Advanced Swift

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Why opaque return types are so important

12:19

Why opaque return types are so important

Opaque return types are a powerful feature in Swift, and are also critically important for writing SwiftUI. In this article I’ll be explaining how they work, and why they give us more power than returning a simple protocol.

The pros and cons of operator overloading

23:37

The pros and cons of operator overloading

I’ve written about operator overloading previously, not least in my book Pro Swift, but in the article I want to go into more depth on the places where it’s really useful – and the places where it’s not such a good idea.

Making the most of optionals

23:07

Making the most of optionals

Swift’s optionals are implemented as simple enums, with just a little compiler magic sprinkled around as syntactic sugar. However, they do much more than people realize, and in this article I’m going to demonstrate some of their power features that can really help you write better code – and blow your mind along the way.

Making the most of optionals – part 2

20:24

Making the most of optionals – part 2

I already introduced how the internals of optionals work, including how they use conditional conformance and how to avoid infinitely sized structs. In this video I’m going to go further as we look at how our knowledge of Optional can be translated to Result, why it’s so important that optionals are functors and monads, and more.

How to use phantom types in Swift

24:11

How to use phantom types in Swift

Phantom types are a powerful way to give the Swift compiler extra information about our code so that it can stop us from making mistakes. In this article I’m going to explain how they work and why you’d want them, as well as providing lots of hands-on examples you can try.

Existentials and type erasure – part 1

17:14

Existentials and type erasure – part 1

Type erasure helps us solve difficult type system problems by purposefully discarding some information. In this article we’ll look at what the underlying problem is and how Swift solves it, and in the second part we’ll continue on to look at how we can build type erasure ourselves.

Existentials and type erasure – part 2

41:03

Existentials and type erasure – part 2

In the first part of this tutorial we looked at the underlying problem that type erasure is trying to solve, and tried out Swift’s approach using AnySequence. In this second part we’re going to adapt Swift’s own solution to get real type erasure for our own code.

Advanced string interpolation, part one

24:23

Advanced string interpolation, part one

String interpolation is easy, right? Wrong! String interpolation is actually a huge power feature in Swift, and we have a massive array of functionality on hand to help us customize it. In this article I’ll show you just how much control we have, and how to use that control to make your code easier to read.

Advanced string interpolation, part two

19:32

Advanced string interpolation, part two

In part one of this tutorial we looked at how to customize string interpolations on a type-by-type basis, giving you more control over how your code works. In this second part we’ll look at a second powerful use for interpolation: building whole types from scratch.