lily/change-iterator.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 1997--2010 Han-Wen Nienhuys <hanwen@xs4all.nl>
   5
   6   LilyPond is free software: you can redistribute it and/or modify
   7   it under the terms of the GNU General Public License as published by
   8   the Free Software Foundation, either version 3 of the License, or
   9   (at your option) any later version.
  10
  11   LilyPond is distributed in the hope that it will be useful,
  12   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14   GNU General Public License for more details.
  15
  16   You should have received a copy of the GNU General Public License
  17   along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "change-iterator.hh"
  21
  22 #include "context.hh"
  23 #include "input.hh"
  24 #include "international.hh"
  25 #include "music.hh"
  26 #include "warn.hh"
  27
  28 void
  29 Change_iterator::error (string reason)
  30 {
  31   string to_type = ly_symbol2string (get_music ()->get_property ("change-to-type"));
  32   string to_id = ly_scm2string (get_music ()->get_property ("change-to-id"));
  33
  34   string warn1 = _f ("cannot change `%s' to `%s'", to_type, to_id)
  35     + ": " + reason;
  36
  37   /*
  38     GUHG!
  39   */
  40   string warn2= "Change_iterator::process (): "
  41     + get_outlet ()->context_name () + " = `"
  42     + get_outlet ()->id_string () + "': ";
  43   warning (warn2);
  44   get_music ()->origin ()->warning (warn1);
  45 }
  46
  47 /*
  48   move to construct_children ?
  49 */
  50 void
  51 Change_iterator::process (Moment m)
  52 {
  53   Context *current = get_outlet ();
  54   Context *last = 0;
  55
  56   SCM to_type = get_music ()->get_property ("change-to-type");
  57   string to_id = ly_scm2string (get_music ()->get_property ("change-to-id"));
  58
  59   /* find the type  of translator that we're changing.
  60
  61   If \translator Staff = bass, then look for Staff = *
  62   */
  63   while (current && !current->is_alias (to_type))
  64     {
  65       last = current;
  66       current = current->get_parent_context ();
  67     }
  68
  69   if (current && current->id_string () == to_id)
  70     {
  71       string msg;
  72       msg += _f ("cannot change, already in translator: %s", to_id);
  73     }
  74
  75   if (current)
  76     if (last)
  77       {
  78         Context *dest = 0;
  79         Context *where = get_outlet ();
  80         while (!dest && where)
  81           {
  82             dest = find_context_below (where, to_type, to_id);
  83             where = where->get_parent_context ();
  84           }
  85
  86         if (dest)
  87           {
  88             send_stream_event (last, "ChangeParent", get_music ()->origin (),
  89                                ly_symbol2scm ("context"), dest->self_scm ());
  90           }
  91         else
  92           /* FIXME: constant error message.  */
  93           get_music ()->origin ()->warning (_ ("cannot find context to switch to"));
  94       }
  95     else
  96       {
  97         /* We could change the current translator's id, but that would make
  98            errors hard to catch.
  99
 100            last->translator_id_string () = get_change
 101            ()->change_to_id_string (); */
 102         error (_f ("not changing to same context type: %s", ly_symbol2string (to_type).c_str ()));
 103       }
 104   else
 105     /* FIXME: uncomprehensable message */
 106     error (_ ("none of these in my family"));
 107
 108   Simple_music_iterator::process (m);
 109 }
 110
 111 IMPLEMENT_CTOR_CALLBACK (Change_iterator);