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Where is help on Swift documentation markup?
I am reluctant to admit that I only came to know that Swift provides a builtin documentation markup syntax just a few months ago. /** Test func Some description here. - Parameters: - b:Test - d: Test - f: Test - Returns: Bool */ func myMethod(a b:Int, c d:Int, e f:Int) -> Bool { b > d } It seems the markup is pretty simple and has only a few keywords. But, I want to read through the complete reference. Any useful pointers?
2
0
1.1k
Dec ’23
Environment variable not working in another user account
I have the following in my .zshrc: export MY_LIBRARY_DIR=~/bin In Xcode I can set header/lib search path using something like $(MY_LIBRARY_DIR)/abc. This works fine in my daily used user account. But today I found that this technique does not work in a test user account (for testing purpose only). I even reboot my machine but still can't get it working. Am I missing something very obvious??? BTW, I am using Xcode 14.2 and 14.3.1.
1
0
745
Dec ’23
How read image file metadata?
I want to read metadata of image files such as copyright, author etc. I did a web search and the closest thing is CGImageSourceCopyPropertiesAtIndex: - (void)tableViewSelectionDidChange:(NSNotification *)notif { NSDictionary* metadata = [[NSDictionary alloc] init]; //get selected item NSString* rowData = [fileList objectAtIndex:[tblFileList selectedRow]]; //set path to file selected NSString* filePath = [NSString stringWithFormat:@"%@/%@", objPath, rowData]; //declare a file manager NSFileManager* fileManager = [[NSFileManager alloc] init]; //check to see if the file exists if ([fileManager fileExistsAtPath:filePath] == YES) { //escape all the garbage in the string NSString *percentEscapedString = (NSString *)CFURLCreateStringByAddingPercentEscapes(NULL, (CFStringRef)filePath, NULL, NULL, kCFStringEncodingUTF8); //convert path to NSURL NSURL* filePathURL = [[NSURL alloc] initFileURLWithPath:percentEscapedString]; NSError* error; NSLog(@"%@", [filePathURL checkResourceIsReachableAndReturnError:error]); //declare a cg source reference CGImageSourceRef sourceRef; //set the cg source references to the image by passign its url path sourceRef = CGImageSourceCreateWithURL((CFURLRef)filePathURL, NULL); //set a dictionary with the image metadata from the source reference metadata = (NSDictionary *)CGImageSourceCopyPropertiesAtIndex(sourceRef,0,NULL); NSLog(@"%@", metadata); [filePathURL release]; } else { [self showAlert:@"I cannot find this file."]; } [fileManager release]; } Is there any better or easy approach than this?
1
0
1.1k
Dec ’23
What should I do with UTI (NSImage.imageTypes)?
Per the docs, NSImage.imageTypes returns a list UTI's, something like below: com.adobe.pdf com.apple.pict com.adobe.encapsulated-postscript public.jpeg public.png com.compuserve.gif com.canon.tif-raw-image ... What I need is get file extensions of a UTI. For example, public.jpeg picture file may have several file extensions, say .jpg,.jpeg,.jfif. Does Cocoa provide any API to query for this information?
2
0
1.2k
Dec ’23
Weird problem of NSTableView with auto layout
I have had this issue for a long time. If I configure any auto layout constraints in TableViewCell, I get extremely weird layout behavior in IB designer; however, layout is completely good during runtime. For example, with a completely new project and a single NSTableView on the main view, I get: If I resize main view, the tableview won't get resized Every time I reopen the project, the tableview would shrink by height. It seems the shrinked height is doubled every time. For example, in the following screenshot, the gap is 56. Next reopen will double the gap to 112. Is this a known bug? I would want to file bug report at https://feedbackassistant.apple.com.
1
1
676
Nov ’23
Is it safe to call low level Darwin function on FileHandle?
I have the following code: extension FileHandle { func readInto(_ buffer: inout [UInt8]) -> Int { buffer.withUnsafeMutableBytes { Darwin.read(fileDescriptor, $0.baseAddress, $0.count) } } } It can compile, but I wonder if this is supported since it's code in an app that is going to be submitted to App Store. The reason I don't use read(upToCount:) or readData(ofLength:) is that I am reading possibly very large files by small chunks and don't want to let Swift runtime allocate small buffers repeatedly.
0
0
327
Nov ’23
Data(contentsOf:) with huge file
I have a function that computes MD5 hash of a file: func ComputeMD5(ofFile path: String) -> [UInt8]? { if let data = try? Data(contentsOf: URL(fileURLWithPath: path)) { var digest = [UInt8](repeating: 0, count: 16) data.withUnsafeBytes { _ = CC_MD5($0.baseAddress, UInt32(data.count), &digest) } return digest } return nil } Now I wonder/worry what happens if the file is very huge. Does the runtime perform disk memory paging?
2
1
733
Nov ’23
Is there any way to tell if a file is on SSD volume?
I have a need to optimize reading strategy, based on if the file is on hard disk or SSD. Does macOS provide any low-level API so that I can query such information?
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2
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0
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644
Activity
Jan ’24
Where is help on Swift documentation markup?
I am reluctant to admit that I only came to know that Swift provides a builtin documentation markup syntax just a few months ago. /** Test func Some description here. - Parameters: - b:Test - d: Test - f: Test - Returns: Bool */ func myMethod(a b:Int, c d:Int, e f:Int) -> Bool { b > d } It seems the markup is pretty simple and has only a few keywords. But, I want to read through the complete reference. Any useful pointers?
Replies
2
Boosts
0
Views
1.1k
Activity
Dec ’23
NSWorkspace.shared.isFilePackage
I vaguely remember I came across some classes about file packages. Just cannot recall the exact names. Can anyone help?
Replies
2
Boosts
0
Views
508
Activity
Dec ’23
Environment variable not working in another user account
I have the following in my .zshrc: export MY_LIBRARY_DIR=~/bin In Xcode I can set header/lib search path using something like $(MY_LIBRARY_DIR)/abc. This works fine in my daily used user account. But today I found that this technique does not work in a test user account (for testing purpose only). I even reboot my machine but still can't get it working. Am I missing something very obvious??? BTW, I am using Xcode 14.2 and 14.3.1.
Replies
1
Boosts
0
Views
745
Activity
Dec ’23
Is there any way to get static var's in a type using Mirror?
Does Swift support this? Til now my understanding is that reflection only works with public members. Is it possible to get private/static members of a type?
Replies
2
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0
Views
534
Activity
Dec ’23
How read image file metadata?
I want to read metadata of image files such as copyright, author etc. I did a web search and the closest thing is CGImageSourceCopyPropertiesAtIndex: - (void)tableViewSelectionDidChange:(NSNotification *)notif { NSDictionary* metadata = [[NSDictionary alloc] init]; //get selected item NSString* rowData = [fileList objectAtIndex:[tblFileList selectedRow]]; //set path to file selected NSString* filePath = [NSString stringWithFormat:@"%@/%@", objPath, rowData]; //declare a file manager NSFileManager* fileManager = [[NSFileManager alloc] init]; //check to see if the file exists if ([fileManager fileExistsAtPath:filePath] == YES) { //escape all the garbage in the string NSString *percentEscapedString = (NSString *)CFURLCreateStringByAddingPercentEscapes(NULL, (CFStringRef)filePath, NULL, NULL, kCFStringEncodingUTF8); //convert path to NSURL NSURL* filePathURL = [[NSURL alloc] initFileURLWithPath:percentEscapedString]; NSError* error; NSLog(@"%@", [filePathURL checkResourceIsReachableAndReturnError:error]); //declare a cg source reference CGImageSourceRef sourceRef; //set the cg source references to the image by passign its url path sourceRef = CGImageSourceCreateWithURL((CFURLRef)filePathURL, NULL); //set a dictionary with the image metadata from the source reference metadata = (NSDictionary *)CGImageSourceCopyPropertiesAtIndex(sourceRef,0,NULL); NSLog(@"%@", metadata); [filePathURL release]; } else { [self showAlert:@"I cannot find this file."]; } [fileManager release]; } Is there any better or easy approach than this?
Replies
1
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0
Views
1.1k
Activity
Dec ’23
Common audio/image file extensions on macOS
I have a need to list all known audio/image file types in a planned app. What I have known so far: images .apng .avi, .avif .gif .jpg, .jpeg, .jfif, .pjpeg, .pjp .png .svg .webp audio .aif .cda .mid, .midi .mp3 .mpa .ogg .wav .wma What are the missing ones?
Replies
2
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0
Views
972
Activity
Dec ’23
What should I do with UTI (NSImage.imageTypes)?
Per the docs, NSImage.imageTypes returns a list UTI's, something like below: com.adobe.pdf com.apple.pict com.adobe.encapsulated-postscript public.jpeg public.png com.compuserve.gif com.canon.tif-raw-image ... What I need is get file extensions of a UTI. For example, public.jpeg picture file may have several file extensions, say .jpg,.jpeg,.jfif. Does Cocoa provide any API to query for this information?
Replies
2
Boosts
0
Views
1.2k
Activity
Dec ’23
Does Swift support number suffixes?
In C++, I can write 123457890ull to imply it's an unsigned long long integer. Does Swift provide similar language construct?
Replies
3
Boosts
0
Views
720
Activity
Nov ’23
How parse byte size strings into actual number?
I want to convert byte size strings like "1234kb", "100mb" or "5gb" to their actual number representation. Is there any builtin functions for this purpose?
Replies
2
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0
Views
476
Activity
Nov ’23
Is it possible to convert String.Index to its underlying index number?
I am aware Swift deliberately hides details (the actual index number) for safety, by introducing this verbose construct. But I just got curious - is it possible to convert Index back to its underlying number?
Replies
1
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0
Views
859
Activity
Nov ’23
Array withUnsafeMutableBytes(_:) vs withUnsafeMutableBufferPointer(_:)
I cannot get any clue on the differences between these 2 functions of Array type. Can anyone explain by examples?
Replies
1
Boosts
0
Views
358
Activity
Nov ’23
Weird problem of NSTableView with auto layout
I have had this issue for a long time. If I configure any auto layout constraints in TableViewCell, I get extremely weird layout behavior in IB designer; however, layout is completely good during runtime. For example, with a completely new project and a single NSTableView on the main view, I get: If I resize main view, the tableview won't get resized Every time I reopen the project, the tableview would shrink by height. It seems the shrinked height is doubled every time. For example, in the following screenshot, the gap is 56. Next reopen will double the gap to 112. Is this a known bug? I would want to file bug report at https://feedbackassistant.apple.com.
Replies
1
Boosts
1
Views
676
Activity
Nov ’23
Is it safe to call low level Darwin function on FileHandle?
I have the following code: extension FileHandle { func readInto(_ buffer: inout [UInt8]) -> Int { buffer.withUnsafeMutableBytes { Darwin.read(fileDescriptor, $0.baseAddress, $0.count) } } } It can compile, but I wonder if this is supported since it's code in an app that is going to be submitted to App Store. The reason I don't use read(upToCount:) or readData(ofLength:) is that I am reading possibly very large files by small chunks and don't want to let Swift runtime allocate small buffers repeatedly.
Replies
0
Boosts
0
Views
327
Activity
Nov ’23
Data(contentsOf:) with huge file
I have a function that computes MD5 hash of a file: func ComputeMD5(ofFile path: String) -> [UInt8]? { if let data = try? Data(contentsOf: URL(fileURLWithPath: path)) { var digest = [UInt8](repeating: 0, count: 16) data.withUnsafeBytes { _ = CC_MD5($0.baseAddress, UInt32(data.count), &digest) } return digest } return nil } Now I wonder/worry what happens if the file is very huge. Does the runtime perform disk memory paging?
Replies
2
Boosts
1
Views
733
Activity
Nov ’23