Mercurial > hg > xemacs-beta

comparison src/specifier.h @ 280:7df0dd720c89 r21-0b38

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Import from CVS: tag r21-0b38
author cvs
date Mon, 13 Aug 2007 10:32:22 +0200
parents 6330739388db
children 8626e4521993
comparison
equal deleted inserted replaced
279:c20b2fb5bb0a 280:7df0dd720c89
33 window system, such as default fonts, colors, scrollbar thickness 33 window system, such as default fonts, colors, scrollbar thickness
34 etc. 34 etc.
35 35
36 A magic specifier consists of two specifier objects. The first one 36 A magic specifier consists of two specifier objects. The first one
37 behaves like a normal specifier in all sences. The second one, a 37 behaves like a normal specifier in all sences. The second one, a
38 ghost specifier, is a fallback value for the first one. 38 ghost specifier, is a fallback value for the first one, and contains
39 values provided by window system, resources etc. which reflect
40 default settings for values being specified.
41
42 A magic specifier has an "ultimate" fallback value, as any usual
43 specifier does. This value, an inst-list, is stored in the fallback
44 slot of the ghost specifier object.
39 45
40 Ghost specifiers have the following properties: 46 Ghost specifiers have the following properties:
41 - Have back pointers to their parent specifiers. 47 - Have back pointers to their parent specifiers.
42 - Do not have instance data. Instead, they share parent's instance 48 - Do not have instance data. Instead, they share parent's instance
43 data. 49 data.
44 - Have the same methods structure pointer. 50 - Have the same methods structure pointer.
45 - Share parent's caching scheme. 51 - Share parent's caching scheme.
46 - Store fallback value instead of their parent. 52 - Store fallback value instead of their parents.
47 53
48 Ghost specifiers normally are not modifiable at the lisp level, and 54 Ghost specifiers normally are not modifiable at the lisp level, and
49 only used to supply fallback instance values. Although, under 55 only used to supply fallback instance values. They are accessible
50 certain rare conditions, all functions that modify specifiers 56 via (specifier-fallback), but are read-only. Although, under
51 operate on ghost objects. This behavior is controlled by the global 57 certain rare conditions, modification of ghost objects is allowed.
52 variable Vreveal_ghoste_specifiers. It is not exposed to lisp, and 58 This behavior is controlled by the global variable
53 is set during calls to lisp functions which initialize global, 59 Vunlock_ghost_specifiers. It is not exposed to lisp, and is set
54 device and frame defaults, such as 60 during calls to lisp functions which initialize global, device and
61 frame defaults, such as
55 init-{global,frame,device}-{faces,toolbars,etc}. 62 init-{global,frame,device}-{faces,toolbars,etc}.
56 63
57 Thus, values supplied by resources or other means of a window system 64 Thus, values supplied by resources or other means of a window system
58 stored in externally unmodifiable ghost objects. Regular lisp code 65 stored in externally unmodifiable ghost objects. Regular lisp code
59 may thus freely modify the normal part of a magic specifier, and 66 may thus freely modify the normal part of a magic specifier, and
61 specification to consider ghost-provided fallback values, or its own 68 specification to consider ghost-provided fallback values, or its own
62 fallback value. 69 fallback value.
63 70
64 Rules of conduct for magic specifiers 71 Rules of conduct for magic specifiers
65 ------------------------------------- 72 -------------------------------------
66 1. All functions exposed to lisp operate on a ghost specifier when 73 1. recompute_*() functions always operate on the whole specifier
67 Vreveal_ghoste_specifiers is non-nil. This includes both
68 modifying and non-modifying functions, such as
69 Fspecifier_instance, for symmetry and consistency.
70 2. These functions deal with the above condition internally, passing
71 mangled specifier pointer to internal functions. The internal
72 functions always work on a specifier passed, and do not regard
73 the value of Vreveal_ghoste_specifiers.
74 3. recompute_*() functions always operate on the whole specifier
75 when passed only a ghost object, by substituting it with their 74 when passed only a ghost object, by substituting it with their
76 parent bodily object. 75 parent bodily object.
77 4. All specifier methods, except for instantiate method, are passed 76 2. All specifier methods, except for instantiate method, are passed
78 the bodily object of the magic specifier. Instantiate method is 77 the bodily object of the magic specifier. Instantiate method is
79 passed the specifier being instantiated. 78 passed the specifier being instantiated.
80 5. Only bodily objects are passed to set_specifier_caching function, 79 3. Only bodily objects are passed to set_specifier_caching function,
81 and only these may be cached. 80 and only these may be cached.
82 6. All specifiers are added to Vall_specifiers list, both bodily and 81 4. All specifiers are added to Vall_specifiers list, both bodily and
83 ghost. The pair of objects is always removed from the list at the 82 ghost. The pair of objects is always removed from the list at the
84 same time. 83 same time.
85 */ 84 */
86 85
87 struct specifier_methods 86 struct specifier_methods
137 Qunbound when no matching constraints are imposed. The method is 136 Qunbound when no matching constraints are imposed. The method is
138 called via call_with_suspended_errors(), so allowed to eval 137 called via call_with_suspended_errors(), so allowed to eval
139 safely. 138 safely.
140 139
141 DEPTH is a lisp integer denoting current depth of instantiation 140 DEPTH is a lisp integer denoting current depth of instantiation
142 calls. #### WTF a method can do with this? 141 calls. This parameter should be passed as the initial depth value
142 to functions which also instantiate specifiers (of which I can
143 name specifier_instance) to avoid creating "external"
144 specification loops.
143 145
144 This method must presume that both INSTANTIATOR and MATCSPEC are 146 This method must presume that both INSTANTIATOR and MATCSPEC are
145 already validated by the corresponding validate_* methods, and 147 already validated by the corresponding validate_* methods, and
146 may abort if they are invalid. 148 may abort if they are invalid.
147 149
410 void set_specifier_fallback (Lisp_Object specifier, 412 void set_specifier_fallback (Lisp_Object specifier,
411 Lisp_Object fallback); 413 Lisp_Object fallback);
412 void recompute_all_cached_specifiers_in_window (struct window *w); 414 void recompute_all_cached_specifiers_in_window (struct window *w);
413 void recompute_all_cached_specifiers_in_frame (struct frame *f); 415 void recompute_all_cached_specifiers_in_frame (struct frame *f);
414 416
415 /* Counterparts of Fadd_spec_to_specifier and Fremove_specifier, 417 /* Counterparts of Fadd_spec_to_specifier and Fremove_specifier, which
416 which operate directly on ghost objects */ 418 operate directly on ghost objects given a magic specifier. */
417 void add_spec_to_ghost_specifier (Lisp_Object specifier, Lisp_Object instantiator, 419 void add_spec_to_ghost_specifier (Lisp_Object specifier, Lisp_Object instantiator,
418 Lisp_Object locale, Lisp_Object tag_set, 420 Lisp_Object locale, Lisp_Object tag_set,
419 Lisp_Object how_to_add); 421 Lisp_Object how_to_add);
420 void remove_ghost_specifier (Lisp_Object specifier, Lisp_Object locale, 422 void remove_ghost_specifier (Lisp_Object specifier, Lisp_Object locale,
421 Lisp_Object tag_set, Lisp_Object exact_p); 423 Lisp_Object tag_set, Lisp_Object exact_p);
422 424
423 int reveal_ghost_specifiers_protected (void); 425 int unlock_ghost_specifiers_protected (void);
424 426
425 void cleanup_specifiers (void); 427 void cleanup_specifiers (void);
426 void prune_specifiers (int (*obj_marked_p) (Lisp_Object)); 428 void prune_specifiers (int (*obj_marked_p) (Lisp_Object));
427 void setup_device_initial_specifier_tags (struct device *d); 429 void setup_device_initial_specifier_tags (struct device *d);
428 void kill_specifier_buffer_locals (Lisp_Object buffer); 430 void kill_specifier_buffer_locals (Lisp_Object buffer);