Remove @dynamicMember generally

.gitignore

@@ -3,3 +3,4 @@
 /*.xcodeproj
 /build
 /docs
+/.swiftpm

README.md

@@ -32,7 +32,7 @@ let foo = try Path.root.join("foo").copy(into: Path.root.join("bar").mkdir())
 print(foo)         // => /bar/foo
 print(foo.isFile)  // => true
 
-// we support dynamic members (_use_sparingly_):
+// we support dynamic-member-syntax when joining named static members, eg:
 let prefs = Path.home.Library.Preferences  // => /Users/mxcl/Library/Preferences
 
 // a practical example: installing a helper executable
@@ -107,10 +107,11 @@ We support `@dynamicMemberLookup`:
 let ls = Path.root.usr.bin.ls  // => /usr/bin/ls
 ```
 
-This is less commonly useful than you would think, hence our documentation
-does not use it. Usually you are joining variables or other `String` arguments
-or trying to describe files (and files usually have extensions). However when
-you need it, it’s *lovely*.
+We only provide this for “starting” function, eg. `Path.home` or `Bundle.path`.
+This is because we found in practice it was easy to write incorrect code, since
+everything would compile if we allowed arbituary variables to take *any* named
+property as valid syntax. What we have is what you want most of the time but
+much less dangerous.
 
 ## Initializing from user-input
 

Sources/Extensions.swift

@@ -13,46 +13,46 @@ public extension Bundle {
      Returns the path for the shared-frameworks directory in this bundle.
      - Note: This is typically `ShareFrameworks`
     */
-    var sharedFrameworks: Path {
-        return sharedFrameworksPath.flatMap(Path.init) ?? defaultSharedFrameworksPath
+    var sharedFrameworks: DynamicPath {
+        return sharedFrameworksPath.flatMap(DynamicPath.init) ?? defaultSharedFrameworksPath
     }
 
     /**
      Returns the path for the private-frameworks directory in this bundle.
      - Note: This is typically `Frameworks`
     */
-    var privateFrameworks: Path {
-        return privateFrameworksPath.flatMap(Path.init) ?? defaultSharedFrameworksPath
+    var privateFrameworks: DynamicPath {
+        return privateFrameworksPath.flatMap(DynamicPath.init) ?? defaultSharedFrameworksPath
     }
 
     /// Returns the path for the resources directory in this bundle.
-    var resources: Path {
-        return resourcePath.flatMap(Path.init) ?? defaultResourcesPath
+    var resources: DynamicPath {
+        return resourcePath.flatMap(DynamicPath.init) ?? defaultResourcesPath
     }
 
     /// Returns the path for this bundle.
-    var path: Path {
-        return Path(string: bundlePath)
+    var path: DynamicPath {
+        return DynamicPath(string: bundlePath)
     }
 
     /// Returns the executable for this bundle, if there is one, not all bundles have one hence `Optional`.
-    var executable: Path? {
-        return executablePath.flatMap(Path.init)
+    var executable: DynamicPath? {
+        return executablePath.flatMap(DynamicPath.init)
     }
 }
 
 /// Extensions on `String` that work with `Path` rather than `String` or `URL`
 public extension String {
     /// Initializes this `String` with the contents of the provided path.
     @inlinable
-    init(contentsOf path: Path) throws {
+    init<P: Pathish>(contentsOf path: P) throws {
         try self.init(contentsOfFile: path.string)
     }
 
     /// - Returns: `to` to allow chaining
     @inlinable
     @discardableResult
-    func write(to: Path, atomically: Bool = false, encoding: String.Encoding = .utf8) throws -> Path {
+    func write<P: Pathish>(to: P, atomically: Bool = false, encoding: String.Encoding = .utf8) throws -> P {
         try write(toFile: to.string, atomically: atomically, encoding: encoding)
         return to
     }
@@ -62,14 +62,14 @@ public extension String {
 public extension Data {
     /// Initializes this `Data` with the contents of the provided path.
     @inlinable
-    init(contentsOf path: Path) throws {
+    init<P: Pathish>(contentsOf path: P) throws {
         try self.init(contentsOf: path.url)
     }
 
     /// - Returns: `to` to allow chaining
     @inlinable
     @discardableResult
-    func write(to: Path, atomically: Bool = false) throws -> Path {
+    func write<P: Pathish>(to: P, atomically: Bool = false) throws -> P {
         let opts: NSData.WritingOptions
         if atomically {
         #if !os(Linux)
@@ -89,39 +89,39 @@ public extension Data {
 public extension FileHandle {
     /// Initializes this `FileHandle` for reading at the location of the provided path.
     @inlinable
-    convenience init(forReadingAt path: Path) throws {
+    convenience init<P: Pathish>(forReadingAt path: P) throws {
         try self.init(forReadingFrom: path.url)
     }
 
     /// Initializes this `FileHandle` for writing at the location of the provided path.
     @inlinable
-    convenience init(forWritingAt path: Path) throws {
+    convenience init<P: Pathish>(forWritingAt path: P) throws {
         try self.init(forWritingTo: path.url)
     }
 
     /// Initializes this `FileHandle` for reading and writing at the location of the provided path.
     @inlinable
-    convenience init(forUpdatingAt path: Path) throws {
+    convenience init<P: Pathish>(forUpdatingAt path: P) throws {
         try self.init(forUpdating: path.url)
     }
 }
 
 internal extension Bundle {
-    var defaultSharedFrameworksPath: Path {
+    var defaultSharedFrameworksPath: DynamicPath {
       #if os(macOS)
-        return path.join("Contents/Frameworks")
+        return path.Contents.Frameworks
       #elseif os(Linux)
-        return path.join("lib")
+        return path.lib
       #else
-        return path.join("Frameworks")
+        return path.Frameworks
       #endif
     }
 
-    var defaultResourcesPath: Path {
+    var defaultResourcesPath: DynamicPath {
       #if os(macOS)
-        return path.join("Contents/Resources")
+        return path.Contents.Resources
       #elseif os(Linux)
-        return path.join("share")
+        return path.share
       #else
         return path
       #endif

Sources/Path+Attributes.swift

@@ -1,6 +1,6 @@
 import Foundation
 
-public extension Path {
+public extension Pathish {
     //MARK: Filesystem Attributes
 
     /**
@@ -38,7 +38,7 @@ public extension Path {
     @discardableResult
     func chmod(_ octal: Int) throws -> Path {
         try FileManager.default.setAttributes([.posixPermissions: octal], ofItemAtPath: string)
-        return self
+        return Path(self)
     }
 
     /**
@@ -57,7 +57,7 @@ public extension Path {
             try FileManager.default.setAttributes(attrs, ofItemAtPath: string)
         }
     #endif
-        return self
+        return Path(self)
     }
 
     /**
@@ -73,22 +73,18 @@ public extension Path {
         do {
             attrs = try FileManager.default.attributesOfItem(atPath: string)
         } catch CocoaError.fileReadNoSuchFile {
-            return self
+            return Path(self)
         }
         let b = attrs[.immutable] as? Bool ?? false
         if b {
             attrs[.immutable] = false
             try FileManager.default.setAttributes(attrs, ofItemAtPath: string)
         }
     #endif
-        return self
-    }
-
-    enum Kind {
-        case file, symlink, directory
+        return Path(self)
     }
 
-    var kind: Kind? {
+    var kind: Path.Kind? {
         var buf = stat()
         guard lstat(string, &buf) == 0 else {
             return nil
@@ -102,3 +98,9 @@ public extension Path {
         }
     }
 }
+
+public extension Path {
+    enum Kind {
+        case file, symlink, directory
+    }
+}

Sources/Path+Codable.swift

@@ -23,18 +23,19 @@ public extension CodingUserInfoKey {
  Provided for relative-path coding. See the instructions in our
  [README](https://github.com/mxcl/Path.swift/#codable).
 */
-extension Path: Codable {    
+extension Path: Codable {
     /// - SeeAlso: `CodingUserInfoKey.relativePath`
     /// :nodoc:
     public init(from decoder: Decoder) throws {
         let value = try decoder.singleValueContainer().decode(String.self)
         if value.hasPrefix("/") {
             string = value
-        } else {
-            guard let root = decoder.userInfo[.relativePath] as? Path else {
-                throw DecodingError.dataCorrupted(.init(codingPath: [], debugDescription: "Path cannot decode a relative path if `userInfo[.relativePath]` not set to a Path object."))
-            }
+        } else if let root = decoder.userInfo[.relativePath] as? Path {
+            string = (root/value).string
+        } else if let root = decoder.userInfo[.relativePath] as? DynamicPath {
             string = (root/value).string
+        } else {
+            throw DecodingError.dataCorrupted(.init(codingPath: [], debugDescription: "Path cannot decode a relative path if `userInfo[.relativePath]` not set to a Path object."))
         }
     }
 
@@ -44,6 +45,8 @@ extension Path: Codable {
         var container = encoder.singleValueContainer()
         if let root = encoder.userInfo[.relativePath] as? Path {
             try container.encode(relative(to: root))
+        } else if let root = encoder.userInfo[.relativePath] as? DynamicPath {
+            try container.encode(relative(to: root))
         } else {
             try container.encode(string)
         }

Sources/Path+CommonDirectories.swift

@@ -4,17 +4,17 @@ extension Path {
     //MARK: Common Directories
 
     /// Returns a `Path` containing `FileManager.default.currentDirectoryPath`.
-    public static var cwd: Path {
-        return Path(string: FileManager.default.currentDirectoryPath)
+    public static var cwd: DynamicPath {
+        return .init(string: FileManager.default.currentDirectoryPath)
     }
 
     /// Returns a `Path` representing the root path.
-    public static var root: Path {
-        return Path(string: "/")
+    public static var root: DynamicPath {
+        return .init(string: "/")
     }
 
     /// Returns a `Path` representing the user’s home directory
-    public static var home: Path {
+    public static var home: DynamicPath {
         let string: String
       #if os(macOS)
         if #available(OSX 10.12, *) {
@@ -25,30 +25,30 @@ extension Path {
       #else
         string = NSHomeDirectory()
       #endif
-        return Path(string: string)
+        return .init(string: string)
     }
 
     /// Helper to allow search path and domain mask to be passed in.
-    private static func path(for searchPath: FileManager.SearchPathDirectory) -> Path {
+    private static func path(for searchPath: FileManager.SearchPathDirectory) -> DynamicPath {
     #if os(Linux)
         // the urls(for:in:) function is not implemented on Linux
         //TODO strictly we should first try to use the provided binary tool
 
-        let foo = { ProcessInfo.processInfo.environment[$0].flatMap(Path.init) ?? $1 }
+        let foo = { ProcessInfo.processInfo.environment[$0].flatMap(Path.init).map(DynamicPath.init) ?? $1 }
 
         switch searchPath {
         case .documentDirectory:
-            return Path.home/"Documents"
+            return Path.home.Documents
         case .applicationSupportDirectory:
-            return foo("XDG_DATA_HOME", Path.home/".local/share")
+            return foo("XDG_DATA_HOME", Path.home[dynamicMember: ".local/share"])
         case .cachesDirectory:
-            return foo("XDG_CACHE_HOME", Path.home/".cache")
+            return foo("XDG_CACHE_HOME", Path.home[dynamicMember: ".cache"])
         default:
             fatalError()
         }
     #else    
         guard let pathString = FileManager.default.urls(for: searchPath, in: .userDomainMask).first?.path else { return defaultUrl(for: searchPath) }
-        return Path(string: pathString)
+        return DynamicPath(string: pathString)
     #endif
     }
 
@@ -57,7 +57,7 @@ extension Path {
      - Note: There is no standard location for documents on Linux, thus we return `~/Documents`.
      - Note: You should create a subdirectory before creating any files.
      */
-    public static var documents: Path {
+    public static var documents: DynamicPath {
         return path(for: .documentDirectory)
     }
 
@@ -66,7 +66,7 @@ extension Path {
      - Note: On Linux this is `XDG_CACHE_HOME`.
      - Note: You should create a subdirectory before creating any files.
      */
-    public static var caches: Path {
+    public static var caches: DynamicPath {
         return path(for: .cachesDirectory)
     }
 
@@ -75,20 +75,20 @@ extension Path {
      - Note: On Linux is `XDG_DATA_HOME`.
      - Note: You should create a subdirectory before creating any files.
      */
-    public static var applicationSupport: Path {
+    public static var applicationSupport: DynamicPath {
         return path(for: .applicationSupportDirectory)
     }
 }
 
 #if !os(Linux)
-func defaultUrl(for searchPath: FileManager.SearchPathDirectory) -> Path {
+func defaultUrl(for searchPath: FileManager.SearchPathDirectory) -> DynamicPath {
     switch searchPath {
     case .documentDirectory:
-        return Path.home/"Documents"
+        return Path.home.Documents
     case .applicationSupportDirectory:
-        return Path.home/"Library/Application Support"
+        return Path.home.Library[dynamicMember: "Application Support"]
     case .cachesDirectory:
-        return Path.home/"Library/Caches"
+        return Path.home.Library.Caches
     default:
         fatalError()
     }