Added AQTree-- a tree class based on CFTree.

Tree/AQTree.h

@@ -0,0 +1,88 @@
+/*
+ * AQTree.h
+ * aqtoolkit
+ * 
+ * Created by Jim Dovey on 26/2/2010.
+ * 
+ * Copyright (c) 2010 Jim Dovey
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 
+ * Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ * 
+ * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 
+ * Neither the name of the project's author nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
+ * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#import <Foundation/Foundation.h>
+#import "iPhoneNonatomic.h"
+
+@interface AQTree : NSObject <NSCoding, NSFastEnumeration>
+{
+    AQTree * _parent;           // not retained
+    AQTree * _sibling;          // not retained
+    AQTree * _child;            // all children are retained
+    AQTree * _rightmostChild;   // not retained
+
+    id       _content;
+
+    unsigned long   _mutationsCounter;  // used for fast enumeration mutation detection
+}
+
+- (id) initWithContent: (id) contentObject;
+@property (NS_NONATOMIC_IPHONEONLY retain) id content;
+
+@property (NS_NONATOMIC_IPHONEONLY readonly) AQTree * parent;
+@property (NS_NONATOMIC_IPHONEONLY readonly) AQTree * sibling;
+@property (NS_NONATOMIC_IPHONEONLY readonly) AQTree * firstChild;
+@property (NS_NONATOMIC_IPHONEONLY readonly) NSUInteger numberOfChildren;
+
+- (AQTree *) childAtIndex: (NSUInteger) index;
+- (NSArray *) children;
+- (void) makeChildrenPerformSelector: (SEL) selector;       // performs selector on the AQTree objects
+- (void) makeChildObjectsPerformSelector: (SEL) selector;   // performs selector on the content objects
+
+@property (NS_NONATOMIC_IPHONEONLY readonly) AQTree * root;
+
+- (void) prependChild: (AQTree *) newChild;
+- (void) appendChild: (AQTree *) newChild;
+
+- (void) insertSibling: (AQTree *) newSibling;
+
+- (void) removeFromParent;
+- (void) removeAllChildren;
+
+- (void) sortChildrenUsingDescriptors: (NSArray *) descriptors;
+
+- (NSEnumerator *) childEnumerator;
+
+#if NS_BLOCKS_AVAILABLE
+- (void) enumerateChildrenUsingBlock: (void (^)(AQTree * tree, NSUInteger idx, BOOL *stop)) block;
+- (void) enumerateChildrenWithOptions: (NSEnumerationOptions) opts usingBlock: (void (^)(AQTree * tree, NSUInteger idx, BOOL * stop)) block;
+
+- (void) sortChildrenUsingComparator: (NSComparator) cmptr;
+#endif
+
+@end