--- a/dstep/foundation/NSUndoManager.d	Mon Aug 03 15:31:48 2009 +0200
+++ b/dstep/foundation/NSUndoManager.d	Sun Jan 03 22:06:11 2010 +0100
@@ -7,41 +7,102 @@
 module dstep.foundation.NSUndoManager;
 
 import dstep.foundation.NSArray;
+import dstep.foundation.NSObjCRuntime;
 import dstep.foundation.NSObject;
 import dstep.foundation.NSString;
 import dstep.objc.bridge.Bridge;
-import dstep.objc.objc : id;
+import dstep.objc.objc;
+
+
 
 import bindings = dstep.foundation.NSUndoManager_bindings;
 
-const NSString NSUndoManagerCheckpointNotification;
-const NSString NSUndoManagerWillUndoChangeNotification;
-const NSString NSUndoManagerWillRedoChangeNotification;
-const NSString NSUndoManagerDidUndoChangeNotification;
-const NSString NSUndoManagerDidRedoChangeNotification;
-const NSString NSUndoManagerDidOpenUndoGroupNotification;
-const NSString NSUndoManagerWillCloseUndoGroupNotification;
+private
+{
+	NSString NSUndoManagerCheckpointNotification_;
+	NSString NSUndoManagerWillUndoChangeNotification_;
+	NSString NSUndoManagerWillRedoChangeNotification_;
+	NSString NSUndoManagerDidUndoChangeNotification_;
+	NSString NSUndoManagerDidRedoChangeNotification_;
+	NSString NSUndoManagerDidOpenUndoGroupNotification_;
+	NSString NSUndoManagerWillCloseUndoGroupNotification_;
+}
+
+NSString NSUndoManagerCheckpointNotification ()
+{
+	if (NSUndoManagerCheckpointNotification_)
+		return NSUndoManagerCheckpointNotification_;
+		
+	return NSUndoManagerCheckpointNotification_ = new NSString(bindings.NSUndoManagerCheckpointNotification);
+}
+
+NSString NSUndoManagerWillUndoChangeNotification ()
+{
+	if (NSUndoManagerWillUndoChangeNotification_)
+		return NSUndoManagerWillUndoChangeNotification_;
+		
+	return NSUndoManagerWillUndoChangeNotification_ = new NSString(bindings.NSUndoManagerWillUndoChangeNotification);
+}
+
+NSString NSUndoManagerWillRedoChangeNotification ()
+{
+	if (NSUndoManagerWillRedoChangeNotification_)
+		return NSUndoManagerWillRedoChangeNotification_;
+		
+	return NSUndoManagerWillRedoChangeNotification_ = new NSString(bindings.NSUndoManagerWillRedoChangeNotification);
+}
+
+NSString NSUndoManagerDidUndoChangeNotification ()
+{
+	if (NSUndoManagerDidUndoChangeNotification_)
+		return NSUndoManagerDidUndoChangeNotification_;
+		
+	return NSUndoManagerDidUndoChangeNotification_ = new NSString(bindings.NSUndoManagerDidUndoChangeNotification);
+}
+
+NSString NSUndoManagerDidRedoChangeNotification ()
+{
+	if (NSUndoManagerDidRedoChangeNotification_)
+		return NSUndoManagerDidRedoChangeNotification_;
+		
+	return NSUndoManagerDidRedoChangeNotification_ = new NSString(bindings.NSUndoManagerDidRedoChangeNotification);
+}
+
+NSString NSUndoManagerDidOpenUndoGroupNotification ()
+{
+	if (NSUndoManagerDidOpenUndoGroupNotification_)
+		return NSUndoManagerDidOpenUndoGroupNotification_;
+		
+	return NSUndoManagerDidOpenUndoGroupNotification_ = new NSString(bindings.NSUndoManagerDidOpenUndoGroupNotification);
+}
+
+NSString NSUndoManagerWillCloseUndoGroupNotification ()
+{
+	if (NSUndoManagerWillCloseUndoGroupNotification_)
+		return NSUndoManagerWillCloseUndoGroupNotification_;
+		
+	return NSUndoManagerWillCloseUndoGroupNotification_ = new NSString(bindings.NSUndoManagerWillCloseUndoGroupNotification);
+}
 
 enum
 {
 	NSUndoCloseGroupingRunLoopOrdering = 350000
 }
 
-static this ()
-{
-	NSUndoManagerCheckpointNotification = new NSString(bindings.NSUndoManagerCheckpointNotification);
-	NSUndoManagerWillUndoChangeNotification = new NSString(bindings.NSUndoManagerWillUndoChangeNotification);
-	NSUndoManagerWillRedoChangeNotification = new NSString(bindings.NSUndoManagerWillRedoChangeNotification);
-	NSUndoManagerDidUndoChangeNotification = new NSString(bindings.NSUndoManagerDidUndoChangeNotification);
-	NSUndoManagerDidRedoChangeNotification = new NSString(bindings.NSUndoManagerDidRedoChangeNotification);
-	NSUndoManagerDidOpenUndoGroupNotification = new NSString(bindings.NSUndoManagerDidOpenUndoGroupNotification);
-	NSUndoManagerWillCloseUndoGroupNotification = new NSString(bindings.NSUndoManagerWillCloseUndoGroupNotification);
-}
-
 class NSUndoManager : NSObject
 {
-	mixin ObjcWrap;
-
+	mixin (ObjcWrap);
+	
+	this ()
+	{
+		super(typeof(this).alloc.init.objcObject);
+	}
+	
+	typeof(this) init ()
+	{
+		return invokeObjcSelf!(typeof(this), "init");
+	}
+	
 	void beginUndoGrouping ()
 	{
 		return invokeObjcSelf!(void, "beginUndoGrouping");