— Turing complete with a stack of 0xdeadbeef



Failable initializers, revisited

Functional approaches to avoid Swift's failable initializers

In a previous post, I discussed how Swift’s failable initializers could be problematic. Specifically, I argued that their ease of use could persuade or encourage us to revert to old (bad) Objective-C habits of returning nil from init. Initialization is usually not the right place to fail. We should aim to avoid optionals as much as possible to reduce having to handle this absence of values. Recently, @danielgomezrico asked a great question about a possible use case for a failable initializer — parsing JSON. Given this problem’s popularity in the Swift community, I thought sharing my response here would be helpful.

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Functional notifications

Exploring the flexibility of Swift micro-libraries

The observer pattern is a powerful way to decouple the sending and handling of events between objects in a system. On iOS, one implementation of this pattern is via NSNotificationCenter. However, the NSNotificationCenter APIs are kind of cumbersome to use and require some boilerplate code. Luckily, Swift gives us the tools to improve NSNotificationCenter with very little code.

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Better Core Data models in Swift

How Swift can bring clarity and safety to your managed objects

As I continue my work with Core Data and Swift, I have been trying to find ways to make Core Data better. Among my goals are clarity and safety, specifically regarding types. Luckily, we can harness Swift’s optionals, enums, and other features to make managed objects more robust and more clear. But even with the improvements that Swift brings, there are still some drawbacks and limitations with Xcode’s current toolset.

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