2 This file is part of LilyPond, the GNU music typesetter.
4 Copyright (C) 2004--2010 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);
53 Grob descriptions (ie. alists with layout properties) are
54 represented as a (ALIST . BASED-ON) pair, where BASED-ON is the
55 alist defined in a parent context. BASED-ON should always be a tail
58 Push or pop (depending on value of VAL) a single entry from a
59 translator property list by name of PROP. GROB_PROPERTY_PATH
60 indicates nested alists, eg. '(beamed-stem-lengths details)
64 execute_override_property (Context *context,
66 SCM grob_property_path,
69 SCM current_context_val = SCM_EOL;
71 Context *where = context->where_defined (context_property,
72 ¤t_context_val);
82 SCM base = updated_grob_properties (context, context_property);
83 current_context_val = scm_cons (base, base);
84 context->set_property (context_property, current_context_val);
87 if (!scm_is_pair (current_context_val))
89 programming_error ("Grob definition should be cons");
93 SCM target_alist = scm_car (current_context_val);
96 If the car is a list, the property path comes from a nested override
97 using list syntax inside a \context block
99 if (scm_is_pair (scm_car (grob_property_path)))
100 grob_property_path = scm_car (grob_property_path);
102 SCM symbol = scm_car (grob_property_path);
103 if (scm_is_pair (scm_cdr (grob_property_path)))
105 new_value = nested_property_alist (ly_assoc_get (symbol, target_alist,
107 scm_cdr (grob_property_path),
111 /* it's tempting to replace the head of the list if it's the same
112 property. However, we have to keep this info around, in case we have to
115 target_alist = scm_acons (symbol, new_value, target_alist);
118 if (!ly_is_procedure (new_value)
119 && !is_simple_closure (new_value))
120 ok = type_check_assignment (symbol, new_value,
121 ly_symbol2scm ("backend-type?"));
124 tack onto alist. We can use set_car, since
125 updated_grob_properties () in child contexts will check
126 for changes in the car.
130 scm_set_car_x (current_context_val, target_alist);
135 do a pop (indicated by new_value==SCM_UNDEFINED) or push
138 sloppy_general_pushpop_property (Context *context,
139 SCM context_property,
140 SCM grob_property_path,
143 if (new_value == SCM_UNDEFINED)
144 execute_revert_property (context, context_property,
147 execute_override_property (context, context_property,
153 Revert the property given by property_path.
156 execute_revert_property (Context *context,
157 SCM context_property,
158 SCM grob_property_path)
160 SCM current_context_val = SCM_EOL;
161 if (context->where_defined (context_property, ¤t_context_val)
164 SCM current_alist = scm_car (current_context_val);
165 SCM daddy = scm_cdr (current_context_val);
167 if (!scm_is_pair (grob_property_path)
168 || !scm_is_symbol (scm_car (grob_property_path)))
170 programming_error ("Grob property path should be list of symbols.");
174 SCM symbol = scm_car (grob_property_path);
175 if (scm_is_pair (scm_cdr (grob_property_path)))
177 SCM current_sub_alist = ly_assoc_get (symbol, current_alist, SCM_EOL);
179 = nested_property_revert_alist (current_sub_alist,
180 scm_cdr (grob_property_path));
182 if (scm_is_pair (current_alist)
183 && scm_caar (current_alist) == symbol
184 && current_alist != daddy)
185 current_alist = scm_cdr (current_alist);
187 current_alist = scm_acons (symbol, new_val, current_alist);
188 scm_set_car_x (current_context_val, current_alist);
192 SCM new_alist = evict_from_alist (symbol, current_alist, daddy);
194 if (new_alist == daddy)
195 context->unset_property (context_property);
197 context->set_property (context_property,
198 scm_cons (new_alist, daddy));
203 Convenience: a push/pop grob property using a single grob_property
207 execute_pushpop_property (Context *context,
208 SCM context_property,
212 general_pushpop_property (context, context_property,
213 scm_list_1 (grob_property),
218 PRE_INIT_OPS is in the order specified, and hence must be reversed.
221 apply_property_operations (Context *tg, SCM pre_init_ops)
223 SCM correct_order = scm_reverse (pre_init_ops);
224 for (SCM s = correct_order; scm_is_pair (s); s = scm_cdr (s))
226 SCM entry = scm_car (s);
227 SCM type = scm_car (entry);
228 entry = scm_cdr (entry);
230 if (type == ly_symbol2scm ("push"))
232 SCM context_prop = scm_car (entry);
233 SCM val = scm_cadr (entry);
234 SCM grob_prop_path = scm_cddr (entry);
235 sloppy_general_pushpop_property (tg, context_prop, grob_prop_path, val);
237 else if (type == ly_symbol2scm ("pop"))
239 SCM context_prop = scm_car (entry);
240 SCM val = SCM_UNDEFINED;
241 SCM grob_prop_path = scm_cdr (entry);
242 sloppy_general_pushpop_property (tg, context_prop, grob_prop_path, val);
244 else if (type == ly_symbol2scm ("assign"))
245 tg->set_property (scm_car (entry), scm_cadr (entry));
250 Return the object alist for SYM, checking if its base in enclosing
251 contexts has changed. The alist is updated if necessary.
254 updated_grob_properties (Context *tg, SCM sym)
256 assert (scm_is_symbol (sym));
259 tg = tg->where_defined (sym, &props);
264 = (tg->get_parent_context ())
265 ? updated_grob_properties (tg->get_parent_context (), sym)
268 if (!scm_is_pair (props))
270 programming_error ("grob props not a pair?");
274 SCM based_on = scm_cdr (props);
275 if (based_on == daddy_props)
276 return scm_car (props);
279 SCM copy = daddy_props;
281 SCM p = scm_car (props);
282 while (p != based_on)
284 *tail = scm_cons (scm_car (p), daddy_props);
285 tail = SCM_CDRLOC (*tail);
289 scm_set_car_x (props, copy);
290 scm_set_cdr_x (props, daddy_props);