Replace remaining uses of unsmob_xxx with Xxx::unsmob

[lilypond.git] / lily / property-iterator.cc

diff --git a/lily/property-iterator.cc b/lily/property-iterator.cc
index d7afdde905e1aa678f78a98241853278f8b3369a..c7cb8108b0b214f8e2c5e1f4209c430c0f37f472 100644 (file)
--- a/lily/property-iterator.cc
+++ b/lily/property-iterator.cc
@@ -61,21 +61,40 @@ Property_iterator::process (Moment mom)
 }
 
 void
-Property_unset_iterator::process (Moment m)
+Property_unset_iterator::process (Moment mom)
 {
-  SCM sym = get_music ()->get_property ("symbol");
-  send_stream_event (get_outlet (), "UnsetProperty", get_music ()->origin (),
-                     ly_symbol2scm ("symbol"), sym);
+  Context *o = get_outlet ();
+  Music *m = get_music ();
+  bool once = to_boolean (m->get_property ("once"));
+  SCM symbol = m->get_property ("symbol");
+  SCM previous_value = SCM_UNDEFINED;
+  if (once) {
+    Context *w = o->where_defined (symbol, &previous_value);
+    if (o != w)
+      previous_value = SCM_UNDEFINED;
+  }
+  send_stream_event (o, "UnsetProperty", m->origin (),
+                     ly_symbol2scm ("symbol"), symbol);
 
-  Simple_music_iterator::process (m);
+  /* For \once \unset install a finalization hook to reset the property to the
+   * previous value after the timestep */
+  if (once && !SCM_UNBNDP (previous_value))
+    {
+      Global_context *tg = get_outlet ()->get_global_context ();
+      tg->add_finalization (scm_list_4 (Property_iterator::once_finalization_proc,
+                                        o->self_scm (), m->self_scm (),
+                                        previous_value));
+    }
+
+  Simple_music_iterator::process (mom);
 }
 
 MAKE_SCHEME_CALLBACK (Property_iterator, once_finalization, 3);
 SCM
 Property_iterator::once_finalization (SCM ctx, SCM music, SCM previous_value)
 {
-  Music *m = unsmob_music (music);
-  Context *c = unsmob_context (ctx);
+  Music *m = Music::unsmob (music);
+  Context *c = Context::unsmob (ctx);
 
   // Do not use UnsetProperty, which sets the default, but rather
   // cache the value before the \once \set command and restore it now
@@ -144,8 +163,8 @@ MAKE_SCHEME_CALLBACK (Push_property_iterator, once_finalization, 2);
 SCM
 Push_property_iterator::once_finalization (SCM ctx, SCM music)
 {
-  Music *mus = unsmob_music (music);
-  Context *c = unsmob_context (ctx);
+  Music *mus = Music::unsmob (music);
+  Context *c = Context::unsmob (ctx);
 
   SCM sym = mus->get_property ("symbol");
   if (check_grob (mus, sym))