Case key path support

.github/workflows/ci.yml

@@ -20,7 +20,7 @@ jobs:
           - test
           # - benchmarks
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Select Xcode ${{ matrix.xcode }}
         run: sudo xcode-select -s /Applications/Xcode_${{ matrix.xcode }}.app
       - name: System
@@ -29,15 +29,15 @@ jobs:
         run: make ${{ matrix.command }}
 
   ubuntu_tests:
+    name: Ubuntu (Swift ${{ matrix.swift }})
+    runs-on: ubuntu-20.04
     strategy:
       matrix:
-        os: [ubuntu-20.04]
-
-    runs-on: ${{ matrix.os }}
-
+        swift:
+          - '5.9'
     steps:
-      - uses: actions/checkout@v3
-      - name: Build
-        run: swift build
-      - name: Run tests
-        run: swift test
+      - uses: swift-actions/setup-swift@v1
+        with:
+          swift-version: ${{ matrix.swift }}
+      - uses: actions/checkout@v4
+      - run: swift test

Package.resolved

@@ -23,8 +23,8 @@
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/pointfreeco/swift-case-paths",
       "state" : {
-        "revision" : "5da6989aae464f324eef5c5b52bdb7974725ab81",
-        "version" : "1.0.0"
+        "branch" : "case-key-paths",
+        "revision" : "7112451690777c2145aa86310d7f205c40e40998"
       }
     },
     {
@@ -36,6 +36,15 @@
         "version" : "1.0.0"
       }
     },
+    {
+      "identity" : "swift-syntax",
+      "kind" : "remoteSourceControl",
+      "location" : "https://github.com/apple/swift-syntax.git",
+      "state" : {
+        "revision" : "6ad4ea24b01559dde0773e3d091f1b9e36175036",
+        "version" : "509.0.2"
+      }
+    },
     {
       "identity" : "xctest-dynamic-overlay",
       "kind" : "remoteSourceControl",

Package.swift

@@ -18,8 +18,8 @@ let package = Package(
   ],
   dependencies: [
     .package(url: "https://github.com/apple/swift-docc-plugin", from: "1.0.0"),
-    .package(url: "https://github.com/pointfreeco/swift-case-paths", from: "1.0.0"),
     .package(url: "https://github.com/google/swift-benchmark", from: "0.1.1"),
+    .package(url: "https://github.com/pointfreeco/swift-case-paths", branch: "case-key-paths"),
   ],
   targets: [
     .target(

Sources/Parsing/Conversions/Enum.swift

@@ -7,17 +7,23 @@ extension Conversion {
   /// Useful for transforming the output of a ``ParserPrinter`` into an enum:
   ///
   /// ```swift
+  /// @CasePathable
   /// enum Expression {
   ///   case add(Int, Int)
   ///   ...
   /// }
   ///
-  /// let add = ParsePrint(.case(Expression.add)) {
-  ///   Int.parser()
-  ///   "+"
-  ///   Int.parser()
+  /// struct Add: ParserPrinter{
+  ///   var body: some ParserPrinter<Substring, Expression> {
+  ///     ParsePrint(.case(\Expression.Cases.add)) {
+  ///       Int.parser()
+  ///       "+"
+  ///       Int.parser()
+  ///     }
+  ///   }
   /// }
-  /// try add.parse("1+2")  // Expression.add(1, 2)
+  ///
+  /// try Add().parse("1+2")  // Expression.add(1, 2)
   /// ```
   ///
   /// To transform the output of a ``ParserPrinter`` into a struct, see ``memberwise(_:)``.
@@ -27,22 +33,29 @@ extension Conversion {
   ///   synthesized for structs.
   /// - Returns: A conversion that can embed the associated values of an enum case into the case,
   ///   and extract the associated values from the case.
+  @inlinable
+  public static func `case`<Values, Enum: CasePathable>(
+    _ keyPath: CaseKeyPath<Enum, Values>
+  ) -> Self where Self == AnyCasePath<Enum, Values> {
+    AnyCasePath(keyPath)
+  }
+
   @inlinable
   public static func `case`<Values, Enum>(
     _ initializer: @escaping (Values) -> Enum
-  ) -> Self where Self == CasePath<Enum, Values> {
+  ) -> Self where Self == AnyCasePath<Enum, Values> {
     /initializer
   }
 
   @inlinable
   public static func `case`<Enum>(
     _ initializer: Enum
-  ) -> Self where Self == CasePath<Enum, Void> {
+  ) -> Self where Self == AnyCasePath<Enum, Void> {
     /initializer
   }
 }
 
-extension CasePath: Conversion {
+extension AnyCasePath: Conversion {
   @inlinable
   public func apply(_ input: Value) -> Root {
     self.embed(input)