2 This file is part of LilyPond, the GNU music typesetter.
4 Copyright (C) 2004--2014 Han-Wen Nienhuys <hanwen@xs4all.nl>
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.
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.
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/>.
21 #include "engraver.hh"
22 #include "global-context.hh"
23 #include "grob-properties.hh"
24 #include "international.hh"
27 #include "simple-closure.hh"
30 #include "unpure-pure-container.hh"
34 like execute_general_pushpop_property(), but typecheck
35 grob_property_path and context_property.
38 general_pushpop_property (Context *context,
40 SCM grob_property_path,
43 if (!scm_is_symbol (context_property)
44 || !scm_is_symbol (scm_car (grob_property_path)))
46 warning (_ ("need symbol arguments for \\override and \\revert"));
47 if (do_internal_type_checking_global)
51 Grob_property_info (context, context_property).pushpop
52 (grob_property_path, new_value);
56 typecheck_grob (SCM symbol, SCM value)
58 if (Unpure_pure_container *upc = Unpure_pure_container::unsmob (value))
59 return typecheck_grob (symbol, upc->unpure_part ())
60 && typecheck_grob (symbol, upc->pure_part ());
61 return ly_is_procedure (value)
62 || Simple_closure::is_smob (value)
63 || type_check_assignment (symbol, value, ly_symbol2scm ("backend-type?"));
66 class Grob_properties : public Simple_smob<Grob_properties>
70 static const char type_p_name_[];
72 friend class Grob_property_info;
73 friend SCM ly_make_grob_properties (SCM);
74 // alist_ may contain unexpanded nested overrides
76 // based_on_ is the cooked_ value from the next higher context that
79 // cooked_ is a version of alist_ where nested overrides have been
82 // cooked_from_ is the value of alist_ from which the expansion has
85 // nested_ is a count of nested overrides in alist_
88 Grob_properties (SCM alist, SCM based_on) :
89 alist_ (alist), based_on_ (based_on),
90 // if the constructor was called with lists possibly containing
91 // partial overrides, we would need to initialize with based_on in
92 // order to trigger an initial update. But this should never
93 // happen, so we initialize straight with alist.
94 cooked_ (alist), cooked_from_ (alist), nested_ (0) { }
97 const char Grob_properties::type_p_name_[] = "ly:grob-properties?";
100 Grob_properties::mark_smob ()
102 scm_gc_mark (alist_);
103 scm_gc_mark (based_on_);
104 scm_gc_mark (cooked_);
108 LY_DEFINE (ly_make_grob_properties, "ly:make-grob-properties",
109 1, 0, 0, (SCM alist),
110 "This packages the given property list @var{alist} in"
111 " a grob property container stored in a context property"
112 " with the name of a grob.")
114 LY_ASSERT_TYPE (ly_is_list, alist, 1);
115 return Grob_properties (alist, SCM_EOL).smobbed_copy ();
120 Grob_property_info::find ()
124 SCM res = SCM_UNDEFINED;
125 if (Context *c = context_->where_defined (symbol_, &res))
127 return Grob_property_info (c, symbol_, Grob_properties::unsmob (res));
128 props_ = Grob_properties::unsmob (res);
133 Grob_property_info::check ()
137 SCM res = SCM_UNDEFINED;
138 if (context_->here_defined (symbol_, &res))
139 props_ = Grob_properties::unsmob (res);
144 Grob_property_info::create ()
146 // Using scm_hashq_create_handle_x would seem like the one-lookup
147 // way to create a handle if it does not exist yet. However, we
148 // need to check that there is a corresponding grob in this
149 // particular output first, and we have to do this in the global
150 // context. By far the most frequent case will be that a
151 // Grob_properties for this context already exists, so we optimize
152 // for that and only check the global handle when the local
153 // context is pristine.
156 SCM current_context_val = SCM_EOL;
157 Context *g = context_->get_global_context ();
159 return false; // Context is probably dead
162 Don't mess with MIDI.
165 || !g->here_defined (symbol_, ¤t_context_val))
168 Grob_properties *def = Grob_properties::unsmob (current_context_val);
172 programming_error ("Grob definition expected");
176 // We create the new Grob_properties from the default definition
177 // since this is what we have available right now. It may or may
178 // not be accurate since we don't take into account any
179 // prospective overrides in intermediate contexts. If there are
180 // any, they will be factored in when `updated' is being called.
181 SCM props = Grob_properties (def->alist_, def->alist_).smobbed_copy ();
182 context_->set_property (symbol_, props);
183 props_ = Grob_properties::unsmob (props);
188 Grob descriptions (ie. alists with layout properties) are
189 represented as a (ALIST . BASED-ON) pair, where BASED-ON is the
190 alist defined in a parent context. BASED-ON should always be a tail
193 Push or pop (depending on value of VAL) a single entry from a
194 translator property list by name of PROP. GROB_PROPERTY_PATH
195 indicates nested alists, eg. '(beamed-stem-lengths details)
198 Grob_property_info::push (SCM grob_property_path, SCM new_value)
201 Don't mess with MIDI.
206 SCM symbol = scm_car (grob_property_path);
207 SCM rest = scm_cdr (grob_property_path);
208 if (scm_is_pair (rest))
210 // poor man's typechecking
211 if (typecheck_grob (symbol, nested_create_alist (rest, new_value))) {
212 props_->alist_ = scm_acons (grob_property_path, new_value, props_->alist_);
218 /* it's tempting to replace the head of the list if it's the same
219 property. However, we have to keep this info around, in case we have to
223 if (typecheck_grob (symbol, new_value))
224 props_->alist_ = scm_acons (symbol, new_value, props_->alist_);
228 Revert the property given by property_path.
231 Grob_property_info::pop (SCM grob_property_path)
236 SCM current_alist = props_->alist_;
237 SCM daddy = props_->based_on_;
239 if (!scm_is_pair (grob_property_path)
240 || !scm_is_symbol (scm_car (grob_property_path)))
242 programming_error ("Grob property path should be list of symbols.");
246 if (scm_is_pair (scm_cdr (grob_property_path)))
248 SCM old_alist = current_alist;
249 current_alist = evict_from_alist (grob_property_path, current_alist, daddy);
250 if (scm_is_eq (old_alist, current_alist))
255 current_alist = evict_from_alist (scm_car (grob_property_path),
256 current_alist, daddy);
258 if (scm_is_eq (current_alist, daddy))
260 assert (props_->nested_ == 0);
262 context_->unset_property (symbol_);
265 props_->alist_ = current_alist;
268 Convenience: a push/pop grob property using a single grob_property
272 execute_pushpop_property (Context *context,
277 Grob_property_info (context, grob).pushpop (scm_list_1 (grob_property), new_value);
281 PRE_INIT_OPS is in the order specified, and hence must be reversed.
284 apply_property_operations (Context *tg, SCM pre_init_ops)
286 for (SCM s = pre_init_ops; scm_is_pair (s); s = scm_cdr (s))
288 SCM entry = scm_car (s);
289 SCM type = scm_car (entry);
290 entry = scm_cdr (entry);
292 if (type == ly_symbol2scm ("push"))
294 SCM context_prop = scm_car (entry);
295 SCM val = scm_cadr (entry);
296 SCM grob_prop_path = scm_cddr (entry);
297 Grob_property_info (tg, context_prop).push (grob_prop_path, val);
299 else if (type == ly_symbol2scm ("pop"))
301 SCM context_prop = scm_car (entry);
302 SCM grob_prop_path = scm_cdr (entry);
303 Grob_property_info (tg, context_prop).pop (grob_prop_path);
305 else if (type == ly_symbol2scm ("assign"))
306 tg->set_property (scm_car (entry), scm_cadr (entry));
307 else if (type == ly_symbol2scm ("apply"))
308 scm_apply_1 (scm_car (entry), tg->self_scm (), scm_cdr (entry));
309 else if (type == ly_symbol2scm ("unset"))
310 tg->unset_property (scm_car (entry));
315 Return the object alist for SYM, checking if its base in enclosing
316 contexts has changed. The alist is updated if necessary.
318 SCM Grob_property_info::updated ()
320 assert (scm_is_symbol (symbol_));
322 Grob_property_info where = find ();
327 Context *dad = where.context_->get_parent_context ();
330 = dad ? Grob_property_info (dad, symbol_).updated () : SCM_EOL;
332 SCM based_on = where.props_->based_on_;
333 SCM alist = where.props_->alist_;
334 if (!scm_is_eq (based_on, daddy_props))
336 where.props_->based_on_ = daddy_props;
337 alist = partial_list_copy (alist, based_on, daddy_props);
338 where.props_->alist_ = alist;
340 if (scm_is_eq (where.props_->cooked_from_, alist))
341 return where.props_->cooked_;
342 where.props_->cooked_from_ = alist;
343 where.props_->cooked_ = nalist_to_alist (alist, where.props_->nested_);
344 return where.props_->cooked_;