-/*
- context.cc -- implement Context
+/*
+ context.cc -- implement Context
source file of the GNU LilyPond music typesetter
- (c) 2004 Han-Wen Nienhuys <hanwen@xs4all.nl>
-
+ (c) 2004--2006 Han-Wen Nienhuys <hanwen@xs4all.nl>
*/
-#include "translator-group.hh"
-#include "context-def.hh"
#include "context.hh"
-#include "warn.hh"
-#include "music-output-def.hh"
-#include "scm-hash.hh"
-#include "main.hh"
+
+#include "context-def.hh"
+#include "dispatcher.hh"
+#include "international.hh"
#include "ly-smobs.icc"
+#include "main.hh"
+#include "output-def.hh"
+#include "profile.hh"
+#include "program-option.hh"
+#include "scm-hash.hh"
#include "score-context.hh"
+#include "translator-group.hh"
+#include "warn.hh"
bool
Context::is_removable () const
{
- return context_list_ == SCM_EOL && ! iterator_count_ &&
- !dynamic_cast<Score_context const*> (this)
- ;
+ return context_list_ == SCM_EOL && ! iterator_count_
+ && !dynamic_cast<Global_context const *> (daddy_context_);
}
-
void
Context::check_removal ()
{
- for (SCM p = context_list_; gh_pair_p (p); p = gh_cdr (p))
+ for (SCM p = context_list_; scm_is_pair (p); p = scm_cdr (p))
{
- Context *trg = unsmob_context (ly_car (p));
+ Context *ctx = unsmob_context (scm_car (p));
- trg->check_removal ();
- if (trg->is_removable ())
+ ctx->check_removal ();
+ if (ctx->is_removable ())
{
- recurse_down_translators (trg, &Translator::finalize, false);
- remove_context (trg);
+ recurse_over_translators (ctx, &Translator::finalize,
+ &Translator_group::finalize,
+ UP);
+ send_stream_event (ctx, "RemoveContext", 0, 0);
}
}
}
-Context::Context (Context const&)
+Context::Context (Context const &src)
+ : key_manager_ (src.key_manager_)
{
assert (false);
}
-Scheme_hash_table*
+Scheme_hash_table *
Context::properties_dict () const
{
return Scheme_hash_table::unsmob (properties_scm_);
}
void
-Context::add_context (Context*t)
+Context::add_context (Context *child)
{
- SCM ts = t->self_scm ();
- context_list_ = gh_append2 (context_list_,
- gh_cons (ts, SCM_EOL));
-
- t->daddy_context_ = this;
- if (!t->init_)
- {
- t->init_ = true;
-
- scm_gc_unprotect_object (ts);
- Context_def * td = unsmob_context_def (t->definition_);
-
- /*
- this can not move before add_context(), because \override
- operations require that we are in the hierarchy.
- */
- td->apply_default_property_operations (t);
-
- recurse_down_translators (t, &Translator::initialize, true);
- }
+ context_list_ = ly_append2 (context_list_,
+ scm_cons (child->self_scm (), SCM_EOL));
+
+ child->daddy_context_ = this;
+ this->events_below_->register_as_listener (child->events_below_);
}
-Context::Context ()
+
+Context::Context (Object_key const *key)
+ : key_manager_ (key)
{
daddy_context_ = 0;
- init_ = false;
- iterator_count_ = 0;
- implementation_ = SCM_EOL;
+ aliases_ = SCM_EOL;
+ iterator_count_ = 0;
+ implementation_ = 0;
properties_scm_ = SCM_EOL;
accepts_list_ = SCM_EOL;
context_list_ = SCM_EOL;
definition_ = SCM_EOL;
-
+ definition_mods_ = SCM_EOL;
+ event_source_ = 0;
+ events_below_ = 0;
+
smobify_self ();
- Scheme_hash_table *tab = new Scheme_hash_table ;
- properties_scm_ = tab->self_scm ();
- scm_gc_unprotect_object (tab->self_scm ());
+ Scheme_hash_table *tab = new Scheme_hash_table;
+ properties_scm_ = tab->unprotect ();
+ event_source_ = new Dispatcher ();
+ event_source_->unprotect ();
+ events_below_ = new Dispatcher ();
+ events_below_->unprotect ();
+
+ /*
+ UGH UGH
+ const correctness.
+ */
+ key_manager_.unprotect();
}
+/* TODO: this shares code with find_create_context (). */
Context *
-Context::find_existing_context (SCM n, String id)
+Context::create_unique_context (SCM name, string id, SCM operations)
{
- if ((is_alias (n) && (id_string_ == id || id.is_empty ())) || n == ly_symbol2scm ("Current"))
- return this;
+ /*
+ Don't create multiple score contexts.
+ */
+ Global_context *gthis = dynamic_cast<Global_context *> (this);
+ if (gthis && gthis->get_score_context ())
+ return gthis->get_score_context ()->create_unique_context (name, id, operations);
- Context* r = 0;
- for (SCM p = context_list_; !r && gh_pair_p (p); p = ly_cdr (p))
+ /*
+ TODO: use accepts_list_.
+ */
+ vector<Context_def*> path
+ = unsmob_context_def (definition_)->path_to_acceptable_context (name, get_output_def ());
+
+ if (path.size ())
{
- Context * t = unsmob_context (ly_car (p));
-
- r = dynamic_cast<Context*> (t)->find_existing_context (n, id);
+ Context *current = this;
+
+ // start at 1. The first one (index 0) will be us.
+ for (vsize i = 0; i < path.size (); i++)
+ {
+ SCM ops = SCM_EOL;
+ string id_str = "\\new";
+ if (i == path.size () - 1)
+ {
+ ops = operations;
+ id_str = id;
+ }
+ current = current->create_context (path[i],
+ id_str,
+ ops);
+ }
+
+ return current;
}
- return r;
+ /*
+ Don't go up to Global_context, because global goes down to
+ Score_context
+ */
+ Context *ret = 0;
+ if (daddy_context_ && !dynamic_cast<Global_context *> (daddy_context_))
+ ret = daddy_context_->create_unique_context (name, id, operations);
+ else
+ {
+ warning (_f ("can't find or create new `%s'",
+ ly_symbol2string (name).c_str ()));
+ ret = 0;
+ }
+ return ret;
}
-
-Context*
-Context::find_create_context (SCM n, String id,
- SCM operations)
+Context *
+Context::find_create_context (SCM n, string id, SCM operations)
{
- Context * existing = find_existing_context (n,id);
- if (existing)
+ /*
+ Don't create multiple score contexts.
+ */
+ Global_context *gthis = dynamic_cast<Global_context *> (this);
+ if (gthis && gthis->get_score_context ())
+ return gthis->get_score_context ()->find_create_context (n, id, operations);
+
+ if (Context *existing = find_context_below (this, n, id))
return existing;
if (n == ly_symbol2scm ("Bottom"))
{
- Context* tg = get_default_interpreter ();
- tg->id_string_ = id;
+ Context *tg = get_default_interpreter ();
return tg;
}
/*
TODO: use accepts_list_.
- */
- Link_array<Context_def> path
+ */
+ vector<Context_def*> path
= unsmob_context_def (definition_)->path_to_acceptable_context (n, get_output_def ());
if (path.size ())
{
- Context * current = this;
+ Context *current = this;
// start at 1. The first one (index 0) will be us.
- for (int i=0; i < path.size (); i++)
+ for (vsize i = 0; i < path.size (); i++)
{
SCM ops = (i == path.size () -1) ? operations : SCM_EOL;
- Context * new_group
- = path[i]->instantiate (ops);
-
+ string this_id = "";
if (i == path.size () -1)
- {
- new_group->id_string_ = id;
- }
+ this_id = id;
- current->add_context (new_group);
- apply_property_operations (new_group, ops);
-
- current = new_group;
+ current = current->create_context (path[i],
+ this_id,
+ ops);
}
return current;
}
+ /*
+ Don't go up to Global_context, because global goes down to
+ Score_context
+ */
Context *ret = 0;
- if (daddy_context_)
+ if (daddy_context_ && !dynamic_cast<Global_context *> (daddy_context_))
ret = daddy_context_->find_create_context (n, id, operations);
else
{
- warning (_f ("Cannot find or create `%s' called `%s'",
- ly_symbol2string (n).to_str0 (), id));
- ret =0;
+ warning (_f ("can't find or create `%s' called `%s'",
+ ly_symbol2string (n).c_str (), id));
+ ret = 0;
}
return ret;
}
+IMPLEMENT_LISTENER (Context, acknowledge_infant);
+void
+Context::acknowledge_infant (SCM sev)
+{
+ infant_event_ = unsmob_stream_event (sev);
+}
+
+IMPLEMENT_LISTENER (Context, set_property_from_event);
+void
+Context::set_property_from_event (SCM sev)
+{
+ Stream_event *ev = unsmob_stream_event (sev);
+
+ SCM sym = ev->get_property ("symbol");
+ if (scm_is_symbol (sym))
+ {
+ SCM val = ev->get_property ("value");
+ bool ok = true;
+ if (val != SCM_EOL)
+ ok = type_check_assignment (sym, val, ly_symbol2scm ("translation-type?"));
+ if (ok)
+ internal_set_property (sym, val);
+ }
+}
+
+IMPLEMENT_LISTENER (Context, unset_property_from_event);
+void
+Context::unset_property_from_event (SCM sev)
+{
+ Stream_event *ev = unsmob_stream_event (sev);
+
+ SCM sym = ev->get_property ("symbol");
+ type_check_assignment (sym, SCM_EOL, ly_symbol2scm ("translation-type?"));
+ unset_property (sym);
+}
+
+/*
+ Creates a new context from a CreateContext event, and sends an
+ AnnounceNewContext event to this context.
+*/
+IMPLEMENT_LISTENER (Context, create_context_from_event);
+void
+Context::create_context_from_event (SCM sev)
+{
+ Stream_event *ev = unsmob_stream_event (sev);
+
+ string id = ly_scm2string (ev->get_property ("id"));
+ SCM ops = ev->get_property ("ops");
+ SCM type_scm = ev->get_property ("type");
+ string type = ly_symbol2string (type_scm);
+ Object_key const *key = key_manager_.get_context_key (now_mom(), type, id);
+
+ vector<Context_def*> path
+ = unsmob_context_def (definition_)->path_to_acceptable_context (type_scm, get_output_def ());
+ if (path.size () != 1)
+ {
+ programming_error (_f ("Invalid CreateContext event: Cannot create %s context", type.c_str ()));
+ return;
+ }
+ Context_def *cdef = path[0];
+
+ Context *new_context = cdef->instantiate (ops, key);
+
+ new_context->id_string_ = id;
+
+ /* Register various listeners:
+ - Make the new context hear events that universally affect contexts
+ - connect events_below etc. properly */
+ /* We want to be the first ones to hear our own events. Therefore, wait
+ before registering events_below_ */
+ new_context->event_source ()->
+ add_listener (GET_LISTENER (new_context->create_context_from_event),
+ ly_symbol2scm ("CreateContext"));
+ new_context->event_source ()->
+ add_listener (GET_LISTENER (new_context->remove_context),
+ ly_symbol2scm ("RemoveContext"));
+ new_context->event_source ()->
+ add_listener (GET_LISTENER (new_context->change_parent),
+ ly_symbol2scm ("ChangeParent"));
+ new_context->event_source ()->
+ add_listener (GET_LISTENER (new_context->set_property_from_event),
+ ly_symbol2scm ("SetProperty"));
+ new_context->event_source ()->
+ add_listener (GET_LISTENER (new_context->unset_property_from_event),
+ ly_symbol2scm ("UnsetProperty"));
+
+ new_context->events_below_->register_as_listener (new_context->event_source_);
+ this->add_context (new_context);
+
+ new_context->unprotect ();
+
+ Context_def *td = unsmob_context_def (new_context->definition_);
+
+ /* This cannot move before add_context (), because \override
+ operations require that we are in the hierarchy. */
+ td->apply_default_property_operations (new_context);
+ apply_property_operations (new_context, ops);
+
+ send_stream_event (this, "AnnounceNewContext", 0,
+ ly_symbol2scm ("context"), new_context->self_scm (),
+ ly_symbol2scm ("creator"), sev);
+}
+
+Context *
+Context::create_context (Context_def *cdef,
+ string id,
+ SCM ops)
+{
+ infant_event_ = 0;
+ /* TODO: This is fairly misplaced. We can fix this when we have taken out all
+ iterator specific stuff from the Context class */
+ event_source_->
+ add_listener (GET_LISTENER (acknowledge_infant),
+ ly_symbol2scm ("AnnounceNewContext"));
+ /* The CreateContext creates a new context, and sends an announcement of the
+ new context through another event. That event will be stored in
+ infant_event_ to create a return value. */
+ send_stream_event (this, "CreateContext", 0,
+ ly_symbol2scm ("ops"), ops,
+ ly_symbol2scm ("type"), cdef->get_context_name (),
+ ly_symbol2scm ("id"), scm_makfrom0str (id.c_str ()));
+ event_source_->
+ remove_listener (GET_LISTENER (acknowledge_infant),
+ ly_symbol2scm ("AnnounceNewContext"));
+
+ assert (infant_event_);
+ SCM infant_scm = infant_event_->get_property ("context");
+ Context *infant = unsmob_context (infant_scm);
+
+ if (!infant || infant->get_parent_context () != this)
+ {
+ programming_error ("create_context: can't locate newly created context");
+ return 0;
+ }
+
+ return infant;
+}
+
/*
Default child context as a SCM string, or something else if there is
none.
*/
SCM
-default_child_context_name (Context const *tg)
+Context::default_child_context_name () const
{
- return gh_pair_p (tg->accepts_list_)
- ? ly_car (scm_last_pair (tg->accepts_list_))
+ return scm_is_pair (accepts_list_)
+ ? scm_car (accepts_list_)
: SCM_EOL;
}
-
bool
Context::is_bottom_context () const
{
- return !gh_symbol_p (default_child_context_name (this));
+ return !scm_is_symbol (default_child_context_name ());
}
-Context*
+Context *
Context::get_default_interpreter ()
{
if (!is_bottom_context ())
{
- SCM nm = default_child_context_name (this);
- SCM st = get_output_def ()->find_context_def (nm);
+ SCM nm = default_child_context_name ();
+ SCM st = find_context_def (get_output_def (), nm);
+ string name = ly_symbol2string (nm);
Context_def *t = unsmob_context_def (st);
if (!t)
{
- warning (_f ("can't find or create: `%s'", ly_symbol2string (nm).to_str0 ()));
+ warning (_f ("can't find or create: `%s'", name.c_str ()));
t = unsmob_context_def (this->definition_);
}
- Context *tg = t->instantiate (SCM_EOL);
- add_context (tg);
- if (!tg->is_bottom_context ())
- return tg->get_default_interpreter ();
- else
- return tg;
+
+ Context *tg = create_context (t, "", SCM_EOL);
+ return tg->get_default_interpreter ();
}
return this;
}
/*
PROPERTIES
- */
-Context*
-Context::where_defined (SCM sym) const
+*/
+Context *
+Context::where_defined (SCM sym, SCM *value) const
{
- if (properties_dict ()->contains (sym))
- {
- return (Context*)this;
- }
+#ifndef NDEBUG
+ if (profile_property_accesses)
+ note_property_access (&context_property_lookup_table, sym);
+#endif
+
+ if (properties_dict ()->try_retrieve (sym, value))
+ return (Context *)this;
- return (daddy_context_) ? daddy_context_->where_defined (sym) : 0;
+ return (daddy_context_) ? daddy_context_->where_defined (sym, value) : 0;
}
/*
SCM
Context::internal_get_property (SCM sym) const
{
- SCM val =SCM_EOL;
+#ifndef NDEBUG
+ if (profile_property_accesses)
+ note_property_access (&context_property_lookup_table, sym);
+#endif
+
+ SCM val = SCM_EOL;
if (properties_dict ()->try_retrieve (sym, &val))
return val;
if (daddy_context_)
return daddy_context_->internal_get_property (sym);
-
+
return val;
}
+/*
+Called by the send_stream_event macro. props is a 0-terminated array of
+properties and corresponding values, interleaved. This method should not
+be called from any other place than the send_stream_event macro.
+*/
+void
+Context::internal_send_stream_event (SCM type, Input *origin, SCM props[])
+{
+ Stream_event *e = new Stream_event (type, origin);
+ for (int i = 0; props[i]; i += 2)
+ {
+ e->internal_set_property (props[i], props[i+1]);
+ }
+ event_source_->broadcast (e);
+ e->unprotect ();
+}
+
bool
Context::is_alias (SCM sym) const
{
if (sym == ly_symbol2scm ("Bottom")
- && !gh_pair_p (accepts_list_))
+ && !scm_is_pair (accepts_list_))
return true;
- return unsmob_context_def (definition_)->is_alias (sym);
+ if (sym == unsmob_context_def (definition_)->get_context_name ())
+ return true;
+
+ return scm_c_memq (sym, aliases_) != SCM_BOOL_F;
+}
+
+void
+Context::add_alias (SCM sym)
+{
+ aliases_ = scm_cons (sym, aliases_);
}
void
Context::internal_set_property (SCM sym, SCM val)
{
#ifndef NDEBUG
- if (internal_type_checking_global_b)
+ if (do_internal_type_checking_global)
assert (type_check_assignment (sym, val, ly_symbol2scm ("translation-type?")));
#endif
-
+
properties_dict ()->set (sym, val);
}
/*
- TODO: look up to check whether we have inherited var?
- */
+ TODO: look up to check whether we have inherited var?
+*/
void
Context::unset_property (SCM sym)
{
properties_dict ()->remove (sym);
}
-/**
- Remove a context from the hierarchy.
+IMPLEMENT_LISTENER (Context, change_parent);
+void
+Context::change_parent (SCM sev)
+{
+ Stream_event *ev = unsmob_stream_event (sev);
+ Context *to = unsmob_context (ev->get_property ("context"));
+
+ disconnect_from_parent ();
+ to->add_context (this);
+}
+
+/*
+ Die. The next GC sweep should take care of the actual death.
*/
-Context *
-Context::remove_context (Context*trans)
+IMPLEMENT_LISTENER (Context, remove_context);
+void
+Context::remove_context (SCM)
{
- assert (trans);
+ /* ugh, the translator group should listen to RemoveContext events by itself */
+ implementation ()->disconnect_from_context ();
+ disconnect_from_parent ();
+}
- context_list_ = scm_delq_x (trans->self_scm (), context_list_);
- trans->daddy_context_ = 0;
- return trans;
+void
+Context::disconnect_from_parent ()
+{
+ daddy_context_->events_below_->unregister_as_listener (this->events_below_);
+ daddy_context_->context_list_ = scm_delq_x (this->self_scm (), daddy_context_->context_list_);
+ daddy_context_ = 0;
}
/*
ID == "" means accept any ID.
- */
+*/
Context *
-find_context_below (Context * where,
- String type, String id)
+find_context_below (Context *where,
+ SCM type, string id)
{
- if (where->is_alias (ly_symbol2scm (type.to_str0 ())))
+ if (where->is_alias (type))
{
- if (id == "" || where->id_string_ == id)
+ if (id == "" || where->id_string () == id)
return where;
}
-
- Context * found = 0;
- for (SCM s = where->context_list_;
- !found && gh_pair_p (s); s = gh_cdr (s))
+
+ Context *found = 0;
+ for (SCM s = where->children_contexts ();
+ !found && scm_is_pair (s); s = scm_cdr (s))
{
- Context * tr = unsmob_context (gh_car (s));
+ Context *tr = unsmob_context (scm_car (s));
found = find_context_below (tr, type, id);
}
- return found;
+ return found;
}
SCM
Context::properties_as_alist () const
{
- return properties_dict()->to_alist();
+ return properties_dict ()->to_alist ();
}
-String
-Context::context_name () const
+SCM
+Context::context_name_symbol () const
{
- Context_def * td = unsmob_context_def (definition_ );
- return ly_symbol2string (td->get_context_name ());
+ Context_def *td = unsmob_context_def (definition_);
+ return td->get_context_name ();
}
+string
+Context::context_name () const
+{
+ return ly_symbol2string (context_name_symbol ());
+}
-Score_context*
+Score_context *
Context::get_score_context () const
{
- if (Score_context *sc =dynamic_cast<Score_context*> ((Context*)this))
+ if (Score_context *sc = dynamic_cast<Score_context *> ((Context *) this))
return sc;
else if (daddy_context_)
return daddy_context_->get_score_context ();
return 0;
}
-Music_output_def *
+Output_def *
Context::get_output_def () const
{
- return (daddy_context_)
- ? daddy_context_->get_output_def () : 0;
+ return daddy_context_ ? daddy_context_->get_output_def () : 0;
}
-Context::~Context()
+Context::~Context ()
{
-
}
Moment
Context::now_mom () const
{
- return daddy_context_->now_mom();
+ Context const *p = this;
+ while (p->daddy_context_)
+ p = p->daddy_context_;
+
+ return p->now_mom ();
}
int
Context::print_smob (SCM s, SCM port, scm_print_state *)
{
- Context *sc = (Context *) ly_cdr (s);
-
+ Context *sc = (Context *) SCM_CELL_WORD_1 (s);
+
scm_puts ("#<", port);
- scm_puts (classname (sc), port);
- if (Context_def *d=unsmob_context_def (sc->definition_))
+ scm_puts (sc->class_name (), port);
+ if (Context_def *d = unsmob_context_def (sc->definition_))
{
scm_puts (" ", port);
scm_display (d->get_context_name (), port);
}
- if (Context *td=dynamic_cast<Context *> (sc))
+ if (!sc->id_string_.empty ())
{
scm_puts ("=", port);
- scm_puts (td->id_string_.to_str0 (), port);
+ scm_puts (sc->id_string_.c_str (), port);
}
-
scm_puts (" ", port);
- scm_display (sc->implementation_, port);
-
-#if 0
- Translator * tr = unsmob_translator (sc->implementation_);
- if (Translator_group *tg = dynamic_cast<Translator_group*> (tr))
- scm_display (tg->get_simple_trans_list (), port);
-#endif
-
- /*
- don't try to print properties, that is too much hassle.
- */
+
+ scm_display (sc->context_list_, port);
scm_puts (" >", port);
-
+
return 1;
}
+Object_key const *
+Context::get_grob_key (string name)
+{
+ return key_manager_.get_grob_key (now_mom (), name);
+}
+
+Object_key const *
+Context::get_context_key (string name, string id)
+{
+ return key_manager_.get_context_key (now_mom (), name, id);
+}
+
SCM
Context::mark_smob (SCM sm)
{
- Context * me = (Context*) SCM_CELL_WORD_1 (sm);
-
+ Context *me = (Context *) SCM_CELL_WORD_1 (sm);
+ me->key_manager_.gc_mark();
+
scm_gc_mark (me->context_list_);
- scm_gc_mark (me->definition_);
- scm_gc_mark (me->properties_scm_);
+ scm_gc_mark (me->aliases_);
+ scm_gc_mark (me->definition_);
+ scm_gc_mark (me->definition_mods_);
+ scm_gc_mark (me->properties_scm_);
scm_gc_mark (me->accepts_list_);
- scm_gc_mark (me->implementation_);
+ if (me->implementation_)
+ scm_gc_mark (me->implementation_->self_scm ());
+ if (me->event_source_) scm_gc_mark (me->event_source_->self_scm ());
+ if (me->events_below_) scm_gc_mark (me->events_below_->self_scm ());
return me->properties_scm_;
}
IMPLEMENT_SMOBS (Context);
IMPLEMENT_DEFAULT_EQUAL_P (Context);
-IMPLEMENT_TYPE_P(Context,"ly:context?");
+IMPLEMENT_TYPE_P (Context, "ly:context?");
bool
-Context::try_music (Music* m)
+Context::try_music (Music *m)
{
- Translator* t = unsmob_translator (implementation_);
+ Translator_group *t = implementation ();
if (!t)
return false;
-
+
bool b = t->try_music (m);
if (!b && daddy_context_)
b = daddy_context_->try_music (m);
return b;
}
-
-Global_context*
+Global_context *
Context::get_global_context () const
{
- if (dynamic_cast<Global_context *>((Context*) this))
- return dynamic_cast<Global_context *> ((Context*) this);
+ if (dynamic_cast<Global_context *> ((Context *) this))
+ return dynamic_cast<Global_context *> ((Context *) this);
if (daddy_context_)
return daddy_context_->get_global_context ();
- programming_error ("No Global context!");
+ programming_error ("no Global context");
return 0;
}
+
+Context *
+Context::get_parent_context () const
+{
+ return daddy_context_;
+}
+
+void
+Context::clear_key_disambiguations ()
+{
+ if (!use_object_keys)
+ return;
+
+ key_manager_.clear ();
+ for (SCM s = context_list_; scm_is_pair (s); s = scm_cdr (s))
+ unsmob_context (scm_car (s))->clear_key_disambiguations ();
+}
+
+/*
+ Ugh. Where to put this?
+*/
+Rational
+measure_length (Context const *context)
+{
+ SCM l = context->get_property ("measureLength");
+ Rational length (1);
+ if (unsmob_moment (l))
+ length = unsmob_moment (l)->main_part_;
+ return length;
+}
+
+Moment
+measure_position (Context const *context)
+{
+ SCM sm = context->get_property ("measurePosition");
+
+ Moment m = 0;
+ if (unsmob_moment (sm))
+ {
+ m = *unsmob_moment (sm);
+
+ if (m.main_part_ < Rational (0))
+ {
+ Rational length (measure_length (context));
+ while (m.main_part_ < Rational (0))
+ m.main_part_ += length;
+ }
+ }
+
+ return m;
+}
+
+
+void
+set_context_property_on_children (Context *trans, SCM sym, SCM val)
+{
+ trans->internal_set_property (sym, ly_deep_copy (val));
+ for (SCM p = trans->children_contexts (); scm_is_pair (p); p = scm_cdr (p))
+ {
+ Context *trg = unsmob_context (scm_car (p));
+ set_context_property_on_children (trg, sym, ly_deep_copy (val));
+ }
+}
+
+bool
+melisma_busy (Context *tr)
+{
+ SCM melisma_properties = tr->get_property ("melismaBusyProperties");
+ bool busy = false;
+
+ for (; scm_is_pair (melisma_properties);
+ melisma_properties = scm_cdr (melisma_properties))
+ busy = busy || to_boolean (tr->internal_get_property (scm_car (melisma_properties)));
+
+ return busy;
+}