Working on @pointfreeco and @isowords. 🦋 @stephencelis.com 🐘 @stephencelis@hachyderm.io
California
Joined June 2007
- Tweets9.9K
- Following340
- Followers5.4K
- Likes8K
Stephen Celis retweeted
Introducing: CompilationTesting!
Test code that should produce Swift errors, warnings, fix-its, and notes.
pointfree.co/blog/posts/234-…
Stephen Celis retweeted
Did you know Swift actors can share the same isolation and communicate with one another in a completely synchronous manner?
This week we apply the idea to ComposableArchitecture 2.0, where a scoped StoreActor can wrap a parent and share parts of the same core domain and state.
ALT A Swift test: @Test func `store actor scoping`() async throws { let store = await StoreActor( initialState: Counter.State(), feature: Counter() ) let childStore = await store.scope(\.count) await childStore.send(.incrementButtonTapped) await #expect(store.state.count == 1) }
Stephen Celis retweeted
This week we conclude our series by showing how to share isolation across boundaries!
By abstracting our nonisolated core with a protocol, isolated shells can scope down to subfeatures while retaining all the benefits of controlled isolation.
pointfree.co/episodes/ep384-…
Stephen Celis retweeted
This week we started reaping the benefits of "nonisolated core, isolated shell". We write features a single time, without thinking about isolation, then wrap the feature in the isolation we need. @MainActor for SwiftUI, arbitrary actor for tests!
pointfree.co/collections/bey…
Stephen Celis retweeted
The feedback on ComposableArchitecture 2.0 has been pretty reassuring 😁
ALT A screen shot from Slack: i recently started using TCA 2.0 in a large codebase with mutliple architectures and old technologies was able to refactor an old module and went from 70K lines of code down to 13K :exploding_head: and the best part? it was better in ALL aspects: performance, efficiency, developer experience, and smooth UI and UX AND was testable in every single aspect one can think of. thank you @Brandon Williams and @Stephen Celis for the incredible work and effort! :sparkles::fire:
Stephen Celis retweeted
Advanced Swift macro technique: Accessing inferred types
Macros only see the syntax of Swift code, so it seems impossible to access inferred types. But with a clever trick involving associated type inference, we can achieve the seemingly impossible!
pointfree.co/blog/posts/233-…
Stephen Celis retweeted
Which error would you prefer to diagnose? The one that is presented on the problematic line, or the one hidden in the guts of expanded macro code?
Part 1 of our Advanced Swift Macros series is out!
You may think macros can only see the stringy syntax of Swift code, but it is possible to tease out some static type information. You can even detect if a type conforms to a protocol!
🤯 pointfree.co/blog/posts/232-…
Stephen Celis retweeted
Part 1 of our Advanced Swift Macros series is out!
You may think macros can only see the stringy syntax of Swift code, but it is possible to tease out some static type information. You can even detect if a type conforms to a protocol!
🤯 pointfree.co/blog/posts/232-…
Stephen Celis retweeted
Come for the real world explanations of isolation in Swift, stay for the deep dives into esoteric underscored attributes like '@_inheritActorContext(always)' 🤣
pointfree.co/collections/bey…
Stephen Celis retweeted
This week we explore the “Nonisolated Core, Isolated Shell” pattern in Swift using a type that drives the business logic of a SwiftUI app.
A nonisolated “Core” type is hosted in an isolated “Store” type, simplifying the complexities one typically encounters in Swift concurrency.
ALT A code snippet from the episode of the “Core” type.
ALT A code snippet from the episode of the “Store” type.
“Nonisolated Core, Isolated Shell” is our mantra for wielding Swift concurrency effectively, with minimal suspension points and locking, and maximal reliability and testability.
Modern concurrency tools like nonisolated(nonsending) and Task.immediate got us closer to our goal, but not all the way. So we’re trying a new approach inspired by Gary Bernhardt’s “functional core, imperative shell”:
Nonisolated core, isolated shell.
pointfree.co/episodes/ep382-…
Stephen Celis retweeted
Modern concurrency tools like nonisolated(nonsending) and Task.immediate got us closer to our goal, but not all the way. So we’re trying a new approach inspired by Gary Bernhardt’s “functional core, imperative shell”:
Nonisolated core, isolated shell.
pointfree.co/episodes/ep382-…
If you’re interested in writing async code that is easy and reliable to test, and free of UI glitches from thread hops, nonisolated(nonsending) and Task.immediate can get you there!
We tried using two modern Swift concurrency tools to allow us to embrace non-sendability:
• nonisolated(nonsending)
• Task.immediate
They got us close to our goals, but sadly there were still data races. Watch this week's episode to understand why:
pointfree.co/episodes/ep381-…
Stephen Celis retweeted
We tried using two modern Swift concurrency tools to allow us to embrace non-sendability:
• nonisolated(nonsending)
• Task.immediate
They got us close to our goals, but sadly there were still data races. Watch this week's episode to understand why:
pointfree.co/episodes/ep381-…
Stephen Celis retweeted
Our deep dive into Swift isolation from a few months back may have been a bit abstract for people, so we are bringing things down to earth by designing real world code with isolation in mind from the beginning:
pointfree.co/collections/bey…
Stephen Celis retweeted
Our code is at an impasse: we want to embrace non-sendability, but async work seems to force us into Sendable. We’ll revisit our approach to this problem from ComposableArchitecture 1.0, see why it's not ideal, and search for a better way.
pointfree.co/episodes/ep381-…
Stephen Celis retweeted
It’s time to put what we’ve learned about isolation into practice. We’re building the reimagined Composable Architecture 'Store' from scratch and exploring the benefits of strictly controlling isolation through every layer of the library.
pointfree.co/episodes/ep380-…
Stephen Celis retweeted
Earlier this week we held our first Point-Free Office Hour. We answered questions from our viewers and gave a tiny preview of a new library we are working on.
Check it out:
pointfree.co/office-hours/f6…
Stephen Celis retweeted
For the past 10 weeks we have analyzed many of the new SwiftUI and SwiftData features announced at WWDC26. We uncovered a lot of things that haven't gotten widespread attention in the community, and now the whole series is free!
👉 pointfree.co/blog/posts/226-…
Stephen Celis retweeted
Last month we shipped 40 releases across 16 of our open source libraries, including new JSON and DB collation tools, preview traits in Dependencies, and the completion of a years-long package rename. Here’s a recap of everything that happened.
pointfree.co/blog/posts/225-…
