In other languages, I usually have a StringBuilder class that provides the functionality to concatenate strings in an efficient way.
// pseudo code
let sb = StringBuilder()
sb.append("text")
sb.appendFormat("name=%@", name)
I am aware of @resultBuilder, but does Swift provide a builtin construct?
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I have a need to wrap several kinds of objects into a dictionary say [String: Any?], but how do I tell that the Any? object is all Encodable?
let params: [String: Any?] = ["num": 123, "text": "abc", "obj": encodableobject]
JSONEncoder().encode(params) // compiler error because Any? is not Encodable
I am trying to encode/decode JSON data, and I have the following code:
struct SomeOrdinaryClass: Decodable {
// ...
}
struct SomeBox<T>: Decodable {
var data: T?
}
But Xcode gives me the following error:
myfile.swift:16:8 Type 'SomeBox' does not conform to protocol 'Decodable'
Is there anyway to overcome this?
I have to admit that this is strange for me. Though I have been using playgrounds for years, but I only write small pieces of code to test simple ideas, and I never used another source file.
Today I want to add a new struct in Sources folder. To my surprise, I am not able to reference the struct in the main playground file.
Sources/testlets.swift:
struct Dummy {
var name: String
}
MyPlayground:
var box = Dummy(name: "abc")
// error: /.../MyPlayground.playground:22:11 Cannot find 'Dummy' in scope
A simple question, but I am not able to find the answer myself.
Note - I tried ProcessInfo.environment but it does not include system env vars.
I am reading "Managing Strings Files Yourself".
Now the question arises in my mind. Is it possible to add new localizations using ibtool (or alike)?
The reason I have this question is that I have a plan to build an app to automate strings localization so that I will be freed from tedious and repetitive work on translation.
I remember last time I could download epub book (5.7) of the Swift language from https://www.swift.org. But now I cannot find the link. Where is the link now?
This is really disgusting. I really hate to say this.
I started Xcode programming many years ago when it's at version 4 (or even 3). It has been fun and pleasure to program in this IDE, with no problem at all. User rating of this app in App Store was 4.5+.
But 2 or 3 years ago, maybe starting from Xcode 11, it started getting too many quirks/gotchas. App Store user rating drops to 3.5+.
With version 14+, user rating drops to 2.9.
The app's key/main features work. But many small bugs/nuisances put developers like me into peril during daily coding work.
Now I almost want to quit Xcode programming, because it is making my life unpleasant.
Not sure if it's specific to me only. I tried to build a framework project using Xcode 14.3.1 RC but got a strange error:
File not found: /Users/USERNAME/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/arc/libarclite_macosx.a
The project was created several years ago and was upgraded all the way to Xcode 14.2.
I remember last time I posted a question about getting an empty xcarchive when doing archive build. The remedy is quite simple - setting SKIP_INSTALL to no.
I wonder if this problem also has a simple remedy.
I have not touched Swift code for more than a year. My skills become rusty.
I am not sure what stupid errors I made in the following code:
extension Bundle {
func readResourceFile(_ filename: String) -> String? {
if let fileUrl = self.resourceURL?.appendingPathComponent(filename, isDirectory: false) {
return try? String(contentsOf: fileUrl)
}
return nil
}
}
class MyVC {
//...
@IBAction func testButton_click(_ sender: Any) {
Task.init { await self.test1() }
}
func test1() async {
var loaded = false
do {
let result = try await self.webView.evaluateJavaScript("typeof(jQuery)")
loaded = result as? String == "function"
} catch {
self.statusLabel.stringValue = "error: \(error)"
}
if (loaded) {
await self.runUserScript(self.input.string)
return
}
let scriptFiles = ["jQuery.js", "Scriptlets.js"]
var count = 0
for scriptFile in scriptFiles {
print("Loading \(scriptFile)")
do {
if let script = Bundle.main.readResourceFile(scriptFile) {
try await self.webView.evaluateJavaScript(script)
print("Loaded \(scriptFile)")
count += 1
}
} catch {
self.statusLabel.stringValue = "error: \(error)"
}
}
}
The line if let script = Bundle.main.readResourceFile(scriptFile) { succeeds but script still is nil and causes app crash in next line self.webView.evaluateJavaScript(script).
Bundle.main.readResourceFile(scriptFile) is working if I run this line elsewhere.
EDIT:
When I click on the I button in debugging on variable script I get:
(String) script = <no location, value may have been optimized out>
However, I can print(script) and the output is correct.
I am testing with FSEventStreamCreate which returns an FSEventStreamRef, but I cannot find an equivalent toll-free class in Cocoa.
In order to free-up resources used by this Ref, I need to do following:
FSEventStreamStop(stream);
FSEventStreamInvalidate(stream);
FSEventStreamRelease(stream);
That is quite error-prone and tedious. So I want to write a wrapper class, but don't have any idea on when or where to release the Ref. Is it correct to do 'free' in dealloc?
I have not upgraded to Ventura yet. Yesterday one of my user (of one of my apps) mentioned that he has no Python environment on Ventura. Is it true?
Xcode 14.2 is really crap.
I cannot find the Preview function as what I have in previous version. I cannot find this menu item:
I am in peril. Can anyone save me. I am desperate!
I am using Xcode Version 14.2 (14C18). I created a fresh new library project (plain C/C++) and added the well-known SQLite3.h and SQLite3.c.
When I build debug configuration, Xcode correctly produces dylib. But when I do archive build, the generated xcarchive is almost empty - it does not have expected libsqlite3s.dylib!
I even went back to Xcode 7.2.1 on macOS 10.10. Xcode 7.2.1 can correctly produce archived dylib and I can link the dylib with a test app.
I am extremely frustrated!
I am in peril. Can anyone save me. I am desperate!
I am using Xcode Version 14.2 (14C18) to build my 2 dylibs. I had no problems with older versions of Xcode (one and half a year ago). But it's causing code signing problems and Connect fails my submitted binary package complaining I had wrong entitlement on dylibs.
I contact Apple technical support and I got a reply:
Entitlements are only effective on a main executable. When you sign a shared library with entitlement then, at best, the system ignores them. However, in some cases you can run into mysterious problems like this one.
The key problem is that Xcode is autogenerating entitlement file for my dylibs. I have no entitlement files in my projects, I am sure.
codesign -d --ent - libsqlite3s.dylib
Executable=/Users/USERNAME/Library/Developer/Xcode/DerivedData/libsqlite3s-ahztenmeyvsijneqjzdtifjhljlr/Build/Products/Debug/libsqlite3s.dylib
[Dict]
[Key] com.apple.application-identifier
[Value]
[String] TEAMID.net.neolib.libsqlite3s
How can I turn off this 'useful' feature?