X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=lily%2Fmusic-wrapper-iterator.cc;h=b6d0d616564c2e655464da371d642e94f5dfcf88;hb=3f141d50d558df9fdfe08cc97b1bc910c0833e86;hp=e81aced76f453c7578cd321d104391b22e0db08d;hpb=c659cb200486c2f908703696a1b2873e78c8160a;p=lilypond.git

diff --git a/lily/music-wrapper-iterator.cc b/lily/music-wrapper-iterator.cc
index e81aced76f..b6d0d61656 100644
--- a/lily/music-wrapper-iterator.cc
+++ b/lily/music-wrapper-iterator.cc
@@ -1,15 +1,14 @@
-/*   
-  music-wrapper-iterator.cc --  implement Music_wrapper_iterator
-  
+/*
+  music-wrapper-iterator.cc -- implement Music_wrapper_iterator
+
   source file of the GNU LilyPond music typesetter
-  
-  (c) 1998--2004 Han-Wen Nienhuys <hanwen@cs.uu.nl>
- */
 
+  (c) 1998--2007 Han-Wen Nienhuys <hanwen@xs4all.nl>
+*/
 
 #include "music-wrapper-iterator.hh"
-
 #include "music-wrapper.hh"
+#include "music.hh"
 
 Music_wrapper_iterator::Music_wrapper_iterator ()
 {
@@ -19,7 +18,8 @@ Music_wrapper_iterator::Music_wrapper_iterator ()
 void
 Music_wrapper_iterator::do_quit ()
 {
-  child_iter_->quit ();
+  if (child_iter_)
+    child_iter_->quit ();
 }
 
 void
@@ -30,17 +30,20 @@ Music_wrapper_iterator::derived_mark () const
 }
 
 void
-Music_wrapper_iterator::derived_substitute (Context *f,Context *t) 
+Music_wrapper_iterator::derived_substitute (Context *f, Context *t)
 {
   if (child_iter_)
-    child_iter_->substitute_outlet (f,t);
+    child_iter_->substitute_outlet (f, t);
 }
 
 void
 Music_wrapper_iterator::construct_children ()
 {
-  Music * m =  dynamic_cast<Music_wrapper const*> (get_music ())-> element ();  
-  child_iter_ = unsmob_iterator (get_iterator (m));
+  Music *my_music = get_music ();
+  Music *child = unsmob_music (my_music->get_property ("element"));
+  child_iter_ = (child)
+    ? unsmob_iterator (get_iterator (child))
+    : 0;
 }
 
 bool
@@ -49,24 +52,20 @@ Music_wrapper_iterator::ok () const
   return child_iter_ && child_iter_->ok ();
 }
 
-
 void
 Music_wrapper_iterator::process (Moment m)
 {
-  child_iter_->process (m);
+  if (child_iter_)
+    child_iter_->process (m);
 }
 
-
 Moment
 Music_wrapper_iterator::pending_moment () const
 {
-  return child_iter_->pending_moment ();
-}
-
-Music_iterator*
-Music_wrapper_iterator::try_music_in_children (Music *m) const
-{
-  return child_iter_->try_music (m);
+  if (child_iter_)
+    return child_iter_->pending_moment ();
+  else
+    return Music_iterator::pending_moment ();
 }
 
 IMPLEMENT_CTOR_CALLBACK (Music_wrapper_iterator);
@@ -74,5 +73,5 @@ IMPLEMENT_CTOR_CALLBACK (Music_wrapper_iterator);
 bool
 Music_wrapper_iterator::run_always () const
 {
-  return child_iter_->run_always ();
+  return (child_iter_ &&  child_iter_->run_always ());
 }