Mercurial > hg > xemacs-beta
annotate man/lispref/intro.texi @ 5142:f965e31a35f0
reduce lcrecord headers to 2 words, rename printing_unreadable_object
-------------------- ChangeLog entries follow: --------------------
man/ChangeLog addition:
2010-03-13 Ben Wing <ben@xemacs.org>
* internals/internals.texi (Working with Lisp Objects):
* internals/internals.texi (Writing Macros):
* internals/internals.texi (lrecords):
More rewriting to correspond with changes from
*LRECORD* to *LISP_OBJECT*.
modules/ChangeLog addition:
2010-03-13 Ben Wing <ben@xemacs.org>
* postgresql/postgresql.c (print_pgconn):
* postgresql/postgresql.c (print_pgresult):
printing_unreadable_object -> printing_unreadable_object_fmt.
2010-03-13 Ben Wing <ben@xemacs.org>
* ldap/eldap.c (print_ldap):
printing_unreadable_object -> printing_unreadable_object_fmt.
src/ChangeLog addition:
2010-03-13 Ben Wing <ben@xemacs.org>
* alloc.c (alloc_sized_lrecord_1):
* alloc.c (alloc_sized_lrecord_array):
* alloc.c (old_alloc_sized_lcrecord):
* alloc.c (disksave_object_finalization_1):
* alloc.c (mark_lcrecord_list):
* alloc.c (alloc_managed_lcrecord):
* alloc.c (free_managed_lcrecord):
* alloc.c (tick_lcrecord_stats):
* alloc.c (sweep_lcrecords_1):
* buffer.c (print_buffer):
* buffer.c (DEFVAR_BUFFER_LOCAL_1):
* casetab.c:
* casetab.c (print_case_table):
* console.c (print_console):
* console.c (DEFVAR_CONSOLE_LOCAL_1):
* data.c (print_weak_list):
* data.c (print_weak_box):
* data.c (print_ephemeron):
* data.c (ephemeron_equal):
* database.c (print_database):
* database.c (finalize_database):
* device-msw.c (sync_printer_with_devmode):
* device-msw.c (print_devmode):
* device-msw.c (finalize_devmode):
* device.c:
* device.c (print_device):
* elhash.c:
* elhash.c (print_hash_table):
* eval.c (print_subr):
* eval.c (print_multiple_value):
* event-stream.c (event_stream_resignal_wakeup):
* events.c (clear_event_resource):
* events.c (zero_event):
* events.c (print_event):
* extents.c:
* extents.c (print_extent):
* file-coding.c (print_coding_system):
* font-mgr.c:
* font-mgr.c (Ffc_init):
* frame.c:
* frame.c (print_frame):
* gc.c:
* gc.c (GC_CHECK_NOT_FREE):
* glyphs.c:
* glyphs.c (print_image_instance):
* glyphs.c (print_glyph):
* gui.c (print_gui_item):
* gui.c (copy_gui_item):
* keymap.c (print_keymap):
* keymap.c (MARKED_SLOT):
* lisp.h:
* lisp.h (struct Lisp_String):
* lisp.h (DEFUN):
* lisp.h (DEFUN_NORETURN):
* lrecord.h:
* lrecord.h (NORMAL_LISP_OBJECT_UID):
* lrecord.h (struct lrecord_header):
* lrecord.h (set_lheader_implementation):
* lrecord.h (struct old_lcrecord_header):
* lrecord.h (struct free_lcrecord_header):
* marker.c (print_marker):
* mule-charset.c:
* mule-charset.c (print_charset):
* objects.c (print_color_instance):
* objects.c (print_font_instance):
* objects.c (finalize_font_instance):
* print.c (print_cons):
* print.c (printing_unreadable_object_fmt):
* print.c (printing_unreadable_lisp_object):
* print.c (external_object_printer):
* print.c (internal_object_printer):
* print.c (debug_p4):
* print.c (ext_print_begin):
* process.c (print_process):
* rangetab.c (print_range_table):
* rangetab.c (range_table_equal):
* scrollbar.c (free_scrollbar_instance):
* specifier.c (print_specifier):
* specifier.c (finalize_specifier):
* symbols.c (guts_of_unbound_marker):
* symeval.h:
* symeval.h (DEFVAR_SYMVAL_FWD):
* tooltalk.c:
* tooltalk.c (print_tooltalk_message):
* tooltalk.c (print_tooltalk_pattern):
* ui-gtk.c (ffi_object_printer):
* ui-gtk.c (emacs_gtk_object_printer):
* ui-gtk.c (emacs_gtk_boxed_printer):
* window.c (print_window):
* window.c (free_window_mirror):
* window.c (debug_print_window):
* xemacs.def.in.in:
(1) printing_unreadable_object -> printing_unreadable_object_fmt.
(2) printing_unreadable_lcrecord -> printing_unreadable_lisp_object
and fix up so it no longer requires an lcrecord.
These previous changes eliminate most of the remaining places where
the terms `lcrecord' and `lrecord' occurred outside of specialized
code.
(3) Fairly major change: Reduce the number of words in an lcrecord
from 3 to 2. The third word consisted of a uid that duplicated the
lrecord uid, and a single free bit, which was moved into the lrecord
structure. This reduces the size of the `uid' slot from 21 bits to
20 bits. Arguably this isn't enough -- we could easily have more than
1,000,000 or so objects created in a session. The answer is
(a) It doesn't really matter if we overflow the uid field because
it's only used for debugging, to identify an object uniquely
(or pretty much so).
(b) If we cared about it overflowing and wanted to reduce this,
we could make it so that cons, string, float and certain other
frob-block types that never print out the uid simply don't
store a uid in them and don't increment the lrecord_uid_counter.
(4) In conjunction with (3), create new macro NORMAL_LISP_OBJECT_UID()
and use it to abstract out the differences between NEWGC and old-GC
in accessing the `uid' value from a "normal Lisp Object pointer".
(5) In events.c, use zero_nonsized_lisp_object() in place of custom-
written equivalent. In font-mgr.c use external_object_printer()
in place of custom-written equivalents.
author | Ben Wing <ben@xemacs.org> |
---|---|
date | Sat, 13 Mar 2010 05:38:08 -0600 |
parents | 755ae5b97edb |
children | 62b9ef1ed4ac |
rev | line source |
---|---|
428 | 1 @c -*-texinfo-*- |
2 @c This is part of the XEmacs Lisp Reference Manual. | |
444 | 3 @c Copyright (C) 1990, 1991, 1992, 1993, 1994 Free Software Foundation, Inc. |
428 | 4 @c See the file lispref.texi for copying conditions. |
5 @setfilename ../../info/intro.info | |
6 | |
7 @node Copying, Introduction, Top, Top | |
8 @unnumbered GNU GENERAL PUBLIC LICENSE | |
9 @center Version 2, June 1991 | |
10 | |
11 @display | |
12 Copyright @copyright{} 1989, 1991 Free Software Foundation, Inc. | |
13 675 Mass Ave, Cambridge, MA 02139, USA | |
14 | |
15 Everyone is permitted to copy and distribute verbatim copies | |
16 of this license document, but changing it is not allowed. | |
17 @end display | |
18 | |
19 @unnumberedsec Preamble | |
20 | |
21 The licenses for most software are designed to take away your | |
22 freedom to share and change it. By contrast, the GNU General Public | |
23 License is intended to guarantee your freedom to share and change free | |
24 software---to make sure the software is free for all its users. This | |
25 General Public License applies to most of the Free Software | |
26 Foundation's software and to any other program whose authors commit to | |
27 using it. (Some other Free Software Foundation software is covered by | |
28 the GNU Library General Public License instead.) You can apply it to | |
29 your programs, too. | |
30 | |
31 When we speak of free software, we are referring to freedom, not | |
32 price. Our General Public Licenses are designed to make sure that you | |
33 have the freedom to distribute copies of free software (and charge for | |
34 this service if you wish), that you receive source code or can get it | |
35 if you want it, that you can change the software or use pieces of it | |
36 in new free programs; and that you know you can do these things. | |
37 | |
38 To protect your rights, we need to make restrictions that forbid | |
39 anyone to deny you these rights or to ask you to surrender the rights. | |
40 These restrictions translate to certain responsibilities for you if you | |
41 distribute copies of the software, or if you modify it. | |
42 | |
43 For example, if you distribute copies of such a program, whether | |
44 gratis or for a fee, you must give the recipients all the rights that | |
45 you have. You must make sure that they, too, receive or can get the | |
46 source code. And you must show them these terms so they know their | |
47 rights. | |
48 | |
49 We protect your rights with two steps: (1) copyright the software, and | |
50 (2) offer you this license which gives you legal permission to copy, | |
51 distribute and/or modify the software. | |
52 | |
53 Also, for each author's protection and ours, we want to make certain | |
54 that everyone understands that there is no warranty for this free | |
55 software. If the software is modified by someone else and passed on, we | |
56 want its recipients to know that what they have is not the original, so | |
57 that any problems introduced by others will not reflect on the original | |
58 authors' reputations. | |
59 | |
60 Finally, any free program is threatened constantly by software | |
61 patents. We wish to avoid the danger that redistributors of a free | |
62 program will individually obtain patent licenses, in effect making the | |
63 program proprietary. To prevent this, we have made it clear that any | |
64 patent must be licensed for everyone's free use or not licensed at all. | |
65 | |
66 The precise terms and conditions for copying, distribution and | |
67 modification follow. | |
68 | |
69 @iftex | |
70 @unnumberedsec TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION | |
71 @end iftex | |
72 @ifinfo | |
73 @center TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION | |
74 @end ifinfo | |
75 | |
76 @enumerate 0 | |
77 @item | |
78 This License applies to any program or other work which contains | |
79 a notice placed by the copyright holder saying it may be distributed | |
80 under the terms of this General Public License. The ``Program'', below, | |
81 refers to any such program or work, and a ``work based on the Program'' | |
82 means either the Program or any derivative work under copyright law: | |
83 that is to say, a work containing the Program or a portion of it, | |
84 either verbatim or with modifications and/or translated into another | |
85 language. (Hereinafter, translation is included without limitation in | |
86 the term ``modification''.) Each licensee is addressed as ``you''. | |
87 | |
88 Activities other than copying, distribution and modification are not | |
89 covered by this License; they are outside its scope. The act of | |
90 running the Program is not restricted, and the output from the Program | |
91 is covered only if its contents constitute a work based on the | |
92 Program (independent of having been made by running the Program). | |
93 Whether that is true depends on what the Program does. | |
94 | |
95 @item | |
96 You may copy and distribute verbatim copies of the Program's | |
97 source code as you receive it, in any medium, provided that you | |
98 conspicuously and appropriately publish on each copy an appropriate | |
99 copyright notice and disclaimer of warranty; keep intact all the | |
100 notices that refer to this License and to the absence of any warranty; | |
101 and give any other recipients of the Program a copy of this License | |
102 along with the Program. | |
103 | |
104 You may charge a fee for the physical act of transferring a copy, and | |
105 you may at your option offer warranty protection in exchange for a fee. | |
106 | |
107 @item | |
108 You may modify your copy or copies of the Program or any portion | |
109 of it, thus forming a work based on the Program, and copy and | |
110 distribute such modifications or work under the terms of Section 1 | |
111 above, provided that you also meet all of these conditions: | |
112 | |
113 @enumerate a | |
114 @item | |
115 You must cause the modified files to carry prominent notices | |
116 stating that you changed the files and the date of any change. | |
117 | |
118 @item | |
119 You must cause any work that you distribute or publish, that in | |
120 whole or in part contains or is derived from the Program or any | |
121 part thereof, to be licensed as a whole at no charge to all third | |
122 parties under the terms of this License. | |
123 | |
124 @item | |
125 If the modified program normally reads commands interactively | |
126 when run, you must cause it, when started running for such | |
127 interactive use in the most ordinary way, to print or display an | |
128 announcement including an appropriate copyright notice and a | |
129 notice that there is no warranty (or else, saying that you provide | |
130 a warranty) and that users may redistribute the program under | |
131 these conditions, and telling the user how to view a copy of this | |
132 License. (Exception: if the Program itself is interactive but | |
133 does not normally print such an announcement, your work based on | |
134 the Program is not required to print an announcement.) | |
135 @end enumerate | |
136 | |
137 These requirements apply to the modified work as a whole. If | |
138 identifiable sections of that work are not derived from the Program, | |
139 and can be reasonably considered independent and separate works in | |
140 themselves, then this License, and its terms, do not apply to those | |
141 sections when you distribute them as separate works. But when you | |
142 distribute the same sections as part of a whole which is a work based | |
143 on the Program, the distribution of the whole must be on the terms of | |
144 this License, whose permissions for other licensees extend to the | |
145 entire whole, and thus to each and every part regardless of who wrote it. | |
146 | |
147 Thus, it is not the intent of this section to claim rights or contest | |
148 your rights to work written entirely by you; rather, the intent is to | |
149 exercise the right to control the distribution of derivative or | |
150 collective works based on the Program. | |
151 | |
152 In addition, mere aggregation of another work not based on the Program | |
153 with the Program (or with a work based on the Program) on a volume of | |
154 a storage or distribution medium does not bring the other work under | |
155 the scope of this License. | |
156 | |
157 @item | |
158 You may copy and distribute the Program (or a work based on it, | |
159 under Section 2) in object code or executable form under the terms of | |
160 Sections 1 and 2 above provided that you also do one of the following: | |
161 | |
162 @enumerate a | |
163 @item | |
164 Accompany it with the complete corresponding machine-readable | |
165 source code, which must be distributed under the terms of Sections | |
166 1 and 2 above on a medium customarily used for software interchange; or, | |
167 | |
168 @item | |
169 Accompany it with a written offer, valid for at least three | |
170 years, to give any third party, for a charge no more than your | |
171 cost of physically performing source distribution, a complete | |
172 machine-readable copy of the corresponding source code, to be | |
173 distributed under the terms of Sections 1 and 2 above on a medium | |
174 customarily used for software interchange; or, | |
175 | |
176 @item | |
177 Accompany it with the information you received as to the offer | |
178 to distribute corresponding source code. (This alternative is | |
179 allowed only for noncommercial distribution and only if you | |
180 received the program in object code or executable form with such | |
181 an offer, in accord with Subsection b above.) | |
182 @end enumerate | |
183 | |
184 The source code for a work means the preferred form of the work for | |
185 making modifications to it. For an executable work, complete source | |
186 code means all the source code for all modules it contains, plus any | |
187 associated interface definition files, plus the scripts used to | |
188 control compilation and installation of the executable. However, as a | |
189 special exception, the source code distributed need not include | |
190 anything that is normally distributed (in either source or binary | |
191 form) with the major components (compiler, kernel, and so on) of the | |
192 operating system on which the executable runs, unless that component | |
193 itself accompanies the executable. | |
194 | |
195 If distribution of executable or object code is made by offering | |
196 access to copy from a designated place, then offering equivalent | |
197 access to copy the source code from the same place counts as | |
198 distribution of the source code, even though third parties are not | |
199 compelled to copy the source along with the object code. | |
200 | |
201 @item | |
202 You may not copy, modify, sublicense, or distribute the Program | |
203 except as expressly provided under this License. Any attempt | |
204 otherwise to copy, modify, sublicense or distribute the Program is | |
205 void, and will automatically terminate your rights under this License. | |
206 However, parties who have received copies, or rights, from you under | |
207 this License will not have their licenses terminated so long as such | |
208 parties remain in full compliance. | |
209 | |
210 @item | |
211 You are not required to accept this License, since you have not | |
212 signed it. However, nothing else grants you permission to modify or | |
213 distribute the Program or its derivative works. These actions are | |
214 prohibited by law if you do not accept this License. Therefore, by | |
215 modifying or distributing the Program (or any work based on the | |
216 Program), you indicate your acceptance of this License to do so, and | |
217 all its terms and conditions for copying, distributing or modifying | |
218 the Program or works based on it. | |
219 | |
220 @item | |
221 Each time you redistribute the Program (or any work based on the | |
222 Program), the recipient automatically receives a license from the | |
223 original licensor to copy, distribute or modify the Program subject to | |
224 these terms and conditions. You may not impose any further | |
225 restrictions on the recipients' exercise of the rights granted herein. | |
226 You are not responsible for enforcing compliance by third parties to | |
227 this License. | |
228 | |
229 @item | |
230 If, as a consequence of a court judgment or allegation of patent | |
231 infringement or for any other reason (not limited to patent issues), | |
232 conditions are imposed on you (whether by court order, agreement or | |
233 otherwise) that contradict the conditions of this License, they do not | |
234 excuse you from the conditions of this License. If you cannot | |
235 distribute so as to satisfy simultaneously your obligations under this | |
236 License and any other pertinent obligations, then as a consequence you | |
237 may not distribute the Program at all. For example, if a patent | |
238 license would not permit royalty-free redistribution of the Program by | |
239 all those who receive copies directly or indirectly through you, then | |
240 the only way you could satisfy both it and this License would be to | |
241 refrain entirely from distribution of the Program. | |
242 | |
243 If any portion of this section is held invalid or unenforceable under | |
244 any particular circumstance, the balance of the section is intended to | |
245 apply and the section as a whole is intended to apply in other | |
246 circumstances. | |
247 | |
248 It is not the purpose of this section to induce you to infringe any | |
249 patents or other property right claims or to contest validity of any | |
250 such claims; this section has the sole purpose of protecting the | |
251 integrity of the free software distribution system, which is | |
252 implemented by public license practices. Many people have made | |
253 generous contributions to the wide range of software distributed | |
254 through that system in reliance on consistent application of that | |
255 system; it is up to the author/donor to decide if he or she is willing | |
256 to distribute software through any other system and a licensee cannot | |
257 impose that choice. | |
258 | |
259 This section is intended to make thoroughly clear what is believed to | |
260 be a consequence of the rest of this License. | |
261 | |
262 @item | |
263 If the distribution and/or use of the Program is restricted in | |
264 certain countries either by patents or by copyrighted interfaces, the | |
265 original copyright holder who places the Program under this License | |
266 may add an explicit geographical distribution limitation excluding | |
267 those countries, so that distribution is permitted only in or among | |
268 countries not thus excluded. In such case, this License incorporates | |
269 the limitation as if written in the body of this License. | |
270 | |
271 @item | |
272 The Free Software Foundation may publish revised and/or new versions | |
273 of the General Public License from time to time. Such new versions will | |
274 be similar in spirit to the present version, but may differ in detail to | |
275 address new problems or concerns. | |
276 | |
277 Each version is given a distinguishing version number. If the Program | |
278 specifies a version number of this License which applies to it and ``any | |
279 later version'', you have the option of following the terms and conditions | |
280 either of that version or of any later version published by the Free | |
281 Software Foundation. If the Program does not specify a version number of | |
282 this License, you may choose any version ever published by the Free Software | |
283 Foundation. | |
284 | |
285 @item | |
286 If you wish to incorporate parts of the Program into other free | |
287 programs whose distribution conditions are different, write to the author | |
288 to ask for permission. For software which is copyrighted by the Free | |
289 Software Foundation, write to the Free Software Foundation; we sometimes | |
290 make exceptions for this. Our decision will be guided by the two goals | |
291 of preserving the free status of all derivatives of our free software and | |
292 of promoting the sharing and reuse of software generally. | |
293 | |
294 @iftex | |
295 @heading NO WARRANTY | |
296 @end iftex | |
297 @ifinfo | |
298 @center NO WARRANTY | |
299 @end ifinfo | |
300 | |
301 @item | |
302 BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY | |
303 FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW@. EXCEPT WHEN | |
304 OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES | |
305 PROVIDE THE PROGRAM ``AS IS'' WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED | |
306 OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF | |
307 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE@. THE ENTIRE RISK AS | |
308 TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU@. SHOULD THE | |
309 PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, | |
310 REPAIR OR CORRECTION. | |
311 | |
312 @item | |
313 IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING | |
314 WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR | |
315 REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, | |
316 INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING | |
317 OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED | |
318 TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY | |
319 YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER | |
320 PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE | |
321 POSSIBILITY OF SUCH DAMAGES. | |
322 @end enumerate | |
323 | |
324 @iftex | |
325 @heading END OF TERMS AND CONDITIONS | |
326 @end iftex | |
327 @ifinfo | |
328 @center END OF TERMS AND CONDITIONS | |
329 @end ifinfo | |
330 | |
331 @page | |
332 @unnumberedsec How to Apply These Terms to Your New Programs | |
333 | |
334 If you develop a new program, and you want it to be of the greatest | |
335 possible use to the public, the best way to achieve this is to make it | |
336 free software which everyone can redistribute and change under these terms. | |
337 | |
338 To do so, attach the following notices to the program. It is safest | |
339 to attach them to the start of each source file to most effectively | |
340 convey the exclusion of warranty; and each file should have at least | |
341 the ``copyright'' line and a pointer to where the full notice is found. | |
342 | |
343 @smallexample | |
344 @var{one line to give the program's name and an idea of what it does.} | |
345 Copyright (C) 19@var{yy} @var{name of author} | |
346 | |
347 This program is free software; you can redistribute it and/or | |
348 modify it under the terms of the GNU General Public License | |
349 as published by the Free Software Foundation; either version 2 | |
350 of the License, or (at your option) any later version. | |
351 | |
352 This program is distributed in the hope that it will be useful, | |
353 but WITHOUT ANY WARRANTY; without even the implied warranty of | |
354 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE@. See the | |
355 GNU General Public License for more details. | |
356 | |
357 You should have received a copy of the GNU General Public License | |
358 along with this program; if not, write to the Free Software | |
359 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | |
360 @end smallexample | |
361 | |
362 Also add information on how to contact you by electronic and paper mail. | |
363 | |
364 If the program is interactive, make it output a short notice like this | |
365 when it starts in an interactive mode: | |
366 | |
367 @smallexample | |
368 Gnomovision version 69, Copyright (C) 19@var{yy} @var{name of author} | |
369 Gnomovision comes with ABSOLUTELY NO WARRANTY; for details | |
370 type `show w'. This is free software, and you are welcome | |
444 | 371 to redistribute it under certain conditions; type `show c' |
428 | 372 for details. |
373 @end smallexample | |
374 | |
375 The hypothetical commands @samp{show w} and @samp{show c} should show | |
376 the appropriate parts of the General Public License. Of course, the | |
377 commands you use may be called something other than @samp{show w} and | |
378 @samp{show c}; they could even be mouse-clicks or menu items---whatever | |
379 suits your program. | |
380 | |
381 You should also get your employer (if you work as a programmer) or your | |
382 school, if any, to sign a ``copyright disclaimer'' for the program, if | |
383 necessary. Here is a sample; alter the names: | |
384 | |
385 @smallexample | |
386 @group | |
387 Yoyodyne, Inc., hereby disclaims all copyright | |
388 interest in the program `Gnomovision' | |
444 | 389 (which makes passes at compilers) written |
428 | 390 by James Hacker. |
391 | |
392 @var{signature of Ty Coon}, 1 April 1989 | |
393 Ty Coon, President of Vice | |
394 @end group | |
395 @end smallexample | |
396 | |
397 This General Public License does not permit incorporating your program into | |
398 proprietary programs. If your program is a subroutine library, you may | |
399 consider it more useful to permit linking proprietary applications with the | |
400 library. If this is what you want to do, use the GNU Library General | |
401 Public License instead of this License. | |
402 | |
693 | 403 @node Introduction, Packaging, Copying, Top |
428 | 404 @chapter Introduction |
405 | |
406 Most of the XEmacs text editor is written in the programming | |
407 language called XEmacs Lisp. You can write new code in XEmacs Lisp and | |
408 install it as an extension to the editor. However, XEmacs Lisp is more | |
409 than a mere ``extension language''; it is a full computer programming | |
410 language in its own right. You can use it as you would any other | |
411 programming language. | |
412 | |
413 Because XEmacs Lisp is designed for use in an editor, it has special | |
414 features for scanning and parsing text as well as features for handling | |
415 files, buffers, displays, subprocesses, and so on. XEmacs Lisp is | |
416 closely integrated with the editing facilities; thus, editing commands | |
417 are functions that can also conveniently be called from Lisp programs, | |
418 and parameters for customization are ordinary Lisp variables. | |
419 | |
420 This manual describes XEmacs Lisp, presuming considerable familiarity | |
421 with the use of XEmacs for editing. (See @cite{The XEmacs Reference | |
422 Manual}, for this basic information.) Generally speaking, the earlier | |
423 chapters describe features of XEmacs Lisp that have counterparts in many | |
424 programming languages, and later chapters describe features that are | |
425 peculiar to XEmacs Lisp or relate specifically to editing. | |
426 | |
427 This is edition 3.3. | |
428 | |
429 @menu | |
430 * Caveats:: Flaws and a request for help. | |
431 * Lisp History:: XEmacs Lisp is descended from Maclisp. | |
432 * Conventions:: How the manual is formatted. | |
433 * Acknowledgements:: The authors, editors, and sponsors of this manual. | |
434 @end menu | |
435 | |
436 @node Caveats | |
437 @section Caveats | |
438 | |
439 This manual has gone through numerous drafts. It is nearly complete | |
440 but not flawless. There are a few topics that are not covered, either | |
441 because we consider them secondary (such as most of the individual | |
442 modes) or because they are yet to be written. Because we are not able | |
443 to deal with them completely, we have left out several parts | |
444 | 444 intentionally. |
428 | 445 |
446 The manual should be fully correct in what it does cover, and it is | |
447 therefore open to criticism on anything it says---from specific examples | |
448 and descriptive text, to the ordering of chapters and sections. If | |
449 something is confusing, or you find that you have to look at the sources | |
450 or experiment to learn something not covered in the manual, then perhaps | |
451 the manual should be fixed. Please let us know. | |
452 | |
453 @iftex | |
454 As you use the manual, we ask that you mark pages with corrections so | |
455 you can later look them up and send them in. If you think of a simple, | |
456 real-life example for a function or group of functions, please make an | |
457 effort to write it up and send it in. Please reference any comments to | |
458 the chapter name, section name, and function name, as appropriate, since | |
459 page numbers and chapter and section numbers will change and we may have | |
460 trouble finding the text you are talking about. Also state the number | |
461 of the edition you are criticizing. | |
462 @end iftex | |
463 @ifinfo | |
464 | |
465 As you use this manual, we ask that you send corrections as soon as you | |
466 find them. If you think of a simple, real life example for a function | |
467 or group of functions, please make an effort to write it up and send it | |
468 in. Please reference any comments to the node name and function or | |
469 variable name, as appropriate. Also state the number of the edition | |
470 which you are criticizing. | |
471 @end ifinfo | |
472 | |
473 This manual was originally written for FSF Emacs 19 and was updated by | |
474 Ben Wing (ben@@xemacs.org) for Lucid Emacs 19.10 and later for XEmacs | |
475 19.12, 19.13, 19.14, and 20.0. It was further updated by the XEmacs | |
476 Development Team for 19.15 and 20.1. Please send comments and | |
477 corrections relating to XEmacs-specific portions of this manual to | |
478 @example | |
479 xemacs@@xemacs.org | |
480 @end example | |
481 | |
482 or post to the newsgroup | |
483 @example | |
484 comp.emacs.xemacs | |
485 @end example | |
486 | |
487 @noindent | |
488 @display | |
489 --Ben Wing | |
490 @end display | |
491 | |
492 @node Lisp History | |
493 @section Lisp History | |
494 @cindex Lisp history | |
495 | |
496 Lisp (LISt Processing language) was first developed in the late 1950's | |
497 at the Massachusetts Institute of Technology for research in artificial | |
498 intelligence. The great power of the Lisp language makes it superior | |
499 for other purposes as well, such as writing editing commands. | |
500 | |
501 @cindex Maclisp | |
502 @cindex Common Lisp | |
503 Dozens of Lisp implementations have been built over the years, each | |
504 with its own idiosyncrasies. Many of them were inspired by Maclisp, | |
505 which was written in the 1960's at MIT's Project MAC. Eventually the | |
506 implementors of the descendants of Maclisp came together and developed a | |
507 standard for Lisp systems, called Common Lisp. | |
508 | |
509 XEmacs Lisp is largely inspired by Maclisp, and a little by Common | |
510 Lisp. If you know Common Lisp, you will notice many similarities. | |
511 However, many of the features of Common Lisp have been omitted or | |
512 simplified in order to reduce the memory requirements of XEmacs. | |
513 Sometimes the simplifications are so drastic that a Common Lisp user | |
514 might be very confused. We will occasionally point out how XEmacs | |
515 Lisp differs from Common Lisp. If you don't know Common Lisp, don't | |
516 worry about it; this manual is self-contained. | |
517 | |
518 @node Conventions | |
519 @section Conventions | |
520 | |
521 This section explains the notational conventions that are used in this | |
522 manual. You may want to skip this section and refer back to it later. | |
523 | |
524 @menu | |
525 * Some Terms:: Explanation of terms we use in this manual. | |
526 * nil and t:: How the symbols @code{nil} and @code{t} are used. | |
527 * Evaluation Notation:: The format we use for examples of evaluation. | |
528 * Printing Notation:: The format we use for examples that print output. | |
529 * Error Messages:: The format we use for examples of errors. | |
530 * Buffer Text Notation:: The format we use for buffer contents in examples. | |
531 * Format of Descriptions:: Notation for describing functions, variables, etc. | |
532 @end menu | |
533 | |
534 @node Some Terms | |
535 @subsection Some Terms | |
536 | |
537 Throughout this manual, the phrases ``the Lisp reader'' and ``the Lisp | |
538 printer'' are used to refer to those routines in Lisp that convert | |
539 textual representations of Lisp objects into actual Lisp objects, and vice | |
540 versa. @xref{Printed Representation}, for more details. You, the | |
541 person reading this manual, are thought of as ``the programmer'' and are | |
542 addressed as ``you''. ``The user'' is the person who uses Lisp programs, | |
543 including those you write. | |
544 | |
545 @cindex fonts | |
546 Examples of Lisp code appear in this font or form: @code{(list 1 2 | |
547 3)}. Names that represent arguments or metasyntactic variables appear | |
548 in this font or form: @var{first-number}. | |
549 | |
550 @node nil and t | |
551 @subsection @code{nil} and @code{t} | |
552 @cindex @code{nil}, uses of | |
553 @cindex truth value | |
554 @cindex boolean | |
555 @cindex false | |
556 | |
557 In Lisp, the symbol @code{nil} has three separate meanings: it | |
558 is a symbol with the name @samp{nil}; it is the logical truth value | |
559 @var{false}; and it is the empty list---the list of zero elements. | |
560 When used as a variable, @code{nil} always has the value @code{nil}. | |
561 | |
562 As far as the Lisp reader is concerned, @samp{()} and @samp{nil} are | |
563 identical: they stand for the same object, the symbol @code{nil}. The | |
564 different ways of writing the symbol are intended entirely for human | |
565 readers. After the Lisp reader has read either @samp{()} or @samp{nil}, | |
566 there is no way to determine which representation was actually written | |
567 by the programmer. | |
568 | |
569 In this manual, we use @code{()} when we wish to emphasize that it | |
570 means the empty list, and we use @code{nil} when we wish to emphasize | |
571 that it means the truth value @var{false}. That is a good convention to use | |
572 in Lisp programs also. | |
573 | |
574 @example | |
575 (cons 'foo ()) ; @r{Emphasize the empty list} | |
576 (not nil) ; @r{Emphasize the truth value @var{false}} | |
577 @end example | |
578 | |
579 @cindex @code{t} and truth | |
580 @cindex true | |
581 In contexts where a truth value is expected, any non-@code{nil} value | |
582 is considered to be @var{true}. However, @code{t} is the preferred way | |
583 to represent the truth value @var{true}. When you need to choose a | |
584 value which represents @var{true}, and there is no other basis for | |
585 choosing, use @code{t}. The symbol @code{t} always has value @code{t}. | |
586 | |
587 In XEmacs Lisp, @code{nil} and @code{t} are special symbols that always | |
588 evaluate to themselves. This is so that you do not need to quote them | |
589 to use them as constants in a program. An attempt to change their | |
590 values results in a @code{setting-constant} error. @xref{Accessing | |
591 Variables}. | |
592 | |
593 @node Evaluation Notation | |
594 @subsection Evaluation Notation | |
595 @cindex evaluation notation | |
596 @cindex documentation notation | |
597 | |
598 A Lisp expression that you can evaluate is called a @dfn{form}. | |
599 Evaluating a form always produces a result, which is a Lisp object. In | |
600 the examples in this manual, this is indicated with @samp{@result{}}: | |
601 | |
602 @example | |
603 (car '(1 2)) | |
604 @result{} 1 | |
605 @end example | |
606 | |
607 @noindent | |
608 You can read this as ``@code{(car '(1 2))} evaluates to 1''. | |
609 | |
610 When a form is a macro call, it expands into a new form for Lisp to | |
611 evaluate. We show the result of the expansion with | |
612 @samp{@expansion{}}. We may or may not show the actual result of the | |
613 evaluation of the expanded form. | |
614 | |
615 @example | |
616 (news-cadr '(a b c)) | |
617 @expansion{} (car (cdr '(a b c))) | |
618 @result{} b | |
619 @end example | |
620 | |
621 Sometimes to help describe one form we show another form that | |
622 produces identical results. The exact equivalence of two forms is | |
623 indicated with @samp{@equiv{}}. | |
624 | |
625 @example | |
626 (cons 'a nil) @equiv{} (list 'a) | |
627 @end example | |
628 | |
629 @node Printing Notation | |
630 @subsection Printing Notation | |
631 @cindex printing notation | |
632 | |
633 Many of the examples in this manual print text when they are | |
634 evaluated. If you execute example code in a Lisp Interaction buffer | |
635 (such as the buffer @samp{*scratch*}), the printed text is inserted into | |
636 the buffer. If you execute the example by other means (such as by | |
637 evaluating the function @code{eval-region}), the printed text is | |
638 displayed in the echo area. You should be aware that text displayed in | |
639 the echo area is truncated to a single line. | |
640 | |
641 Examples in this manual indicate printed text with @samp{@print{}}, | |
642 irrespective of where that text goes. The value returned by evaluating | |
643 the form (here @code{bar}) follows on a separate line. | |
644 | |
645 @example | |
646 @group | |
647 (progn (print 'foo) (print 'bar)) | |
648 @print{} foo | |
649 @print{} bar | |
650 @result{} bar | |
651 @end group | |
652 @end example | |
653 | |
654 @node Error Messages | |
655 @subsection Error Messages | |
656 @cindex error message notation | |
657 | |
658 Some examples signal errors. This normally displays an error message | |
659 in the echo area. We show the error message on a line starting with | |
660 @samp{@error{}}. Note that @samp{@error{}} itself does not appear in | |
661 the echo area. | |
662 | |
663 @example | |
664 (+ 23 'x) | |
665 @error{} Wrong type argument: integer-or-marker-p, x | |
666 @end example | |
667 | |
668 @node Buffer Text Notation | |
669 @subsection Buffer Text Notation | |
670 @cindex buffer text notation | |
671 | |
672 Some examples show modifications to text in a buffer, with ``before'' | |
673 and ``after'' versions of the text. These examples show the contents of | |
674 the buffer in question between two lines of dashes containing the buffer | |
675 name. In addition, @samp{@point{}} indicates the location of point. | |
676 (The symbol for point, of course, is not part of the text in the buffer; | |
677 it indicates the place @emph{between} two characters where point is | |
678 located.) | |
679 | |
680 @example | |
681 ---------- Buffer: foo ---------- | |
682 This is the @point{}contents of foo. | |
683 ---------- Buffer: foo ---------- | |
684 | |
685 (insert "changed ") | |
686 @result{} nil | |
687 ---------- Buffer: foo ---------- | |
688 This is the changed @point{}contents of foo. | |
689 ---------- Buffer: foo ---------- | |
690 @end example | |
691 | |
692 @node Format of Descriptions | |
693 @subsection Format of Descriptions | |
694 @cindex description format | |
695 | |
696 Functions, variables, macros, commands, user options, and special | |
697 forms are described in this manual in a uniform format. The first | |
698 line of a description contains the name of the item followed by its | |
699 arguments, if any. | |
700 @ifinfo | |
701 The category---function, variable, or whatever---appears at the | |
702 beginning of the line. | |
703 @end ifinfo | |
704 @iftex | |
705 The category---function, variable, or whatever---is printed next to the | |
706 right margin. | |
707 @end iftex | |
708 The description follows on succeeding lines, sometimes with examples. | |
709 | |
710 @menu | |
711 * A Sample Function Description:: A description of an imaginary | |
712 function, @code{foo}. | |
713 * A Sample Variable Description:: A description of an imaginary | |
714 variable, | |
444 | 715 @code{electric-future-map}. |
428 | 716 @end menu |
717 | |
718 @node A Sample Function Description | |
719 @subsubsection A Sample Function Description | |
720 @cindex function descriptions | |
721 @cindex command descriptions | |
722 @cindex macro descriptions | |
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723 @cindex special operator descriptions |
428 | 724 |
725 In a function description, the name of the function being described | |
726 appears first. It is followed on the same line by a list of parameters. | |
727 The names used for the parameters are also used in the body of the | |
728 description. | |
729 | |
730 The appearance of the keyword @code{&optional} in the parameter list | |
731 indicates that the arguments for subsequent parameters may be omitted | |
732 (omitted parameters default to @code{nil}). Do not write | |
733 @code{&optional} when you call the function. | |
734 | |
735 The keyword @code{&rest} (which will always be followed by a single | |
736 parameter) indicates that any number of arguments can follow. The value | |
737 of the single following parameter will be a list of all these arguments. | |
738 Do not write @code{&rest} when you call the function. | |
739 | |
740 Here is a description of an imaginary function @code{foo}: | |
741 | |
742 @defun foo integer1 &optional integer2 &rest integers | |
743 The function @code{foo} subtracts @var{integer1} from @var{integer2}, | |
744 then adds all the rest of the arguments to the result. If @var{integer2} | |
745 is not supplied, then the number 19 is used by default. | |
746 | |
747 @example | |
748 (foo 1 5 3 9) | |
749 @result{} 16 | |
750 (foo 5) | |
751 @result{} 14 | |
752 @end example | |
753 | |
754 More generally, | |
755 | |
756 @example | |
757 (foo @var{w} @var{x} @var{y}@dots{}) | |
758 @equiv{} | |
759 (+ (- @var{x} @var{w}) @var{y}@dots{}) | |
760 @end example | |
761 @end defun | |
762 | |
763 Any parameter whose name contains the name of a type (e.g., | |
764 @var{integer}, @var{integer1} or @var{buffer}) is expected to be of that | |
765 type. A plural of a type (such as @var{buffers}) often means a list of | |
766 objects of that type. Parameters named @var{object} may be of any type. | |
767 (@xref{Lisp Data Types}, for a list of XEmacs object types.) | |
768 Parameters with other sorts of names (e.g., @var{new-file}) are | |
769 discussed specifically in the description of the function. In some | |
770 sections, features common to parameters of several functions are | |
771 described at the beginning. | |
772 | |
773 @xref{Lambda Expressions}, for a more complete description of optional | |
774 and rest arguments. | |
775 | |
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776 Command, macro, and special operator descriptions have the same format, |
428 | 777 but the word `Function' is replaced by `Command', `Macro', or `Special |
778 Form', respectively. Commands are simply functions that may be called | |
779 interactively; macros process their arguments differently from functions | |
780 (the arguments are not evaluated), but are presented the same way. | |
781 | |
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782 Special operator descriptions use a more complex notation to specify |
428 | 783 optional and repeated parameters because they can break the argument |
784 list down into separate arguments in more complicated ways. | |
785 @samp{@code{@r{[}@var{optional-arg}@r{]}}} means that @var{optional-arg} is | |
786 optional and @samp{@var{repeated-args}@dots{}} stands for zero or more | |
787 arguments. Parentheses are used when several arguments are grouped into | |
788 additional levels of list structure. Here is an example: | |
789 | |
790 @defspec count-loop (@var{var} [@var{from} @var{to} [@var{inc}]]) @var{body}@dots{} | |
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791 This imaginary special operator implements a loop that executes the |
428 | 792 @var{body} forms and then increments the variable @var{var} on each |
793 iteration. On the first iteration, the variable has the value | |
794 @var{from}; on subsequent iterations, it is incremented by 1 (or by | |
795 @var{inc} if that is given). The loop exits before executing @var{body} | |
796 if @var{var} equals @var{to}. Here is an example: | |
797 | |
798 @example | |
799 (count-loop (i 0 10) | |
800 (prin1 i) (princ " ") | |
801 (prin1 (aref vector i)) (terpri)) | |
802 @end example | |
803 | |
804 If @var{from} and @var{to} are omitted, then @var{var} is bound to | |
805 @code{nil} before the loop begins, and the loop exits if @var{var} is | |
806 non-@code{nil} at the beginning of an iteration. Here is an example: | |
807 | |
808 @example | |
809 (count-loop (done) | |
810 (if (pending) | |
811 (fixit) | |
812 (setq done t))) | |
813 @end example | |
814 | |
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815 With this special operator, the arguments @var{from} and @var{to} are |
428 | 816 optional, but must both be present or both absent. If they are present, |
817 @var{inc} may optionally be specified as well. These arguments are | |
818 grouped with the argument @var{var} into a list, to distinguish them | |
819 from @var{body}, which includes all remaining elements of the form. | |
820 @end defspec | |
821 | |
822 @node A Sample Variable Description | |
823 @subsubsection A Sample Variable Description | |
824 @cindex variable descriptions | |
825 @cindex option descriptions | |
826 | |
827 A @dfn{variable} is a name that can hold a value. Although any | |
828 variable can be set by the user, certain variables that exist | |
829 specifically so that users can change them are called @dfn{user | |
830 options}. Ordinary variables and user options are described using a | |
831 format like that for functions except that there are no arguments. | |
832 | |
833 Here is a description of the imaginary @code{electric-future-map} | |
834 variable.@refill | |
835 | |
836 @defvar electric-future-map | |
837 The value of this variable is a full keymap used by Electric Command | |
838 Future mode. The functions in this map allow you to edit commands you | |
839 have not yet thought about executing. | |
840 @end defvar | |
841 | |
842 User option descriptions have the same format, but `Variable' is | |
843 replaced by `User Option'. | |
844 | |
845 @node Acknowledgements | |
846 @section Acknowledgements | |
847 | |
848 This manual was based on the GNU Emacs Lisp Reference Manual, version | |
849 2.4, written by Robert Krawitz, Bil Lewis, Dan LaLiberte, Richard | |
850 M. Stallman and Chris Welty, the volunteers of the GNU manual group, in | |
851 an effort extending over several years. Robert J. Chassell helped to | |
852 review and edit the manual, with the support of the Defense Advanced | |
853 Research Projects Agency, ARPA Order 6082, arranged by Warren A. Hunt, | |
854 Jr. of Computational Logic, Inc. | |
855 | |
856 Ben Wing adapted this manual for XEmacs 19.14 and 20.0, and earlier | |
857 for Lucid Emacs 19.10, XEmacs 19.12, and XEmacs 19.13. He is the sole | |
858 author of many of the manual sections, in particular the XEmacs-specific | |
859 sections: events, faces, extents, glyphs, specifiers, toolbar, menubars, | |
860 scrollbars, dialog boxes, devices, consoles, hash tables, range tables, | |
861 char tables, databases, and others. The section on annotations was | |
862 originally written by Chuck Thompson. Corrections to v3.1 and later were | |
863 done by Martin Buchholz, Steve Baur, and Hrvoje Niksic. | |
864 | |
865 Corrections to the original GNU Emacs Lisp Reference Manual were | |
866 supplied by Karl Berry, Jim Blandy, Bard Bloom, Stephane Boucher, David | |
867 Boyes, Alan Carroll, Richard Davis, Lawrence R. Dodd, Peter Doornbosch, | |
868 David A. Duff, Chris Eich, Beverly Erlebacher, David Eckelkamp, Ralf | |
869 Fassel, Eirik Fuller, Stephen Gildea, Bob Glickstein, Eric Hanchrow, | |
870 George Hartzell, Nathan Hess, Masayuki Ida, Dan Jacobson, Jak Kirman, | |
871 Bob Knighten, Frederick M. Korz, Joe Lammens, Glenn M. Lewis, K. Richard | |
872 Magill, Brian Marick, Roland McGrath, Skip Montanaro, John Gardiner | |
873 Myers, Thomas A. Peterson, Francesco Potorti, Friedrich Pukelsheim, | |
874 Arnold D. Robbins, Raul Rockwell, Per Starback, Shinichirou Sugou, Kimmo | |
875 Suominen, Edward Tharp, Bill Trost, Rickard Westman, Jean White, Matthew | |
876 Wilding, Carl Witty, Dale Worley, Rusty Wright, and David D. Zuhn. |