Index: /CKEditor/trunk/_source/core/dom/node.js
===================================================================
--- /CKEditor/trunk/_source/core/dom/node.js	(revision 3350)
+++ /CKEditor/trunk/_source/core/dom/node.js	(revision 3351)
@@ -285,46 +285,71 @@
 		},
 
-		getNextSourceNode : function( startFromSibling, nodeType )
-		{
-			var $ = this.$;
-
-			var node = ( !startFromSibling && $.firstChild ) ?
-				$.firstChild :
-				$.nextSibling;
-
-			var parent;
-
-			while ( !node && ( parent = ( parent || $ ).parentNode ) )
-				node = parent.nextSibling;
+		getNextSourceNode : function( startFromSibling, nodeType, guard )
+		{
+			var node = ( !startFromSibling && this.getFirst && this.getFirst() ) || this.getNext(),
+				parent;
+
+			// If "guard" is a node, transform it in a function.
+			if ( guard && !guard.call )
+			{
+				var guardNode = guard;
+				guard = function( node )
+				{
+					return !node.equals( guardNode );
+				}
+			}
+
+			while ( !node && ( parent = ( parent || this ).getParent() ) )
+			{
+				if ( guard && guard( parent ) === false )
+					return null;
+
+				node = parent.getNext();
+			}
 
 			if ( !node )
 				return null;
 
-			if ( nodeType && nodeType != node.nodeType )
+			if ( guard && guard( node ) === false )
+				return null;
+
+			if ( nodeType && nodeType != node.type )
 				return arguments.callee.call( { $ : node }, false, nodeType );
 
-			return new CKEDITOR.dom.node( node );
-		},
-
-		getPreviousSourceNode : function( startFromSibling, nodeType )
-		{
-			var $ = this.$;
-
-			var node = ( !startFromSibling && $.lastChild ) ?
-				$.lastChild :
-				$.previousSibling;
-
-			var parent;
-
-			while ( !node && ( parent = ( parent || $ ).parentNode ) )
-				node = parent.previousSibling;
+			return node;
+		},
+
+		getPreviousSourceNode : function( startFromSibling, nodeType, guard )
+		{
+			var node = ( !startFromSibling && this.getLast && this.getLast() ) || this.getPrevious(),
+				parent;
+
+			if ( guard && !guard.call )
+			{
+				var guardNode = guard;
+				guard = function( node )
+				{
+					return !node.equals( guardNode );
+				}
+			}
+
+			while ( !node && ( parent = ( parent || this ).getParent() ) )
+			{
+				if ( guard && guard( parent ) === false )
+					return null;
+
+				node = parent.getPrevious();
+			}
 
 			if ( !node )
 				return null;
 
-			if ( nodeType && node.nodeType != nodeType )
+			if ( guard && guard( node ) === false )
+				return null;
+
+			if ( nodeType && node.type != nodeType )
 				return arguments.callee.call( { $ : node }, false, nodeType );
 
-			return new CKEDITOR.dom.node( node );
+			return node;
 		},
 
Index: /CKEditor/trunk/_source/core/dom/walker.js
===================================================================
--- /CKEditor/trunk/_source/core/dom/walker.js	(revision 3351)
+++ /CKEditor/trunk/_source/core/dom/walker.js	(revision 3351)
@@ -0,0 +1,223 @@
+/*
+Copyright (c) 2003-2009, CKSource - Frederico Knabben. All rights reserved.
+For licensing, see LICENSE.html or http://ckeditor.com/license
+*/
+
+(function()
+{
+	// This function is to be called under a "walker" instance scope.
+	function iterate( rtl, breakOnFalse )
+	{
+		if ( this._.end )
+			return null;
+
+		var node,
+			type = this.type,
+			getSourceNodeFn = ( rtl ? 'getPreviousSourceNode' : 'getNextSourceNode' );
+
+		var guard = this.guard,
+			endNode = this.endNode;
+
+		if ( endNode )
+		{
+			if ( guard )
+			{
+				var originalGuard;
+				guard = function( node )
+				{
+					if ( node.equals( endNode ) )
+						return false;
+
+					return originalGuard( node );
+				}
+			}
+			else
+				guard = endNode;
+		}
+
+		if ( this.current )
+			node = this.current[ getSourceNodeFn ]( false, type, guard );
+		else if ( this.startInclusive )
+		{
+			node = this.startNode;
+			if ( this.guard && this.guard( node ) === false )
+				node = null;
+		}
+		else
+			node = this.startNode[ getSourceNodeFn ]( true, type, guard );
+
+		while ( node && !this._.end )
+		{
+			this.current = node;
+
+			if ( node == this.endNode && !this.endInclusive )
+				break;
+
+			if ( !this.evaluator && this.evaluator( node ) !== false )
+				return node;
+			else if ( breakOnFalse && this.evaluator )
+				return false;
+
+			node = node[ getSourceNodeFn ]( false, type, guard );
+		}
+
+		this.end();
+		return this.current = null;
+	}
+
+	function iterateToLast( rtl )
+	{
+		var node, last;
+
+		while ( node = iterate.call( this, rtl ) )
+			last = node;
+
+		return last;
+	}
+
+	CKEDITOR.dom.walker = CKEDITOR.tools.createClass(
+	{
+		/**
+		 * Utility class to "walk" inside a DOM tree starting from a specific
+		 * node. Each step in the walk can be preciselly controlled.
+		 * @constructor
+		 * @param {CKEDITOR.dom.node} startNode The node from wich the walk
+		 *		will start.
+		 * @param {CKEDITOR.dom.node} [endNode] The last node to be considered
+		 *		in the walk. No more nodes are retrieved after touching or
+		 *		passing it.
+		 */
+		$ : function( startNode, endNode )
+		{
+			/**
+			 * The node from which start walking.
+			 * @type {CKEDITOR.dom.node}
+			 */
+			this.startNode = startNode;
+
+			/**
+			 * The end boundary node of the walk.
+			 * @type {CKEDITOR.dom.node}
+			 */
+			this.endNode = endNode;
+
+			/**
+			 * Indicates that the start node is to be included in the walk.
+			 * @name CKEDITOR.pluginDefinition.prototype.startInclusive
+			 * @property
+			 * @type Boolean
+			 * @default false
+			 */
+			// this.startInclusive = false;
+
+			/**
+			 * Indicates that the end node is to be included in the walk.
+			 * @name CKEDITOR.pluginDefinition.prototype.endInclusive
+			 * @property
+			 * @type Boolean
+			 * @default false
+			 */
+			// this.endInclusive = false;
+
+			/**
+			 * A function executed for every matched node, to check whether
+			 * it's to be considered into the walk or not. If not provided, all
+			 * matched nodes are considered good.
+			 * If the function returns "false" the node is ignored.
+			 * @name CKEDITOR.pluginDefinition.prototype.evaluator
+			 * @property
+			 * @type Function
+			 */
+			// this.evaluator = null;
+
+			/**
+			 * A function executed for every node the walk pass by to check
+			 * whether the walk is to be finished. It's called when both
+			 * entering and exiting nodes, as well as for the matched nodes.
+			 * If this function returns "false", the walking ends and no more
+			 * nodes are evaluated.
+			 * @name CKEDITOR.pluginDefinition.prototype.guard
+			 * @property
+			 * @type Function
+			 */
+			// this.guard = null;
+
+			/** @private */
+			this._ = {};
+		},
+
+		proto :
+		{
+			/**
+			 * Stop walking. No more nodes are retrieved if this function gets
+			 * called.
+			 */
+			end : function()
+			{
+				this._.end = 1;
+			},
+
+			/**
+			 * Retrieves the next node (at right).
+			 * @returns {CKEDITOR.dom.node} The next node or null if no more
+			 *		nodes are available.
+			 */
+			next : function()
+			{
+				return iterate.call( this );
+			},
+
+			/**
+			 * Retrieves the previous node (at left).
+			 * @returns {CKEDITOR.dom.node} The previous node or null if no more
+			 *		nodes are available.
+			 */
+			previous : function()
+			{
+				return iterate.call( this, true );
+			},
+
+			/**
+			 * Executes a full walk forward (to the right), until no more nodes
+			 * are available, returning the last valid node.
+			 * @returns {CKEDITOR.dom.node} The last node at the right or null
+			 *		if no valid nodes are available.
+			 */
+			lastForward : function()
+			{
+				return iterateToLast.call( this );
+			},
+
+			/**
+			 * Executes a full walk backwards (to the left), until no more nodes
+			 * are available, returning the last valid node.
+			 * @returns {CKEDITOR.dom.node} The last node at the left or null
+			 *		if no valid nodes are available.
+			 */
+			lastBackward : function()
+			{
+				return iterateToLast.call( this, true );
+			},
+
+			/**
+			 * Check all nodes at right, executing the evaluation fuction.
+			 * @returns {Boolean} "false" if the evaluator function returned
+			 *		"false" for any of the matched nodes. Otherwise "true".
+			 */
+			checkForward : function()
+			{
+				return iterate.call( this, false, true ) !== false;
+			},
+
+			/**
+			 * Check all nodes at left, executing the evaluation fuction.
+			 * @returns {Boolean} "false" if the evaluator function returned
+			 *		"false" for any of the matched nodes. Otherwise "true".
+			 */
+			checkBackward : function()
+			{
+				return iterate.call( this, true, true ) !== false;
+			}
+		}
+	});
+})();
Index: /CKEditor/trunk/_source/core/loader.js
===================================================================
--- /CKEditor/trunk/_source/core/loader.js	(revision 3350)
+++ /CKEditor/trunk/_source/core/loader.js	(revision 3351)
@@ -41,6 +41,7 @@
 			'core/dom/domobject'	: [ 'core/dom/event' ],
 			'core/dom/domwalker'	: [ 'core/dom/node', 'core/dom/element', 'core/dom/document' ],
-			'core/dom/range'		: [ 'core/dom/document', 'core/dom/documentfragment', 'core/dom/element', 'core/dom/domwalker' ],
+			'core/dom/range'		: [ 'core/dom/document', 'core/dom/documentfragment', 'core/dom/element', 'core/dom/domwalker', 'core/dom/walker' ],
 			'core/dom/text'			: [ 'core/dom/node', 'core/dom/domobject' ],
+			'core/dom/walker'		: [ 'core/dom/node' ],
 			'core/dom/window'		: [ 'core/dom/domobject' ],
 			'core/dtd'				: [ 'core/tools' ],