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1 | @c -*-texinfo-*- |
2 | @c This is part of the GNU Emacs Lisp Reference Manual. | |
367b61a1 | 3 | @c Copyright (C) 1990, 1991, 1992, 1993, 1994, 2002 |
177c0ea7 | 4 | @c Free Software Foundation, Inc. |
83ac6b45 RS |
5 | @c See the file elisp.texi for copying conditions. |
6 | @setfilename ../info/intro | |
7 | ||
892a8f36 | 8 | @c Versino of the manual. |
367b61a1 | 9 | @set VERSION 2.9 |
892a8f36 | 10 | |
e4a29e5a | 11 | @node Introduction, Lisp Data Types, Top, Top |
83ac6b45 | 12 | @comment node-name, next, previous, up |
83ac6b45 RS |
13 | @chapter Introduction |
14 | ||
15 | Most of the GNU Emacs text editor is written in the programming | |
16 | language called Emacs Lisp. You can write new code in Emacs Lisp and | |
17 | install it as an extension to the editor. However, Emacs Lisp is more | |
18 | than a mere ``extension language''; it is a full computer programming | |
19 | language in its own right. You can use it as you would any other | |
20 | programming language. | |
21 | ||
22 | Because Emacs Lisp is designed for use in an editor, it has special | |
23 | features for scanning and parsing text as well as features for handling | |
24 | files, buffers, displays, subprocesses, and so on. Emacs Lisp is | |
25 | closely integrated with the editing facilities; thus, editing commands | |
26 | are functions that can also conveniently be called from Lisp programs, | |
27 | and parameters for customization are ordinary Lisp variables. | |
28 | ||
a9f0a989 RS |
29 | This manual attempts to be a full description of Emacs Lisp. For a |
30 | beginner's introduction to Emacs Lisp, see @cite{An Introduction to | |
31 | Emacs Lisp Programming}, by Bob Chassell, also published by the Free | |
32 | Software Foundation. This manual presumes considerable familiarity with | |
33 | the use of Emacs for editing; see @cite{The GNU Emacs Manual} for this | |
34 | basic information. | |
35 | ||
36 | Generally speaking, the earlier chapters describe features of Emacs | |
37 | Lisp that have counterparts in many programming languages, and later | |
38 | chapters describe features that are peculiar to Emacs Lisp or relate | |
39 | specifically to editing. | |
83ac6b45 | 40 | |
892a8f36 | 41 | This is edition @value{VERSION}. |
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42 | |
43 | @menu | |
44 | * Caveats:: Flaws and a request for help. | |
45 | * Lisp History:: Emacs Lisp is descended from Maclisp. | |
46 | * Conventions:: How the manual is formatted. | |
a9f0a989 | 47 | * Version Info:: Which Emacs version is running? |
83ac6b45 RS |
48 | * Acknowledgements:: The authors, editors, and sponsors of this manual. |
49 | @end menu | |
50 | ||
51 | @node Caveats | |
52 | @section Caveats | |
30db19b9 | 53 | @cindex bugs in this manual |
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54 | |
55 | This manual has gone through numerous drafts. It is nearly complete | |
7791402e RS |
56 | but not flawless. There are a few topics that are not covered, either |
57 | because we consider them secondary (such as most of the individual | |
58 | modes) or because they are yet to be written. Because we are not able | |
59 | to deal with them completely, we have left out several parts | |
60 | intentionally. This includes most information about usage on VMS. | |
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61 | |
62 | The manual should be fully correct in what it does cover, and it is | |
63 | therefore open to criticism on anything it says---from specific examples | |
64 | and descriptive text, to the ordering of chapters and sections. If | |
65 | something is confusing, or you find that you have to look at the sources | |
66 | or experiment to learn something not covered in the manual, then perhaps | |
67 | the manual should be fixed. Please let us know. | |
68 | ||
69 | @iftex | |
a40d4712 PR |
70 | As you use this manual, we ask that you mark pages with corrections so |
71 | you can later look them up and send them to us. If you think of a simple, | |
7791402e | 72 | real-life example for a function or group of functions, please make an |
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73 | effort to write it up and send it in. Please reference any comments to |
74 | the chapter name, section name, and function name, as appropriate, since | |
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75 | page numbers and chapter and section numbers will change and we may have |
76 | trouble finding the text you are talking about. Also state the number | |
77 | of the edition you are criticizing. | |
83ac6b45 | 78 | @end iftex |
37680279 | 79 | @ifnottex |
83ac6b45 RS |
80 | |
81 | As you use this manual, we ask that you send corrections as soon as you | |
82 | find them. If you think of a simple, real life example for a function | |
83 | or group of functions, please make an effort to write it up and send it | |
84 | in. Please reference any comments to the node name and function or | |
85 | variable name, as appropriate. Also state the number of the edition | |
a40d4712 | 86 | you are criticizing. |
37680279 | 87 | @end ifnottex |
83ac6b45 | 88 | |
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89 | @cindex bugs |
90 | @cindex suggestions | |
83ac6b45 RS |
91 | Please mail comments and corrections to |
92 | ||
93 | @example | |
a9f0a989 | 94 | bug-lisp-manual@@gnu.org |
83ac6b45 RS |
95 | @end example |
96 | ||
97 | @noindent | |
98 | We let mail to this list accumulate unread until someone decides to | |
99 | apply the corrections. Months, and sometimes years, go by between | |
100 | updates. So please attach no significance to the lack of a reply---your | |
101 | mail @emph{will} be acted on in due time. If you want to contact the | |
102 | Emacs maintainers more quickly, send mail to | |
a9f0a989 | 103 | @code{bug-gnu-emacs@@gnu.org}. |
83ac6b45 | 104 | |
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105 | @node Lisp History |
106 | @section Lisp History | |
107 | @cindex Lisp history | |
108 | ||
a9f0a989 | 109 | Lisp (LISt Processing language) was first developed in the late 1950s |
83ac6b45 | 110 | at the Massachusetts Institute of Technology for research in artificial |
a9f0a989 | 111 | intelligence. The great power of the Lisp language makes it ideal |
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112 | for other purposes as well, such as writing editing commands. |
113 | ||
114 | @cindex Maclisp | |
115 | @cindex Common Lisp | |
116 | Dozens of Lisp implementations have been built over the years, each | |
117 | with its own idiosyncrasies. Many of them were inspired by Maclisp, | |
a9f0a989 | 118 | which was written in the 1960s at MIT's Project MAC. Eventually the |
7791402e | 119 | implementors of the descendants of Maclisp came together and developed a |
a9f0a989 | 120 | standard for Lisp systems, called Common Lisp. In the meantime, Gerry |
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121 | Sussman and Guy Steele at MIT developed a simplified but very powerful |
122 | dialect of Lisp, called Scheme. | |
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123 | |
124 | GNU Emacs Lisp is largely inspired by Maclisp, and a little by Common | |
125 | Lisp. If you know Common Lisp, you will notice many similarities. | |
a9f0a989 | 126 | However, many features of Common Lisp have been omitted or |
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127 | simplified in order to reduce the memory requirements of GNU Emacs. |
128 | Sometimes the simplifications are so drastic that a Common Lisp user | |
129 | might be very confused. We will occasionally point out how GNU Emacs | |
130 | Lisp differs from Common Lisp. If you don't know Common Lisp, don't | |
131 | worry about it; this manual is self-contained. | |
132 | ||
a9f0a989 RS |
133 | @pindex cl |
134 | A certain amount of Common Lisp emulation is available via the | |
0eeca3c1 | 135 | @file{cl} library. @inforef{Top, Overview, cl}. |
a9f0a989 | 136 | |
969fe9b5 | 137 | Emacs Lisp is not at all influenced by Scheme; but the GNU project has |
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138 | an implementation of Scheme, called Guile. We use Guile in all new GNU |
139 | software that calls for extensibility. | |
969fe9b5 | 140 | |
83ac6b45 RS |
141 | @node Conventions |
142 | @section Conventions | |
143 | ||
144 | This section explains the notational conventions that are used in this | |
145 | manual. You may want to skip this section and refer back to it later. | |
146 | ||
147 | @menu | |
148 | * Some Terms:: Explanation of terms we use in this manual. | |
149 | * nil and t:: How the symbols @code{nil} and @code{t} are used. | |
150 | * Evaluation Notation:: The format we use for examples of evaluation. | |
a9f0a989 | 151 | * Printing Notation:: The format we use when examples print text. |
83ac6b45 RS |
152 | * Error Messages:: The format we use for examples of errors. |
153 | * Buffer Text Notation:: The format we use for buffer contents in examples. | |
154 | * Format of Descriptions:: Notation for describing functions, variables, etc. | |
155 | @end menu | |
156 | ||
157 | @node Some Terms | |
158 | @subsection Some Terms | |
159 | ||
160 | Throughout this manual, the phrases ``the Lisp reader'' and ``the Lisp | |
a9f0a989 RS |
161 | printer'' refer to those routines in Lisp that convert textual |
162 | representations of Lisp objects into actual Lisp objects, and vice | |
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163 | versa. @xref{Printed Representation}, for more details. You, the |
164 | person reading this manual, are thought of as ``the programmer'' and are | |
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165 | addressed as ``you''. ``The user'' is the person who uses Lisp |
166 | programs, including those you write. | |
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167 | |
168 | @cindex fonts | |
8241495d RS |
169 | Examples of Lisp code are formatted like this: @code{(list 1 2 3)}. |
170 | Names that represent metasyntactic variables, or arguments to a function | |
171 | being described, are formatted like this: @var{first-number}. | |
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172 | |
173 | @node nil and t | |
174 | @subsection @code{nil} and @code{t} | |
175 | @cindex @code{nil}, uses of | |
176 | @cindex truth value | |
177 | @cindex boolean | |
178 | @cindex false | |
179 | ||
bfe721d1 | 180 | In Lisp, the symbol @code{nil} has three separate meanings: it |
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181 | is a symbol with the name @samp{nil}; it is the logical truth value |
182 | @var{false}; and it is the empty list---the list of zero elements. | |
183 | When used as a variable, @code{nil} always has the value @code{nil}. | |
184 | ||
185 | As far as the Lisp reader is concerned, @samp{()} and @samp{nil} are | |
186 | identical: they stand for the same object, the symbol @code{nil}. The | |
187 | different ways of writing the symbol are intended entirely for human | |
188 | readers. After the Lisp reader has read either @samp{()} or @samp{nil}, | |
189 | there is no way to determine which representation was actually written | |
190 | by the programmer. | |
191 | ||
192 | In this manual, we use @code{()} when we wish to emphasize that it | |
193 | means the empty list, and we use @code{nil} when we wish to emphasize | |
194 | that it means the truth value @var{false}. That is a good convention to use | |
195 | in Lisp programs also. | |
196 | ||
197 | @example | |
198 | (cons 'foo ()) ; @r{Emphasize the empty list} | |
199 | (not nil) ; @r{Emphasize the truth value @var{false}} | |
200 | @end example | |
201 | ||
202 | @cindex @code{t} and truth | |
203 | @cindex true | |
204 | In contexts where a truth value is expected, any non-@code{nil} value | |
205 | is considered to be @var{true}. However, @code{t} is the preferred way | |
206 | to represent the truth value @var{true}. When you need to choose a | |
207 | value which represents @var{true}, and there is no other basis for | |
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208 | choosing, use @code{t}. The symbol @code{t} always has the value |
209 | @code{t}. | |
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210 | |
211 | In Emacs Lisp, @code{nil} and @code{t} are special symbols that always | |
212 | evaluate to themselves. This is so that you do not need to quote them | |
213 | to use them as constants in a program. An attempt to change their | |
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214 | values results in a @code{setting-constant} error. The same is true of |
215 | any symbol whose name starts with a colon (@samp{:}). @xref{Constant | |
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216 | Variables}. |
217 | ||
218 | @node Evaluation Notation | |
219 | @subsection Evaluation Notation | |
220 | @cindex evaluation notation | |
221 | @cindex documentation notation | |
222 | ||
223 | A Lisp expression that you can evaluate is called a @dfn{form}. | |
224 | Evaluating a form always produces a result, which is a Lisp object. In | |
225 | the examples in this manual, this is indicated with @samp{@result{}}: | |
226 | ||
227 | @example | |
228 | (car '(1 2)) | |
229 | @result{} 1 | |
230 | @end example | |
231 | ||
232 | @noindent | |
233 | You can read this as ``@code{(car '(1 2))} evaluates to 1''. | |
234 | ||
235 | When a form is a macro call, it expands into a new form for Lisp to | |
236 | evaluate. We show the result of the expansion with | |
a9f0a989 | 237 | @samp{@expansion{}}. We may or may not show the result of the |
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238 | evaluation of the expanded form. |
239 | ||
240 | @example | |
241 | (third '(a b c)) | |
242 | @expansion{} (car (cdr (cdr '(a b c)))) | |
243 | @result{} c | |
244 | @end example | |
245 | ||
7791402e | 246 | Sometimes to help describe one form we show another form that |
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247 | produces identical results. The exact equivalence of two forms is |
248 | indicated with @samp{@equiv{}}. | |
249 | ||
250 | @example | |
251 | (make-sparse-keymap) @equiv{} (list 'keymap) | |
252 | @end example | |
253 | ||
254 | @node Printing Notation | |
255 | @subsection Printing Notation | |
256 | @cindex printing notation | |
257 | ||
258 | Many of the examples in this manual print text when they are | |
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259 | evaluated. If you execute example code in a Lisp Interaction buffer |
260 | (such as the buffer @samp{*scratch*}), the printed text is inserted into | |
261 | the buffer. If you execute the example by other means (such as by | |
262 | evaluating the function @code{eval-region}), the printed text is | |
79ddc9c9 | 263 | displayed in the echo area. |
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264 | |
265 | Examples in this manual indicate printed text with @samp{@print{}}, | |
266 | irrespective of where that text goes. The value returned by evaluating | |
267 | the form (here @code{bar}) follows on a separate line. | |
268 | ||
269 | @example | |
270 | @group | |
271 | (progn (print 'foo) (print 'bar)) | |
272 | @print{} foo | |
273 | @print{} bar | |
274 | @result{} bar | |
275 | @end group | |
276 | @end example | |
277 | ||
278 | @node Error Messages | |
279 | @subsection Error Messages | |
280 | @cindex error message notation | |
281 | ||
282 | Some examples signal errors. This normally displays an error message | |
283 | in the echo area. We show the error message on a line starting with | |
284 | @samp{@error{}}. Note that @samp{@error{}} itself does not appear in | |
285 | the echo area. | |
286 | ||
287 | @example | |
288 | (+ 23 'x) | |
f9f59935 | 289 | @error{} Wrong type argument: number-or-marker-p, x |
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290 | @end example |
291 | ||
292 | @node Buffer Text Notation | |
293 | @subsection Buffer Text Notation | |
294 | @cindex buffer text notation | |
295 | ||
8241495d RS |
296 | Some examples describe modifications to the contents of a buffer, by |
297 | showing the ``before'' and ``after'' versions of the text. These | |
298 | examples show the contents of the buffer in question between two lines | |
299 | of dashes containing the buffer name. In addition, @samp{@point{}} | |
300 | indicates the location of point. (The symbol for point, of course, is | |
301 | not part of the text in the buffer; it indicates the place | |
302 | @emph{between} two characters where point is currently located.) | |
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303 | |
304 | @example | |
305 | ---------- Buffer: foo ---------- | |
306 | This is the @point{}contents of foo. | |
307 | ---------- Buffer: foo ---------- | |
308 | ||
309 | (insert "changed ") | |
310 | @result{} nil | |
311 | ---------- Buffer: foo ---------- | |
312 | This is the changed @point{}contents of foo. | |
313 | ---------- Buffer: foo ---------- | |
314 | @end example | |
315 | ||
316 | @node Format of Descriptions | |
317 | @subsection Format of Descriptions | |
318 | @cindex description format | |
319 | ||
320 | Functions, variables, macros, commands, user options, and special | |
321 | forms are described in this manual in a uniform format. The first | |
322 | line of a description contains the name of the item followed by its | |
323 | arguments, if any. | |
37680279 | 324 | @ifnottex |
83ac6b45 RS |
325 | The category---function, variable, or whatever---appears at the |
326 | beginning of the line. | |
37680279 | 327 | @end ifnottex |
83ac6b45 RS |
328 | @iftex |
329 | The category---function, variable, or whatever---is printed next to the | |
330 | right margin. | |
331 | @end iftex | |
332 | The description follows on succeeding lines, sometimes with examples. | |
333 | ||
334 | @menu | |
335 | * A Sample Function Description:: A description of an imaginary | |
336 | function, @code{foo}. | |
337 | * A Sample Variable Description:: A description of an imaginary | |
338 | variable, | |
177c0ea7 | 339 | @code{electric-future-map}. |
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340 | @end menu |
341 | ||
342 | @node A Sample Function Description | |
343 | @subsubsection A Sample Function Description | |
344 | @cindex function descriptions | |
345 | @cindex command descriptions | |
346 | @cindex macro descriptions | |
347 | @cindex special form descriptions | |
348 | ||
349 | In a function description, the name of the function being described | |
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350 | appears first. It is followed on the same line by a list of argument |
351 | names. These names are also used in the body of the description, to | |
352 | stand for the values of the arguments. | |
83ac6b45 | 353 | |
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354 | The appearance of the keyword @code{&optional} in the argument list |
355 | indicates that the subsequent arguments may be omitted (omitted | |
356 | arguments default to @code{nil}). Do not write @code{&optional} when | |
357 | you call the function. | |
83ac6b45 | 358 | |
a9f0a989 RS |
359 | The keyword @code{&rest} (which must be followed by a single argument |
360 | name) indicates that any number of arguments can follow. The single | |
361 | following argument name will have a value, as a variable, which is a | |
362 | list of all these remaining arguments. Do not write @code{&rest} when | |
363 | you call the function. | |
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364 | |
365 | Here is a description of an imaginary function @code{foo}: | |
366 | ||
367 | @defun foo integer1 &optional integer2 &rest integers | |
368 | The function @code{foo} subtracts @var{integer1} from @var{integer2}, | |
369 | then adds all the rest of the arguments to the result. If @var{integer2} | |
370 | is not supplied, then the number 19 is used by default. | |
371 | ||
372 | @example | |
373 | (foo 1 5 3 9) | |
374 | @result{} 16 | |
375 | (foo 5) | |
376 | @result{} 14 | |
377 | @end example | |
378 | ||
7dd3d99f | 379 | @need 1500 |
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380 | More generally, |
381 | ||
382 | @example | |
383 | (foo @var{w} @var{x} @var{y}@dots{}) | |
384 | @equiv{} | |
385 | (+ (- @var{x} @var{w}) @var{y}@dots{}) | |
386 | @end example | |
387 | @end defun | |
388 | ||
969fe9b5 | 389 | Any argument whose name contains the name of a type (e.g., |
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390 | @var{integer}, @var{integer1} or @var{buffer}) is expected to be of that |
391 | type. A plural of a type (such as @var{buffers}) often means a list of | |
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392 | objects of that type. Arguments named @var{object} may be of any type. |
393 | (@xref{Lisp Data Types}, for a list of Emacs object types.) Arguments | |
394 | with other sorts of names (e.g., @var{new-file}) are discussed | |
395 | specifically in the description of the function. In some sections, | |
396 | features common to the arguments of several functions are described at | |
397 | the beginning. | |
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398 | |
399 | @xref{Lambda Expressions}, for a more complete description of optional | |
400 | and rest arguments. | |
401 | ||
402 | Command, macro, and special form descriptions have the same format, | |
403 | but the word `Function' is replaced by `Command', `Macro', or `Special | |
404 | Form', respectively. Commands are simply functions that may be called | |
405 | interactively; macros process their arguments differently from functions | |
406 | (the arguments are not evaluated), but are presented the same way. | |
407 | ||
408 | Special form descriptions use a more complex notation to specify | |
969fe9b5 | 409 | optional and repeated arguments because they can break the argument |
83ac6b45 | 410 | list down into separate arguments in more complicated ways. |
a9f0a989 | 411 | @samp{@r{[}@var{optional-arg}@r{]}} means that @var{optional-arg} is |
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412 | optional and @samp{@var{repeated-args}@dots{}} stands for zero or more |
413 | arguments. Parentheses are used when several arguments are grouped into | |
414 | additional levels of list structure. Here is an example: | |
415 | ||
416 | @defspec count-loop (@var{var} [@var{from} @var{to} [@var{inc}]]) @var{body}@dots{} | |
417 | This imaginary special form implements a loop that executes the | |
418 | @var{body} forms and then increments the variable @var{var} on each | |
419 | iteration. On the first iteration, the variable has the value | |
a9f0a989 | 420 | @var{from}; on subsequent iterations, it is incremented by one (or by |
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421 | @var{inc} if that is given). The loop exits before executing @var{body} |
422 | if @var{var} equals @var{to}. Here is an example: | |
423 | ||
424 | @example | |
425 | (count-loop (i 0 10) | |
426 | (prin1 i) (princ " ") | |
969fe9b5 RS |
427 | (prin1 (aref vector i)) |
428 | (terpri)) | |
83ac6b45 RS |
429 | @end example |
430 | ||
a9f0a989 | 431 | If @var{from} and @var{to} are omitted, @var{var} is bound to |
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432 | @code{nil} before the loop begins, and the loop exits if @var{var} is |
433 | non-@code{nil} at the beginning of an iteration. Here is an example: | |
434 | ||
435 | @example | |
436 | (count-loop (done) | |
437 | (if (pending) | |
438 | (fixit) | |
439 | (setq done t))) | |
440 | @end example | |
441 | ||
442 | In this special form, the arguments @var{from} and @var{to} are | |
443 | optional, but must both be present or both absent. If they are present, | |
444 | @var{inc} may optionally be specified as well. These arguments are | |
445 | grouped with the argument @var{var} into a list, to distinguish them | |
446 | from @var{body}, which includes all remaining elements of the form. | |
447 | @end defspec | |
448 | ||
449 | @node A Sample Variable Description | |
450 | @subsubsection A Sample Variable Description | |
451 | @cindex variable descriptions | |
452 | @cindex option descriptions | |
453 | ||
454 | A @dfn{variable} is a name that can hold a value. Although any | |
455 | variable can be set by the user, certain variables that exist | |
456 | specifically so that users can change them are called @dfn{user | |
457 | options}. Ordinary variables and user options are described using a | |
458 | format like that for functions except that there are no arguments. | |
459 | ||
460 | Here is a description of the imaginary @code{electric-future-map} | |
461 | variable.@refill | |
462 | ||
463 | @defvar electric-future-map | |
464 | The value of this variable is a full keymap used by Electric Command | |
465 | Future mode. The functions in this map allow you to edit commands you | |
466 | have not yet thought about executing. | |
467 | @end defvar | |
468 | ||
469 | User option descriptions have the same format, but `Variable' is | |
470 | replaced by `User Option'. | |
471 | ||
969fe9b5 RS |
472 | @node Version Info |
473 | @section Version Information | |
474 | ||
a9f0a989 RS |
475 | These facilities provide information about which version of Emacs is |
476 | in use. | |
969fe9b5 | 477 | |
8bbf587d | 478 | @deffn Command emacs-version &optional here |
969fe9b5 RS |
479 | This function returns a string describing the version of Emacs that is |
480 | running. It is useful to include this string in bug reports. | |
481 | ||
a9f0a989 | 482 | @smallexample |
969fe9b5 RS |
483 | @group |
484 | (emacs-version) | |
485 | @result{} "GNU Emacs 20.3.5 (i486-pc-linux-gnulibc1, X toolkit) | |
486 | of Sat Feb 14 1998 on psilocin.gnu.org" | |
487 | @end group | |
a9f0a989 | 488 | @end smallexample |
969fe9b5 | 489 | |
8bbf587d RS |
490 | If @var{here} is non-@code{nil}, it inserts the text in the buffer |
491 | before point, and returns @code{nil}. Called interactively, the | |
492 | function prints the same information in the echo area, but giving a | |
493 | prefix argument makes @var{here} non-@code{nil}. | |
969fe9b5 RS |
494 | @end deffn |
495 | ||
496 | @defvar emacs-build-time | |
a9f0a989 RS |
497 | The value of this variable indicates the time at which Emacs was built |
498 | at the local site. It is a list of three integers, like the value | |
499 | of @code{current-time} (@pxref{Time of Day}). | |
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500 | |
501 | @example | |
502 | @group | |
503 | emacs-build-time | |
a9f0a989 | 504 | @result{} (13623 62065 344633) |
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505 | @end group |
506 | @end example | |
507 | @end defvar | |
508 | ||
509 | @defvar emacs-version | |
510 | The value of this variable is the version of Emacs being run. It is a | |
511 | string such as @code{"20.3.1"}. The last number in this string is not | |
512 | really part of the Emacs release version number; it is incremented each | |
aab28c42 | 513 | time you build Emacs in any given directory. A value with four numeric |
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514 | components, such as @code{"20.3.9.1"}, indicates an unreleased test |
515 | version. | |
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516 | @end defvar |
517 | ||
a9f0a989 | 518 | The following two variables have existed since Emacs version 19.23: |
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519 | |
520 | @defvar emacs-major-version | |
521 | The major version number of Emacs, as an integer. For Emacs version | |
522 | 20.3, the value is 20. | |
523 | @end defvar | |
524 | ||
525 | @defvar emacs-minor-version | |
526 | The minor version number of Emacs, as an integer. For Emacs version | |
527 | 20.3, the value is 3. | |
528 | @end defvar | |
529 | ||
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530 | @node Acknowledgements |
531 | @section Acknowledgements | |
532 | ||
533 | This manual was written by Robert Krawitz, Bil Lewis, Dan LaLiberte, | |
534 | Richard M. Stallman and Chris Welty, the volunteers of the GNU manual | |
535 | group, in an effort extending over several years. Robert J. Chassell | |
536 | helped to review and edit the manual, with the support of the Defense | |
537 | Advanced Research Projects Agency, ARPA Order 6082, arranged by Warren | |
a40d4712 | 538 | A. Hunt, Jr.@: of Computational Logic, Inc. |
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539 | |
540 | Corrections were supplied by Karl Berry, Jim Blandy, Bard Bloom, | |
541 | Stephane Boucher, David Boyes, Alan Carroll, Richard Davis, Lawrence | |
542 | R. Dodd, Peter Doornbosch, David A. Duff, Chris Eich, Beverly | |
543 | Erlebacher, David Eckelkamp, Ralf Fassel, Eirik Fuller, Stephen Gildea, | |
544 | Bob Glickstein, Eric Hanchrow, George Hartzell, Nathan Hess, Masayuki | |
545 | Ida, Dan Jacobson, Jak Kirman, Bob Knighten, Frederick M. Korz, Joe | |
546 | Lammens, Glenn M. Lewis, K. Richard Magill, Brian Marick, Roland | |
547 | McGrath, Skip Montanaro, John Gardiner Myers, Thomas A. Peterson, | |
548 | Francesco Potorti, Friedrich Pukelsheim, Arnold D. Robbins, Raul | |
a40d4712 | 549 | Rockwell, Per Starb@"ack, Shinichirou Sugou, Kimmo Suominen, Edward Tharp, |
83ac6b45 RS |
550 | Bill Trost, Rickard Westman, Jean White, Matthew Wilding, Carl Witty, |
551 | Dale Worley, Rusty Wright, and David D. Zuhn. | |
ab5796a9 MB |
552 | |
553 | @ignore | |
554 | arch-tag: d156593f-82f8-4708-a844-204e48f7f2aa | |
555 | @end ignore |