Issue 5167/6: Changes: show \markup xxx = ... \etc assignments

[lilypond.git] / lily / stanza-number-engraver.cc

diff --git a/lily/stanza-number-engraver.cc b/lily/stanza-number-engraver.cc
index 2618274a055dd0ddf41d70bb3d6649070a36b0ff..4b7eaa5a8a3e760e199f3270246e55a622a12bc8 100644 (file)
--- a/lily/stanza-number-engraver.cc
+++ b/lily/stanza-number-engraver.cc
@@ -1,40 +1,57 @@
 /*
-  lyric-number-engraver.cc -- implement Stanza_number_engraver
+  This file is part of LilyPond, the GNU music typesetter.
 
-  source file of the GNU LilyPond music typesetter
+  Copyright (C) 2000--2015 Han-Wen Nienhuys <hanwen@xs4all.nl>, Glen Prideaux <glenprideaux@iname.com>
 
-  (c) 2000--2005 Han-Wen Nienhuys <hanwen@cs.uu.nl>, Glen Prideaux <glenprideaux@iname.com>
+  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 "engraver.hh"
 #include "side-position-interface.hh"
+#include "text-interface.hh"
+#include "item.hh"
 
 class Stanza_number_engraver : public Engraver
 {
   Item *text_;
 
-  /*
-    This is naughty, since last_stanza_ may be GCd from under us.  But
-    since we don't look at the contents, we are/should be (knock on
-    wood) OK.
-  */
   SCM last_stanza_;
 public:
   TRANSLATOR_DECLARATIONS (Stanza_number_engraver);
-  PRECOMPUTED_VIRTUAL void process_music ();
-  PRECOMPUTED_VIRTUAL void stop_translation_timestep ();
-  DECLARE_ACKNOWLEDGER(lyric_syllable);
+  void process_music ();
+  virtual void derived_mark () const;
+  void stop_translation_timestep ();
+  void acknowledge_lyric_syllable (Grob_info);
 };
 
+void
+Stanza_number_engraver::derived_mark () const
+{
+  scm_gc_mark (last_stanza_);
+}
+
 /*
   TODO: should make engraver that collects all the stanzas on a higher
   level, and then groups them to the side. Stanza numbers should be
   all aligned.
 */
 
-Stanza_number_engraver::Stanza_number_engraver ()
+Stanza_number_engraver::Stanza_number_engraver (Context *c)
+  : Engraver (c)
 {
   text_ = 0;
+  last_stanza_ = SCM_EOL;
 }
 
 void
@@ -42,7 +59,8 @@ Stanza_number_engraver::process_music ()
 {
   SCM stanza = get_property ("stanza");
 
-  if (scm_is_string (stanza) && stanza != last_stanza_)
+  if (Text_interface::is_markup (stanza)
+      && !scm_is_eq (stanza, last_stanza_))
     {
       last_stanza_ = stanza;
 
@@ -55,9 +73,7 @@ void
 Stanza_number_engraver::acknowledge_lyric_syllable (Grob_info inf)
 {
   if (text_)
-    {
-      Side_position_interface::add_support (text_, inf.grob ());
-    }
+    Side_position_interface::add_support (text_, inf.grob ());
 }
 
 void
@@ -68,10 +84,22 @@ Stanza_number_engraver::stop_translation_timestep ()
 
 #include "translator.icc"
 
-ADD_ACKNOWLEDGER(Stanza_number_engraver,lyric_syllable);
+void
+Stanza_number_engraver::boot ()
+{
+  ADD_ACKNOWLEDGER (Stanza_number_engraver, lyric_syllable);
+}
+
 ADD_TRANSLATOR (Stanza_number_engraver,
-               /* descr */ "",
-               /* creats*/ "StanzaNumber",
-               /* accepts */ "",
-               /* reads */ "stanza",
-               /* write */ "");
+                /* doc */
+                "Engrave stanza numbers.",
+
+                /* create */
+                "StanzaNumber ",
+
+                /* read */
+                "stanza ",
+
+                /* write */
+                ""
+               );