--- a/dstep/foundation/NSExpression.d	Mon Aug 03 15:31:48 2009 +0200
+++ b/dstep/foundation/NSExpression.d	Sun Jan 03 22:06:11 2010 +0100
@@ -7,12 +7,15 @@
 module dstep.foundation.NSExpression;
 
 import dstep.foundation.NSArray;
-import dstep.foundation.NSMutableDictionary;
+import dstep.foundation.NSCoder;
+import dstep.foundation.NSDictionary;
+import dstep.foundation.NSObjCRuntime;
 import dstep.foundation.NSObject;
 import dstep.foundation.NSPredicate;
 import dstep.foundation.NSString;
+import dstep.foundation.NSZone;
 import dstep.objc.bridge.Bridge;
-import dstep.objc.objc : id;
+import dstep.objc.objc;
 
 alias NSUInteger NSExpressionType;
 
@@ -32,61 +35,71 @@
 
 class NSExpression : NSObject, INSCoding, INSCopying
 {
-	mixin ObjcWrap;
+	mixin (ObjcWrap);
+	
+	this ()
+	{
+		super(typeof(this).alloc.init.objcObject);
+	}
+	
+	typeof(this) init ()
+	{
+		return invokeObjcSelf!(typeof(this), "init");
+	}
 
 	static NSExpression expressionForConstantValue (Object obj)
 	{
-		return invokeObjcSelfClass!(NSExpression, "expressionForConstantValue:", Object)(obj);
+		return invokeObjcSuperClass!(NSExpression, "expressionForConstantValue:", Object)(obj);
 	}
 
 	static NSExpression expressionForEvaluatedObject ()
 	{
-		return invokeObjcSelfClass!(NSExpression, "expressionForEvaluatedObject");
+		return invokeObjcSuperClass!(NSExpression, "expressionForEvaluatedObject");
 	}
 
 	static NSExpression expressionForVariable (NSString string)
 	{
-		return invokeObjcSelfClass!(NSExpression, "expressionForVariable:", NSString)(string);
+		return invokeObjcSuperClass!(NSExpression, "expressionForVariable:", NSString)(string);
 	}
 
 	static NSExpression expressionForKeyPath (NSString keyPath)
 	{
-		return invokeObjcSelfClass!(NSExpression, "expressionForKeyPath:", NSString)(keyPath);
+		return invokeObjcSuperClass!(NSExpression, "expressionForKeyPath:", NSString)(keyPath);
 	}
 
 	static NSExpression expressionForFunction (NSString name, NSArray parameters)
 	{
-		return invokeObjcSelfClass!(NSExpression, "expressionForFunction:arguments:", NSString, NSArray)(name, parameters);
+		return invokeObjcSuperClass!(NSExpression, "expressionForFunction:arguments:", NSString, NSArray)(name, parameters);
 	}
 
 	static NSExpression expressionForAggregate (NSArray subexpressions)
 	{
-		return invokeObjcSelfClass!(NSExpression, "expressionForAggregate:", NSArray)(subexpressions);
+		return invokeObjcSuperClass!(NSExpression, "expressionForAggregate:", NSArray)(subexpressions);
 	}
 
 	static NSExpression expressionForUnionSet (NSExpression left, NSExpression right)
 	{
-		return invokeObjcSelfClass!(NSExpression, "expressionForUnionSet:with:", NSExpression, NSExpression)(left, right);
+		return invokeObjcSuperClass!(NSExpression, "expressionForUnionSet:with:", NSExpression, NSExpression)(left, right);
 	}
 
 	static NSExpression expressionForIntersectSet (NSExpression left, NSExpression right)
 	{
-		return invokeObjcSelfClass!(NSExpression, "expressionForIntersectSet:with:", NSExpression, NSExpression)(left, right);
+		return invokeObjcSuperClass!(NSExpression, "expressionForIntersectSet:with:", NSExpression, NSExpression)(left, right);
 	}
 
 	static NSExpression expressionForMinusSet (NSExpression left, NSExpression right)
 	{
-		return invokeObjcSelfClass!(NSExpression, "expressionForMinusSet:with:", NSExpression, NSExpression)(left, right);
+		return invokeObjcSuperClass!(NSExpression, "expressionForMinusSet:with:", NSExpression, NSExpression)(left, right);
 	}
 
 	static NSExpression expressionForSubquery (NSExpression expression, NSString variable, Object predicate)
 	{
-		return invokeObjcSelfClass!(NSExpression, "expressionForSubquery:usingIteratorVariable:predicate:", NSExpression, NSString, Object)(expression, variable, predicate);
+		return invokeObjcSuperClass!(NSExpression, "expressionForSubquery:usingIteratorVariable:predicate:", NSExpression, NSString, Object)(expression, variable, predicate);
 	}
 
 	static NSExpression expressionForFunction (NSExpression target, NSString name, NSArray parameters)
 	{
-		return invokeObjcSelfClass!(NSExpression, "expressionForFunction:selectorName:arguments:", NSExpression, NSString, NSArray)(target, name, parameters);
+		return invokeObjcSuperClass!(NSExpression, "expressionForFunction:selectorName:arguments:", NSExpression, NSString, NSArray)(target, name, parameters);
 	}
 
 	Object initWithExpressionType (uint type)
@@ -96,13 +109,7 @@
 
 	this (uint type)
 	{
-		objcObject = Bridge.invokeObjcClassMethod!(id, "alloc")(objcClass);
-		id result = Bridge.invokeObjcMethod!(id, "initWithExpressionType:", uint)(objcObject, type);
-
-		if (result)
-			objcObject = ret;
-
-		dObject = this;
+		typeof(this).alloc.initWithExpressionType(type);
 	}
 
 	uint expressionType ()
@@ -180,13 +187,7 @@
 
 	this (NSCoder aDecoder)
 	{
-		objcObject = Bridge.invokeObjcClassMethod!(id, "alloc")(objcClass);
-		id result = Bridge.invokeObjcMethod!(id, "initWithCoder:", NSCoder)(objcObject, aDecoder);
-
-		if (result)
-			objcObject = ret;
-
-		dObject = this;
+		typeof(this).alloc.initWithCoder(aDecoder);
 	}
 
 	Object copyWithZone (NSZone* zone)