Swift by Sundell - Swift by Sundell Newsletter #24

👋 Hi everyone

July brought two quite significant changes to Swift by Sundell. First, the podcast has a new, tweaked format, with slightly shorter episodes each focused on a single main topic. Second, the podcast’s Q&A section has now been moved to the website instead — where I’m able to answer the community’s most commonly asked questions in much more depth and detail, along with code samples and more, all of which can then be searched and linked to with ease.

I’m continuing to tweak my work to try to provide as much value to the Swift community as I possibly can. Hope you’ll enjoy these changes, and like always, just can simply reply to this email if you want to send me any feedback. But now, here’s your summary of everything that was published on Swift by Sundell during the month of July.

📖 Weekly articles

For 180 weeks, I’ve been publishing a new article about Swift every Sunday. These articles were added during the past month:

A guide to SwiftUI’s state management system

Let’s take a closer look at each of SwiftUI’s state handling property wrappers, how they relate to each other, and how they make up different parts of SwiftUI’s overall state management system.

Opaque return types in Swift

An in-depth look at opaque return types, how they can be used both with and without SwiftUI, and how they compare to similar generic programming techniques, such as type erasure.

Five powerful, yet lesser-known ways to use Swift enums

An overview of a few somewhat lesser-known ways in which enums can be used to solve various problems in Swift-based apps and libraries.

Building custom Combine publishers in Swift

What goes into building a custom Combine publisher, and what sort of situations that might require us to do that.

🎧 Podcast episodes

The Swift by Sundell podcast is a bi-weekly show featuring special guests from all around the Swift community. You can find it in your podcast player of choice, for example Apple Podcasts or Overcast. These episodes were published during the past month:

77: “Adopting new system features”, with Jordan Morgan

Jordan Morgan joined me to discuss various strategies for adopting new system features and APIs, how to keep up with the rapid changes to iOS, macOS and Apple’s other platforms, and how to allocate time between different projects.

78: “What’s new in Swift 5.3”, with JP Simard

JP Simard returned to the show to discuss Swift 5.3’s main new features and improvements, and what those changes might tell us about the current state of Swift and its evolution process.

✅ Basics

With the Basics series, my goal is to build up a comprehensive library of articles that cover most of the core aspects of Swift and iOS development. This article was published during the past month:

Type inference

An introduction to Swift’s type inference system, how it makes the syntax of the language so lightweight, and how to work around some of its limitations.

⁉️ Questions & Answers

Answers to common questions about Swift development, or about my work in general. These are the questions that I answered during the past month:

How can a SwiftUI Text with mixed styling be created?

SwiftUI does not (yet) have a built-in equivalent to NSAttributedString, so how can we style various parts of a text differently when building UIs using it?

How to pick between using a struct or a class?

Not just a question of value types versus reference types.

Why can’t certain protocols, like Equatable and Hashable, be referenced directly?

A few tips for working with generic protocols.

Is using [weak self] always required when working with closures?

Capturing self does not always cause a retain cycle, but it could, so here are a few guidelines that can be good to keep in mind when working with closures.

What’s my workflow for writing and publishing articles?

How I decide what topics to write about, and what my workflow looks like when writing and editing an article.

How to create an array with mixed types in Swift?

Multiple techniques for storing values of mixed types within a Swift array.

⭐️ Swift tips

I love to share shorter tips, tricks and techniques with the community. These are the tips that I shared during the past month:

Using an AppDelegate with the new SwiftUI-based app lifecycle

How to bridge the UIKit way of managing an app’s lifecycle with SwiftUI’s new App API.

Implicit capturing of self in Swift 5.3

How Swift now enables us to omit self when accessing a method or property within certain escaping closures.

SwiftUI extensions using generic type constraints

Creating specialized SwiftUI convenience APIs using generics.

Generating automatic placeholders for SwiftUI views

A short guide to SwiftUI’s new redacted modifier.

Adding SwiftUI’s ViewBuilder attribute to functions

How custom functions can be annotated with @ViewBuilder to enable us to make full use of SwiftUI’s DSL within such functions.

😊 Until next time

That’s it for this edition! I hope you enjoyed this newsletter. I always love to hear your feedback, so feel free to either reply to this email, or contact me on Twitter @johnsundell. I read every single piece of feedback that I get, and I try to reply to as many people as I possibly can.

Thanks for reading! 🚀

- John