I just want some experts on Swift to confirm that the following syntaxes are equivalent:
if a > b, c > d {
}
if a > b && c > d {
}
I consulted "The Swift Programming Lanugage (version 5.7)" but the book does not cover this issue. But I believe it's true because my tests show they are the same.
I remember long time ago I could click on a button in Xcode to launch a Web page to manage iCloud data. But now I cannot find the button.
I want to check if a given string matches a file pattern.
Does Swift have builtin support for filename globbing? Or is there any 3rd party packages for this?
I had a customer feedback about a "zero length data" error which was captured using an exception handler and displayed using NSAlert.
My app employs [NSURLSession dataTaskWithURL:] to download XML and image data.
But I got no idea what it is about. I assume it's related to NSData, but this error never happened before (for years).
Does anyone have any idea about the source of this error?
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I used to run VirtualBox on macOS to run Windows guests for some reasons.
Recently I bought a new Mac mini M1, now I have a problem - VB does not have a stable release for arm (yet).
What other options do I have?
BTW, I came across this doc article (https://developer.apple.com/documentation/virtualization/running_macos_in_a_virtual_machine_on_apple_silicon). I read thru it, but could not conclude if it offers the same functionalities as a full-blown VM suite; and more specifically I want to run Windows guests.
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Is it possible that I bypass tableView.makeView so that I can create a NSTableCellView on the fly (based on some logics)?
func tableView(_ tableView: NSTableView, viewFor tableColumn: NSTableColumn?, row: Int) -> NSView? {
if NSTableColumn.identifier.rawValue == "labelColumn" {
let myCellView = NSTableCellView()
myCellView.textField.strinValue = "label text"
return myCellView
} else {
let complexView = loadFromNib() // of NSTableCellView
// populate complexView
return complexView
}
}
Does Swift has the syntax that lets me get the default value of a template type T, like below:
struct VarLock<T> {
private var v = default(T) // or T()
}
I know this is a frequently asked question, but...
After reading many articles on the net, I am still not sure if I have a solid understanding of the logics behind the design.
One of my puzzles around this question is - Is the Swift compiler clever enough so that I can solely rely on its warnings/errors?
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I have used URL like "macappstore://itunes.apple.com/app/idxxx" in my apps for several years.
Just curious to know if there is any update from this URL scheme? I believe iTunes is not app specific any more (or I am wrong).
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Is there any way to get an unnamed property of a tuple given its position?
Like below:
let record = ("field1", "field2")
func getRecordFieldValue(at: Int, of record: (String, String)) -> Any? {
// pseudo code
record.[at]
}
Suppose I have the following function:
func doWork(_ someValue: Int, completionHandler: () -> Void) {
let q = DispatchQueue()
q.async {
// Long time of work
completionHandler()
}
}
How do I turn it into async function so that I can call it using await doWork()? Are there guidelines/principles/practices for this purpose?
I have the following pseudo code:
func load(at packageURL: URL) {
let realPackageURL = packageURL.resolvingSymlinksInPath()
guard let it = fileMan.enumerator(at: realPackageURL)
for case let fileURL as URL in it {
print(fileURL)
// Get filename relative to package root directory
let relativeFileName = String(filePath.suffix(filePath.count - packagePath.count))
}
}
When called with "file:///tmp/some.app", the enumerated fileURL is actually
file:///private/tmp/GIMP.app/Contents/
packageURL.resolvingSymlinksInPath() actually does nothing, I assume /tmp is a hard link.
This makes it impossible to get a correct relative path. Is there any remedy for this?
I have a need to read first half and second half of a file concurrently. Is there any best practices for this scenario?
BTW, I did research on DispatchIO but it turned out DispatchIO is all about asynchronous operations on a single file handle; it cannot perform parallel reading.
// naive approach
Task {
fileHandle.read(into:buffer)
}
Task {
// seek to file size / 2
fileHandle.read(into:buffer)
}
I want to optimize file reading performance. I believe DispatchIO is the solution. Can anyone give some good pointers?
Does Swift provide such shorthand/sugar syntax for commonly used thread synchronization?
imneo.