Various improvements

Defaults.xcodeproj/project.pbxproj

@@ -33,14 +33,14 @@
 		E38C9F28244ADA2F00A6737A /* SwiftUI.swift in Sources */ = {isa = PBXBuildFile; fileRef = E38C9F26244ADA2F00A6737A /* SwiftUI.swift */; };
 		E38C9F29244ADA2F00A6737A /* SwiftUI.swift in Sources */ = {isa = PBXBuildFile; fileRef = E38C9F26244ADA2F00A6737A /* SwiftUI.swift */; };
 		E38C9F2A244ADA2F00A6737A /* SwiftUI.swift in Sources */ = {isa = PBXBuildFile; fileRef = E38C9F26244ADA2F00A6737A /* SwiftUI.swift */; };
-		E3EB3E33216505920033B089 /* util.swift in Sources */ = {isa = PBXBuildFile; fileRef = E3EB3E32216505920033B089 /* util.swift */; };
+		E3EB3E33216505920033B089 /* Utilities.swift in Sources */ = {isa = PBXBuildFile; fileRef = E3EB3E32216505920033B089 /* Utilities.swift */; };
 		E3EB3E35216507AE0033B089 /* Observation.swift in Sources */ = {isa = PBXBuildFile; fileRef = E3EB3E34216507AE0033B089 /* Observation.swift */; };
 		E3EB3E36216507B50033B089 /* Observation.swift in Sources */ = {isa = PBXBuildFile; fileRef = E3EB3E34216507AE0033B089 /* Observation.swift */; };
 		E3EB3E37216507B50033B089 /* Observation.swift in Sources */ = {isa = PBXBuildFile; fileRef = E3EB3E34216507AE0033B089 /* Observation.swift */; };
 		E3EB3E38216507B60033B089 /* Observation.swift in Sources */ = {isa = PBXBuildFile; fileRef = E3EB3E34216507AE0033B089 /* Observation.swift */; };
-		E3EB3E39216507C30033B089 /* util.swift in Sources */ = {isa = PBXBuildFile; fileRef = E3EB3E32216505920033B089 /* util.swift */; };
+		E3EB3E39216507C30033B089 /* Utilities.swift in Sources */ = {isa = PBXBuildFile; fileRef = E3EB3E32216505920033B089 /* Utilities.swift */; };
-		E3EB3E3A216507C40033B089 /* util.swift in Sources */ = {isa = PBXBuildFile; fileRef = E3EB3E32216505920033B089 /* util.swift */; };
+		E3EB3E3A216507C40033B089 /* Utilities.swift in Sources */ = {isa = PBXBuildFile; fileRef = E3EB3E32216505920033B089 /* Utilities.swift */; };
-		E3EB3E3B216507C40033B089 /* util.swift in Sources */ = {isa = PBXBuildFile; fileRef = E3EB3E32216505920033B089 /* util.swift */; };
+		E3EB3E3B216507C40033B089 /* Utilities.swift in Sources */ = {isa = PBXBuildFile; fileRef = E3EB3E32216505920033B089 /* Utilities.swift */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXContainerItemProxy section */
@@ -84,7 +84,7 @@
 		E339B3B22449ED2000E7A40A /* Reset.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; lineEnding = 0; path = Reset.swift; sourceTree = "<group>"; usesTabs = 1; };
 		E339B3B72449F10D00E7A40A /* UserDefaults.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; lineEnding = 0; path = UserDefaults.swift; sourceTree = "<group>"; usesTabs = 1; };
 		E38C9F26244ADA2F00A6737A /* SwiftUI.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; lineEnding = 0; path = SwiftUI.swift; sourceTree = "<group>"; usesTabs = 1; };
-		E3EB3E32216505920033B089 /* util.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; lineEnding = 0; path = util.swift; sourceTree = "<group>"; usesTabs = 1; };
+		E3EB3E32216505920033B089 /* Utilities.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; lineEnding = 0; path = Utilities.swift; sourceTree = "<group>"; usesTabs = 1; };
 		E3EB3E34216507AE0033B089 /* Observation.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; lineEnding = 0; path = Observation.swift; sourceTree = "<group>"; usesTabs = 1; };
 /* End PBXFileReference section */
 
@@ -221,7 +221,7 @@
 				E3EB3E34216507AE0033B089 /* Observation.swift */,
 				E286D0C623B8D51100570D1E /* Observation+Combine.swift */,
 				E38C9F26244ADA2F00A6737A /* SwiftUI.swift */,
-				E3EB3E32216505920033B089 /* util.swift */,
+				E3EB3E32216505920033B089 /* Utilities.swift */,
 			);
 			path = Defaults;
 			sourceTree = "<group>";
@@ -512,7 +512,7 @@
 				8933C7851EB5B820000D00A4 /* Defaults.swift in Sources */,
 				E339B3B92449F10D00E7A40A /* UserDefaults.swift in Sources */,
 				E3EB3E35216507AE0033B089 /* Observation.swift in Sources */,
-				E3EB3E33216505920033B089 /* util.swift in Sources */,
+				E3EB3E33216505920033B089 /* Utilities.swift in Sources */,
 				E339B3B42449ED2000E7A40A /* Reset.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
@@ -531,7 +531,7 @@
 			files = (
 				E286D0CA23B8D54E00570D1E /* Observation+Combine.swift in Sources */,
 				E38C9F2A244ADA2F00A6737A /* SwiftUI.swift in Sources */,
-				E3EB3E3A216507C40033B089 /* util.swift in Sources */,
+				E3EB3E3A216507C40033B089 /* Utilities.swift in Sources */,
 				E339B3BB2449F10D00E7A40A /* UserDefaults.swift in Sources */,
 				E3EB3E37216507B50033B089 /* Observation.swift in Sources */,
 				8933C7871EB5B820000D00A4 /* Defaults.swift in Sources */,
@@ -545,7 +545,7 @@
 			files = (
 				E286D0C923B8D54D00570D1E /* Observation+Combine.swift in Sources */,
 				E38C9F29244ADA2F00A6737A /* SwiftUI.swift in Sources */,
-				E3EB3E3B216507C40033B089 /* util.swift in Sources */,
+				E3EB3E3B216507C40033B089 /* Utilities.swift in Sources */,
 				E339B3BA2449F10D00E7A40A /* UserDefaults.swift in Sources */,
 				E3EB3E38216507B60033B089 /* Observation.swift in Sources */,
 				8933C7881EB5B820000D00A4 /* Defaults.swift in Sources */,
@@ -559,7 +559,7 @@
 			files = (
 				E286D0C723B8D51100570D1E /* Observation+Combine.swift in Sources */,
 				E38C9F27244ADA2F00A6737A /* SwiftUI.swift in Sources */,
-				E3EB3E39216507C30033B089 /* util.swift in Sources */,
+				E3EB3E39216507C30033B089 /* Utilities.swift in Sources */,
 				E339B3B82449F10D00E7A40A /* UserDefaults.swift in Sources */,
 				E3EB3E36216507B50033B089 /* Observation.swift in Sources */,
 				8933C7861EB5B820000D00A4 /* Defaults.swift in Sources */,

Sources/Defaults/Defaults.swift

@@ -1,7 +1,7 @@
 // MIT License © Sindre Sorhus
 import Foundation
 
-public protocol DefaultsBaseKey: Defaults.Keys {
+public protocol DefaultsBaseKey: Defaults.AnyKey {
 	var name: String { get }
 	var suite: UserDefaults { get }
 }
@@ -15,6 +15,7 @@ extension DefaultsBaseKey {
 
 public enum Defaults {
 	public typealias BaseKey = DefaultsBaseKey
+	public typealias AnyKey = Keys
 
 	public class Keys: BaseKey {
 		public typealias Key = Defaults.Key
@@ -34,7 +35,7 @@ public enum Defaults {
 		}
 	}
 
-	public final class Key<Value: Codable>: Keys {
+	public final class Key<Value: Codable>: AnyKey {
 		public let defaultValue: Value
 
 		/// Create a defaults key.
@@ -58,7 +59,7 @@ public enum Defaults {
 	}
 
 	@available(iOS 11.0, macOS 10.13, tvOS 11.0, watchOS 4.0, iOSApplicationExtension 11.0, macOSApplicationExtension 10.13, tvOSApplicationExtension 11.0, watchOSApplicationExtension 4.0, *)
-	public final class NSSecureCodingKey<Value: NSSecureCoding>: Keys {
+	public final class NSSecureCodingKey<Value: NSSecureCoding>: AnyKey {
 		public let defaultValue: Value
 
 		/// Create a defaults key.
@@ -82,7 +83,7 @@ public enum Defaults {
 	}
 
 	@available(iOS 11.0, macOS 10.13, tvOS 11.0, watchOS 4.0, iOSApplicationExtension 11.0, macOSApplicationExtension 10.13, tvOSApplicationExtension 11.0, watchOSApplicationExtension 4.0, *)
-	public final class NSSecureCodingOptionalKey<Value: NSSecureCoding>: Keys {
+	public final class NSSecureCodingOptionalKey<Value: NSSecureCoding>: AnyKey {
 		/// Create an optional defaults key.
 		public init(_ key: String, suite: UserDefaults = .standard) {
 			super.init(name: key, suite: suite)

Sources/Defaults/Observation+Combine.swift

@@ -1,5 +1,4 @@
 #if canImport(Combine)
-
 import Foundation
 import Combine
 
@@ -133,7 +132,7 @@ extension Defaults {
 	*/
 	@available(iOS 13.0, macOS 10.15, tvOS 13.0, watchOS 6.0, iOSApplicationExtension 13.0, macOSApplicationExtension 10.15, tvOSApplicationExtension 13.0, watchOSApplicationExtension 6.0, *)
 	public static func publisher(
-		keys: Keys...,
+		keys: AnyKey...,
 		options: ObservationOptions = [.initial]
 	) -> AnyPublisher<Void, Never> {
 		let initial = Empty<Void, Never>(completeImmediately: false).eraseToAnyPublisher()
@@ -150,5 +149,4 @@ extension Defaults {
 		return combinedPublisher
 	}
 }
-
 #endif

Sources/Defaults/Observation.swift

@@ -141,38 +141,38 @@ extension Defaults {
 		}
 	}
 
-	private static var preventPropagationThreadDictKey: String {
+	private static var preventPropagationThreadDictionaryKey: String {
 		"\(type(of: Observation.self))_threadUpdatingValuesFlag"
 	}
 
 	/**
-	Execute block without triggering events of changes made at defaults keys.
+	Execute the closure without triggering change events.
+
+	Any `Defaults` key changes made within the closure will not propagate to `Defaults` event listeners (`Defaults.observe()` and `Defaults.publisher()`). This can be useful to prevent infinite recursion when you want to change a key in the callback listening to changes for the same key.
+
+	- Note: This only works with `Defaults.observe()` and `Defaults.publisher()`. User-made KVO will not be affected.
 
-	Example:
 	```
 	let observer = Defaults.observe(keys: .key1, .key2) {
 		// …
+
 		Defaults.withoutPropagation {
-			// update some value at .key1
+			// Update `.key1` without propagating the change to listeners.
-			// this will not be propagated
 			Defaults[.key1] = 11
 		}
-		// this will be propagated
+
+		// This will be propagated.
 		Defaults[.someKey] = true
 	}
 	```
-	
-	This only works with defaults `observe` or `publisher`. User made KVO will not be affected.
 	*/
-	public static func withoutPropagation(block: () -> Void) {
+	public static func withoutPropagation(_ closure: () -> Void) {
 		// How does it work?
-		// KVO observation callbacks are executed right after change is made,
+		// KVO observation callbacks are executed right after a change is made, and run on the same thread as the caller. So it works by storing a flag in the current thread's dictionary, which is then evaluated in the callback.
-		// and run on the same thread as the caller. So it works by storing a flag in current
-		// thread's dictionary, which is then evaluated in `observeValue` callback
 
-		let key = preventPropagationThreadDictKey
+		let key = preventPropagationThreadDictionaryKey
 		Thread.current.threadDictionary[key] = true
-		block()
+		closure()
 		Thread.current.threadDictionary[key] = false
 	}
 
@@ -236,7 +236,7 @@ extension Defaults {
 				return
 			}
 
-			let key = preventPropagationThreadDictKey
+			let key = preventPropagationThreadDictionaryKey
 			let updatingValuesFlag = (Thread.current.threadDictionary[key] as? Bool) ?? false
 			guard !updatingValuesFlag else {
 				return
@@ -260,7 +260,7 @@ extension Defaults {
 		}
 
 		private var observables: [SuiteKeyPair]
-		private var lifetimeAssociation: LifetimeAssociation? = nil
+		private var lifetimeAssociation: LifetimeAssociation?
 		private let callback: UserDefaultsKeyObservation.Callback
 
 		init(observables: [(suite: UserDefaults, key: String)], callback: @escaping UserDefaultsKeyObservation.Callback) {
@@ -279,14 +279,14 @@ extension Defaults {
 					self,
 					forKeyPath: observable.key,
 					options: options.toNSKeyValueObservingOptions,
-					context: &type(of: self).observationContext
+					context: &Self.observationContext
 				)
 			}
 		}
 
 		public func invalidate() {
 			for observable in observables {
-				observable.suite?.removeObserver(self, forKeyPath: observable.key, context: &type(of: self).observationContext)
+				observable.suite?.removeObserver(self, forKeyPath: observable.key, context: &Self.observationContext)
 				observable.suite = nil
 			}
 
@@ -313,7 +313,7 @@ extension Defaults {
 			context: UnsafeMutableRawPointer?
 		) {
 			guard
-				context == &type(of: self).observationContext
+				context == &Self.observationContext
 			else {
 				super.observeValue(forKeyPath: keyPath, of: object, change: change, context: context)
 				return
@@ -326,7 +326,7 @@ extension Defaults {
 				return
 			}
 
-			let key = preventPropagationThreadDictKey
+			let key = preventPropagationThreadDictionaryKey
 			let updatingValuesFlag = (Thread.current.threadDictionary[key] as? Bool) ?? false
 			if updatingValuesFlag {
 				return
@@ -401,7 +401,7 @@ extension Defaults {
 	}
 
 	/**
-	Observe multiple keys of any type, but without specific information about changes.
+	Observe multiple keys of any type, but without any information about the changes.
 
 	```
 	extension Defaults.Keys {
@@ -410,12 +410,12 @@ extension Defaults {
 	}
 
 	let observer = Defaults.observe(keys: .setting1, .setting2) {
-		//...
+		// …
 	}
 	```
 	*/
 	public static func observe(
-		keys: Keys...,
+		keys: AnyKey...,
 		options: ObservationOptions = [.initial],
 		handler: @escaping () -> Void
 	) -> Observation {

Sources/Defaults/SwiftUI.swift

@@ -1,5 +1,4 @@
 #if canImport(Combine)
-
 import SwiftUI
 import Combine
 
@@ -111,5 +110,4 @@ public struct Default<Value: Codable>: DynamicProperty {
 		key.reset()
 	}
 }
-
 #endif

Tests/DefaultsTests/DefaultsTests.swift

@@ -369,7 +369,7 @@ final class DefaultsTests: XCTestCase {
 
 		let publisher = Defaults
 			.publisher(key)
-			.compactMap { $0.newValue }
+			.map(\.newValue)
 			.eraseToAnyPublisher()
 			.collect(2)
 
@@ -579,10 +579,7 @@ final class DefaultsTests: XCTestCase {
 		waitForExpectations(timeout: 10)
 	}
 
-	/**
+	// This checks if the callback is still being called if the value is changed on a second thread while the initial thread is doing some long running task.
-	This checks if callback is still being called, if value is changed on second thread,
-	while initial thread is doing some long lasting task.
-	*/
 	func testObservePreventPropagationMultipleThreads() {
 		let key1 = Defaults.Key<Int?>("preventPropagation3", default: nil)
 		let expect = expectation(description: "No infinite recursion")
@@ -610,9 +607,7 @@ final class DefaultsTests: XCTestCase {
 		waitForExpectations(timeout: 10)
 	}
 
-	/**
+	// Check if propagation prevention works across multiple observations.
-	Check if propagation prevention works across multiple observations
-	*/
 	func testObservePreventPropagationMultipleObservations() {
 		let key1 = Defaults.Key<Bool?>("preventPropagation4", default: nil)
 		let key2 = Defaults.Key<Bool?>("preventPropagation5", default: nil)

readme.md

@@ -239,23 +239,6 @@ Defaults[.isUnicornMode] = true
 
 The observation will be valid until `self` is deinitialized.
 
-### Control propagation of change events
-
-```swift
-let observer = Defaults.observe(keys: .key1, .key2) {
-	// …
-	Defaults.withoutPropagation {
-		// update some value at .key1
-		// this will not be propagated
-		Defaults[.key1] = 11
-	}
-	// this will be propagated
-	Defaults[.someKey] = true
-}
-```
-
-Changes made within `Defaults.withoutPropagation` block, will not be propagated to observation callbacks, and therefore will prevent infinite recursion.
-
 ### Reset keys to their default values
 
 ```swift
@@ -274,6 +257,24 @@ Defaults[.isUnicornMode]
 
 This works for a `Key` with an optional too, which will be reset back to `nil`.
 
+### Control propagation of change events
+
+Changes made within the `Defaults.withoutPropagation` closure will not be propagated to observation callbacks (`Defaults.observe()` or `Defaults.publisher()`), and therefore could prevent infinite recursion.
+
+```swift
+let observer = Defaults.observe(keys: .key1, .key2) {
+		// …
+
+		Defaults.withoutPropagation {
+			// Update `.key1` without propagating the change to listeners.
+			Defaults[.key1] = 11
+		}
+
+		// This will be propagated.
+		Defaults[.someKey] = true
+	}
+```
+
 ### It's just `UserDefaults` with sugar
 
 This works too:
@@ -408,9 +409,9 @@ By default, it will also trigger an initial event on creation. This can be usefu
 
 Type: `func`
 
-Observe changes to multiple keys of any type, but without specific information about changes.
+Observe multiple keys of any type, but without any information about the changes.
 
-Options same as in  `observe` for a single key. 
+Options are the same as in `.observe(…)` for a single key.
 
 #### `Defaults.publisher(_ key:, options:)`
 
@@ -500,11 +501,11 @@ Break the lifetime tie created by `tieToLifetime(of:)`, if one exists.
 
 The effects of any call to `tieToLifetime(of:)` are reversed. Note however that if the tied-to object has already died, then the observation is already invalid and this method has no logical effect.
 
-#### `Defaults.withoutPropagation(_ block:)`
+#### `Defaults.withoutPropagation(_ closure:)`
 
-Execute block without emitting events of changes made at defaults keys. 
+Execute the closure without triggering change events.
 
-Changes made within the block will not be propagated to observation callbacks. This only works with defaults `observe` or `publisher`. User made KVO will not be affected.
+Any `Defaults` key changes made within the closure will not propagate to `Defaults` event listeners (`Defaults.observe()` and `Defaults.publisher()`). This can be useful to prevent infinite recursion when you want to change a key in the callback listening to changes for the same key.
 
 ### `@Default(_ key:)`