lily/context-scheme.cc

   1 /*
   2   context-scheme.cc -- Context bindings
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1998--2009 Jan Nieuwenhuizen <janneke@gnu.org>
   7   Han-Wen Nienhuys <hanwen@xs4all.nl>
   8 */
   9
  10 #include "context.hh"
  11 #include "context-def.hh"
  12 #include "dispatcher.hh"
  13
  14 LY_DEFINE (ly_context_id, "ly:context-id",
  15            1, 0, 0, (SCM context),
  16            "Return the ID string of @var{context},"
  17            " i.e., for @code{\\context Voice = one @dots{}}"
  18            " return the string @code{one}.")
  19 {
  20   Context *tr = unsmob_context (context);
  21
  22   LY_ASSERT_SMOB (Context, context, 1);
  23
  24   return ly_string2scm (tr->id_string ());
  25 }
  26
  27 LY_DEFINE (ly_context_name, "ly:context-name",
  28            1, 0, 0, (SCM context),
  29            "Return the name of @var{context},"
  30            " i.e., for @code{\\context Voice = one @dots{}}"
  31            " return the symbol @code{Voice}.")
  32 {
  33   LY_ASSERT_SMOB (Context, context, 1);
  34
  35   Context *tr = unsmob_context (context);
  36
  37   return ly_symbol2scm (tr->context_name ().c_str ());
  38 }
  39
  40 LY_DEFINE (ly_context_grob_definition, "ly:context-grob-definition",
  41            2, 0, 0, (SCM context, SCM name),
  42            "Return the definition of @var{name} (a symbol) within"
  43            " @var{context} as an alist.")
  44 {
  45   Context *tr = unsmob_context (context);
  46
  47   LY_ASSERT_SMOB (Context, context, 1);
  48   LY_ASSERT_TYPE (ly_is_symbol, name, 2);
  49
  50   return updated_grob_properties (tr, name);
  51 }
  52
  53 LY_DEFINE (ly_context_pushpop_property, "ly:context-pushpop-property",
  54            3, 1, 0, (SCM context, SCM grob, SCM eltprop, SCM val),
  55            "Do a single @code{\\override} or @code{\\revert} operation"
  56            " in @var{context}.  The grob definition @var{grob} is extended"
  57            " with @var{eltprop} (if @var{val} is specified) or reverted"
  58            " (if unspecified).")
  59 {
  60   Context *tg = unsmob_context (context);
  61
  62   LY_ASSERT_SMOB (Context, context, 1);
  63   LY_ASSERT_TYPE (ly_is_symbol, grob, 2);
  64   LY_ASSERT_TYPE (ly_is_symbol, eltprop, 3);
  65
  66   execute_pushpop_property (tg, grob, eltprop, val);
  67
  68   return SCM_UNSPECIFIED;
  69 }
  70
  71 LY_DEFINE (ly_context_property, "ly:context-property",
  72            2, 0, 0, (SCM c, SCM name),
  73            "Return the value of @var{name} from context @var{c}.")
  74 {
  75   LY_ASSERT_SMOB (Context, c, 1);
  76   LY_ASSERT_TYPE (ly_is_symbol, name, 2);
  77
  78   Context *t = unsmob_context (c);
  79   return t->internal_get_property (name);
  80 }
  81
  82 LY_DEFINE (ly_context_set_property_x, "ly:context-set-property!",
  83            3, 0, 0, (SCM context, SCM name, SCM val),
  84            "Set value of property @var{name} in context @var{context}"
  85            " to @var{val}.")
  86 {
  87   LY_ASSERT_SMOB (Context, context, 1);
  88   LY_ASSERT_TYPE (ly_is_symbol, name, 2);
  89
  90   Context *tr = unsmob_context (context);
  91
  92   tr->set_property (name, val);
  93
  94   return SCM_UNSPECIFIED;
  95 }
  96
  97 LY_DEFINE (ly_context_property_where_defined, "ly:context-property-where-defined",
  98            2, 0, 0, (SCM context, SCM name),
  99            "Return the context above @var{context}"
 100            " where @var{name} is defined.")
 101 {
 102   LY_ASSERT_SMOB (Context, context, 1);
 103   LY_ASSERT_TYPE (ly_is_symbol, name, 2);
 104
 105   Context *tr = unsmob_context (context);
 106
 107   SCM val;
 108   tr = tr->where_defined (name, &val);
 109   if (tr)
 110     return tr->self_scm ();
 111
 112   return SCM_EOL;
 113 }
 114
 115 LY_DEFINE (ly_context_unset_property, "ly:context-unset-property", 2, 0, 0,
 116            (SCM context, SCM name),
 117            "Unset value of property @var{name} in context @var{context}.")
 118 {
 119   LY_ASSERT_SMOB (Context, context, 1);
 120   LY_ASSERT_TYPE (ly_is_symbol, name, 2);
 121   Context *tr = unsmob_context (context);
 122
 123   tr->unset_property (name);
 124   return SCM_UNSPECIFIED;
 125 }
 126
 127 LY_DEFINE (ly_context_parent, "ly:context-parent",
 128            1, 0, 0, (SCM context),
 129            "Return the parent of @var{context}, @code{#f} if none.")
 130 {
 131   LY_ASSERT_SMOB (Context, context, 1);
 132   Context *tr = unsmob_context (context);
 133
 134   tr = tr->get_parent_context ();
 135   if (tr)
 136     return tr->self_scm ();
 137   else
 138     return SCM_BOOL_F;
 139 }
 140
 141 /* FIXME: todo: should support translator IDs, and creation? */
 142 LY_DEFINE (ly_context_find, "ly:context-find",
 143            2, 0, 0, (SCM context, SCM name),
 144            "Find a parent of @var{context} that has name or alias @var{name}."
 145            "  Return @code{#f} if not found.")
 146 {
 147   LY_ASSERT_SMOB (Context, context, 1);
 148   LY_ASSERT_TYPE (ly_is_symbol, name, 2);
 149   Context *tr = unsmob_context (context);
 150
 151   while (tr)
 152     {
 153       if (tr->is_alias (name))
 154         return tr->self_scm ();
 155       tr = tr->get_parent_context ();
 156     }
 157
 158   return SCM_BOOL_F;
 159 }
 160
 161 LY_DEFINE (ly_context_now, "ly:context-now",
 162            1, 0, 0, (SCM context),
 163            "Return @code{now-moment} of context @var{context}.")
 164 {
 165   LY_ASSERT_SMOB (Context, context, 1);
 166   Context *ctx = unsmob_context (context);
 167   return ctx->now_mom ().smobbed_copy ();
 168 }
 169
 170 LY_DEFINE (ly_context_event_source, "ly:context-event-source",
 171            1, 0, 0, (SCM context),
 172            "Return @code{event-source} of context @var{context}.")
 173 {
 174   LY_ASSERT_SMOB (Context, context, 1);
 175   Context *ctx = unsmob_context (context);
 176   return ctx->event_source ()->self_scm ();
 177 }
 178
 179 LY_DEFINE (ly_context_events_below, "ly:context-events-below",
 180            1, 0, 0, (SCM context),
 181            "Return a @code{stream-distributor} that distributes all events"
 182            " from @var{context} and all its subcontexts.")
 183 {
 184   LY_ASSERT_SMOB (Context, context, 1);
 185   Context *ctx = unsmob_context (context);
 186   return ctx->events_below ()->self_scm ();
 187 }