make subscript generic

Author: koenpunt

Configurations/Configurations.swift

@@ -14,14 +14,9 @@ public class Configuration: NSObject {
 
     public private(set) var configurationName: String?
     private var dictionary: NSDictionary!
-    
-    public static func defaultConfiguration() -> Configuration {
-        struct Static {
-            static var instance = Configuration()
-        }
-        return Static.instance
-    }
-    
+
+    public static let `default` = Configuration()
+
     private override init() {
         super.init()
 
@@ -30,7 +25,8 @@ public class Configuration: NSObject {
         self.configurationName = bundle.infoDictionary![CurrentConfigurationPlistKey] as? String
 
         guard self.configurationName != nil else {
-            fatalError("No Configuration property found in plist")
+            assertionFailure("No Configuration property found in plist")
+            return
         }
 
         let plistName = bundle.infoDictionary![self.ConfigurationPlistKey] as! String
@@ -40,9 +36,9 @@ public class Configuration: NSObject {
         self.dictionary = dictionary?.value(forKey: self.configurationName!) as! NSDictionary
     }
 
-    public subscript(key: String) -> AnyObject? {
+    public subscript<T>(key: String) -> T? {
         get {
-            return self.dictionary.value(forKey: key) as AnyObject
+            return self.dictionary.value(forKey: key) as? T
         }
     }
 

ConfigurationsExample/ConfigurationsExampleIOS/ViewController.swift

@@ -16,11 +16,9 @@ class ViewController: UIViewController {
     override func viewDidLoad() {
         super.viewDidLoad()
 
-        let configuration = Configuration.defaultConfiguration()
+        let configuration = Configuration.default
 
-        if let value = configuration["Greeting"] as? String {
-            self.greetingLabel.text = value
-        }
+        self.greetingLabel.text = configuration["Greeting"]!
     }
 
     override func didReceiveMemoryWarning() {

ConfigurationsExample/ConfigurationsExampleOSX/AppDelegate.swift

@@ -15,15 +15,11 @@ class AppDelegate: NSObject, NSApplicationDelegate {
     @IBOutlet weak var window: NSWindow!
     @IBOutlet weak var greetingLabel: NSTextField!
 
-
     func applicationDidFinishLaunching(_ aNotification: Notification) {
 
-        let configuration = Configuration.defaultConfiguration()
-        
-        if let value = configuration["Greeting"] as? String {
-            self.greetingLabel.stringValue = value
-        }
+        let configuration = Configuration.default
 
+        self.greetingLabel.stringValue = configuration["Greeting"]!
     }
 
     func applicationWillTerminate(_ aNotification: Notification) {