I get many warnings like this when I build an old project.
I asked AI chatbot which gave me several solutions, the recommended one is:
var hashBag = [String: Int]()
func updateHashBag() async {
var tempHashBag = hashBag // make copy
await withTaskGroup(of: Void.self) { group in
group.addTask {
tempHashBag["key1"] = 1
}
group.addTask {
tempHashBag["key2"] = 2
}
}
hashBag = tempHashBag // copy back?
}
My understanding is that in the task group, the concurrency engine ensures synchronized modifications on the temp copy in multiple tasks. I should not worry about this.
My question is about performance.
What if I want to put a lot of data into the bag? Does the compiler do some kind of magics to optimize low level memory allocations? For example, the temp copy actually is not a real copy, it is a special reference to the original hash bag; it is only grammar glue that I am modifying the copy.
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Is there a swift6 manual that will teach me how to code in swift?
I am trying to use initialize a Decimal type using its generic binary integer exactly initializer but it keeps crashing with a fatal error regardless of the value used:
Code to reproduce the issue:
let binaryInteger = -10
let decimal = Decimal(exactly: binaryInteger) // error: Execution was interrupted, reason: EXC_BAD_INSTRUCTION (code=EXC_I386_INVOP, subcode=0x0).
Is it a known bug?
Why Ternary operator in not called a binary Operator or ternary Operands ?
question ? answer1 : answer2
When it takes 2 operators ?
I have a transformation function that takes in data, executes some instructions, and returns an output. This function is dynamic and not shipped with the binary. Currently, I’m executing it using JavaScriptCore.JSContext, which works well, but the function itself is written in JavaScript.
Is there a way to achieve something similar using Swift – such as executing a dynamic Swift script, either directly or through other means? I know this is possible on macOS, but I’m not sure about iOS. I’ve also heard that extensions might open up some possibilities here. Any insights or alternative approaches would be appreciated.
We developing Native App with C++17 for iOS. We override global new and delete operators. This App deallocate all allocated memories correctly by Run on Xcode (Command + R), but exception occurs launch from xcrun or App icon on iPhone.
I debugged the exception. Overriding new operation was called correctly, but overriding delete operation was not called. The default delete was called. I'm not sure why is that.
STEPS TO REPRODUCE
Build xcode project.
Run "xcrun devicectl device install app --device "
Run "xcrun devicectl device process launch --console --device "
PLATFORM AND VERSION
iOS
Development environment: Xcode 16.4, macOS macOS Sequoia 15.5
Run-time configuration: iOS 18.5
main.cpp I attached is sample code to reproduce this problem.
main.cpp
Topic:
Programming Languages
SubTopic:
General
I came across a code
let myFruitBasket = ["apple":"red", "banana": "yellow", "budbeeri": "dark voilet", "chikoo": "brown"]
Can we have range for keys and values of dictionary, it will be convenient
for keys
print(myFruitBasket.keys[1...3])
// banana, budbeeri, chikoo
same for values
print(myFruitsBasket.values[1...3])
// yellow, voilet, brown
In my code I use a binding that use 2 methods to get and get a value. There is no problem with swift 5 but when I swift to swift 6 the compiler fails :
Here a sample example of code to reproduce the problem :
`import SwiftUI
struct ContentView: View {
@State private var isOn = false
var body: some View {
VStack {
Image(systemName: "globe")
.imageScale(.large)
.foregroundStyle(.tint)
Text("Hello, world!")
Toggle("change it", isOn: Binding(get: getValue, set: setValue(_:)))
}
.padding()
}
private func getValue() -> Bool {
isOn
}
private func setValue(_ value: Bool) {
isOn = value
}
}`
Xcode compiler log error :
1. Apple Swift version 6.1.2 (swiftlang-6.1.2.1.2 clang-1700.0.13.5) 2. Compiling with the current language version 3. While evaluating request IRGenRequest(IR Generation for file "/Users/xavierrouet/Developer/TestCompilBindingSwift6/TestCompilBindingSwift6/ContentView.swift") 4. While emitting IR SIL function "@$sSbScA_pSgIeAghyg_SbIeAghn_TR". for <<debugloc at "<compiler-generated>":0:0>>Stack dump without symbol names (ensure you have llvm-symbolizer in your PATH or set the environment var LLVM_SYMBOLIZER_PATH` to point to it):
0 swift-frontend 0x000000010910ae24 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) + 56
1 swift-frontend 0x0000000109108c5c llvm::sys::RunSignalHandlers() + 112
2 swift-frontend 0x000000010910b460 SignalHandler(int) + 360
3 libsystem_platform.dylib 0x0000000188e60624 _sigtramp + 56
4 libsystem_pthread.dylib 0x0000000188e2688c pthread_kill + 296
5 libsystem_c.dylib 0x0000000188d2fc60 abort + 124
6 swift-frontend 0x00000001032ff9a8 swift::DiagnosticHelper::~DiagnosticHelper() + 0
7 swift-frontend 0x000000010907a878 llvm::report_fatal_error(llvm::Twine const&, bool) + 280
8 swift-frontend 0x00000001090aef6c report_at_maximum_capacity(unsigned long) + 0
9 swift-frontend 0x00000001090aec7c llvm::SmallVectorBase::grow_pod(void*, unsigned long, unsigned long) + 384
10 swift-frontend 0x000000010339c418 (anonymous namespace)::SyncCallEmission::setArgs(swift::irgen::Explosion&, bool, swift::irgen::WitnessMetadata*) + 892
11 swift-frontend 0x00000001035f8104 (anonymous namespace)::IRGenSILFunction::visitFullApplySite(swift::FullApplySite) + 4792
12 swift-frontend 0x00000001035c876c (anonymous namespace)::IRGenSILFunction::visitSILBasicBlock(swift::SILBasicBlock*) + 2636
13 swift-frontend 0x00000001035c6614 (anonymous namespace)::IRGenSILFunction::emitSILFunction() + 15860
14 swift-frontend 0x00000001035c2368 swift::irgen::IRGenModule::emitSILFunction(swift::SILFunction*) + 2788
15 swift-frontend 0x00000001033e7c1c swift::irgen::IRGenerator::emitLazyDefinitions() + 5288
16 swift-frontend 0x0000000103573d6c swift::IRGenRequest::evaluate(swift::Evaluator&, swift::IRGenDescriptor) const + 4528
17 swift-frontend 0x00000001035c15c4 swift::SimpleRequest<swift::IRGenRequest, swift::GeneratedModule (swift::IRGenDescriptor), (swift::RequestFlags)17>::evaluateRequest(swift::IRGenRequest const&, swift::Evaluator&) + 180
18 swift-frontend 0x000000010357d1b0 swift::IRGenRequest::OutputType swift::Evaluator::getResultUncached<swift::IRGenRequest, swift::IRGenRequest::OutputType swift::evaluateOrFatalswift::IRGenRequest(swift::Evaluator&, swift::IRGenRequest)::'lambda'()>(swift::IRGenRequest const&, swift::IRGenRequest::OutputType swift::evaluateOrFatalswift::IRGenRequest(swift::Evaluator&, swift::IRGenRequest)::'lambda'()) + 812
19 swift-frontend 0x0000000103576910 swift::performIRGeneration(swift::FileUnit*, swift::IRGenOptions const&, swift::TBDGenOptions const&, std::__1::unique_ptr<swift::SILModule, std::__1::default_deleteswift::SILModule>, llvm::StringRef, swift::PrimarySpecificPaths const&, llvm::StringRef, llvm::GlobalVariable**) + 176
20 swift-frontend 0x0000000102f61af0 generateIR(swift::IRGenOptions const&, swift::TBDGenOptions const&, std::__1::unique_ptr<swift::SILModule, std::__1::default_deleteswift::SILModule>, swift::PrimarySpecificPaths const&, llvm::StringRef, llvm::PointerUnion<swift::ModuleDecl*, swift::SourceFile*>, llvm::GlobalVariable*&, llvm::ArrayRef<std::__1::basic_string<char, std::__1::char_traits, std::__1::allocator>>) + 156
21 swift-frontend 0x0000000102f5d07c performCompileStepsPostSILGen(swift::CompilerInstance&, std::__1::unique_ptr<swift::SILModule, std::__1::default_deleteswift::SILModule>, llvm::PointerUnion<swift::ModuleDecl*, swift::SourceFile*>, swift::PrimarySpecificPaths const&, int&, swift::FrontendObserver*) + 2108
22 swift-frontend 0x0000000102f5c0a8 swift::performCompileStepsPostSema(swift::CompilerInstance&, int&, swift::FrontendObserver*) + 1036
23 swift-frontend 0x0000000102f5f654 performCompile(swift::CompilerInstance&, int&, swift::FrontendObserver*) + 1764
24 swift-frontend 0x0000000102f5dfd8 swift::performFrontend(llvm::ArrayRef<char const*>, char const*, void*, swift::FrontendObserver*) + 3716
25 swift-frontend 0x0000000102ee20bc swift::mainEntry(int, char const**) + 5428
26 dyld 0x0000000188a86b98 start + 6076
Using Xcode 16.4 / Mac OS 16.4
Hello, I have a problem with the .onMove function. I believe I have set everything up properly. However, the moving does not seem to be working correctly. When I try to move the item, it is highlighted first, as it is supposed to be. Then, while I am moving it through the list, it disappears for some reason, and at the end of the move, it comes back to its initial place. (I use iOS 16.0 minimum, so I don't have to include the EditButton(). It works the same in the edit mode tho)
import SwiftUI
struct Animal: Identifiable {
var id = UUID()
var name: String
}
struct ListMove: View {
@State var animals = [Animal(name: "Dog"), Animal(name: "Cat"), Animal(name: "Cow"), Animal(name: "Goat"), Animal(name: "Chicken")]
var body: some View {
List {
ForEach(animals) { animal in
Text(animal.name)
}
.onMove(perform: move)
}
}
func move(from source: IndexSet, to destination: Int) {
animals.move(fromOffsets: source, toOffset: destination)
}
}
#Preview {
ListMove()
}
Crash Log
We have a issue with our watch app. When we do a release build with xcode 16 the watch app will not launch and crashes on watchOS 10 and below devices.
It does not do this on debug builds...and it does not do this on xcode 15 release/debug builds.
Anybody running into watch crashes on xcode 16?
Thanks
Hello together,
since Xcode Version > 15 the following error handling causes following error "Pattern of type 'DecodingError' cannot match 'Never'
func getSupportedCountries() async {
// fetch all documents from collection "seasons" from firestore
let queryCountries = try? await db.collection("countries").getDocuments()
if queryCountries != nil {
self.countries = (queryCountries!.documents.compactMap({ (queryDocumentSnapshot) -> Country? in
let result = Result { try? queryDocumentSnapshot.data(as: Country.self) }
switch result {
case .success(let country):
if let country = country {
// A country value was successfully initialized from the DocumentSnapshot
self.errorMessage = nil
return country
}
else {
// A nil value was successfully initialized from the DocumentSnapshot,
// or the DocumentSnapshot was nil
self.errorMessage = "Document doesn't exist."
return nil
}
case .failure(let error):
// A Country value could not be initialized from the DocumentSnapshot
switch error {
case DecodingError.typeMismatch(_, let context):
self.errorMessage = "\(error.localizedDescription): \(context.debugDescription)"
case DecodingError.valueNotFound(_, let context):
self.errorMessage = "\(error.localizedDescription): \(context.debugDescription)"
case DecodingError.keyNotFound(_, let context):
self.errorMessage = "\(error.localizedDescription): \(context.debugDescription)"
case DecodingError.dataCorrupted(let key):
self.errorMessage = "\(error.localizedDescription): \(key)"
default:
self.errorMessage = "Error decoding document: \(error.localizedDescription)"
}
return nil
}
}))
} else {
self.errorMessage = "No documents in 'countries' collection"
return
}
}
the interesting part of the code where XCODE shows an error is from "switch error" downwards.
Does anyone of you have an idea what's wrong?
Ay help appreciated !
Thx, Peter
Context: SwiftUI TextField with a String for simple math using NSExpression.
I first prepare the input string to an extent but a malformed input using valid characters still fails, as expected. Let's say preparedExpression is "5--"
let expr = NSExpression(format: preparedExpression)
gives
FAULT: NSInvalidArgumentException: Unable to parse the format string "5-- == 1"; (user info absent)
How can I use NSExpression such that either the preparedExpression is pre-tested before asking for actual execution or the error is handled in a polite way that I can use to alert the user to try again.
Is there a Swift alternative to NSExpression that I've missed?
I have a class object created dynamically using Runtime, and I want to release some manually allocated memory resources when this object is deallocated. To achieve this, I added a custom implementation of the dealloc method using the following code:
SEL aSel = NSSelectorFromString(@"dealloc");
class_addMethod(kvoClass, aSel, (IMP)custom_dealloc, method_getTypeEncoding(class_getInstanceMethod(kvoClass, aSel)));
However, I encountered some issues. If I don't call the superclass's dealloc method in the cus_dealloc function, the superclass's dealloc implementation will not be executed. On the other hand, if I explicitly call the superclass's dealloc method, the program crashes.
Here is the implementation of the cus_dealloc function:
void custom_dealloc(id self, SEL _cmd) {
// Release other memory

Class superClass = class_getSuperclass(object_getClass(self));
void (*originIMP)(struct objc_super *, SEL, ...) = (void *)objc_msgSendSuper;
struct objc_super *objcSuper = &(struct objc_super){self, superClass};
originIMP(objcSuper, _cmd);
}
demo
Hello, I have an issue with importing some .mp3 files into a swift playground project (in Xcode, not in the Playground app). They worked fine in the Xcode project, but for some reason playgrounds isn't able to find them. I imported them the exact same way as I did in the Xcode project.
I’m working on a project in Xcode 16.2 and encountered an issue where getAPI() with a default implementation in a protocol extension doesn’t show up in autocomplete. Here’s a simplified version of the code:
import Foundation
public protocol Repository {
func getAPI(from url: String?)
}
extension Repository {
public func getAPI(from url: String? = "https://...") {
getAPI(from: url)
}
}
final class _Repository: Repository {
func getAPI(from url: String?) {
// Task...
}
}
let repo: Repository = _Repository()
repo.getAPI( // Autocomplete doesn't suggest getAPI()
I’ve tried the following without success:
• Clean build folder
• Restart Xcode
• Reindexing
Is there something wrong with the code, or is this a known issue with Xcode 16.2? I’d appreciate any insights or suggestions.
I have a simple shell script as follows:
#!/bin/bash
OUTPUT="network.$(date +'%d-%m-%y').info.txt"
SUPPORT_ID="emailaddress"
echo "---------------------------------------------------" > $OUTPUT
echo "Run date and time: $(date)" >> $OUTPUT
echo "---------------------------------------------------" >> $OUTPUT
ifconfig >> $OUTPUT
echo "---------------------------------------------------" >> $OUTPUT
echo "Network info written to file: $OUTPUT."
echo "Please email this file to: $SUPPORT_ID."
It just dumps the network config into a file. At some point I will have the file emailed out, but right now I'm just trying to figure out why the output looks like the following?
bash ./test.sh
.etwork info written to file: network.26-01-25.info.txt
.lease email this file to: emailaddress
Why in the world does the initial character of the last couple of "echo" commands get clipped and turned into periods? The echos for the output of the commands piped into the output file are fine. Strange...
Any ideas?
Topic:
Programming Languages
SubTopic:
General
Hello everyone,
There is one thing about Objective-C's memory management that confuses me, which is a returned object's lifetime from methods with names doesn't start with "alloc", "new", "copy", or "mutableCopy".
Take this as an example, when using NSBitmapImageRep's representationUsingType:properties: method, it returns an NSData object (reference: https://developer.apple.com/documentation/appkit/nsbitmapimagerep/representation(using:properties:)?language=objc).
While testing this out, the NSData seemed to be an owned object (it doesn't get released until the end of the program).
From what I understand, this may be an auto-released object which is released at the end of an autorelease pool block.
Could someone explain this in more detail? What if I want to release that NSData object before the end of the autorelease pool block? How can I know which object is autoreleased, borrowed, or owned?
Does anyone know if there will be a Swift 6 version of "The Swift Programming Language" book and if so, when it will be released for Apple Books?
Topic:
Programming Languages
SubTopic:
Swift
Hello,
It is mentioned in CryptoTokenKit documentation:
You use the CryptoTokenKit framework to easily access cryptographic tokens. Tokens are physical devices built in to the system, located on attached hardware (like a smart card), or accessible through a network connection.
However, it looks like there is lack of documentation with simple example, how to access network token.
I have a certificates in HSM (hardware secure module), which is accessible on network, and I'd like to access certificates on HSM on my Mac.
Does anybody know, where to start with implementation?
Thank you.
Hello,
I have a test variable here which works fine:
var quotes: [(quote: String, order: Int)] = [
("I live you the more ...", 1),
("There is nothing permanent ...", 2),
("You cannot shake hands ...", 3),
("Lord, make me an instrument...", 4)
]
and I have a test function which successfully pulls data from a mysql database via a web service and displays it via the "print" function:
func getPrice(){
if let url = URL(string:"https://www.TEST.com/test_connection.php"){
URLSession.shared.dataTask(with: url) { (data, response, error) in
if let data = data{
if let json = try? JSONDecoder().decode([[String:String]].self, from: data){
json.forEach { row in
print(row["quote"]!)
print(row["order"]!)
}
}
else{
}
}
else{
print("wrong :-(")
}
}.resume()
}
}
Please can you tell me how to re-write the quotes variable/array so that it returns the results that are found in the getPrice() function?
Topic:
Programming Languages
SubTopic:
Swift