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diff --git a/docs/examples/xml/phonebook/phonebook3.scala b/docs/examples/xml/phonebook/phonebook3.scala
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+++ b/docs/examples/xml/phonebook/phonebook3.scala
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+/* examples/xml/phonebook/phonebook3.scala */
+package phonebook
+
+object phonebook3 {
+
+  import scala.xml.{Elem, Node, Text}
+  import scala.xml.Utility.view
+  import scala.xml.PrettyPrinter
+  import Node.NoAttributes
+
+  /* finds entry for Name, Where, changes it, or adds if not present */
+  def change ( phonebook: Node, Name: String, Where: String, newPhone: String ) = {
+
+    /** returns true if this element's first child is the right 'name'
+     *  x is treated a if it was a singleton sequence here.
+     */
+    def hasName ( x: Seq[Node] ) = x(0).child.elements.next match {
+      case <name>{ Text(Name) }</name> => true
+      case _                           => false
+    }
+
+    /** returns true if this element has the right 'where' attribute
+     *  y is treated a if it was a singleton sequence here.
+     *  n.attribute(s) is the same as n.attributes.get(s)
+     */
+    def hasWhere ( y: Node ) = y.attribute("where") match {
+      case Some(Text(Where)) => true
+      case None              => false
+    }
+
+    /** returns true if this element has the right 'where' attribute
+     *  the apply method of MetaData (n.attributes) returns raw a
+     *  sequence of nodes.
+     */
+    def hasWhere2 ( y: Node ) = y.attributes("where") match {
+      case null        => false
+      case Text(Where) => true
+      case _           => false
+    }
+
+
+    /** walks through tree, returns changed/copied updated tree  */
+    def copyOrChange ( ch: Iterator[Node] ):List[Node] = {
+        for( val c <- ch ) yield c match {
+
+        case x @ <entry>{ ch1 @ _* }</entry> if hasName( x ) =>
+          val it = ch1.elements;
+          val nameElem:Seq[Node] = it.next;             // grab 'name' element
+          val ch2 = nameElem concat copyOrChange( it ); // concat with updated seq
+
+          if( ch1 == ch2 ) // not present: add as first entry
+
+            <entry>
+              <name>{ Name }</name>
+              <phone where={ Where }>{ newPhone }</phone>
+              { ch1 }
+            </entry>
+
+          else             // was present and changed
+
+            <entry>
+              { ch2 }
+            </entry>
+
+        case y @ <phone>{ _* }</phone> if hasWhere( y ) =>
+            Console.println("c = "+c);
+            <phone where={ Where }>{ newPhone }</phone>
+
+          case _ =>
+            Console.println("c = "+c);
+            Console.println("c.attributes= "+c.attributes);
+                            c
+
+        }
+    }.toList ; // for ... yield ... returns Iterator, convert to list
+
+    // decompose phonebook, apply updates
+    phonebook match {
+      case <phonebook>{ ch @ _* }</phonebook> =>
+        <phonebook>{ copyOrChange( ch.elements ) }</phonebook>
+    }
+
+  }
+
+  val pb2 =
+    change( phonebook1.labPhoneBook, "John", "work", "+41 55 555 55 55" );
+
+  val pp = new PrettyPrinter( 80, 5 );
+
+  def main( args:Array[String] ) = {
+    Console.println("---before---");
+    Console.println( pp.format( phonebook1.labPhoneBook ));
+    Console.println("---after---");
+    Console.println( pp.format( pb2 ));
+  }
+}