/*
- context-property.cc -- implement manipulation of immutable Grob
- property lists.
+ This file is part of LilyPond, the GNU music typesetter.
- source file of the GNU LilyPond music typesetter
+ Copyright (C) 2004--2011 Han-Wen Nienhuys <hanwen@xs4all.nl>
- (c) 2004--2007 Han-Wen Nienhuys <hanwen@xs4all.nl>
+ LilyPond is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ LilyPond is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with LilyPond. If not, see <http://www.gnu.org/licenses/>.
*/
#include "context.hh"
#include "spanner.hh"
#include "warn.hh"
-SCM
-lookup_nested_property (SCM alist,
- SCM grob_property_path)
-{
- if (scm_is_pair (grob_property_path))
- {
- SCM sym = scm_car (grob_property_path);
- SCM handle = scm_assq (sym, alist);
-
- if (handle == SCM_BOOL_F)
- return SCM_EOL;
- else
- return lookup_nested_property (scm_cdr (handle),
- scm_cdr (grob_property_path));
- }
- else
- return alist;
-}
-
/*
- copy ALIST leaving out SYMBOL. Copying stops at ALIST_END
+ like execute_general_pushpop_property(), but typecheck
+ grob_property_path and context_property.
*/
-SCM
-evict_from_alist (SCM symbol,
- SCM alist,
- SCM alist_end)
-{
- SCM new_alist = SCM_EOL;
- SCM *tail = &new_alist;
-
- while (alist != alist_end)
- {
- if (ly_is_equal (scm_caar (alist), symbol))
- {
- alist = scm_cdr (alist);
- break;
- }
-
- *tail = scm_cons (scm_car (alist), SCM_EOL);
- tail = SCM_CDRLOC (*tail);
- alist = scm_cdr (alist);
- }
-
- *tail = alist;
- return new_alist;
-}
-
void
general_pushpop_property (Context *context,
SCM context_property,
SCM grob_property_path,
- SCM new_value
- )
+ SCM new_value)
{
if (!scm_is_symbol (context_property)
|| !scm_is_symbol (scm_car (grob_property_path)))
assert (false);
}
- execute_general_pushpop_property (context, context_property,
- grob_property_path, new_value);
+ sloppy_general_pushpop_property (context, context_property,
+ grob_property_path, new_value);
}
/*
-
Grob descriptions (ie. alists with layout properties) are
represented as a (ALIST . BASED-ON) pair, where BASED-ON is the
alist defined in a parent context. BASED-ON should always be a tail
of ALIST.
- Push or pop (depending on value of VAL) a single entry entry from a
+ Push or pop (depending on value of VAL) a single entry from a
translator property list by name of PROP. GROB_PROPERTY_PATH
indicates nested alists, eg. '(beamed-stem-lengths details)
-
+
*/
void
-execute_general_pushpop_property (Context *context,
- SCM context_property,
- SCM grob_property_path,
- SCM new_value
- )
+execute_override_property (Context *context,
+ SCM context_property,
+ SCM grob_property_path,
+ SCM new_value)
{
SCM current_context_val = SCM_EOL;
- if (new_value != SCM_UNDEFINED)
- {
- Context *where = context->where_defined (context_property, ¤t_context_val);
- /*
- Don't mess with MIDI.
- */
- if (!where)
- return;
+ Context *where = context->where_defined (context_property,
+ ¤t_context_val);
- if (where != context)
- {
- SCM base = updated_grob_properties (context, context_property);
- current_context_val = scm_cons (base, base);
- context->set_property (context_property, current_context_val);
- }
+ /*
+ Don't mess with MIDI.
+ */
+ if (!where)
+ return;
- if (!scm_is_pair (current_context_val))
- {
- programming_error ("Grob definition should be cons");
- return;
- }
+ if (where != context)
+ {
+ SCM base = updated_grob_properties (context, context_property);
+ current_context_val = scm_cons (base, base);
+ context->set_property (context_property, current_context_val);
+ }
- SCM prev_alist = scm_car (current_context_val);
- SCM symbol = scm_car (grob_property_path);
- SCM target_alist
- = lookup_nested_property (prev_alist,
- scm_reverse (scm_cdr (grob_property_path)));
+ if (!scm_is_pair (current_context_val))
+ {
+ programming_error ("Grob definition should be cons");
+ return;
+ }
- target_alist = scm_acons (symbol, new_value, target_alist);
+ SCM target_alist = scm_car (current_context_val);
- bool ok = true;
- if (!scm_is_pair (scm_cdr (grob_property_path)))
- {
- if (!ly_is_procedure (new_value)
- && !is_simple_closure (new_value))
- ok = type_check_assignment (symbol, new_value,
- ly_symbol2scm ("backend-type?"));
-
- /*
- tack onto alist. We can use set_car, since
- updated_grob_properties() in child contexts will check
- for changes in the car.
- */
- if (ok)
- {
- scm_set_car_x (current_context_val, target_alist);
- }
- }
- else
- {
- execute_general_pushpop_property (context,
- context_property,
- scm_cdr (grob_property_path),
- target_alist
- );
- }
+ /*
+ If the car is a list, the property path comes from a nested override
+ using list syntax inside a \context block
+ */
+ if (scm_is_pair (scm_car (grob_property_path)))
+ grob_property_path = scm_car (grob_property_path);
+
+ SCM symbol = scm_car (grob_property_path);
+ if (scm_is_pair (scm_cdr (grob_property_path)))
+ {
+ new_value = nested_property_alist (ly_assoc_get (symbol, target_alist,
+ SCM_EOL),
+ scm_cdr (grob_property_path),
+ new_value);
}
- else if (context->where_defined (context_property, ¤t_context_val) == context)
+
+ /* it's tempting to replace the head of the list if it's the same
+ property. However, we have to keep this info around, in case we have to
+ \revert back to it.
+ */
+ target_alist = scm_acons (symbol, new_value, target_alist);
+
+ bool ok = true;
+ if (!ly_is_procedure (new_value)
+ && !is_simple_closure (new_value))
+ ok = type_check_assignment (symbol, new_value,
+ ly_symbol2scm ("backend-type?"));
+
+ /*
+ tack onto alist. We can use set_car, since
+ updated_grob_properties () in child contexts will check
+ for changes in the car.
+ */
+ if (ok)
{
- SCM current_value = scm_car (current_context_val);
+ scm_set_car_x (current_context_val, target_alist);
+ }
+}
+
+/*
+ do a pop (indicated by new_value==SCM_UNDEFINED) or push
+ */
+void
+sloppy_general_pushpop_property (Context *context,
+ SCM context_property,
+ SCM grob_property_path,
+ SCM new_value)
+{
+ if (new_value == SCM_UNDEFINED)
+ execute_revert_property (context, context_property,
+ grob_property_path);
+ else
+ execute_override_property (context, context_property,
+ grob_property_path,
+ new_value);
+}
+
+/*
+ Revert the property given by property_path.
+*/
+void
+execute_revert_property (Context *context,
+ SCM context_property,
+ SCM grob_property_path)
+{
+ SCM current_context_val = SCM_EOL;
+ if (context->where_defined (context_property, ¤t_context_val)
+ == context)
+ {
+ SCM current_alist = scm_car (current_context_val);
SCM daddy = scm_cdr (current_context_val);
if (!scm_is_pair (grob_property_path)
programming_error ("Grob property path should be list of symbols.");
return;
}
-
- SCM symbol = scm_car (grob_property_path);
- SCM new_alist = evict_from_alist (symbol, current_value, daddy);
- if (new_alist == daddy)
- context->unset_property (context_property);
+ SCM symbol = scm_car (grob_property_path);
+ if (scm_is_pair (scm_cdr (grob_property_path)))
+ {
+ SCM current_sub_alist = ly_assoc_get (symbol, current_alist, SCM_EOL);
+ SCM new_val
+ = nested_property_revert_alist (current_sub_alist,
+ scm_cdr (grob_property_path));
+
+ if (scm_is_pair (current_alist)
+ && scm_caar (current_alist) == symbol
+ && current_alist != daddy)
+ current_alist = scm_cdr (current_alist);
+
+ current_alist = scm_acons (symbol, new_val, current_alist);
+ scm_set_car_x (current_context_val, current_alist);
+ }
else
- context->set_property (context_property, scm_cons (new_alist, daddy));
+ {
+ SCM new_alist = evict_from_alist (symbol, current_alist, daddy);
+
+ if (new_alist == daddy)
+ context->unset_property (context_property);
+ else
+ context->set_property (context_property,
+ scm_cons (new_alist, daddy));
+ }
}
}
-
+/*
+ Convenience: a push/pop grob property using a single grob_property
+ as argument.
+*/
void
execute_pushpop_property (Context *context,
SCM context_property,
SCM grob_property,
- SCM new_value
- )
+ SCM new_value)
{
general_pushpop_property (context, context_property,
scm_list_1 (grob_property),
new_value);
}
-
+
/*
PRE_INIT_OPS is in the order specified, and hence must be reversed.
*/
SCM context_prop = scm_car (entry);
SCM val = scm_cadr (entry);
SCM grob_prop_path = scm_cddr (entry);
- execute_general_pushpop_property (tg, context_prop, grob_prop_path, val);
+ sloppy_general_pushpop_property (tg, context_prop, grob_prop_path, val);
}
else if (type == ly_symbol2scm ("pop"))
{
SCM context_prop = scm_car (entry);
SCM val = SCM_UNDEFINED;
SCM grob_prop_path = scm_cdr (entry);
- execute_general_pushpop_property (tg, context_prop, grob_prop_path, val);
+ sloppy_general_pushpop_property (tg, context_prop, grob_prop_path, val);
}
else if (type == ly_symbol2scm ("assign"))
tg->set_property (scm_car (entry), scm_cadr (entry));