2 min read

Issue #27

Hi there,

It's getting harder and harder to not share cool things from iOS 16 (that we can't yet use). I'm managing to resist so far. Hope you find something interesting and useful in today's collection!

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Using unsafe pointers safely

Unsafe pointers and bytes are only "safe" to use inside the body closure. From withUnsafeMutablePointer documentation: The pointer argument is valid only for the duration of the function’s execution.

DRY, evolved

Check out this thread about SPOT - Single Point Of Truth principle. It's similar to DRY (Don't Repeat Yourself), but better. I've been looking at code this way as long as I remember - I had no idea this way of thinking had its own name.

This comment perfectly points out the difference between SPOT and DRY:

Beautiful rounded corners

Are you using cornerRadius for rounding corners? There's a better way - .clipShape as a RoundedRectangle with continuous style in SwiftUI produces a smoother looking result. To achieve the same in UIKit, do button.layer.cornerCurve = .continuous .

Check this thread for comparison and SwiftUI code:


In issue #21 I shared an article about CloudKit being a red flag for indie developers. The biggest issue named was the inability to transfer the app to another developer account, if a CloudKit entitlement was ever used in the app.

That restriction is now gone - now apps that use iCloud can be transferred to another developer account 🎉

Here's the updated list of criteria for app transfer: App Transfer Criteria

App Store Connect Update - Releases - Apple Developer

Apps that use iCloud can now be transferred to another developer in the Apple Developer Program.

Non-optional Core Data attributes in Swift

There is a distinction between the concept of optional and non-optional values in Swift and Core Data. In Swift, you get compile-time guarantees, but in Core Data, the framework is enforcing the model rules in run-time. Optional Core Data attributes should be optional properties in Swift, but what about non-optional attributes?

In this article Jesse shares a robust approach to handling the differences and making sure the app doesn't crash.

How to more gracefully handle non-optional Core Data properties in Swift · Jesse Squires


Alright, that’s it for today.

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