#PropertyWrapper
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paulio87.bsky.social
Exploring a Call Once property wrapper in Swift using parameter packs.

paul-samuels.com/blog/2026/01...

#swift #propertyWrapper #parameterPacks
Call Once · paul-samuels.com
paul-samuels.com
January 30, 2026 at 2:18 AM
corneliusmark.bsky.social
Yes.
Line 2 creates an NSFetchRequest. Don't confuse this with the FetchRequest propertywrapper.
Line 3 to 5 sets the properties needed for the NSFetchRequest.
Line 8 inserts the first SectionEntity found into the RecordListView.
Line 9 inserts the viewContext into the Environment of subviews.
April 15, 2025 at 8:05 AM
fcanas.bsky.social
Swift property observers work on most variable declarations. This only helps if you want to watch variables and you're open to recompiling.

Property wrappers work on any variable that isn't top-level code.

In neither case does the "property" need to be a property of a class, struct, or enum.
Swift code demonstrating the use of the "willSet" property observer and the definition of an "Incrementing" property wrapper. The code sample is not a complete program, but the contents of the image are listed completely as follows: ``` var counter: Int = 0 { willSet { assert ( newValue >= counter ) } } @propertyWrapper struct Incrementing<V> where V: Comparable { var wrappedValue: V { willSet { assert ( newValue >= wrappedValue ) } } } func t() { @Incrementing var anotherCounter: Int = 0 ```
December 20, 2024 at 8:28 PM
krzyzanowskim.com
Stop Me Here. propertyWrapper Alert!!! I have the urde to write a propertyWrapper for a single property.
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no, really, it's overkill, and justified only for an educational purpose.
February 5, 2025 at 12:29 AM
krzyzanowskim.com
Controversial opinion: Xcode should have propertyWrapper snippet build in by 2021 or later.
February 5, 2025 at 12:23 AM
krzyzanowskim.com
@ frozen @ propertyWrapper @ dynamicMemberLookup public struct Foo {}
January 10, 2025 at 7:10 PM
swiftpackageupdates.mas.to.ap.brid.gy
📦 Simon Whitty just added a new package, Awaiting – Swift @propertyWrapper that waits asynchronously until the value matches a predicate.

https://swiftpackageindex.com/swhitty/Awaiting
February 11, 2025 at 10:36 AM
treastrain.jp
Apple のサンプルコードに含まれている これにインスパイアされています x.com/treastrain/s...
treastrain / Tanaka.R on X: "特に ExposureNotificationApp/Model/LocalStore.swift の @propertyWrapper で Persisted<Value: Codable> を作って、store する各パラメータに @Persisted をつけている書き方、簡単だし見やすいしめっちゃいい… 今すぐにでも導入したい……！ https://t.co/aqA2RgzjZc" / X
特に ExposureNotificationApp/Model/LocalStore.swift の @propertyWrapper で Persisted<Value: Codable> を作って、store する各パラメータに @Persisted をつけている書き方、簡単だし見やすいしめっちゃいい… 今すぐにでも導入したい……！ https://t.co/aqA2RgzjZc
x.com
May 8, 2025 at 8:43 PM
treastrain.jp
今なら RemoteConfigValueObservable を Swift 5.9 の Observable にできそう　contribute chance

firebase-ios-sdk/FirebaseRemoteConfigSwift/Sources/PropertyWrapper/RemoteConfigValueObservable.swift at 10.15.0 · firebase/firebase-ios-sdk github.com/firebase/fir...
firebase-ios-sdk/FirebaseRemoteConfigSwift/Sources/PropertyWrapper/RemoteConfigValueObservable.swift...
Firebase SDK for Apple App Development. Contribute to firebase/firebase-ios-sdk development by creating an account on GitHub.
github.com
September 23, 2023 at 4:54 PM
gaipoi.bsky.social
SwiftUIで作られたViewはOSから再レンダリングを要求されたらそれに応えねばならないので、例えばObservableなPropertyWrapperを持つViewModelを持っていても、そのinitの中で何かしらの処理を呼び出すのはナンセンスでonAppearなどのライフサイクルの中でコールすることで呼び出し回数を制御しなければならない。
March 17, 2025 at 1:33 PM
gaipoi.bsky.social
SwiftUI、struct(= value type)で実装するのでclass(= reference type)のようにPropertyWrapperで定義されている以外の内部変数を更新できず、宣言的な実装が至る所で求められる。ゆえに複雑なViewの状態も宣言的に実装しないといけないのでデータ構造きちんとしないと逆にしんどくなる感じがある
December 6, 2024 at 2:18 PM
gaipoi.bsky.social
GestureStateなるPropertyWrapperが存在していることもこのAppleのドキュメント見るまで知らなかった。わざわざそれ用のPropertyWrapperを自作していたのにOSレベルで標準提供されているのね...
developer.apple.com/documentatio...
LongPressGesture | Apple Developer Documentation
A gesture that succeeds when the user performs a long press.
developer.apple.com
December 6, 2024 at 2:06 PM
gaipoi.bsky.social
昨今のSwift(特にSwift5でPropertyWrapperが追加されたあたりから)言語自体の機能も出来ることも増えすぎて何も選定できないような状態になってる笑
August 10, 2024 at 9:58 AM
0xwdg.bsky.social
Is there anyone who can help me with #SwiftUI #PropertyWrapper and #DynamicProperty it is not working as I expect it to work, https://forums.swift.org/t/dynamicproperty-propertywrapper-is-not-working-as-i-expect-it-to-work/78422 #swift #swiftlang
DynamicProperty PropertyWrapper is not working as I expect it to work - Using Swift - Swift Forums
Hi All. I have a question why a Dynamic Property wrapper is not working as I expect it to work. If I do this with @AppStorage it works as expected, but with @iCloudStorage it does not work. Demo code with @AppStorage: class DataClass: ObservableObject { @AppStorage("dataSource") var dataSource: String = "DataSource" } struct ContentView: View { @ObservedObject var data = DataClass() var body: some View { VStack { Text(data.dataSource) // this does update...
forums.swift.org
March 10, 2025 at 11:28 PM
sabaleuski.bsky.social
PropertyWrappers were a good feature, but they totally break Swift6 compatibility in their current form. If you have any field with propertyWrapper in your class, you can’t make it Sendable
November 20, 2024 at 5:39 PM