--- a/src/main/java/jp/ac/u_ryukyu/ie/cr/shoshi/jungle/store/impl/DefaultNodePath.java	Fri Feb 01 00:55:02 2013 +0900
+++ b/src/main/java/jp/ac/u_ryukyu/ie/cr/shoshi/jungle/store/impl/DefaultNodePath.java	Sun Feb 03 19:46:04 2013 +0900
@@ -2,6 +2,7 @@
 
 import java.util.Iterator;
 
+import fj.F;
 import fj.data.List;
 
 import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.store.NodePath;
@@ -20,7 +21,7 @@
 	
 	public DefaultNodePath()
 	{
-		path = List.nil();
+		path = List.list(-1);
 	}
 	
 	private DefaultNodePath(List<Integer> _path)
@@ -38,7 +39,6 @@
 	public DefaultNodePath add(int _pos)
 	{
 		List<Integer> newPath = path.snoc(_pos);
-		
 		return new DefaultNodePath(newPath);
 	}
 
@@ -62,4 +62,22 @@
 	{
 		return path.length();
 	}
+	
+	public List<DefaultNodePath> inits()
+	{
+		List<List<Integer>> inits = path.inits();
+		inits = inits.filter(new F<List<Integer>,Boolean>(){
+			@Override
+			public Boolean f(List<Integer> _init){
+				return _init.length() != 0;
+			}
+		});
+		
+		return inits.map(new F<List<Integer>,DefaultNodePath>(){
+			@Override
+			public DefaultNodePath f(List<Integer> _path){
+				return new DefaultNodePath(_path);
+			}
+		});
+	}
 }

--- a/src/main/java/jp/ac/u_ryukyu/ie/cr/shoshi/jungle/traverser/DefaultTraverser.java	Fri Feb 01 00:55:02 2013 +0900
+++ b/src/main/java/jp/ac/u_ryukyu/ie/cr/shoshi/jungle/traverser/DefaultTraverser.java	Sun Feb 03 19:46:04 2013 +0900
@@ -33,14 +33,17 @@
 			}
 		};
 		
-		Children<T> chs = _root.getChildren();
+		//Children<T> chs = _root.getChildren();
+		Children<T> chs = wrapper;
 		
-		Either<Error,List<Direction<T>>> ret = _traverse(chs,_evaluator);
+		Either<Error,List<Direction<T>>> ret = _traverse(chs,_evaluator,-1);
 		if(ret.isA()){
 			return DefaultEither.newA(ret.a());
 		}
 		
-		final Iterable<Direction<T>> iterable = ret.b();
+		List<Direction<T>> list = ret.b();
+		
+		final Iterable<Direction<T>> iterable = list;
 		final T destination = ret.b().last().getTarget();
 		
 		Traversal<T> traversal = new Traversal<T>(){
@@ -58,9 +61,9 @@
 		return DefaultEither.newB(traversal);
 	}
 	
-	private <T extends TraversableNode<T>> Either<Error,List<Direction<T>>> _traverse(Children<T> _chs,Evaluator _evaluator)
+	private <T extends TraversableNode<T>> Either<Error,List<Direction<T>>> _traverse(Children<T> _chs,Evaluator _evaluator,int _pos)
 	{
-		int pos = 0;
+		int pos = _pos;
 		for(T ch : _chs){
 			Evaluation e = _evaluator.evaluate(ch,pos);
 			Result r = e.result();
@@ -111,7 +114,7 @@
 	private <T extends TraversableNode<T>> Either<Error,List<Direction<T>>> _accept(final T _current,final int _pos,Evaluator _evaluator)
 	{
 		Children<T> chs = _current.getChildren();
-		Either<Error,List<Direction<T>>> either = _traverse(chs,_evaluator);
+		Either<Error,List<Direction<T>>> either = _traverse(chs,_evaluator,0);
 		if(either.isA()){
 			return either;
 		}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/test/java/jp/ac/u_ryukyu/ie/cr/shoshi/jungle/core/impl/treeeditor/DefaultTreeEditorTest.java	Sun Feb 03 19:46:04 2013 +0900
@@ -0,0 +1,120 @@
+package jp.ac.u_ryukyu.ie.cr.shoshi.jungle.core.impl.treeeditor;
+
+import java.nio.ByteBuffer;
+
+import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.store.impl.DefaultNode;
+import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.store.impl.DefaultNodePath;
+import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.store.impl.DefaultTreeEditor;
+import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.store.trasnformer.AppendChildAt;
+import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.transaction.ClonableDefaultNode;
+import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.traverser.DefaultTraverser;
+import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.util.Either;
+import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.util.Error;
+import junit.framework.Assert;
+import junit.framework.TestCase;
+
+public class DefaultTreeEditorTest extends TestCase
+{
+	public DefaultTreeEditor<ClonableDefaultNode> instance()
+	{
+		DefaultTraverser traverser = new DefaultTraverser();
+		ClonableDefaultNode root = new ClonableDefaultNode(new DefaultNode());
+		return new DefaultTreeEditor<ClonableDefaultNode>(root,traverser);
+	}
+	
+	public void testEdittingDoesNotEffectToOtherTree()
+	{
+		
+	}
+	
+	public void testAppendChild()
+	{
+		DefaultTreeEditor<ClonableDefaultNode> instance = instance();
+		DefaultNodePath path = new DefaultNodePath(); // root
+		
+		Either<Error, DefaultTreeEditor<ClonableDefaultNode>> either = instance.appendChild(path,0);
+		if(either.isA()){
+			Assert.fail();
+		}
+		instance = either.b();
+		
+		ClonableDefaultNode node = instance.getRootNode();
+		Assert.assertEquals(1,node.getChildren().size());
+	}
+	
+	public void testDeleteChild()
+	{
+		DefaultTreeEditor<ClonableDefaultNode> instance = instance();
+		DefaultNodePath path = new DefaultNodePath();
+		
+		Either<Error,DefaultTreeEditor<ClonableDefaultNode>> either = instance.appendChild(path,0);
+		if(either.isA()){
+			Assert.fail();
+		}
+		instance = either.b();
+		ClonableDefaultNode node = instance.getRootNode();
+		Assert.assertEquals(1,node.getChildren().size());
+		
+		either = instance.deleteChild(path,0);
+		if(either.isA()){
+			Assert.fail();
+		}
+		instance = either.b();
+		node = instance.getRootNode();
+		Assert.assertEquals(0,node.getChildren().size());
+	}
+	
+	public DefaultTreeEditor<ClonableDefaultNode> testPutAttribute()
+	{
+		DefaultTreeEditor<ClonableDefaultNode> instance = instance();
+		DefaultNodePath path = new DefaultNodePath();
+		
+		String key = "KEY";
+		ByteBuffer value = ByteBuffer.wrap(key.getBytes());
+		
+		Either<Error,DefaultTreeEditor<ClonableDefaultNode>> either = instance.putAttribute(path,key,value);
+		if(either.isA()){
+			Assert.fail();
+		}
+		instance = either.b();
+		
+		ClonableDefaultNode root = instance.getRootNode();
+		ByteBuffer actual = root.getAttributes().get(key);
+		
+		Assert.assertEquals(0,actual.compareTo(value));
+		
+		return instance;
+	}
+	
+	public void testDeleteAttribute()
+	{
+		DefaultTreeEditor<ClonableDefaultNode> instance = testPutAttribute();
+		DefaultNodePath path = new DefaultNodePath();
+		
+		String key = "KEY";
+		
+		Either<Error, DefaultTreeEditor<ClonableDefaultNode>> either = instance.deleteAttribute(path, key);
+		if(either.isA()){
+			Assert.fail();
+		}
+		instance = either.b();
+		
+		ByteBuffer actual = instance.getRootNode().getAttributes().get(key);
+		Assert.assertNull(actual);
+	}
+	
+	public void testEdit()
+	{
+		DefaultTreeEditor<ClonableDefaultNode> instance = instance();
+		DefaultNodePath path = new DefaultNodePath();
+		
+		Either<Error, DefaultTreeEditor<ClonableDefaultNode>> either = instance.edit(path,new AppendChildAt(0));
+		if(either.isA()){
+			Assert.fail();
+		}
+		instance = either.b();
+		
+		ClonableDefaultNode node = instance.getRootNode();
+		Assert.assertEquals(1,node.getChildren().size());
+	}
+}

--- a/src/test/java/jp/ac/u_ryukyu/ie/cr/shoshi/jungle/traverse/TraverserTest.java	Fri Feb 01 00:55:02 2013 +0900
+++ b/src/test/java/jp/ac/u_ryukyu/ie/cr/shoshi/jungle/traverse/TraverserTest.java	Sun Feb 03 19:46:04 2013 +0900
@@ -33,6 +33,7 @@
 	
 		// generate all pattern.
 		List<DefaultNodePath> paths = generatePathPattern(new DefaultNodePath(),0,maxHeight);
+		paths = paths.cons(new DefaultNodePath());
 		
 		for(DefaultNodePath path : paths){
 			DefaultEvaluator evaluator = new DefaultEvaluator(path);
@@ -48,18 +49,14 @@
 			String actual = new String(value.array());
 			Assert.assertEquals(expect,actual);
 			
-			Pair<Integer,NodePath> pop;
-			NodePath estimatedPath = path;
-			DefaultNodePath currentPath = new DefaultNodePath();
+			List<DefaultNodePath> parts = path.inits();
 			
 			for(Direction<TraversableNodeWrapper<ClonableDefaultNode>> d : traversal){
-				pop = estimatedPath.pop();
-				estimatedPath = pop.right();
-				currentPath = currentPath.add(pop.left());
-				
+				DefaultNodePath part = parts.head();
+				parts = parts.tail();
 				value = d.getTarget().getWrapped().getAttributes().get(key);
 				String actualCurrentPathStr = new String(value.array());
-				String expectCurrentPathStr = currentPath.toString();
+				String expectCurrentPathStr = part.toString();
 				Assert.assertEquals(expectCurrentPathStr,actualCurrentPathStr);
 			}
 		}