2 This file is part of LilyPond, the GNU music typesetter.
4 Copyright (C) 2004--2011 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 "international.hh"
25 #include "simple-closure.hh"
30 like execute_general_pushpop_property(), but typecheck
31 grob_property_path and context_property.
34 general_pushpop_property (Context *context,
36 SCM grob_property_path,
39 if (!scm_is_symbol (context_property)
40 || !scm_is_symbol (scm_car (grob_property_path)))
42 warning (_ ("need symbol arguments for \\override and \\revert"));
43 if (do_internal_type_checking_global)
47 sloppy_general_pushpop_property (context, context_property,
48 grob_property_path, new_value);
52 Grob descriptions (ie. alists with layout properties) are
53 represented as a (ALIST . BASED-ON) pair, where BASED-ON is the
54 alist defined in a parent context. BASED-ON should always be a tail
57 Push or pop (depending on value of VAL) a single entry from a
58 translator property list by name of PROP. GROB_PROPERTY_PATH
59 indicates nested alists, eg. '(beamed-stem-lengths details)
62 execute_override_property (Context *context,
64 SCM grob_property_path,
67 SCM current_context_val = SCM_EOL;
69 Context *where = context->where_defined (context_property,
70 ¤t_context_val);
80 SCM base = updated_grob_properties (context, context_property);
81 current_context_val = scm_cons (base, base);
82 context->set_property (context_property, current_context_val);
85 if (!scm_is_pair (current_context_val))
87 programming_error ("Grob definition should be cons");
91 SCM target_alist = scm_car (current_context_val);
94 If the car is a list, the property path comes from a nested override
95 using list syntax inside a \context block
97 if (scm_is_pair (scm_car (grob_property_path)))
98 grob_property_path = scm_car (grob_property_path);
100 SCM symbol = scm_car (grob_property_path);
101 if (scm_is_pair (scm_cdr (grob_property_path)))
103 new_value = nested_property_alist (ly_assoc_get (symbol, target_alist,
105 scm_cdr (grob_property_path),
109 /* it's tempting to replace the head of the list if it's the same
110 property. However, we have to keep this info around, in case we have to
113 target_alist = scm_acons (symbol, new_value, target_alist);
116 if (!ly_is_procedure (new_value)
117 && !is_simple_closure (new_value))
118 ok = type_check_assignment (symbol, new_value,
119 ly_symbol2scm ("backend-type?"));
122 tack onto alist. We can use set_car, since
123 updated_grob_properties () in child contexts will check
124 for changes in the car.
128 scm_set_car_x (current_context_val, target_alist);
133 do a pop (indicated by new_value==SCM_UNDEFINED) or push
136 sloppy_general_pushpop_property (Context *context,
137 SCM context_property,
138 SCM grob_property_path,
141 if (new_value == SCM_UNDEFINED)
142 execute_revert_property (context, context_property,
145 execute_override_property (context, context_property,
151 Revert the property given by property_path.
154 execute_revert_property (Context *context,
155 SCM context_property,
156 SCM grob_property_path)
158 SCM current_context_val = SCM_EOL;
159 if (context->where_defined (context_property, ¤t_context_val)
162 SCM current_alist = scm_car (current_context_val);
163 SCM daddy = scm_cdr (current_context_val);
165 if (!scm_is_pair (grob_property_path)
166 || !scm_is_symbol (scm_car (grob_property_path)))
168 programming_error ("Grob property path should be list of symbols.");
172 SCM symbol = scm_car (grob_property_path);
173 if (scm_is_pair (scm_cdr (grob_property_path)))
175 SCM current_sub_alist = ly_assoc_get (symbol, current_alist, SCM_EOL);
177 = nested_property_revert_alist (current_sub_alist,
178 scm_cdr (grob_property_path));
180 if (scm_is_pair (current_alist)
181 && scm_caar (current_alist) == symbol
182 && current_alist != daddy)
183 current_alist = scm_cdr (current_alist);
185 current_alist = scm_acons (symbol, new_val, current_alist);
186 scm_set_car_x (current_context_val, current_alist);
190 SCM new_alist = evict_from_alist (symbol, current_alist, daddy);
192 if (new_alist == daddy)
193 context->unset_property (context_property);
195 context->set_property (context_property,
196 scm_cons (new_alist, daddy));
201 Convenience: a push/pop grob property using a single grob_property
205 execute_pushpop_property (Context *context,
206 SCM context_property,
210 general_pushpop_property (context, context_property,
211 scm_list_1 (grob_property),
216 PRE_INIT_OPS is in the order specified, and hence must be reversed.
219 apply_property_operations (Context *tg, SCM pre_init_ops)
221 SCM correct_order = scm_reverse (pre_init_ops);
222 for (SCM s = correct_order; scm_is_pair (s); s = scm_cdr (s))
224 SCM entry = scm_car (s);
225 SCM type = scm_car (entry);
226 entry = scm_cdr (entry);
228 if (type == ly_symbol2scm ("push"))
230 SCM context_prop = scm_car (entry);
231 SCM val = scm_cadr (entry);
232 SCM grob_prop_path = scm_cddr (entry);
233 sloppy_general_pushpop_property (tg, context_prop, grob_prop_path, val);
235 else if (type == ly_symbol2scm ("pop"))
237 SCM context_prop = scm_car (entry);
238 SCM val = SCM_UNDEFINED;
239 SCM grob_prop_path = scm_cdr (entry);
240 sloppy_general_pushpop_property (tg, context_prop, grob_prop_path, val);
242 else if (type == ly_symbol2scm ("assign"))
243 tg->set_property (scm_car (entry), scm_cadr (entry));
248 Return the object alist for SYM, checking if its base in enclosing
249 contexts has changed. The alist is updated if necessary.
252 updated_grob_properties (Context *tg, SCM sym)
254 assert (scm_is_symbol (sym));
257 tg = tg->where_defined (sym, &props);
262 = (tg->get_parent_context ())
263 ? updated_grob_properties (tg->get_parent_context (), sym)
266 if (!scm_is_pair (props))
268 programming_error ("grob props not a pair?");
272 SCM based_on = scm_cdr (props);
273 if (based_on == daddy_props)
274 return scm_car (props);
277 SCM copy = daddy_props;
279 SCM p = scm_car (props);
280 while (p != based_on)
282 *tail = scm_cons (scm_car (p), daddy_props);
283 tail = SCM_CDRLOC (*tail);
287 scm_set_car_x (props, copy);
288 scm_set_cdr_x (props, daddy_props);