lily/context-scheme.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 1998--2011 Jan Nieuwenhuizen <janneke@gnu.org>
   5   Han-Wen Nienhuys <hanwen@xs4all.nl>
   6
   7   LilyPond is free software: you can redistribute it and/or modify
   8   it under the terms of the GNU General Public License as published by
   9   the Free Software Foundation, either version 3 of the License, or
  10   (at your option) any later version.
  11
  12   LilyPond is distributed in the hope that it will be useful,
  13   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15   GNU General Public License for more details.
  16
  17   You should have received a copy of the GNU General Public License
  18   along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "context.hh"
  22 #include "context-def.hh"
  23 #include "dispatcher.hh"
  24
  25 LY_DEFINE (ly_context_current_moment,
  26            "ly:context-current-moment",
  27            1, 0, 0, (SCM context),
  28            "Return the current moment of @var{context}.")
  29 {
  30   Context *tr = unsmob_context (context);
  31
  32   LY_ASSERT_SMOB (Context, context, 1);
  33
  34   return tr->now_mom ().smobbed_copy ();
  35 }
  36
  37 LY_DEFINE (ly_context_id, "ly:context-id",
  38            1, 0, 0, (SCM context),
  39            "Return the ID string of @var{context},"
  40            " i.e., for @code{\\context Voice = \"one\" @dots{}}"
  41            " return the string @code{one}.")
  42 {
  43   Context *tr = unsmob_context (context);
  44
  45   LY_ASSERT_SMOB (Context, context, 1);
  46
  47   return ly_string2scm (tr->id_string ());
  48 }
  49
  50 LY_DEFINE (ly_context_name, "ly:context-name",
  51            1, 0, 0, (SCM context),
  52            "Return the name of @var{context},"
  53            " i.e., for @code{\\context Voice = \"one\" @dots{}}"
  54            " return the symbol @code{Voice}.")
  55 {
  56   LY_ASSERT_SMOB (Context, context, 1);
  57
  58   Context *tr = unsmob_context (context);
  59
  60   return ly_symbol2scm (tr->context_name ().c_str ());
  61 }
  62
  63 LY_DEFINE (ly_context_grob_definition, "ly:context-grob-definition",
  64            2, 0, 0, (SCM context, SCM name),
  65            "Return the definition of @var{name} (a symbol) within"
  66            " @var{context} as an alist.")
  67 {
  68   Context *tr = unsmob_context (context);
  69
  70   LY_ASSERT_SMOB (Context, context, 1);
  71   LY_ASSERT_TYPE (ly_is_symbol, name, 2);
  72
  73   return updated_grob_properties (tr, name);
  74 }
  75
  76 LY_DEFINE (ly_context_pushpop_property, "ly:context-pushpop-property",
  77            3, 1, 0, (SCM context, SCM grob, SCM eltprop, SCM val),
  78            "Do a single @code{\\override} or @code{\\revert} operation"
  79            " in @var{context}.  The grob definition @var{grob} is extended"
  80            " with @var{eltprop} (if @var{val} is specified) or reverted"
  81            " (if unspecified).")
  82 {
  83   Context *tg = unsmob_context (context);
  84
  85   LY_ASSERT_SMOB (Context, context, 1);
  86   LY_ASSERT_TYPE (ly_is_symbol, grob, 2);
  87   LY_ASSERT_TYPE (ly_is_symbol, eltprop, 3);
  88
  89   execute_pushpop_property (tg, grob, eltprop, val);
  90
  91   return SCM_UNSPECIFIED;
  92 }
  93
  94 LY_DEFINE (ly_context_property, "ly:context-property",
  95            2, 1, 0, (SCM context, SCM sym, SCM def),
  96            "Return the value for property @var{sym} in @var{context}."
  97            " If @var{def} is given, and property value is @code{'()},"
  98            " return @var{def}.")
  99 {
 100   LY_ASSERT_SMOB (Context, context, 1);
 101   LY_ASSERT_TYPE (ly_is_symbol, sym, 2);
 102
 103   Context *t = unsmob_context (context);
 104   SCM result = t->internal_get_property (sym);
 105   return def != SCM_UNDEFINED && scm_is_null (result) ? def : result;
 106 }
 107
 108 LY_DEFINE (ly_context_set_property_x, "ly:context-set-property!",
 109            3, 0, 0, (SCM context, SCM name, SCM val),
 110            "Set value of property @var{name} in context @var{context}"
 111            " to @var{val}.")
 112 {
 113   LY_ASSERT_SMOB (Context, context, 1);
 114   LY_ASSERT_TYPE (ly_is_symbol, name, 2);
 115
 116   Context *tr = unsmob_context (context);
 117
 118   tr->set_property (name, val);
 119
 120   return SCM_UNSPECIFIED;
 121 }
 122
 123 LY_DEFINE (ly_context_property_where_defined, "ly:context-property-where-defined",
 124            2, 0, 0, (SCM context, SCM name),
 125            "Return the context above @var{context}"
 126            " where @var{name} is defined.")
 127 {
 128   LY_ASSERT_SMOB (Context, context, 1);
 129   LY_ASSERT_TYPE (ly_is_symbol, name, 2);
 130
 131   Context *tr = unsmob_context (context);
 132
 133   SCM val;
 134   tr = tr->where_defined (name, &val);
 135   if (tr)
 136     return tr->self_scm ();
 137
 138   return SCM_EOL;
 139 }
 140
 141 LY_DEFINE (ly_context_unset_property, "ly:context-unset-property", 2, 0, 0,
 142            (SCM context, SCM name),
 143            "Unset value of property @var{name} in context @var{context}.")
 144 {
 145   LY_ASSERT_SMOB (Context, context, 1);
 146   LY_ASSERT_TYPE (ly_is_symbol, name, 2);
 147   Context *tr = unsmob_context (context);
 148
 149   tr->unset_property (name);
 150   return SCM_UNSPECIFIED;
 151 }
 152
 153 LY_DEFINE (ly_context_parent, "ly:context-parent",
 154            1, 0, 0, (SCM context),
 155            "Return the parent of @var{context}, @code{#f} if none.")
 156 {
 157   LY_ASSERT_SMOB (Context, context, 1);
 158   Context *tr = unsmob_context (context);
 159
 160   tr = tr->get_parent_context ();
 161   if (tr)
 162     return tr->self_scm ();
 163   else
 164     return SCM_BOOL_F;
 165 }
 166
 167 /* FIXME: todo: should support translator IDs, and creation? */
 168 LY_DEFINE (ly_context_find, "ly:context-find",
 169            2, 0, 0, (SCM context, SCM name),
 170            "Find a parent of @var{context} that has name or alias @var{name}."
 171            "  Return @code{#f} if not found.")
 172 {
 173   LY_ASSERT_SMOB (Context, context, 1);
 174   LY_ASSERT_TYPE (ly_is_symbol, name, 2);
 175   Context *tr = unsmob_context (context);
 176
 177   while (tr)
 178     {
 179       if (tr->is_alias (name))
 180         return tr->self_scm ();
 181       tr = tr->get_parent_context ();
 182     }
 183
 184   return SCM_BOOL_F;
 185 }
 186
 187 LY_DEFINE (ly_context_now, "ly:context-now",
 188            1, 0, 0, (SCM context),
 189            "Return @code{now-moment} of context @var{context}.")
 190 {
 191   LY_ASSERT_SMOB (Context, context, 1);
 192   Context *ctx = unsmob_context (context);
 193   return ctx->now_mom ().smobbed_copy ();
 194 }
 195
 196 LY_DEFINE (ly_context_event_source, "ly:context-event-source",
 197            1, 0, 0, (SCM context),
 198            "Return @code{event-source} of context @var{context}.")
 199 {
 200   LY_ASSERT_SMOB (Context, context, 1);
 201   Context *ctx = unsmob_context (context);
 202   return ctx->event_source ()->self_scm ();
 203 }
 204
 205 LY_DEFINE (ly_context_events_below, "ly:context-events-below",
 206            1, 0, 0, (SCM context),
 207            "Return a @code{stream-distributor} that distributes all events"
 208            " from @var{context} and all its subcontexts.")
 209 {
 210   LY_ASSERT_SMOB (Context, context, 1);
 211   Context *ctx = unsmob_context (context);
 212   return ctx->events_below ()->self_scm ();
 213 }