diff -r 3a6ce43d99b1 -r ff7f9510b0d6 src/Pure/library.scala
--- a/src/Pure/library.scala	Sun Aug 22 20:25:15 2010 +0200
+++ b/src/Pure/library.scala	Sun Aug 22 22:09:14 2010 +0200
@@ -79,7 +79,7 @@
     def next(): CharSequence =
       state match {
         case Some((s, i)) => { state = next_chunk(i); s }
-        case None => throw new NoSuchElementException("next on empty iterator")
+        case None => Iterator.empty.next()
       }
   }