lily/change-iterator.cc

   1 /*
   2   change-iterator.cc -- implement Change_iterator
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c)  1997--2002 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7 */
   8
   9 #include "change-iterator.hh"
  10 #include "translator-group.hh"
  11 #include "music.hh"
  12 #include "warn.hh"
  13
  14
  15
  16 void
  17 Change_iterator::error (String reason)
  18 {
  19   String to_type = ly_scm2string (get_music ()->get_mus_property ("change-to-type"));
  20   String to_id =  ly_scm2string (get_music ()->get_mus_property ("change-to-id"));
  21
  22   String warn1 = _f ("can't change `%s' to `%s'", to_type, to_id)
  23     + ": " + reason;
  24   /*
  25     GUHG!
  26    */
  27   String warn2= "Change_iterator::process (): "
  28     + report_to ()->type_string_ + " = `"
  29     + report_to ()->id_string_ + "': ";
  30   warning (warn2);
  31   get_music ()->origin ()->warning (warn1);
  32 }
  33
  34 /*
  35   move to construct_children ?
  36  */
  37 void
  38 Change_iterator::process (Moment m)
  39 {
  40   Translator_group * current = report_to ();
  41   Translator_group * last = 0;
  42
  43   String to_type = ly_scm2string (get_music ()->get_mus_property ("change-to-type"));
  44   String to_id =  ly_scm2string (get_music ()->get_mus_property ("change-to-id"));
  45
  46
  47   /* find the type  of translator that we're changing.
  48
  49      If \translator Staff = bass, then look for Staff = *
  50    */
  51   while (current && current->type_string_ != to_type)
  52     {
  53       last = current;
  54       current = current->daddy_trans_;
  55     }
  56
  57   if (current && current->id_string_ == to_id)
  58     {
  59       String msg;
  60       msg += _ ("Can't switch translators, I'm there already");
  61     }
  62
  63   if (current)
  64     if (last)
  65       {
  66         Translator_group * dest =
  67           report_to ()->find_create_translator (to_type, to_id);
  68         current->remove_translator (last);
  69         dest->add_used_group_translator (last);
  70       }
  71     else
  72       {
  73         /*
  74           We could change the current translator's id, but that would make
  75           errors hard to catch
  76
  77            last->translator_id_string_  = get_change ()->change_to_id_string_;
  78         */
  79         error (_ ("I'm one myself"));
  80       }
  81   else
  82     error (_ ("none of these in my family"));
  83   Simple_music_iterator::process (m);
  84 }
  85
  86
  87
  88 IMPLEMENT_CTOR_CALLBACK (Change_iterator);