Introduce @CaseIterable (#2)

Author: davdroman

Package.swift

@@ -4,7 +4,7 @@ import CompilerPluginSupport
 import PackageDescription
 
 let package = Package(
-	name: "StaticMemberIterable",
+	name: "swift-iterable-macros",
 	platforms: [
 		.iOS(.v13),
 		.macOS(.v10_15),
@@ -13,17 +13,49 @@ let package = Package(
 		.watchOS(.v6),
 	],
 	products: [
+		.library(name: "IterableMacros", targets: ["IterableMacros"]),
 		.library(name: "StaticMemberIterable", targets: ["StaticMemberIterable"]),
+		.library(name: "CaseIterable", targets: ["CaseIterable"]),
 	],
 	targets: [
-		.target(name: "StaticMemberIterable", dependencies: ["StaticMemberIterableMacro"]),
+		.target(
+			name: "IterableMacros",
+			dependencies: [
+				"StaticMemberIterable",
+				"CaseIterable",
+			],
+		),
+
+		.target(
+			name: "StaticMemberIterable",
+			dependencies: [
+				"IterableSupport",
+				"StaticMemberIterableMacro",
+			],
+		),
+
+		.target(
+			name: "CaseIterable",
+			dependencies: [
+				"IterableSupport",
+				"CaseIterableMacro",
+			],
+		),
 
 		.macro(
 			name: "StaticMemberIterableMacro",
 			dependencies: [
 				.product(name: "SwiftCompilerPlugin", package: "swift-syntax"),
 				.product(name: "SwiftSyntaxMacros", package: "swift-syntax"),
-			]
+			],
+		),
+
+		.macro(
+			name: "CaseIterableMacro",
+			dependencies: [
+				.product(name: "SwiftCompilerPlugin", package: "swift-syntax"),
+				.product(name: "SwiftSyntaxMacros", package: "swift-syntax"),
+			],
 		),
 
 		.testTarget(
@@ -35,9 +67,23 @@ let package = Package(
 				// For some reason, with Swift Syntax prebuilts enabled, we need to depend on SwiftCompilerPlugin here to work around error:
 				// Compilation search paths unable to resolve module dependency: 'SwiftCompilerPlugin'
 				.product(name: "SwiftCompilerPlugin", package: "swift-syntax"),
-			]
+			],
 		),
-	]
+
+		.testTarget(
+			name: "CaseIterableTests",
+			dependencies: [
+				"CaseIterable",
+				"CaseIterableMacro",
+				.product(name: "MacroTesting", package: "swift-macro-testing"),
+				// For some reason, with Swift Syntax prebuilts enabled, we need to depend on SwiftCompilerPlugin here to work around error:
+				// Compilation search paths unable to resolve module dependency: 'SwiftCompilerPlugin'
+				.product(name: "SwiftCompilerPlugin", package: "swift-syntax"),
+			],
+		),
+
+		.target(name: "IterableSupport"),
+	],
 )
 
 package.dependencies += [

README.md

@@ -1,6 +1,9 @@
-# StaticMemberIterable
+# swift-iterable-macros
 
-StaticMemberIterable is a Swift macro that synthesizes collections describing every `static let` defined in a struct, enum, or class.
+swift-iterable-macros hosts Swift macros that generate iterable collections for your types:
+
+- `@StaticMemberIterable` synthesizes collections describing every `static let` defined in a struct, enum, or class.
+- `@CaseIterable` mirrors Swift’s `CaseIterable` but keeps a case’s name, value, and presentation metadata.
 
 This is handy for building fixtures, demo data, menus, or anywhere you want a single source of truth for a handful of well-known static members.
 
@@ -9,14 +12,21 @@ This is handy for building fixtures, demo data, menus, or anywhere you want a si
 Add the dependency and product to your `Package.swift`:
 
 ```swift
-.package(url: "https://github.com/davdroman/StaticMemberIterable", from: "0.1.0"),
+.package(url: "https://github.com/davdroman/swift-iterable-macros", from: "0.2.0"),
+```
+
+```swift
+.product(name: "IterableMacros", package: "swift-iterable-macros"),
 ```
 
+`IterableMacros` re-exports both modules. If you only need one macro, depend on it explicitly instead:
+
 ```swift
-.product(name: "StaticMemberIterable", package: "StaticMemberIterable"),
+.product(name: "StaticMemberIterable", package: "swift-iterable-macros"),
+.product(name: "CaseIterable", package: "swift-iterable-macros"),
 ```
 
-## Usage
+## Static members (`@StaticMemberIterable`)
 
 ```swift
 import StaticMemberIterable
@@ -29,7 +39,7 @@ enum ColorPalette {
     static let stardust: Color = Color(red: 0.68, green: 0.51, blue: 0.78)
 }
 
-ColorPalette.allStaticMembers.map(\.value)   // [.orange, .indigo, .purple] as [Color]
+ColorPalette.allStaticMembers.map(\.value)   // [Color(red: 1.00, ...), ...]
 ColorPalette.allStaticMembers.map(\.title)   // ["Sunrise", "Moonlight", "Stardust"]
 ColorPalette.allStaticMembers.map(\.keyPath) // [\ColorPalette.sunrise, ...] as [KeyPath<ColorPalette.Type, Color>]
 ```
@@ -40,6 +50,7 @@ Each synthesized entry is a `StaticMember<Container, Value>`: an `Identifiable`
 
 ```swift
 ForEach(ColorPalette.allStaticMembers) { $color in
+    let color = $color.value
     RoundedRectangle(cornerRadius: 12)
         .fill(color)
         .overlay(Text($color.title))
@@ -56,13 +67,36 @@ ForEach(ColorPalette.allStaticMembers) { $color in
 
 Because it is a property wrapper, you can also project (`$member`) when you use it on your own properties, and `Identifiable` conformance makes it slot neatly into `ForEach`.
 
+## Enum cases (`@CaseIterable`)
+
+```swift
+import CaseIterable
+
+@CaseIterable
+enum MenuSection {
+    case breakfast
+    case lunch
+    case dinner
+}
+
+ForEach(MenuSection.allCases) { $section in
+    Text($section.title)
+        .tag($section.id)
+}
+```
+
+`@CaseIterable` produces an explicit `allCases: [CaseOf<Enum>]`. `CaseOf` is also a property wrapper, exposing the case name, a title-cased variant, the enum value, and a stable `id` derived from the name.
+
 ### Access control
 
 Need public-facing lists? Pass the desired access modifier:
 
 ```swift
 @StaticMemberIterable(.public)
 struct Coffee { ... }
+
+@CaseIterable(.public)
+enum MenuSection { ... }
 ```
 
 Supported modifiers:

Sources/CaseIterable/CaseIterable.swift

@@ -0,0 +1,18 @@
+@attached(
+	member,
+	names: named(allCases), named(subscript(dynamicMember:))
+)
+public macro CaseIterable(
+	_ access: CaseIterableAccess? = nil,
+) = #externalMacro(
+	module: "CaseIterableMacro",
+	type: "CaseIterableMacro",
+)
+
+public enum CaseIterableAccess {
+	case `public`
+	case `internal`
+	case `package`
+	case `fileprivate`
+	case `private`
+}

Sources/CaseIterable/CaseOf.swift

@@ -0,0 +1,28 @@
+import IterableSupport
+
+@propertyWrapper
+public struct CaseOf<Enum> {
+	public let name: String
+
+	private let storage: Enum
+
+	public var wrappedValue: Enum { storage }
+	public var projectedValue: CaseOf<Enum> { self }
+	public var value: Enum { storage }
+	public var title: String { name.memberIdentifierTitle() }
+
+	public init(name: String, value: Enum) {
+		self.name = name
+		self.storage = value
+	}
+
+	public init(projectedValue: CaseOf<Enum>) {
+		self.init(name: projectedValue.name, value: projectedValue.value)
+	}
+}
+
+extension CaseOf: Identifiable {
+	public var id: String { name }
+}
+
+extension CaseOf: @unchecked Sendable where Enum: Sendable {}