X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=lily%2Fmusic-wrapper-iterator.cc;h=4ee22d98a13b68f6f5e1595e841be128ca99c485;hb=abf0f7e73103716d60c235fa61d938754d9f3a06;hp=c50a64c7c10f97082658bdaff72fada615b789b1;hpb=8b500afb9431f5471e385fa2eeb8fde868e4fc49;p=lilypond.git

diff --git a/lily/music-wrapper-iterator.cc b/lily/music-wrapper-iterator.cc
index c50a64c7c1..4ee22d98a1 100644
--- a/lily/music-wrapper-iterator.cc
+++ b/lily/music-wrapper-iterator.cc
@@ -1,13 +1,25 @@
 /*
-  music-wrapper-iterator.cc -- implement Music_wrapper_iterator
+  This file is part of LilyPond, the GNU music typesetter.
 
-  source file of the GNU LilyPond music typesetter
+  Copyright (C) 1998--2010 Han-Wen Nienhuys <hanwen@xs4all.nl>
 
-  (c) 1998--2006 Han-Wen Nienhuys <hanwen@xs4all.nl>
+  LilyPond is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  LilyPond is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
 */
 
 #include "music-wrapper-iterator.hh"
 #include "music-wrapper.hh"
+#include "music.hh"
 
 Music_wrapper_iterator::Music_wrapper_iterator ()
 {
@@ -17,7 +29,8 @@ Music_wrapper_iterator::Music_wrapper_iterator ()
 void
 Music_wrapper_iterator::do_quit ()
 {
-  child_iter_->quit ();
+  if (child_iter_)
+    child_iter_->quit ();
 }
 
 void
@@ -39,7 +52,9 @@ Music_wrapper_iterator::construct_children ()
 {
   Music *my_music = get_music ();
   Music *child = unsmob_music (my_music->get_property ("element"));
-  child_iter_ = unsmob_iterator (get_iterator (child));
+  child_iter_ = (child)
+    ? unsmob_iterator (get_iterator (child))
+    : 0;
 }
 
 bool
@@ -51,13 +66,17 @@ Music_wrapper_iterator::ok () const
 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 ();
+  if (child_iter_)
+    return child_iter_->pending_moment ();
+  else
+    return Music_iterator::pending_moment ();
 }
 
 IMPLEMENT_CTOR_CALLBACK (Music_wrapper_iterator);
@@ -65,5 +84,5 @@ 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 ());
 }