The Swift website provides nightly builds of the Swift compiler (called toolchains) for download. Building with a nightly compiler can be useful if you want to check if a bug has already been fixed on main, or if you want to experiment with upcoming language features such as Embedded Swift, as I’ve been doing lately. A toolchain is distributed as a .pkg installer that installs itself into /Library/Developer/Toolchains (or the equivalent path in your home directory). After installation, you have several options to select the toolchain you want to build with: In Xcode In Xcode, select the toolch ..read more

You may have noticed that the Swift compiler automatically treats the closure of a DispatchQueue.main.async call as @MainActor. In other words, we can call a main-actor-isolated function in the closure: import Dispatch @MainActor func mainActorFunc() { } DispatchQueue.main.async { // The compiler lets us call this because // it knows we're on the main actor. mainActorFunc() } This behavior is welcome and very convenient, but it bugs me that it’s so hidden. As far as I know it isn’t documented, and neither Xcode nor any other editor/IDE I’ve used do a good job of showing me the ..read more

Problem The Photos app on macOS doesn’t provide a keyboard shortcut for the Export Unmodified Original command. macOS allows you to add your own app-specific keyboard shortcuts via System Settings > Keyboard > Keyboard Shortcuts > App Shortcuts. You need to enter the exact spelling of the menu item you want to invoke. Photos renames the command depending on what’s selected: Export Unmodified Original For 1 Photo“ turns into ”… Originals For 2 Videos” turns into “… For 3 Items” (for mixed selections), and so on. Argh! The System Settings UI for assigning keyboard shortcuts is extremel ..read more

I rarely participate actively in the Swift Evolution process, but I frequently refer to evolution proposals for my work, often multiple times per week. The proposals aren’t always easy to read, but they’re the most comprehensive (and sometimes only) documentation we have for many Swift features. For years, my tool of choice for searching Swift Evolution proposals has been Karoy Lorentey’s swift-evolution workflow for Alfred. The workflow broke recently due to data format changes. Karoy was kind enough to add me as a maintainer so I could fix it. The new version 2.1.0 is now available on GitHu ..read more

Foundation overloads the pattern matching operator ~= to enable matching against error codes in catch clauses. catch clauses in Swift support pattern matching, using the same patterns you’d use in a case clause inside a switch or in an if case … statement. For example, to handle a file-not-found error you might write: import Foundation do { let fileURL = URL(filePath: "/abc") // non-existent file let data = try Data(contentsOf: fileURL) } catch let error as CocoaError where error.code == .fileReadNoSuchFile { print("File doesn't exist") } catch { print("Other error: \(error ..read more

I know I’m almost a decade late to this party, but I’m probably not the only one, so here goes. Double Fine Adventure was a wildly successful 2012 Kickstarter project to crowdfund the development of a point-and-click adventure game and, crucially, to document its development on video. The resulting game Broken Age was eventually released in two parts in 2014 and 2015. Broken Age is a beautiful game and I recommend you try it. It’s available for lots of platforms and is pretty cheap (10–15 euros/dollars or less). I played it on the Nintendo Switch, which worked very well. Broken Age. But the r ..read more

And what it can teach us about SwiftUI’s stack layout algorithm I have one more thing to say on the relative sizing view modifier from my previous post, Working with percentages in SwiftUI layout. I’m assuming you’ve read that article. The following is good to know if you want to use the modifier in your own code, but I hope you’ll also learn some general tidbits about SwiftUI’s layout algorithm for HStacks and VStacks. Using relative sizing inside a stack view Let’s apply the relativeProposed modifier to one of the subviews of an HStack: HStack(spacing: 10) { Color.blue .relativ ..read more

SwiftUI’s layout primitives generally don’t provide relative sizing options, e.g. “make this view 50 % of the width of its container”. Let’s build our own! Use case: chat bubbles Consider this chat conversation view as an example of what I want to build. The chat bubbles always remain 80 % as wide as their container as the view is resized: The chat bubbles should become 80 % as wide as their container. Download video Building a proportional sizing modifier 1. The Layout We can build our own relative sizing modifier on top of the Layout protocol. The layout multiplies its own proposed size (whi ..read more

Problem The Photos app on macOS doesn’t provide a keyboard shortcut for the Export Unmodified Original command. macOS allows you to add your own app-specific keyboard shortcuts via System Settings > Keyboard > Keyboard Shortcuts > App Shortcuts. You need to enter the exact spelling of the menu item you want to invoke. Photos renames the command depending on what’s selected: Export Unmodified Original For 1 Photo“ turns into ”… Originals For 2 Videos” turns into “… For 3 Items” (for mixed selections), and so on. Argh! The System Settings UI for assigning keyboard shortcuts is extremel ..read more

I rarely participate actively in the Swift Evolution process, but I frequently refer to evolution proposals for my work, often multiple times per week. The proposals aren’t always easy to read, but they’re the most comprehensive (and sometimes only) documentation we have for many Swift features. For years, my tool of choice for searching Swift Evolution proposals has been Karoy Lorentey’s swift-evolution workflow for Alfred. The workflow broke recently due to data format changes. Karoy was kind enough to add me as a maintainer so I could fix it. The new version 2.1.0 is now available on GitHu ..read more