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SwiftLee Weekly by Antoine van der Lee

SwiftLee Weekly - Issue 272

Published 26 days ago • 5 min read

This week's SwiftLee Weekly covers:

  • Default Isolation in Swift 6.2
  • The .ignoredByLayout() modifier in SwiftUI
  • Optimizing Mathematical Computations in Swift

Enjoy this week's SwiftLee Weekly!

THIS WEEK'S BLOG POST

​Institutional Purchases: Understanding and Detecting​

Recently, I discovered a spike in total downloads of 25K installs. Yet, I did not see an unusual spike in trials or purchases. I decided to dive in and found out it was caused by something called Institutional Purchases.

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WWDC

​RocketSim Meetup at CommunityKit​

WWDC is happening soon! CommunityKit is a fantastic initiative by a group of friends from the Swift Community. They've opened up the doors for several events to take place in their venue near Apple Park for several events, and I'm happy to announce that I'll be hosting a RocketSim Meetup!

Are you around during WWDC and interested in RocketSim?
​Register for the event →

CURATED FROM THE COMMUNITY

​Default isolation with Swift 6.2​

Swift Concurrency is changing, and a significant change in Swift 6.2 will be the option to configure the default isolation.
​massicotte.org​

​Demystifying SwiftUI’s .ignoredByLayout() — How to Apply Geometry Effects Without Breaking Your Layout​

I wasn't aware of this modifier, but after reading this article and watching the videos, I'm pretty sure there will soon be a day that I'm happy to have read this article!
​fatbobman.com​

​Optimized mathematical computations in Swift​

Using sum(…) works fine in most cases, but what if you have thousands of values to sum? Luckily, there’s a great alternative that doesn’t need a lot of code rewrites.
​swiftwithmajid.com​

​SwiftUI Picker With Optional Selection​

I’ve been struggling to make this work quite a few times for RocketSim and had no clue there was an official way to provide an optional selection inside a SwiftUI picker. This is a must-read!
​useyourloaf.com​

​Testing Remote Push Notifications with iOS Simulators​

There are several ways to test push notifications, all with their benefits. This article demonstrates three different ways of testing inside Xcode’s Simulator.
​tiagohenriques.dev​

SWIFT EVOLUTION

An overview of last week's Swift Proposal state changes. Check them out when they're in review, as it's your opportunity to influence the direction of Swift's future.

CODE SNIPPET OF THE WEEK

Constant Binding in SwiftUI

You can find this post on Twitter/X, LinkedIn, or Bluesky.

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Antoine v.d. SwiftLee 
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@twannl
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QUESTION OF THE WEEK

“
Is there a Combine alternative using Swift Concurrency?

Combine has not received many updates over the past years and it seems that Apple is slowly moving away from it too with the introduction of @Observable. Yet, there has not been an obvious replacement to observe values as we know from Combine.

There are ways to use AsyncStream to create a similar pipeline, but it comes with limitations like having only a single subscriber.

​Apple's open-sourced Async Algorithms framework comes with methods you'll recognize from Combine pipelines, but it's the AsyncExtensions package that will give you classes like AsyncPassthroughSubject which will be closer to what you use in Combine.

I also want to highlight Swift Evolution Proposal SE-475: Transactional Observation of Values which is currently in Active Review. It's not a Combine replacement, but it will be a useful tool in case it gets implemented into a future version of Swift.

Finally, I've not found myself using Combine pipelines a lot lately. Debouncing and throtthling can be done via Swift Concurrency (learn about it here) and observing values is something I do using SwiftUI bindings. Whether these use Combine under the hood or not: I'll let Apple decide and make my code future proof.

Want to have your question answered next week? Ask your question via this form (anonymously) or reply to this email with your question.

EARN ROCKETSIM LIFETIME

Share and Earn RocketSim Lifetime & a 1-on-1 coaching session

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How to get started:

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Thank you so much for your support, and until next Tuesday,

Antoine

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SwiftLee Weekly by Antoine van der Lee

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