Jun ’24
Swift Syntax Comment Trivia - Expected prefixes
Hello! I am working on a project that does some automatic code generation using SwiftSyntax and SwiftSyntaxBuilder. As part of this project, I want to put in a comment at the top of the file warning users to not modify the file and make it obvious that the code was automatically generated. I was trying to use the .lineComment(String) static member of the Trivia (or TriviaPiece) types and I expected that the comment would automatically be prefixed with the expected // and space for use in code. (For example, Trivia.lineComment("No comment") would be written as // No Comment when sent through a BasicFormat Object or similar SyntaxRewriter). I was surprised to find that this is not the case and was wondering before I write an issue on GitHub whether this behavior is intentional or a bug. If it is intentional, I'm not entirely sure if I'm missing something regarding this to more easily generate these comments. At the moment my comment generation consists of constructing the comment in the leadingTrivia of the syntax node that appears after the comment. For example: VariableDeclSyntax(leadingTrivia: [.newlines(2), .lineComment("// These members are always generated irrespective of the contents of the generated files. They are intended to exclusively centralize code symbols that would otherwise be repeated frequently."), .newlines(1)], modifiers: [DeclModifierSyntax(name: .keyword(.private)), DeclModifierSyntax(name: .keyword(.static))], .let, name: PatternSyntax(IdentifierPatternSyntax(identifier: "decoder")), initializer: InitializerClauseSyntax(value: ExprSyntax(stringLiteral: "\(configuration.decoderExpression)"))) outputs // These members are always generated irrespective of the contents of the generated files. They are intended to exclusively centralize code symbols that would otherwise be repeated frequently. private static let decoder = JSONDecoder() in this project (with example data having been added).
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453
Jun ’24
Swift Async/Await, how to bring asynchronously calculated results back to main thread
I'm relatively new to Swift, and very new to concurrency via Async/Await, so please be patient. 😀 I'm having a hard time comprehending how to do complex operations asynchronously in background threads, and then in turn bring the results back to the main thread. I'm getting various errors along the lines of "Mutation of captured var 'personName' in concurrently-executing". I've paired the issue down as simply as possible as follows, and you'll see where the compiler gives the error message. I'd appreciate any advice on how to evolve my mental model to make this work. Thanks! Bruce import Foundation actor Person {     var myName = "Thomas Jefferson"     var name: String {         get {             return myName         }     } } func main() {     let person = Person()     var personName: String     print("start")     let nameTask = Task {         return await person.name     }     Task {         do {             personName = try await nameTask.result.get()             // Error: Mutation of captured var 'personName' in concurrently-executing code         } catch {             print("error!!!")         }     }     print("The person's name is \(personName)") } RunLoop.main.run() main()
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4.0k
Mar ’23
Cast Any to Sendable
I'm continuing with the migration towards Swift 6. Within one of our libraries, I want to check whether a parameter object: Any? confirms to Sendable. I tried the most obvious one: if let sendable = object as? Sendable { } But that results into the compiler error "Marker protocol 'Sendable' cannot be used in a conditional cast". Is there an other way to do this?
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588
Jul ’24
LOCALIZED_STRING_MACRO_NAMES for Swift package targets?
I have a custom localisation function in my project that enforces the inclusion of the bundle parameter (specifically so that Swift packages are forced to include the Bundle.module value). While migrating to String Catalogs, I noticed that my custom localisation function wasn't being recognised by the automatic extraction that the Swift compiler is doing, but only in my Swift package targets. Is there a way to set something like LOCALIZED_STRING_MACRO_NAMES in Swift Packages?
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577
Jul ’24