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Share Swift Code between Swift On Server Vapor and Client App

Sharing Swift code between a backend and client app is one of the benefits you'll get when working with Swift on a Server. You can create dedicated Swift Packages containing sharable logic for both client and backend. While many developers mention sharing Swift code as one of the benefits of ...

Ranges in Swift explained with code examples

Ranges in Swift allow us to select parts of Strings, collections, and other types. They're the Swift variant of NSRange which we know from Objective-C, although they're different in usage, as I'll explain in this blog post. Ranges allow us to write elegant Swift code by using the range operator ...

MainActor usage in Swift explained to dispatch to the main thread

MainActor is a new attribute introduced in Swift 5.5 as a global actor providing an executor which performs its tasks on the main thread. When building apps, it's essential to perform UI updating tasks on the main thread, which can sometimes be challenging when using several background threads. Using the ...

Optimizing your app for Network Reachability

Network Reachability is a vital aspect of apps that use some networking capabilities. Your users won't always have a good internet connection, so optimizing your app for bad networking conditions is essential. We can leverage several techniques to optimize our app accordingly, but it's essential to be aware of common ...

The operation couldn’t be completed: solving errors in Swift

"The operation couldn't be completed" is a common error to receive from Apple's standard SDKs or 3rd party libraries. The errors often come with an error code that doesn't have a description, leaving you behind with unclear directions on solving the issue. I've been running into these errors quite often, ...

Equatable conformance in Swift explained with code examples

Equatable conformance allows you to compare one object with another. Based on whether the objects match, you can perform a specific operation. You can rely on default comparison implementations or custom logic to compare two objects. Many standard types are already comparable, but you must implement protocol conformance for your ...

Detached Tasks in Swift explained with code examples

Detached tasks allow you to create a new top-level task and disconnect from the current structured concurrency context. You could argue that using them results in unstructured concurrency since you're disconnecting potentially relevant tasks. While it sounds terrible to disconnect from structured concurrency, there are still examples of use cases ...

Task Groups in Swift explained with code examples

Task Groups in Swift allow you to combine multiple parallel tasks and wait for the result to return when all tasks are finished. They are commonly used for tasks like combining multiple API request responses into a single response object. Read my article about tasks first if you're new to ...

Enum explained in-depth with code examples in Swift

Enum usage in Swift: If case, guard case, fallthrough, and the CaseIteratable protocol. These are all terms which could sound familiar if you've worked a lot with enums in Swift. An enumeration defines a common type for a group of related values and enables you to work with those values ...

OptionSet in Swift explained with code examples

OptionSet in Swift allows you to define a set of options for configurations. It's the Swift variant of the well-known NS_OPTIONS in Objective-C and it's used throughout the standard libraries. A set of options is often confused by a set of enum cases, but they're not the same. While you ...

@dynamicCallable in Swift explained with code examples

It's all in the name: @dynamicCallable in Swift allows you to dynamically call methods using an alternative syntax. While it's primarily syntactic sugar, it can be good to know why it exists and how it can be used. We covered @dynamicMemberLookup earlier, allowing us to express member lookup rules in ...

Binary Targets in Swift Package Manager

Binary Targets in Swift Package Manager (SPM) allow packages to declare xcframework bundles as available targets. The technique is often used to provide access to closed-source libraries and can improve CI performance by reducing time spent on fetching SPM repositories. Both downs and upsides are essential to consider when adding ...