Hi, my name is Donny

Sometimes when you’re programming you have some properties that are pretty expensive to compute so you want to make sure that you don’t perform any work that you don’t absolutely must perform. For example, you might have the following two criteria for your property: The property should be computed once The property should be computed only when I need it If these two criteria sound like what you’re looking for, then lazy vars are for you. A lazy variable is...

Swift offers multiple ways to iterate over a collection of items. In this post we’ll compare a normal for loop to calling forEach on a collection. Both for x in collection and collection.forEach { x in } allow you to iterate over elements in a collection called collection. But what are their differences? Does one outperform the other? Is one better than the other? We’ll find out in this post. Using a regular for loop I’ve written about for loops...

Swift 5.5 introduced loads of new concurrency related features. One of these features is the MainActor annotation that we can apply to classes, functions, and properties. In this post you’ll learn several techniques that you can use to dispatch your code to the main thread from within Swift Concurrency’s tasks or by applying the main actor annotation. If you’d like to take a deep dive into learning how you can figure out whether your code runs on the main actor...

If you’re keen on reading about what’s new in Swift or learn about all the cool things that are coming up, you’re probably following several folks in the iOS community that keep track and tell you about all the new things. But what if you read about an upcoming Swift feature that you’d like to try out? Do you have to wait for it to become available in a new Xcode release? Sometimes the answer is Yes, you’ll have to...

When you start learning about actors in Swift, you’ll find that explanations will always contain something along the lines of “Actors protect shared mutable state by making sure the actor only does one thing at a time”. As a single sentence summary of actors, this is great but it misses an important nuance. While it’s true that actors do only one thing at a time, they don’t always execute function calls atomically. In this post, we’ll explore the following: Exploring...

On of app development’s largest downsides (in my opinion) is that it’s frustratingly hard for developers to quickly iterate on an app’s core features due to the App Review process which can take anywhere between a few hours to a few days. As a result of this process, developers either need to ship their apps with A/B testing built in if they want to test multiple variations of a feature, they can iterate more slowly or they can opt to...