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1 @c This is part of the Emacs manual.
2 @c Copyright (C) 1985,86,87,93,94,95,97,2000,2001, 2002, 2004
3 @c Free Software Foundation, Inc.
4 @c See file emacs.texi for copying conditions.
5 @node Text, Programs, Indentation, Top
6 @chapter Commands for Human Languages
7 @cindex text
8 @cindex manipulating text
9
10 The term @dfn{text} has two widespread meanings in our area of the
11 computer field. One is data that is a sequence of characters. Any file
12 that you edit with Emacs is text, in this sense of the word. The other
13 meaning is more restrictive: a sequence of characters in a human language
14 for humans to read (possibly after processing by a text formatter), as
15 opposed to a program or commands for a program.
16
17 Human languages have syntactic/stylistic conventions that can be
18 supported or used to advantage by editor commands: conventions involving
19 words, sentences, paragraphs, and capital letters. This chapter
20 describes Emacs commands for all of these things. There are also
21 commands for @dfn{filling}, which means rearranging the lines of a
22 paragraph to be approximately equal in length. The commands for moving
23 over and killing words, sentences and paragraphs, while intended
24 primarily for editing text, are also often useful for editing programs.
25
26 Emacs has several major modes for editing human-language text. If the
27 file contains text pure and simple, use Text mode, which customizes
28 Emacs in small ways for the syntactic conventions of text. Outline mode
29 provides special commands for operating on text with an outline
30 structure.
31 @iftex
32 @xref{Outline Mode}.
33 @end iftex
34
35 For text which contains embedded commands for text formatters, Emacs
36 has other major modes, each for a particular text formatter. Thus, for
37 input to @TeX{}, you would use @TeX{}
38 @iftex
39 mode (@pxref{TeX Mode}).
40 @end iftex
41 @ifinfo
42 mode.
43 @end ifinfo
44 For input to nroff, use Nroff mode.
45
46 Instead of using a text formatter, you can edit formatted text in
47 WYSIWYG style (``what you see is what you get''), with Enriched mode.
48 Then the formatting appears on the screen in Emacs while you edit.
49 @iftex
50 @xref{Formatted Text}.
51 @end iftex
52
53 @cindex skeletons
54 @cindex templates
55 @cindex autotyping
56 @cindex automatic typing
57 The ``automatic typing'' features may be useful when writing text.
58 @inforef{Top,, autotype}.
59
60 @menu
61 * Words:: Moving over and killing words.
62 * Sentences:: Moving over and killing sentences.
63 * Paragraphs:: Moving over paragraphs.
64 * Pages:: Moving over pages.
65 * Filling:: Filling or justifying text.
66 * Case:: Changing the case of text.
67 * Text Mode:: The major modes for editing text files.
68 * Outline Mode:: Editing outlines.
69 * TeX Mode:: Editing input to the formatter TeX.
70 * HTML Mode:: Editing HTML, SGML, and XML files.
71 * Nroff Mode:: Editing input to the formatter nroff.
72 * Formatted Text:: Editing formatted text directly in WYSIWYG fashion.
73 * Text Based Tables:: Editing text-based tables in WYSIWYG fashion.
74 @end menu
75
76 @node Words
77 @section Words
78 @cindex words
79 @cindex Meta commands and words
80
81 Emacs has commands for moving over or operating on words. By convention,
82 the keys for them are all Meta characters.
83
84 @table @kbd
85 @item M-f
86 Move forward over a word (@code{forward-word}).
87 @item M-b
88 Move backward over a word (@code{backward-word}).
89 @item M-d
90 Kill up to the end of a word (@code{kill-word}).
91 @item M-@key{DEL}
92 Kill back to the beginning of a word (@code{backward-kill-word}).
93 @item M-@@
94 Mark the end of the next word (@code{mark-word}).
95 @item M-t
96 Transpose two words or drag a word across other words
97 (@code{transpose-words}).
98 @end table
99
100 Notice how these keys form a series that parallels the character-based
101 @kbd{C-f}, @kbd{C-b}, @kbd{C-d}, @key{DEL} and @kbd{C-t}. @kbd{M-@@} is
102 cognate to @kbd{C-@@}, which is an alias for @kbd{C-@key{SPC}}.
103
104 @kindex M-f
105 @kindex M-b
106 @findex forward-word
107 @findex backward-word
108 The commands @kbd{M-f} (@code{forward-word}) and @kbd{M-b}
109 (@code{backward-word}) move forward and backward over words. These
110 Meta characters are thus analogous to the corresponding control
111 characters, @kbd{C-f} and @kbd{C-b}, which move over single characters
112 in the text. The analogy extends to numeric arguments, which serve as
113 repeat counts. @kbd{M-f} with a negative argument moves backward, and
114 @kbd{M-b} with a negative argument moves forward. Forward motion
115 stops right after the last letter of the word, while backward motion
116 stops right before the first letter.@refill
117
118 @kindex M-d
119 @findex kill-word
120 @kbd{M-d} (@code{kill-word}) kills the word after point. To be
121 precise, it kills everything from point to the place @kbd{M-f} would
122 move to. Thus, if point is in the middle of a word, @kbd{M-d} kills
123 just the part after point. If some punctuation comes between point and the
124 next word, it is killed along with the word. (If you wish to kill only the
125 next word but not the punctuation before it, simply do @kbd{M-f} to get
126 the end, and kill the word backwards with @kbd{M-@key{DEL}}.)
127 @kbd{M-d} takes arguments just like @kbd{M-f}.
128
129 @findex backward-kill-word
130 @kindex M-DEL
131 @kbd{M-@key{DEL}} (@code{backward-kill-word}) kills the word before
132 point. It kills everything from point back to where @kbd{M-b} would
133 move to. If point is after the space in @w{@samp{FOO, BAR}}, then
134 @w{@samp{FOO, }} is killed. (If you wish to kill just @samp{FOO}, and
135 not the comma and the space, use @kbd{M-b M-d} instead of
136 @kbd{M-@key{DEL}}.)
137
138 @c Don't index M-t and transpose-words here, they are indexed in
139 @c fixit.texi, in the node "Transpose".
140 @c @kindex M-t
141 @c @findex transpose-words
142 @kbd{M-t} (@code{transpose-words}) exchanges the word before or
143 containing point with the following word. The delimiter characters between
144 the words do not move. For example, @w{@samp{FOO, BAR}} transposes into
145 @w{@samp{BAR, FOO}} rather than @samp{@w{BAR FOO,}}. @xref{Transpose}, for
146 more on transposition and on arguments to transposition commands.
147
148 @kindex M-@@
149 @findex mark-word
150 To operate on the next @var{n} words with an operation which applies
151 between point and mark, you can either set the mark at point and then move
152 over the words, or you can use the command @kbd{M-@@} (@code{mark-word})
153 which does not move point, but sets the mark where @kbd{M-f} would move
154 to. @kbd{M-@@} accepts a numeric argument that says how many words to
155 scan for the place to put the mark. In Transient Mark mode, this command
156 activates the mark.
157
158 The word commands' understanding of syntax is completely controlled by
159 the syntax table. Any character can, for example, be declared to be a word
160 delimiter. @xref{Syntax}.
161
162 @node Sentences
163 @section Sentences
164 @cindex sentences
165 @cindex manipulating sentences
166
167 The Emacs commands for manipulating sentences and paragraphs are mostly
168 on Meta keys, so as to be like the word-handling commands.
169
170 @table @kbd
171 @item M-a
172 Move back to the beginning of the sentence (@code{backward-sentence}).
173 @item M-e
174 Move forward to the end of the sentence (@code{forward-sentence}).
175 @item M-k
176 Kill forward to the end of the sentence (@code{kill-sentence}).
177 @item C-x @key{DEL}
178 Kill back to the beginning of the sentence (@code{backward-kill-sentence}).
179 @end table
180
181 @kindex M-a
182 @kindex M-e
183 @findex backward-sentence
184 @findex forward-sentence
185 The commands @kbd{M-a} and @kbd{M-e} (@code{backward-sentence} and
186 @code{forward-sentence}) move to the beginning and end of the current
187 sentence, respectively. They were chosen to resemble @kbd{C-a} and
188 @kbd{C-e}, which move to the beginning and end of a line. Unlike
189 them, @kbd{M-a} and @kbd{M-e} move over successive sentences if
190 repeated.
191
192 Moving backward over a sentence places point just before the first
193 character of the sentence; moving forward places point right after the
194 punctuation that ends the sentence. Neither one moves over the
195 whitespace at the sentence boundary.
196
197 @kindex M-k
198 @kindex C-x DEL
199 @findex kill-sentence
200 @findex backward-kill-sentence
201 Just as @kbd{C-a} and @kbd{C-e} have a kill command, @kbd{C-k}, to go
202 with them, so @kbd{M-a} and @kbd{M-e} have a corresponding kill command
203 @kbd{M-k} (@code{kill-sentence}) which kills from point to the end of
204 the sentence. With minus one as an argument it kills back to the
205 beginning of the sentence. Larger arguments serve as a repeat count.
206 There is also a command, @kbd{C-x @key{DEL}}
207 (@code{backward-kill-sentence}), for killing back to the beginning of a
208 sentence. This command is useful when you change your mind in the
209 middle of composing text.@refill
210
211 The sentence commands assume that you follow the American typist's
212 convention of putting two spaces at the end of a sentence; they consider
213 a sentence to end wherever there is a @samp{.}, @samp{?} or @samp{!}
214 followed by the end of a line or two spaces, with any number of
215 @samp{)}, @samp{]}, @samp{'}, or @samp{"} characters allowed in between.
216 A sentence also begins or ends wherever a paragraph begins or ends.
217
218 @vindex sentence-end
219 The variable @code{sentence-end} controls recognition of the end of
220 a sentence. If non-@code{nil}, it is a regexp that matches the last
221 few characters of a sentence, together with the whitespace following
222 the sentence. If the value is @code{nil}, the default, then Emacs
223 computes the regexp according to various criteria. The result is
224 normally similar to the following regexp:
225
226 @example
227 "[.?!][]\"')]*\\($\\| $\\|\t\\| \\)[ \t\n]*"
228 @end example
229
230 @noindent
231 This example is explained in the section on regexps. @xref{Regexps}.
232
233 If you want to use just one space between sentences, you should
234 set @code{sentence-end} to this value:
235
236 @example
237 "[.?!][]\"')]*\\($\\|\t\\| \\)[ \t\n]*"
238 @end example
239
240 @noindent
241 This is what setting the variable @code{sentence-end-double-space} to
242 @code{nil} automatically does. But note that this makes it impossible
243 to distinguish between periods that end sentences and those that
244 indicate abbreviations.
245
246 @node Paragraphs
247 @section Paragraphs
248 @cindex paragraphs
249 @cindex manipulating paragraphs
250 @kindex M-@{
251 @kindex M-@}
252 @findex backward-paragraph
253 @findex forward-paragraph
254
255 The Emacs commands for manipulating paragraphs are also Meta keys.
256
257 @table @kbd
258 @item M-@{
259 Move back to previous paragraph beginning (@code{backward-paragraph}).
260 @item M-@}
261 Move forward to next paragraph end (@code{forward-paragraph}).
262 @item M-h
263 Put point and mark around this or next paragraph (@code{mark-paragraph}).
264 @end table
265
266 @kbd{M-@{} moves to the beginning of the current or previous
267 paragraph, while @kbd{M-@}} moves to the end of the current or next
268 paragraph. Blank lines and text-formatter command lines separate
269 paragraphs and are not considered part of any paragraph. In Indented
270 Text mode, but not in Text mode, an indented line also starts a new
271 paragraph. If there is a blank line before the paragraph, @kbd{M-@{}
272 moves to the blank line, because that is convenient in practice.
273
274 In major modes for programs, paragraphs begin and end only at blank
275 lines. This makes the paragraph commands continue to be useful even
276 though there are no paragraphs per se.
277
278 When there is a fill prefix, then paragraphs are delimited by all lines
279 which don't start with the fill prefix. @xref{Filling}.
280
281 @kindex M-h
282 @findex mark-paragraph
283 When you wish to operate on a paragraph, you can use the command
284 @kbd{M-h} (@code{mark-paragraph}) to set the region around it. Thus,
285 for example, @kbd{M-h C-w} kills the paragraph around or after point.
286 The @kbd{M-h} command puts point at the beginning and mark at the end of
287 the paragraph point was in. In Transient Mark mode, it activates the
288 mark. If point is between paragraphs (in a run of blank lines, or at a
289 boundary), the paragraph following point is surrounded by point and
290 mark. If there are blank lines preceding the first line of the
291 paragraph, one of these blank lines is included in the region.
292
293 @vindex paragraph-start
294 @vindex paragraph-separate
295 The precise definition of a paragraph boundary is controlled by the
296 variables @code{paragraph-separate} and @code{paragraph-start}. The
297 value of @code{paragraph-start} is a regexp that should match any line
298 that either starts or separates paragraphs. The value of
299 @code{paragraph-separate} is another regexp that should match only lines
300 that separate paragraphs without being part of any paragraph (for
301 example, blank lines). Lines that start a new paragraph and are
302 contained in it must match only @code{paragraph-start}, not
303 @code{paragraph-separate}. Each regular expression must match at the
304 left margin. For example, in Fundamental mode, @code{paragraph-start}
305 is @w{@code{"\f\\|[ \t]*$"}}, and @code{paragraph-separate} is
306 @w{@code{"[ \t\f]*$"}}.
307
308 Normally it is desirable for page boundaries to separate paragraphs.
309 The default values of these variables recognize the usual separator for
310 pages.
311
312 @node Pages
313 @section Pages
314
315 @cindex pages
316 @cindex formfeed
317 Files are often thought of as divided into @dfn{pages} by the
318 @dfn{formfeed} character (@acronym{ASCII} control-L, octal code 014).
319 When you print hardcopy for a file, this character forces a page break;
320 thus, each page of the file goes on a separate page on paper. Most Emacs
321 commands treat the page-separator character just like any other
322 character: you can insert it with @kbd{C-q C-l}, and delete it with
323 @key{DEL}. Thus, you are free to paginate your file or not. However,
324 since pages are often meaningful divisions of the file, Emacs provides
325 commands to move over them and operate on them.
326
327 @table @kbd
328 @item C-x [
329 Move point to previous page boundary (@code{backward-page}).
330 @item C-x ]
331 Move point to next page boundary (@code{forward-page}).
332 @item C-x C-p
333 Put point and mark around this page (or another page) (@code{mark-page}).
334 @item C-x l
335 Count the lines in this page (@code{count-lines-page}).
336 @end table
337
338 @kindex C-x [
339 @kindex C-x ]
340 @findex forward-page
341 @findex backward-page
342 The @kbd{C-x [} (@code{backward-page}) command moves point to immediately
343 after the previous page delimiter. If point is already right after a page
344 delimiter, it skips that one and stops at the previous one. A numeric
345 argument serves as a repeat count. The @kbd{C-x ]} (@code{forward-page})
346 command moves forward past the next page delimiter.
347
348 @kindex C-x C-p
349 @findex mark-page
350 The @kbd{C-x C-p} command (@code{mark-page}) puts point at the
351 beginning of the current page and the mark at the end. The page
352 delimiter at the end is included (the mark follows it). The page
353 delimiter at the front is excluded (point follows it). In Transient
354 Mark mode, this command activates the mark.
355
356 @kbd{C-x C-p C-w} is a handy way to kill a page to move it
357 elsewhere. If you move to another page delimiter with @kbd{C-x [} and
358 @kbd{C-x ]}, then yank the killed page, all the pages will be properly
359 delimited once again. The reason @kbd{C-x C-p} includes only the
360 following page delimiter in the region is to ensure that.
361
362 A numeric argument to @kbd{C-x C-p} is used to specify which page to go
363 to, relative to the current one. Zero means the current page. One means
364 the next page, and @minus{}1 means the previous one.
365
366 @kindex C-x l
367 @findex count-lines-page
368 The @kbd{C-x l} command (@code{count-lines-page}) is good for deciding
369 where to break a page in two. It displays in the echo area the total number
370 of lines in the current page, and then divides it up into those preceding
371 the current line and those following, as in
372
373 @example
374 Page has 96 (72+25) lines
375 @end example
376
377 @noindent
378 Notice that the sum is off by one; this is correct if point is not at the
379 beginning of a line.
380
381 @vindex page-delimiter
382 The variable @code{page-delimiter} controls where pages begin. Its
383 value is a regexp that matches the beginning of a line that separates
384 pages. The normal value of this variable is @code{"^\f"}, which
385 matches a formfeed character at the beginning of a line.
386
387 @node Filling
388 @section Filling Text
389 @cindex filling text
390
391 @dfn{Filling} text means breaking it up into lines that fit a
392 specified width. Emacs does filling in two ways. In Auto Fill mode,
393 inserting text with self-inserting characters also automatically fills
394 it. There are also explicit fill commands that you can use when editing
395 text leaves it unfilled. When you edit formatted text, you can specify
396 a style of filling for each portion of the text (@pxref{Formatted
397 Text}).
398
399 @menu
400 * Auto Fill:: Auto Fill mode breaks long lines automatically.
401 * Refill:: Keeping paragraphs filled.
402 * Fill Commands:: Commands to refill paragraphs and center lines.
403 * Fill Prefix:: Filling paragraphs that are indented
404 or in a comment, etc.
405 * Adaptive Fill:: How Emacs can determine the fill prefix automatically.
406 @end menu
407
408 @node Auto Fill
409 @subsection Auto Fill Mode
410 @cindex Auto Fill mode
411 @cindex mode, Auto Fill
412 @cindex word wrap
413
414 @dfn{Auto Fill} mode is a minor mode in which lines are broken
415 automatically when they become too wide. Breaking happens only when
416 you type a @key{SPC} or @key{RET}.
417
418 @table @kbd
419 @item M-x auto-fill-mode
420 Enable or disable Auto Fill mode.
421 @item @key{SPC}
422 @itemx @key{RET}
423 In Auto Fill mode, break lines when appropriate.
424 @end table
425
426 @findex auto-fill-mode
427 @kbd{M-x auto-fill-mode} turns Auto Fill mode on if it was off, or off
428 if it was on. With a positive numeric argument it always turns Auto
429 Fill mode on, and with a negative argument always turns it off. You can
430 see when Auto Fill mode is in effect by the presence of the word
431 @samp{Fill} in the mode line, inside the parentheses. Auto Fill mode is
432 a minor mode which is enabled or disabled for each buffer individually.
433 @xref{Minor Modes}.
434
435 In Auto Fill mode, lines are broken automatically at spaces when they
436 get longer than the desired width. Line breaking and rearrangement
437 takes place only when you type @key{SPC} or @key{RET}. If you wish to
438 insert a space or newline without permitting line-breaking, type
439 @kbd{C-q @key{SPC}} or @kbd{C-q C-j} (recall that a newline is really a
440 control-J). Also, @kbd{C-o} inserts a newline without line breaking.
441
442 Auto Fill mode works well with programming-language modes, because it
443 indents new lines with @key{TAB}. If a line ending in a comment gets
444 too long, the text of the comment is split into two comment lines.
445 Optionally, new comment delimiters are inserted at the end of the first
446 line and the beginning of the second so that each line is a separate
447 comment; the variable @code{comment-multi-line} controls the choice
448 (@pxref{Comments}).
449
450 Adaptive filling (@pxref{Adaptive Fill}) works for Auto Filling as
451 well as for explicit fill commands. It takes a fill prefix
452 automatically from the second or first line of a paragraph.
453
454 Auto Fill mode does not refill entire paragraphs; it can break lines but
455 cannot merge lines. So editing in the middle of a paragraph can result in
456 a paragraph that is not correctly filled. The easiest way to make the
457 paragraph properly filled again is usually with the explicit fill commands.
458 @ifinfo
459 @xref{Fill Commands}.
460 @end ifinfo
461
462 Many users like Auto Fill mode and want to use it in all text files.
463 The section on init files says how to arrange this permanently for yourself.
464 @xref{Init File}.
465
466 @node Refill
467 @subsection Refill Mode
468 @cindex refilling text, word processor style
469 @cindex modes, Refill
470 @cindex Refill minor mode
471
472 Refill minor mode provides support for keeping paragraphs filled as
473 you type or modify them in other ways. It provides an effect similar
474 to typical word processor behavior. This works by running a
475 paragraph-filling command at suitable times.
476
477 When you are typing text, only characters which normally trigger
478 auto filling, like the space character, will trigger refilling. This
479 is to avoid making it too slow. Apart from self-inserting characters,
480 other commands which modify the text cause refilling.
481
482 The current implementation is preliminary and probably not robust.
483 We expect to improve on it.
484
485 To toggle the use of Refill mode in the current buffer, type
486 @kbd{M-x refill-mode}.
487
488 @node Fill Commands
489 @subsection Explicit Fill Commands
490
491 @table @kbd
492 @item M-q
493 Fill current paragraph (@code{fill-paragraph}).
494 @item C-x f
495 Set the fill column (@code{set-fill-column}).
496 @item M-x fill-region
497 Fill each paragraph in the region (@code{fill-region}).
498 @item M-x fill-region-as-paragraph
499 Fill the region, considering it as one paragraph.
500 @item M-s
501 Center a line.
502 @end table
503
504 @kindex M-q
505 @findex fill-paragraph
506 To refill a paragraph, use the command @kbd{M-q}
507 (@code{fill-paragraph}). This operates on the paragraph that point is
508 inside, or the one after point if point is between paragraphs.
509 Refilling works by removing all the line-breaks, then inserting new ones
510 where necessary.
511
512 @findex fill-region
513 To refill many paragraphs, use @kbd{M-x fill-region}, which
514 divides the region into paragraphs and fills each of them.
515
516 @findex fill-region-as-paragraph
517 @kbd{M-q} and @code{fill-region} use the same criteria as @kbd{M-h}
518 for finding paragraph boundaries (@pxref{Paragraphs}). For more
519 control, you can use @kbd{M-x fill-region-as-paragraph}, which refills
520 everything between point and mark. This command deletes any blank lines
521 within the region, so separate blocks of text end up combined into one
522 block.@refill
523
524 @cindex justification
525 A numeric argument to @kbd{M-q} causes it to @dfn{justify} the text as
526 well as filling it. This means that extra spaces are inserted to make
527 the right margin line up exactly at the fill column. To remove the
528 extra spaces, use @kbd{M-q} with no argument. (Likewise for
529 @code{fill-region}.) Another way to control justification, and choose
530 other styles of filling, is with the @code{justification} text property;
531 see @ref{Format Justification}.
532
533 @kindex M-s @r{(Text mode)}
534 @cindex centering
535 @findex center-line
536 The command @kbd{M-s} (@code{center-line}) centers the current line
537 within the current fill column. With an argument @var{n}, it centers
538 @var{n} lines individually and moves past them. This binding is
539 made by Text mode and is available only in that and related modes
540 (@pxref{Text Mode}).
541
542 @vindex fill-column
543 @kindex C-x f
544 @findex set-fill-column
545 The maximum line width for filling is in the variable
546 @code{fill-column}. Altering the value of @code{fill-column} makes it
547 local to the current buffer; until that time, the default value is in
548 effect. The default is initially 70. @xref{Locals}. The easiest way
549 to set @code{fill-column} is to use the command @kbd{C-x f}
550 (@code{set-fill-column}). With a numeric argument, it uses that as the
551 new fill column. With just @kbd{C-u} as argument, it sets
552 @code{fill-column} to the current horizontal position of point.
553
554 Emacs commands normally consider a period followed by two spaces or by
555 a newline as the end of a sentence; a period followed by just one space
556 indicates an abbreviation and not the end of a sentence. To preserve
557 the distinction between these two ways of using a period, the fill
558 commands do not break a line after a period followed by just one space.
559
560 @vindex sentence-end-double-space
561 If the variable @code{sentence-end-double-space} is @code{nil}, the
562 fill commands expect and leave just one space at the end of a sentence.
563 Ordinarily this variable is @code{t}, so the fill commands insist on
564 two spaces for the end of a sentence, as explained above. @xref{Sentences}.
565
566 @vindex colon-double-space
567 If the variable @code{colon-double-space} is non-@code{nil}, the
568 fill commands put two spaces after a colon.
569
570 @vindex sentence-end-without-period
571 Some languages do not use period to indicate end of sentence. For
572 example, a sentence in Thai text ends with double space but without a
573 period. Set the variable @code{sentence-end-without-period} to
574 @code{t} to tell the sentence commands that a period is not necessary.
575
576 @vindex fill-nobreak-predicate
577 The variable @code{fill-nobreak-predicate} specifies additional
578 conditions for where line-breaking is allowed. Its value is either
579 @code{nil} or a Lisp function; the function is called with no
580 arguments, and if it returns a non-@code{nil} value, then point is not
581 a good place to break the line. Two standard functions you can use are
582 @code{fill-single-word-nobreak-p} (don't break after the first word of
583 a sentence or before the last) and @code{fill-french-nobreak-p} (don't
584 break after @samp{(} or before @samp{)}, @samp{:} or @samp{?}).
585
586 @node Fill Prefix
587 @subsection The Fill Prefix
588
589 @cindex fill prefix
590 To fill a paragraph in which each line starts with a special marker
591 (which might be a few spaces, giving an indented paragraph), you can use
592 the @dfn{fill prefix} feature. The fill prefix is a string that Emacs
593 expects every line to start with, and which is not included in filling.
594 You can specify a fill prefix explicitly; Emacs can also deduce the
595 fill prefix automatically (@pxref{Adaptive Fill}).
596
597 @table @kbd
598 @item C-x .
599 Set the fill prefix (@code{set-fill-prefix}).
600 @item M-q
601 Fill a paragraph using current fill prefix (@code{fill-paragraph}).
602 @item M-x fill-individual-paragraphs
603 Fill the region, considering each change of indentation as starting a
604 new paragraph.
605 @item M-x fill-nonuniform-paragraphs
606 Fill the region, considering only paragraph-separator lines as starting
607 a new paragraph.
608 @end table
609
610 @kindex C-x .
611 @findex set-fill-prefix
612 To specify a fill prefix for the current buffer, move to a line that
613 starts with the desired prefix, put point at the end of the prefix,
614 and give the command @w{@kbd{C-x .}}@: (@code{set-fill-prefix}).
615 That's a period after the @kbd{C-x}. To turn off the fill prefix,
616 specify an empty prefix: type @w{@kbd{C-x .}}@: with point at the
617 beginning of a line.@refill
618
619 When a fill prefix is in effect, the fill commands remove the fill
620 prefix from each line before filling and insert it on each line after
621 filling. (The beginning of the first line is left unchanged, since
622 often that is intentionally different.) Auto Fill mode also inserts
623 the fill prefix automatically when it makes a new line. The @kbd{C-o}
624 command inserts the fill prefix on new lines it creates, when you use
625 it at the beginning of a line (@pxref{Blank Lines}). Conversely, the
626 command @kbd{M-^} deletes the prefix (if it occurs) after the newline
627 that it deletes (@pxref{Indentation}).
628
629 For example, if @code{fill-column} is 40 and you set the fill prefix
630 to @samp{;; }, then @kbd{M-q} in the following text
631
632 @example
633 ;; This is an
634 ;; example of a paragraph
635 ;; inside a Lisp-style comment.
636 @end example
637
638 @noindent
639 produces this:
640
641 @example
642 ;; This is an example of a paragraph
643 ;; inside a Lisp-style comment.
644 @end example
645
646 Lines that do not start with the fill prefix are considered to start
647 paragraphs, both in @kbd{M-q} and the paragraph commands; this gives
648 good results for paragraphs with hanging indentation (every line
649 indented except the first one). Lines which are blank or indented once
650 the prefix is removed also separate or start paragraphs; this is what
651 you want if you are writing multi-paragraph comments with a comment
652 delimiter on each line.
653
654 @findex fill-individual-paragraphs
655 You can use @kbd{M-x fill-individual-paragraphs} to set the fill
656 prefix for each paragraph automatically. This command divides the
657 region into paragraphs, treating every change in the amount of
658 indentation as the start of a new paragraph, and fills each of these
659 paragraphs. Thus, all the lines in one ``paragraph'' have the same
660 amount of indentation. That indentation serves as the fill prefix for
661 that paragraph.
662
663 @findex fill-nonuniform-paragraphs
664 @kbd{M-x fill-nonuniform-paragraphs} is a similar command that divides
665 the region into paragraphs in a different way. It considers only
666 paragraph-separating lines (as defined by @code{paragraph-separate}) as
667 starting a new paragraph. Since this means that the lines of one
668 paragraph may have different amounts of indentation, the fill prefix
669 used is the smallest amount of indentation of any of the lines of the
670 paragraph. This gives good results with styles that indent a paragraph's
671 first line more or less that the rest of the paragraph.
672
673 @vindex fill-prefix
674 The fill prefix is stored in the variable @code{fill-prefix}. Its value
675 is a string, or @code{nil} when there is no fill prefix. This is a
676 per-buffer variable; altering the variable affects only the current buffer,
677 but there is a default value which you can change as well. @xref{Locals}.
678
679 The @code{indentation} text property provides another way to control
680 the amount of indentation paragraphs receive. @xref{Format Indentation}.
681
682 @node Adaptive Fill
683 @subsection Adaptive Filling
684
685 @cindex adaptive filling
686 The fill commands can deduce the proper fill prefix for a paragraph
687 automatically in certain cases: either whitespace or certain punctuation
688 characters at the beginning of a line are propagated to all lines of the
689 paragraph.
690
691 If the paragraph has two or more lines, the fill prefix is taken from
692 the paragraph's second line, but only if it appears on the first line as
693 well.
694
695 If a paragraph has just one line, fill commands @emph{may} take a
696 prefix from that line. The decision is complicated because there are
697 three reasonable things to do in such a case:
698
699 @itemize @bullet
700 @item
701 Use the first line's prefix on all the lines of the paragraph.
702
703 @item
704 Indent subsequent lines with whitespace, so that they line up under the
705 text that follows the prefix on the first line, but don't actually copy
706 the prefix from the first line.
707
708 @item
709 Don't do anything special with the second and following lines.
710 @end itemize
711
712 All three of these styles of formatting are commonly used. So the
713 fill commands try to determine what you would like, based on the prefix
714 that appears and on the major mode. Here is how.
715
716 @vindex adaptive-fill-first-line-regexp
717 If the prefix found on the first line matches
718 @code{adaptive-fill-first-line-regexp}, or if it appears to be a
719 comment-starting sequence (this depends on the major mode), then the
720 prefix found is used for filling the paragraph, provided it would not
721 act as a paragraph starter on subsequent lines.
722
723 Otherwise, the prefix found is converted to an equivalent number of
724 spaces, and those spaces are used as the fill prefix for the rest of the
725 lines, provided they would not act as a paragraph starter on subsequent
726 lines.
727
728 In Text mode, and other modes where only blank lines and page
729 delimiters separate paragraphs, the prefix chosen by adaptive filling
730 never acts as a paragraph starter, so it can always be used for filling.
731
732 @vindex adaptive-fill-mode
733 @vindex adaptive-fill-regexp
734 The variable @code{adaptive-fill-regexp} determines what kinds of line
735 beginnings can serve as a fill prefix: any characters at the start of
736 the line that match this regular expression are used. If you set the
737 variable @code{adaptive-fill-mode} to @code{nil}, the fill prefix is
738 never chosen automatically.
739
740 @vindex adaptive-fill-function
741 You can specify more complex ways of choosing a fill prefix
742 automatically by setting the variable @code{adaptive-fill-function} to a
743 function. This function is called with point after the left margin of a
744 line, and it should return the appropriate fill prefix based on that
745 line. If it returns @code{nil}, that means it sees no fill prefix in
746 that line.
747
748 @node Case
749 @section Case Conversion Commands
750 @cindex case conversion
751
752 Emacs has commands for converting either a single word or any arbitrary
753 range of text to upper case or to lower case.
754
755 @table @kbd
756 @item M-l
757 Convert following word to lower case (@code{downcase-word}).
758 @item M-u
759 Convert following word to upper case (@code{upcase-word}).
760 @item M-c
761 Capitalize the following word (@code{capitalize-word}).
762 @item C-x C-l
763 Convert region to lower case (@code{downcase-region}).
764 @item C-x C-u
765 Convert region to upper case (@code{upcase-region}).
766 @end table
767
768 @kindex M-l
769 @kindex M-u
770 @kindex M-c
771 @cindex words, case conversion
772 @cindex converting text to upper or lower case
773 @cindex capitalizing words
774 @findex downcase-word
775 @findex upcase-word
776 @findex capitalize-word
777 The word conversion commands are the most useful. @kbd{M-l}
778 (@code{downcase-word}) converts the word after point to lower case, moving
779 past it. Thus, repeating @kbd{M-l} converts successive words.
780 @kbd{M-u} (@code{upcase-word}) converts to all capitals instead, while
781 @kbd{M-c} (@code{capitalize-word}) puts the first letter of the word
782 into upper case and the rest into lower case. All these commands convert
783 several words at once if given an argument. They are especially convenient
784 for converting a large amount of text from all upper case to mixed case,
785 because you can move through the text using @kbd{M-l}, @kbd{M-u} or
786 @kbd{M-c} on each word as appropriate, occasionally using @kbd{M-f} instead
787 to skip a word.
788
789 When given a negative argument, the word case conversion commands apply
790 to the appropriate number of words before point, but do not move point.
791 This is convenient when you have just typed a word in the wrong case: you
792 can give the case conversion command and continue typing.
793
794 If a word case conversion command is given in the middle of a word, it
795 applies only to the part of the word which follows point. This is just
796 like what @kbd{M-d} (@code{kill-word}) does. With a negative argument,
797 case conversion applies only to the part of the word before point.
798
799 @kindex C-x C-l
800 @kindex C-x C-u
801 @findex downcase-region
802 @findex upcase-region
803 The other case conversion commands are @kbd{C-x C-u}
804 (@code{upcase-region}) and @kbd{C-x C-l} (@code{downcase-region}), which
805 convert everything between point and mark to the specified case. Point and
806 mark do not move.
807
808 The region case conversion commands @code{upcase-region} and
809 @code{downcase-region} are normally disabled. This means that they ask
810 for confirmation if you try to use them. When you confirm, you may
811 enable the command, which means it will not ask for confirmation again.
812 @xref{Disabling}.
813
814 @node Text Mode
815 @section Text Mode
816 @cindex Text mode
817 @cindex mode, Text
818 @findex text-mode
819
820 When you edit files of text in a human language, it's more convenient
821 to use Text mode rather than Fundamental mode. To enter Text mode, type
822 @kbd{M-x text-mode}.
823
824 In Text mode, only blank lines and page delimiters separate
825 paragraphs. As a result, paragraphs can be indented, and adaptive
826 filling determines what indentation to use when filling a paragraph.
827 @xref{Adaptive Fill}.
828
829 @kindex TAB @r{(Text mode)}
830 Text mode defines @key{TAB} to run @code{indent-relative}
831 (@pxref{Indentation}), so that you can conveniently indent a line like
832 the previous line.
833
834 Text mode turns off the features concerned with comments except when
835 you explicitly invoke them. It changes the syntax table so that
836 single-quotes are considered part of words. However, if a word starts
837 with single-quotes, then these are treated as a prefix for purposes
838 such as capitalization. That is, @kbd{M-c} will convert
839 @samp{'hello'} into @samp{'Hello'}, as expected.
840
841 @cindex Paragraph-Indent Text mode
842 @cindex mode, Paragraph-Indent Text
843 @findex paragraph-indent-text-mode
844 @findex paragraph-indent-minor-mode
845 If you indent the first lines of paragraphs, then you should use
846 Paragraph-Indent Text mode rather than Text mode. In this mode, you do
847 not need to have blank lines between paragraphs, because the first-line
848 indentation is sufficient to start a paragraph; however paragraphs in
849 which every line is indented are not supported. Use @kbd{M-x
850 paragraph-indent-text-mode} to enter this mode. Use @kbd{M-x
851 paragraph-indent-minor-mode} to enter an equivalent minor mode, for
852 instance during mail composition.
853
854 @kindex M-TAB @r{(Text mode)}
855 Text mode, and all the modes based on it, define @kbd{M-@key{TAB}}
856 as the command @code{ispell-complete-word}, which performs completion
857 of the partial word in the buffer before point, using the spelling
858 dictionary as the space of possible words. @xref{Spelling}. If your
859 window manager defines @kbd{M-@key{TAB}} to switch windows, you can
860 type @kbd{@key{ESC} @key{TAB}} or @kbd{C-M-i}.
861
862 @vindex text-mode-hook
863 Entering Text mode runs the hook @code{text-mode-hook}. Other major
864 modes related to Text mode also run this hook, followed by hooks of
865 their own; this includes Paragraph-Indent Text mode, Nroff mode, @TeX{}
866 mode, Outline mode, and Mail mode. Hook functions on
867 @code{text-mode-hook} can look at the value of @code{major-mode} to see
868 which of these modes is actually being entered. @xref{Hooks}.
869
870 @ifinfo
871 Emacs provides two other modes for editing text that is to be passed
872 through a text formatter to produce fancy formatted printed output.
873 @xref{Nroff Mode}, for editing input to the formatter nroff.
874 @xref{TeX Mode}, for editing input to the formatter TeX.
875
876 Another mode is used for editing outlines. It allows you to view the
877 text at various levels of detail. You can view either the outline
878 headings alone or both headings and text; you can also hide some of the
879 headings at lower levels from view to make the high level structure more
880 visible. @xref{Outline Mode}.
881 @end ifinfo
882
883 @node Outline Mode
884 @section Outline Mode
885 @cindex Outline mode
886 @cindex mode, Outline
887 @cindex invisible lines
888
889 @findex outline-mode
890 @findex outline-minor-mode
891 @vindex outline-minor-mode-prefix
892 Outline mode is a major mode much like Text mode but intended for
893 editing outlines. It allows you to make parts of the text temporarily
894 invisible so that you can see the outline structure. Type @kbd{M-x
895 outline-mode} to switch to Outline mode as the major mode of the current
896 buffer.
897
898 When Outline mode makes a line invisible, the line does not appear
899 on the screen. The screen appears exactly as if the invisible line
900 were deleted, except that an ellipsis (three periods in a row) appears
901 at the end of the previous visible line. (Multiple consecutive
902 invisible lines produce just one ellipsis.)
903
904 Editing commands that operate on lines, such as @kbd{C-n} and
905 @kbd{C-p}, treat the text of the invisible line as part of the previous
906 visible line. Killing the ellipsis at the end of a visible line
907 really kills all the following invisible lines.
908
909 Outline minor mode provides the same commands as the major mode,
910 Outline mode, but you can use it in conjunction with other major modes.
911 Type @kbd{M-x outline-minor-mode} to enable the Outline minor mode in
912 the current buffer. You can also specify this in the text of a file,
913 with a file local variable of the form @samp{mode: outline-minor}
914 (@pxref{File Variables}).
915
916 @kindex C-c @@ @r{(Outline minor mode)}
917 The major mode, Outline mode, provides special key bindings on the
918 @kbd{C-c} prefix. Outline minor mode provides similar bindings with
919 @kbd{C-c @@} as the prefix; this is to reduce the conflicts with the
920 major mode's special commands. (The variable
921 @code{outline-minor-mode-prefix} controls the prefix used.)
922
923 @vindex outline-mode-hook
924 Entering Outline mode runs the hook @code{text-mode-hook} followed by
925 the hook @code{outline-mode-hook} (@pxref{Hooks}).
926
927 @menu
928 * Format: Outline Format. What the text of an outline looks like.
929 * Motion: Outline Motion. Special commands for moving through
930 outlines.
931 * Visibility: Outline Visibility. Commands to control what is visible.
932 * Views: Outline Views. Outlines and multiple views.
933 * Foldout:: Folding means zooming in on outlines.
934 @end menu
935
936 @node Outline Format
937 @subsection Format of Outlines
938
939 @cindex heading lines (Outline mode)
940 @cindex body lines (Outline mode)
941 Outline mode assumes that the lines in the buffer are of two types:
942 @dfn{heading lines} and @dfn{body lines}. A heading line represents a
943 topic in the outline. Heading lines start with one or more stars; the
944 number of stars determines the depth of the heading in the outline
945 structure. Thus, a heading line with one star is a major topic; all the
946 heading lines with two stars between it and the next one-star heading
947 are its subtopics; and so on. Any line that is not a heading line is a
948 body line. Body lines belong with the preceding heading line. Here is
949 an example:
950
951 @example
952 * Food
953 This is the body,
954 which says something about the topic of food.
955
956 ** Delicious Food
957 This is the body of the second-level header.
958
959 ** Distasteful Food
960 This could have
961 a body too, with
962 several lines.
963
964 *** Dormitory Food
965
966 * Shelter
967 Another first-level topic with its header line.
968 @end example
969
970 A heading line together with all following body lines is called
971 collectively an @dfn{entry}. A heading line together with all following
972 deeper heading lines and their body lines is called a @dfn{subtree}.
973
974 @vindex outline-regexp
975 You can customize the criterion for distinguishing heading lines
976 by setting the variable @code{outline-regexp}. Any line whose
977 beginning has a match for this regexp is considered a heading line.
978 Matches that start within a line (not at the left margin) do not count.
979 The length of the matching text determines the level of the heading;
980 longer matches make a more deeply nested level. Thus, for example,
981 if a text formatter has commands @samp{@@chapter}, @samp{@@section}
982 and @samp{@@subsection} to divide the document into chapters and
983 sections, you could make those lines count as heading lines by
984 setting @code{outline-regexp} to @samp{"@@chap\\|@@\\(sub\\)*section"}.
985 Note the trick: the two words @samp{chapter} and @samp{section} are equally
986 long, but by defining the regexp to match only @samp{chap} we ensure
987 that the length of the text matched on a chapter heading is shorter,
988 so that Outline mode will know that sections are contained in chapters.
989 This works as long as no other command starts with @samp{@@chap}.
990
991 @vindex outline-level
992 You can change the rule for calculating the level of a heading line
993 by setting the variable @code{outline-level}. The value of
994 @code{outline-level} should be a function that takes no arguments and
995 returns the level of the current heading. Some major modes such as C,
996 Nroff, and Emacs Lisp mode set this variable and @code{outline-regexp}
997 in order to work with Outline minor mode.
998
999 @node Outline Motion
1000 @subsection Outline Motion Commands
1001
1002 Outline mode provides special motion commands that move backward and
1003 forward to heading lines.
1004
1005 @table @kbd
1006 @item C-c C-n
1007 Move point to the next visible heading line
1008 (@code{outline-next-visible-heading}).
1009 @item C-c C-p
1010 Move point to the previous visible heading line
1011 (@code{outline-previous-visible-heading}).
1012 @item C-c C-f
1013 Move point to the next visible heading line at the same level
1014 as the one point is on (@code{outline-forward-same-level}).
1015 @item C-c C-b
1016 Move point to the previous visible heading line at the same level
1017 (@code{outline-backward-same-level}).
1018 @item C-c C-u
1019 Move point up to a lower-level (more inclusive) visible heading line
1020 (@code{outline-up-heading}).
1021 @end table
1022
1023 @findex outline-next-visible-heading
1024 @findex outline-previous-visible-heading
1025 @kindex C-c C-n @r{(Outline mode)}
1026 @kindex C-c C-p @r{(Outline mode)}
1027 @kbd{C-c C-n} (@code{outline-next-visible-heading}) moves down to the next
1028 heading line. @kbd{C-c C-p} (@code{outline-previous-visible-heading}) moves
1029 similarly backward. Both accept numeric arguments as repeat counts. The
1030 names emphasize that invisible headings are skipped, but this is not really
1031 a special feature. All editing commands that look for lines ignore the
1032 invisible lines automatically.@refill
1033
1034 @findex outline-up-heading
1035 @findex outline-forward-same-level
1036 @findex outline-backward-same-level
1037 @kindex C-c C-f @r{(Outline mode)}
1038 @kindex C-c C-b @r{(Outline mode)}
1039 @kindex C-c C-u @r{(Outline mode)}
1040 More powerful motion commands understand the level structure of headings.
1041 @kbd{C-c C-f} (@code{outline-forward-same-level}) and
1042 @kbd{C-c C-b} (@code{outline-backward-same-level}) move from one
1043 heading line to another visible heading at the same depth in
1044 the outline. @kbd{C-c C-u} (@code{outline-up-heading}) moves
1045 backward to another heading that is less deeply nested.
1046
1047 @node Outline Visibility
1048 @subsection Outline Visibility Commands
1049
1050 The other special commands of outline mode are used to make lines visible
1051 or invisible. Their names all start with @code{hide} or @code{show}.
1052 Most of them fall into pairs of opposites. They are not undoable; instead,
1053 you can undo right past them. Making lines visible or invisible is simply
1054 not recorded by the undo mechanism.
1055
1056 @table @kbd
1057 @item C-c C-t
1058 Make all body lines in the buffer invisible (@code{hide-body}).
1059 @item C-c C-a
1060 Make all lines in the buffer visible (@code{show-all}).
1061 @item C-c C-d
1062 Make everything under this heading invisible, not including this
1063 heading itself (@code{hide-subtree}).
1064 @item C-c C-s
1065 Make everything under this heading visible, including body,
1066 subheadings, and their bodies (@code{show-subtree}).
1067 @item C-c C-l
1068 Make the body of this heading line, and of all its subheadings,
1069 invisible (@code{hide-leaves}).
1070 @item C-c C-k
1071 Make all subheadings of this heading line, at all levels, visible
1072 (@code{show-branches}).
1073 @item C-c C-i
1074 Make immediate subheadings (one level down) of this heading line
1075 visible (@code{show-children}).
1076 @item C-c C-c
1077 Make this heading line's body invisible (@code{hide-entry}).
1078 @item C-c C-e
1079 Make this heading line's body visible (@code{show-entry}).
1080 @item C-c C-q
1081 Hide everything except the top @var{n} levels of heading lines
1082 (@code{hide-sublevels}).
1083 @item C-c C-o
1084 Hide everything except for the heading or body that point is in, plus
1085 the headings leading up from there to the top level of the outline
1086 (@code{hide-other}).
1087 @end table
1088
1089 @findex hide-entry
1090 @findex show-entry
1091 @kindex C-c C-c @r{(Outline mode)}
1092 @kindex C-c C-e @r{(Outline mode)}
1093 Two commands that are exact opposites are @kbd{C-c C-c}
1094 (@code{hide-entry}) and @kbd{C-c C-e} (@code{show-entry}). They are
1095 used with point on a heading line, and apply only to the body lines of
1096 that heading. Subheadings and their bodies are not affected.
1097
1098 @findex hide-subtree
1099 @findex show-subtree
1100 @kindex C-c C-s @r{(Outline mode)}
1101 @kindex C-c C-d @r{(Outline mode)}
1102 @cindex subtree (Outline mode)
1103 Two more powerful opposites are @kbd{C-c C-d} (@code{hide-subtree}) and
1104 @kbd{C-c C-s} (@code{show-subtree}). Both expect to be used when point is
1105 on a heading line, and both apply to all the lines of that heading's
1106 @dfn{subtree}: its body, all its subheadings, both direct and indirect, and
1107 all of their bodies. In other words, the subtree contains everything
1108 following this heading line, up to and not including the next heading of
1109 the same or higher rank.@refill
1110
1111 @findex hide-leaves
1112 @findex show-branches
1113 @kindex C-c C-l @r{(Outline mode)}
1114 @kindex C-c C-k @r{(Outline mode)}
1115 Intermediate between a visible subtree and an invisible one is having
1116 all the subheadings visible but none of the body. There are two
1117 commands for doing this, depending on whether you want to hide the
1118 bodies or make the subheadings visible. They are @kbd{C-c C-l}
1119 (@code{hide-leaves}) and @kbd{C-c C-k} (@code{show-branches}).
1120
1121 @kindex C-c C-i @r{(Outline mode)}
1122 @findex show-children
1123 A little weaker than @code{show-branches} is @kbd{C-c C-i}
1124 (@code{show-children}). It makes just the direct subheadings
1125 visible---those one level down. Deeper subheadings remain invisible, if
1126 they were invisible.@refill
1127
1128 @findex hide-body
1129 @findex show-all
1130 @kindex C-c C-t @r{(Outline mode)}
1131 @kindex C-c C-a @r{(Outline mode)}
1132 Two commands have a blanket effect on the whole file. @kbd{C-c C-t}
1133 (@code{hide-body}) makes all body lines invisible, so that you see just
1134 the outline structure. @kbd{C-c C-a} (@code{show-all}) makes all lines
1135 visible. These commands can be thought of as a pair of opposites even
1136 though @kbd{C-c C-a} applies to more than just body lines.
1137
1138 @findex hide-sublevels
1139 @kindex C-c C-q @r{(Outline mode)}
1140 The command @kbd{C-c C-q} (@code{hide-sublevels}) hides all but the
1141 top level headings. With a numeric argument @var{n}, it hides everything
1142 except the top @var{n} levels of heading lines.
1143
1144 @findex hide-other
1145 @kindex C-c C-o @r{(Outline mode)}
1146 The command @kbd{C-c C-o} (@code{hide-other}) hides everything except
1147 the heading and body text that point is in, plus its parents (the headers
1148 leading up from there to top level in the outline) and the top level
1149 headings.
1150
1151 @findex reveal-mode
1152 When incremental search finds text that is hidden by Outline mode,
1153 it makes that part of the buffer visible. If you exit the search
1154 at that position, the text remains visible. You can also
1155 automatically make text visible as you navigate in it by using
1156 @kbd{M-x reveal-mode}.
1157
1158 @node Outline Views
1159 @subsection Viewing One Outline in Multiple Views
1160
1161 @cindex multiple views of outline
1162 @cindex views of an outline
1163 @cindex outline with multiple views
1164 @cindex indirect buffers and outlines
1165 You can display two views of a single outline at the same time, in
1166 different windows. To do this, you must create an indirect buffer using
1167 @kbd{M-x make-indirect-buffer}. The first argument of this command is
1168 the existing outline buffer name, and its second argument is the name to
1169 use for the new indirect buffer. @xref{Indirect Buffers}.
1170
1171 Once the indirect buffer exists, you can display it in a window in the
1172 normal fashion, with @kbd{C-x 4 b} or other Emacs commands. The Outline
1173 mode commands to show and hide parts of the text operate on each buffer
1174 independently; as a result, each buffer can have its own view. If you
1175 want more than two views on the same outline, create additional indirect
1176 buffers.
1177
1178 @node Foldout
1179 @subsection Folding Editing
1180
1181 @cindex folding editing
1182 The Foldout package extends Outline mode and Outline minor mode with
1183 ``folding'' commands. The idea of folding is that you zoom in on a
1184 nested portion of the outline, while hiding its relatives at higher
1185 levels.
1186
1187 Consider an Outline mode buffer with all the text and subheadings under
1188 level-1 headings hidden. To look at what is hidden under one of these
1189 headings, you could use @kbd{C-c C-e} (@kbd{M-x show-entry}) to expose
1190 the body, or @kbd{C-c C-i} to expose the child (level-2) headings.
1191
1192 @kindex C-c C-z
1193 @findex foldout-zoom-subtree
1194 With Foldout, you use @kbd{C-c C-z} (@kbd{M-x foldout-zoom-subtree}).
1195 This exposes the body and child subheadings, and narrows the buffer so
1196 that only the @w{level-1} heading, the body and the level-2 headings are
1197 visible. Now to look under one of the level-2 headings, position the
1198 cursor on it and use @kbd{C-c C-z} again. This exposes the level-2 body
1199 and its level-3 child subheadings and narrows the buffer again. Zooming
1200 in on successive subheadings can be done as much as you like. A string
1201 in the mode line shows how deep you've gone.
1202
1203 When zooming in on a heading, to see only the child subheadings specify
1204 a numeric argument: @kbd{C-u C-c C-z}. The number of levels of children
1205 can be specified too (compare @kbd{M-x show-children}), e.g.@: @kbd{M-2
1206 C-c C-z} exposes two levels of child subheadings. Alternatively, the
1207 body can be specified with a negative argument: @kbd{M-- C-c C-z}. The
1208 whole subtree can be expanded, similarly to @kbd{C-c C-s} (@kbd{M-x
1209 show-subtree}), by specifying a zero argument: @kbd{M-0 C-c C-z}.
1210
1211 While you're zoomed in, you can still use Outline mode's exposure and
1212 hiding functions without disturbing Foldout. Also, since the buffer is
1213 narrowed, ``global'' editing actions will only affect text under the
1214 zoomed-in heading. This is useful for restricting changes to a
1215 particular chapter or section of your document.
1216
1217 @kindex C-c C-x
1218 @findex foldout-exit-fold
1219 To unzoom (exit) a fold, use @kbd{C-c C-x} (@kbd{M-x foldout-exit-fold}).
1220 This hides all the text and subheadings under the top-level heading and
1221 returns you to the previous view of the buffer. Specifying a numeric
1222 argument exits that many levels of folds. Specifying a zero argument
1223 exits all folds.
1224
1225 To cancel the narrowing of a fold without hiding the text and
1226 subheadings, specify a negative argument. For example, @kbd{M--2 C-c
1227 C-x} exits two folds and leaves the text and subheadings exposed.
1228
1229 Foldout mode also provides mouse commands for entering and exiting
1230 folds, and for showing and hiding text:
1231
1232 @table @asis
1233 @item @kbd{C-M-Mouse-1} zooms in on the heading clicked on
1234 @itemize @asis
1235 @item
1236 single click: expose body.
1237 @item
1238 double click: expose subheadings.
1239 @item
1240 triple click: expose body and subheadings.
1241 @item
1242 quad click: expose entire subtree.
1243 @end itemize
1244 @item @kbd{C-M-Mouse-2} exposes text under the heading clicked on
1245 @itemize @asis
1246 @item
1247 single click: expose body.
1248 @item
1249 double click: expose subheadings.
1250 @item
1251 triple click: expose body and subheadings.
1252 @item
1253 quad click: expose entire subtree.
1254 @end itemize
1255 @item @kbd{C-M-Mouse-3} hides text under the heading clicked on or exits fold
1256 @itemize @asis
1257 @item
1258 single click: hide subtree.
1259 @item
1260 double click: exit fold and hide text.
1261 @item
1262 triple click: exit fold without hiding text.
1263 @item
1264 quad click: exit all folds and hide text.
1265 @end itemize
1266 @end table
1267
1268 @vindex foldout-mouse-modifiers
1269 You can specify different modifier keys (instead of
1270 @kbd{Control-Meta-}) by setting @code{foldout-mouse-modifiers}; but if
1271 you have already loaded the @file{foldout.el} library, you must reload
1272 it in order for this to take effect.
1273
1274 To use the Foldout package, you can type @kbd{M-x load-library
1275 @key{RET} foldout @key{RET}}; or you can arrange for to do that
1276 automatically by putting this in your @file{.emacs} file:
1277
1278 @example
1279 (eval-after-load "outline" '(require 'foldout))
1280 @end example
1281
1282 @node TeX Mode
1283 @section @TeX{} Mode
1284 @cindex @TeX{} mode
1285 @cindex La@TeX{} mode
1286 @cindex Sli@TeX{} mode
1287 @cindex mode, @TeX{}
1288 @cindex mode, La@TeX{}
1289 @cindex mode, Sli@TeX{}
1290 @findex tex-mode
1291 @findex plain-tex-mode
1292 @findex latex-mode
1293 @findex slitex-mode
1294
1295 @TeX{} is a powerful text formatter written by Donald Knuth; it is also
1296 free, like GNU Emacs. La@TeX{} is a simplified input format for @TeX{},
1297 implemented by @TeX{} macros; it comes with @TeX{}. Sli@TeX{} is a special
1298 form of La@TeX{}.@footnote{Sli@TeX{} is obsoleted by the @samp{slides}
1299 document class in recent La@TeX{} versions.}
1300
1301 Emacs has a special @TeX{} mode for editing @TeX{} input files.
1302 It provides facilities for checking the balance of delimiters and for
1303 invoking @TeX{} on all or part of the file.
1304
1305 @vindex tex-default-mode
1306 @TeX{} mode has three variants, Plain @TeX{} mode, La@TeX{} mode, and
1307 Sli@TeX{} mode (these three distinct major modes differ only slightly).
1308 They are designed for editing the three different formats. The command
1309 @kbd{M-x tex-mode} looks at the contents of the buffer to determine
1310 whether the contents appear to be either La@TeX{} input or Sli@TeX{}
1311 input; if so, it selects the appropriate mode. If the file contents do
1312 not appear to be La@TeX{} or Sli@TeX{}, it selects Plain @TeX{} mode.
1313 If the contents are insufficient to determine this, the variable
1314 @code{tex-default-mode} controls which mode is used.
1315
1316 When @kbd{M-x tex-mode} does not guess right, you can use the commands
1317 @kbd{M-x plain-tex-mode}, @kbd{M-x latex-mode}, and @kbd{M-x
1318 slitex-mode} to select explicitly the particular variants of @TeX{}
1319 mode.
1320
1321 @menu
1322 * Editing: TeX Editing. Special commands for editing in TeX mode.
1323 * LaTeX: LaTeX Editing. Additional commands for LaTeX input files.
1324 * Printing: TeX Print. Commands for printing part of a file with TeX.
1325 * Misc: TeX Misc. Customization of TeX mode, and related features.
1326 @end menu
1327
1328 @node TeX Editing
1329 @subsection @TeX{} Editing Commands
1330
1331 Here are the special commands provided in @TeX{} mode for editing the
1332 text of the file.
1333
1334 @table @kbd
1335 @item "
1336 Insert, according to context, either @samp{``} or @samp{"} or
1337 @samp{''} (@code{tex-insert-quote}).
1338 @item C-j
1339 Insert a paragraph break (two newlines) and check the previous
1340 paragraph for unbalanced braces or dollar signs
1341 (@code{tex-terminate-paragraph}).
1342 @item M-x tex-validate-region
1343 Check each paragraph in the region for unbalanced braces or dollar signs.
1344 @item C-c @{
1345 Insert @samp{@{@}} and position point between them (@code{tex-insert-braces}).
1346 @item C-c @}
1347 Move forward past the next unmatched close brace (@code{up-list}).
1348 @end table
1349
1350 @findex tex-insert-quote
1351 @kindex " @r{(@TeX{} mode)}
1352 In @TeX{}, the character @samp{"} is not normally used; we use
1353 @samp{``} to start a quotation and @samp{''} to end one. To make
1354 editing easier under this formatting convention, @TeX{} mode overrides
1355 the normal meaning of the key @kbd{"} with a command that inserts a pair
1356 of single-quotes or backquotes (@code{tex-insert-quote}). To be
1357 precise, this command inserts @samp{``} after whitespace or an open
1358 brace, @samp{"} after a backslash, and @samp{''} after any other
1359 character.
1360
1361 If you need the character @samp{"} itself in unusual contexts, use
1362 @kbd{C-q} to insert it. Also, @kbd{"} with a numeric argument always
1363 inserts that number of @samp{"} characters. You can turn off the
1364 feature of @kbd{"} expansion by eliminating that binding in the local
1365 map (@pxref{Key Bindings}).
1366
1367 In @TeX{} mode, @samp{$} has a special syntax code which attempts to
1368 understand the way @TeX{} math mode delimiters match. When you insert a
1369 @samp{$} that is meant to exit math mode, the position of the matching
1370 @samp{$} that entered math mode is displayed for a second. This is the
1371 same feature that displays the open brace that matches a close brace that
1372 is inserted. However, there is no way to tell whether a @samp{$} enters
1373 math mode or leaves it; so when you insert a @samp{$} that enters math
1374 mode, the previous @samp{$} position is shown as if it were a match, even
1375 though they are actually unrelated.
1376
1377 @findex tex-insert-braces
1378 @kindex C-c @{ @r{(@TeX{} mode)}
1379 @findex up-list
1380 @kindex C-c @} @r{(@TeX{} mode)}
1381 @TeX{} uses braces as delimiters that must match. Some users prefer
1382 to keep braces balanced at all times, rather than inserting them
1383 singly. Use @kbd{C-c @{} (@code{tex-insert-braces}) to insert a pair of
1384 braces. It leaves point between the two braces so you can insert the
1385 text that belongs inside. Afterward, use the command @kbd{C-c @}}
1386 (@code{up-list}) to move forward past the close brace.
1387
1388 @findex tex-validate-region
1389 @findex tex-terminate-paragraph
1390 @kindex C-j @r{(@TeX{} mode)}
1391 There are two commands for checking the matching of braces. @kbd{C-j}
1392 (@code{tex-terminate-paragraph}) checks the paragraph before point, and
1393 inserts two newlines to start a new paragraph. It outputs a message in
1394 the echo area if any mismatch is found. @kbd{M-x tex-validate-region}
1395 checks a region, paragraph by paragraph. The errors are listed in the
1396 @samp{*Occur*} buffer, and you can use @kbd{C-c C-c} or @kbd{Mouse-2} in
1397 that buffer to go to a particular mismatch.
1398
1399 Note that Emacs commands count square brackets and parentheses in
1400 @TeX{} mode, not just braces. This is not strictly correct for the
1401 purpose of checking @TeX{} syntax. However, parentheses and square
1402 brackets are likely to be used in text as matching delimiters and it is
1403 useful for the various motion commands and automatic match display to
1404 work with them.
1405
1406 @node LaTeX Editing
1407 @subsection La@TeX{} Editing Commands
1408
1409 La@TeX{} mode, and its variant, Sli@TeX{} mode, provide a few extra
1410 features not applicable to plain @TeX{}.
1411
1412 @table @kbd
1413 @item C-c C-o
1414 Insert @samp{\begin} and @samp{\end} for La@TeX{} block and position
1415 point on a line between them (@code{tex-latex-block}).
1416 @item C-c C-e
1417 Close the innermost La@TeX{} block not yet closed
1418 (@code{tex-close-latex-block}).
1419 @end table
1420
1421 @findex tex-latex-block
1422 @kindex C-c C-o @r{(La@TeX{} mode)}
1423 @vindex latex-block-names
1424 In La@TeX{} input, @samp{\begin} and @samp{\end} commands are used to
1425 group blocks of text. To insert a @samp{\begin} and a matching
1426 @samp{\end} (on a new line following the @samp{\begin}), use @kbd{C-c
1427 C-o} (@code{tex-latex-block}). A blank line is inserted between the
1428 two, and point is left there. You can use completion when you enter the
1429 block type; to specify additional block type names beyond the standard
1430 list, set the variable @code{latex-block-names}. For example, here's
1431 how to add @samp{theorem}, @samp{corollary}, and @samp{proof}:
1432
1433 @example
1434 (setq latex-block-names '("theorem" "corollary" "proof"))
1435 @end example
1436
1437 @findex tex-close-latex-block
1438 @kindex C-c C-e @r{(La@TeX{} mode)}
1439 In La@TeX{} input, @samp{\begin} and @samp{\end} commands must
1440 balance. You can use @kbd{C-c C-e} (@code{tex-close-latex-block}) to
1441 insert automatically a matching @samp{\end} to match the last unmatched
1442 @samp{\begin}. It indents the @samp{\end} to match the corresponding
1443 @samp{\begin}. It inserts a newline after @samp{\end} if point is at
1444 the beginning of a line.
1445
1446 @node TeX Print
1447 @subsection @TeX{} Printing Commands
1448
1449 You can invoke @TeX{} as an inferior of Emacs on either the entire
1450 contents of the buffer or just a region at a time. Running @TeX{} in
1451 this way on just one chapter is a good way to see what your changes
1452 look like without taking the time to format the entire file.
1453
1454 @table @kbd
1455 @item C-c C-r
1456 Invoke @TeX{} on the current region, together with the buffer's header
1457 (@code{tex-region}).
1458 @item C-c C-b
1459 Invoke @TeX{} on the entire current buffer (@code{tex-buffer}).
1460 @item C-c @key{TAB}
1461 Invoke Bib@TeX{} on the current file (@code{tex-bibtex-file}).
1462 @item C-c C-f
1463 Invoke @TeX{} on the current file (@code{tex-file}).
1464 @item C-c C-l
1465 Recenter the window showing output from the inferior @TeX{} so that
1466 the last line can be seen (@code{tex-recenter-output-buffer}).
1467 @item C-c C-k
1468 Kill the @TeX{} subprocess (@code{tex-kill-job}).
1469 @item C-c C-p
1470 Print the output from the last @kbd{C-c C-r}, @kbd{C-c C-b}, or @kbd{C-c
1471 C-f} command (@code{tex-print}).
1472 @item C-c C-v
1473 Preview the output from the last @kbd{C-c C-r}, @kbd{C-c C-b}, or @kbd{C-c
1474 C-f} command (@code{tex-view}).
1475 @item C-c C-q
1476 Show the printer queue (@code{tex-show-print-queue}).
1477 @end table
1478
1479 @findex tex-buffer
1480 @kindex C-c C-b @r{(@TeX{} mode)}
1481 @findex tex-print
1482 @kindex C-c C-p @r{(@TeX{} mode)}
1483 @findex tex-view
1484 @kindex C-c C-v @r{(@TeX{} mode)}
1485 @findex tex-show-print-queue
1486 @kindex C-c C-q @r{(@TeX{} mode)}
1487 You can pass the current buffer through an inferior @TeX{} by means of
1488 @kbd{C-c C-b} (@code{tex-buffer}). The formatted output appears in a
1489 temporary file; to print it, type @kbd{C-c C-p} (@code{tex-print}).
1490 Afterward, you can use @kbd{C-c C-q} (@code{tex-show-print-queue}) to
1491 view the progress of your output towards being printed. If your terminal
1492 has the ability to display @TeX{} output files, you can preview the
1493 output on the terminal with @kbd{C-c C-v} (@code{tex-view}).
1494
1495 @cindex @env{TEXINPUTS} environment variable
1496 @vindex tex-directory
1497 You can specify the directory to use for running @TeX{} by setting the
1498 variable @code{tex-directory}. @code{"."} is the default value. If
1499 your environment variable @env{TEXINPUTS} contains relative directory
1500 names, or if your files contains @samp{\input} commands with relative
1501 file names, then @code{tex-directory} @emph{must} be @code{"."} or you
1502 will get the wrong results. Otherwise, it is safe to specify some other
1503 directory, such as @code{"/tmp"}.
1504
1505 @vindex tex-run-command
1506 @vindex latex-run-command
1507 @vindex slitex-run-command
1508 @vindex tex-dvi-print-command
1509 @vindex tex-dvi-view-command
1510 @vindex tex-show-queue-command
1511 If you want to specify which shell commands are used in the inferior @TeX{},
1512 you can do so by setting the values of the variables @code{tex-run-command},
1513 @code{latex-run-command}, @code{slitex-run-command},
1514 @code{tex-dvi-print-command}, @code{tex-dvi-view-command}, and
1515 @code{tex-show-queue-command}. You @emph{must} set the value of
1516 @code{tex-dvi-view-command} for your particular terminal; this variable
1517 has no default value. The other variables have default values that may
1518 (or may not) be appropriate for your system.
1519
1520 Normally, the file name given to these commands comes at the end of
1521 the command string; for example, @samp{latex @var{filename}}. In some
1522 cases, however, the file name needs to be embedded in the command; an
1523 example is when you need to provide the file name as an argument to one
1524 command whose output is piped to another. You can specify where to put
1525 the file name with @samp{*} in the command string. For example,
1526
1527 @example
1528 (setq tex-dvi-print-command "dvips -f * | lpr")
1529 @end example
1530
1531 @findex tex-kill-job
1532 @kindex C-c C-k @r{(@TeX{} mode)}
1533 @findex tex-recenter-output-buffer
1534 @kindex C-c C-l @r{(@TeX{} mode)}
1535 The terminal output from @TeX{}, including any error messages, appears
1536 in a buffer called @samp{*tex-shell*}. If @TeX{} gets an error, you can
1537 switch to this buffer and feed it input (this works as in Shell mode;
1538 @pxref{Interactive Shell}). Without switching to this buffer you can
1539 scroll it so that its last line is visible by typing @kbd{C-c
1540 C-l}.
1541
1542 Type @kbd{C-c C-k} (@code{tex-kill-job}) to kill the @TeX{} process if
1543 you see that its output is no longer useful. Using @kbd{C-c C-b} or
1544 @kbd{C-c C-r} also kills any @TeX{} process still running.@refill
1545
1546 @findex tex-region
1547 @kindex C-c C-r @r{(@TeX{} mode)}
1548 You can also pass an arbitrary region through an inferior @TeX{} by typing
1549 @kbd{C-c C-r} (@code{tex-region}). This is tricky, however, because most files
1550 of @TeX{} input contain commands at the beginning to set parameters and
1551 define macros, without which no later part of the file will format
1552 correctly. To solve this problem, @kbd{C-c C-r} allows you to designate a
1553 part of the file as containing essential commands; it is included before
1554 the specified region as part of the input to @TeX{}. The designated part
1555 of the file is called the @dfn{header}.
1556
1557 @cindex header (@TeX{} mode)
1558 To indicate the bounds of the header in Plain @TeX{} mode, you insert two
1559 special strings in the file. Insert @samp{%**start of header} before the
1560 header, and @samp{%**end of header} after it. Each string must appear
1561 entirely on one line, but there may be other text on the line before or
1562 after. The lines containing the two strings are included in the header.
1563 If @samp{%**start of header} does not appear within the first 100 lines of
1564 the buffer, @kbd{C-c C-r} assumes that there is no header.
1565
1566 In La@TeX{} mode, the header begins with @samp{\documentclass} or
1567 @samp{\documentstyle} and ends with @samp{\begin@{document@}}. These
1568 are commands that La@TeX{} requires you to use in any case, so nothing
1569 special needs to be done to identify the header.
1570
1571 @findex tex-file
1572 @kindex C-c C-f @r{(@TeX{} mode)}
1573 The commands (@code{tex-buffer}) and (@code{tex-region}) do all of their
1574 work in a temporary directory, and do not have available any of the auxiliary
1575 files needed by @TeX{} for cross-references; these commands are generally
1576 not suitable for running the final copy in which all of the cross-references
1577 need to be correct.
1578
1579 When you want the auxiliary files for cross references, use @kbd{C-c
1580 C-f} (@code{tex-file}) which runs @TeX{} on the current buffer's file,
1581 in that file's directory. Before running @TeX{}, it offers to save any
1582 modified buffers. Generally, you need to use (@code{tex-file}) twice to
1583 get the cross-references right.
1584
1585 @vindex tex-start-options
1586 The value of the variable @code{tex-start-options} specifies
1587 options for the @TeX{} run.
1588
1589 @vindex tex-start-commands
1590 The value of the variable @code{tex-start-commands} specifies @TeX{}
1591 commands for starting @TeX{}. The default value causes @TeX{} to run
1592 in nonstop mode. To run @TeX{} interactively, set the variable to
1593 @code{""}.
1594
1595 @vindex tex-main-file
1596 Large @TeX{} documents are often split into several files---one main
1597 file, plus subfiles. Running @TeX{} on a subfile typically does not
1598 work; you have to run it on the main file. In order to make
1599 @code{tex-file} useful when you are editing a subfile, you can set the
1600 variable @code{tex-main-file} to the name of the main file. Then
1601 @code{tex-file} runs @TeX{} on that file.
1602
1603 The most convenient way to use @code{tex-main-file} is to specify it
1604 in a local variable list in each of the subfiles. @xref{File
1605 Variables}.
1606
1607 @findex tex-bibtex-file
1608 @kindex C-c TAB @r{(@TeX{} mode)}
1609 @vindex tex-bibtex-command
1610 For La@TeX{} files, you can use Bib@TeX{} to process the auxiliary
1611 file for the current buffer's file. Bib@TeX{} looks up bibliographic
1612 citations in a data base and prepares the cited references for the
1613 bibliography section. The command @kbd{C-c TAB}
1614 (@code{tex-bibtex-file}) runs the shell command
1615 (@code{tex-bibtex-command}) to produce a @samp{.bbl} file for the
1616 current buffer's file. Generally, you need to do @kbd{C-c C-f}
1617 (@code{tex-file}) once to generate the @samp{.aux} file, then do
1618 @kbd{C-c TAB} (@code{tex-bibtex-file}), and then repeat @kbd{C-c C-f}
1619 (@code{tex-file}) twice more to get the cross-references correct.
1620
1621 @node TeX Misc
1622 @subsection @TeX{} Mode Miscellany
1623
1624 @vindex tex-shell-hook
1625 @vindex tex-mode-hook
1626 @vindex latex-mode-hook
1627 @vindex slitex-mode-hook
1628 @vindex plain-tex-mode-hook
1629 Entering any variant of @TeX{} mode runs the hooks
1630 @code{text-mode-hook} and @code{tex-mode-hook}. Then it runs either
1631 @code{plain-tex-mode-hook}, @code{latex-mode-hook}, or
1632 @code{slitex-mode-hook}, whichever is appropriate. Starting the
1633 @TeX{} shell runs the hook @code{tex-shell-hook}. @xref{Hooks}.
1634
1635 @findex iso-iso2tex
1636 @findex iso-tex2iso
1637 @findex iso-iso2gtex
1638 @findex iso-gtex2iso
1639 @cindex Latin-1 @TeX{} encoding
1640 @cindex @TeX{} encoding
1641 The commands @kbd{M-x iso-iso2tex}, @kbd{M-x iso-tex2iso}, @kbd{M-x
1642 iso-iso2gtex} and @kbd{M-x iso-gtex2iso} can be used to convert
1643 between Latin-1 encoded files and @TeX{}-encoded equivalents.
1644 @ignore
1645 @c Too cryptic to be useful, too cryptic for me to make it better -- rms.
1646 They
1647 are included by default in the @code{format-alist} variable, so they
1648 can be used with @kbd{M-x format-find-file}, for instance.
1649 @end ignore
1650
1651 @ignore @c Not worth documenting if it is only for Czech -- rms.
1652 @findex tildify-buffer
1653 @findex tildify-region
1654 @cindex ties, @TeX{}, inserting
1655 @cindex hard spaces, @TeX{}, inserting
1656 The commands @kbd{M-x tildify-buffer} and @kbd{M-x tildify-region}
1657 insert @samp{~} (@dfn{tie}) characters where they are conventionally
1658 required. This is set up for Czech---customize the group
1659 @samp{tildify} for other languages or for other sorts of markup.
1660 @end ignore
1661
1662 @cindex Ref@TeX{} package
1663 @cindex references, La@TeX{}
1664 @cindex La@TeX{} references
1665 For managing all kinds of references for La@TeX{}, you can use
1666 Ref@TeX{}. @inforef{Top,, reftex}.
1667
1668 @node HTML Mode
1669 @section SGML, XML, and HTML Modes
1670
1671 The major modes for SGML and HTML include indentation support and
1672 commands to operate on tags. This section describes the special
1673 commands of these modes. (HTML mode is a slightly customized variant
1674 of SGML mode.)
1675
1676 @table @kbd
1677 @item C-c C-n
1678 @kindex C-c C-n @r{(SGML mode)}
1679 @findex sgml-name-char
1680 Interactively specify a special character and insert the SGML
1681 @samp{&}-command for that character.
1682
1683 @item C-c C-t
1684 @kindex C-c C-t @r{(SGML mode)}
1685 @findex sgml-tag
1686 Interactively specify a tag and its attributes (@code{sgml-tag}).
1687 This command asks you for a tag name and for the attribute values,
1688 then inserts both the opening tag and the closing tag, leaving point
1689 between them.
1690
1691 With a prefix argument @var{n}, the command puts the tag around the
1692 @var{n} words already present in the buffer after point. With
1693 @minus{}1 as argument, it puts the tag around the region. (In
1694 Transient Mark mode, it does this whenever a region is active.)
1695
1696 @item C-c C-a
1697 @kindex C-c C-a @r{(SGML mode)}
1698 @findex sgml-attributes
1699 Interactively insert attribute values for the current tag
1700 (@code{sgml-attributes}).
1701
1702 @item C-c C-f
1703 @kindex C-c C-f @r{(SGML mode)}
1704 @findex sgml-skip-tag-forward
1705 Skip across a balanced tag group (which extends from an opening tag
1706 through its corresponding closing tag) (@code{sgml-skip-tag-forward}).
1707 A numeric argument acts as a repeat count.
1708
1709 @item C-c C-b
1710 @kindex C-c C-b @r{(SGML mode)}
1711 @findex sgml-skip-tag-backward
1712 Skip backward across a balanced tag group (which extends from an
1713 opening tag through its corresponding closing tag)
1714 (@code{sgml-skip-tag-forward}). A numeric argument acts as a repeat
1715 count.
1716
1717 @item C-c C-d
1718 @kindex C-c C-d @r{(SGML mode)}
1719 @findex sgml-delete-tag
1720 Delete the tag at or after point, and delete the matching tag too
1721 (@code{sgml-delete-tag}). If the tag at or after point is an opening
1722 tag, delete the closing tag too; if it is a closing tag, delete the
1723 opening tag too.
1724
1725 @item C-c ? @var{tag} @key{RET}
1726 @kindex C-c ? @r{(SGML mode)}
1727 @findex sgml-tag-help
1728 Display a description of the meaning of tag @var{tag}
1729 (@code{sgml-tag-help}). If the argument @var{tag} is empty, describe
1730 the tag at point.
1731
1732 @item C-c /
1733 @kindex C-c / @r{(SGML mode)}
1734 @findex sgml-close-tag
1735 Insert a close tag for the innermost unterminated tag
1736 (@code{sgml-close-tag}). If called from within a tag or a comment,
1737 close this element instead of inserting a close tag.
1738
1739 @item C-c 8
1740 @kindex C-c 8 @r{(SGML mode)}
1741 @findex sgml-name-8bit-mode
1742 Toggle a minor mode in which Latin-1 characters insert the
1743 corresponding SGML commands that stand for them, instead of the
1744 characters themselves (@code{sgml-name-8bit-mode}).
1745
1746 @item C-c C-v
1747 @kindex C-c C-v @r{(SGML mode)}
1748 @findex sgml-validate
1749 Run a shell command (which you must specify) to validate the current
1750 buffer as SGML (@code{sgml-validate}).
1751
1752 @item C-x TAB
1753 @kindex C-c TAB @r{(SGML mode)}
1754 @findex sgml-tags-invisible
1755 Toggle the visibility of existing tags in the buffer. This can be
1756 used as a cheap preview.
1757 @end table
1758
1759 @vindex sgml-xml-mode
1760 SGML mode and HTML mode support XML also. In XML, every opening tag
1761 must have an explicit closing tag. When @code{sgml-xml-mode} is
1762 non-@code{nil}, SGML mode (and HTML mode) always insert explicit
1763 closing tags. When you visit a file, these modes determine from the
1764 file contents whether it is XML or not, and set @code{sgml-xml-mode}
1765 accordingly, so that they do the right thing for the file in either
1766 case.
1767
1768 @node Nroff Mode
1769 @section Nroff Mode
1770
1771 @cindex nroff
1772 @findex nroff-mode
1773 Nroff mode is a mode like Text mode but modified to handle nroff commands
1774 present in the text. Invoke @kbd{M-x nroff-mode} to enter this mode. It
1775 differs from Text mode in only a few ways. All nroff command lines are
1776 considered paragraph separators, so that filling will never garble the
1777 nroff commands. Pages are separated by @samp{.bp} commands. Comments
1778 start with backslash-doublequote. Also, three special commands are
1779 provided that are not in Text mode:
1780
1781 @findex forward-text-line
1782 @findex backward-text-line
1783 @findex count-text-lines
1784 @kindex M-n @r{(Nroff mode)}
1785 @kindex M-p @r{(Nroff mode)}
1786 @kindex M-? @r{(Nroff mode)}
1787 @table @kbd
1788 @item M-n
1789 Move to the beginning of the next line that isn't an nroff command
1790 (@code{forward-text-line}). An argument is a repeat count.
1791 @item M-p
1792 Like @kbd{M-n} but move up (@code{backward-text-line}).
1793 @item M-?
1794 Displays in the echo area the number of text lines (lines that are not
1795 nroff commands) in the region (@code{count-text-lines}).
1796 @end table
1797
1798 @findex electric-nroff-mode
1799 The other feature of Nroff mode is that you can turn on Electric Nroff
1800 mode. This is a minor mode that you can turn on or off with @kbd{M-x
1801 electric-nroff-mode} (@pxref{Minor Modes}). When the mode is on, each
1802 time you use @key{RET} to end a line that contains an nroff command that
1803 opens a kind of grouping, the matching nroff command to close that
1804 grouping is automatically inserted on the following line. For example,
1805 if you are at the beginning of a line and type @kbd{.@: ( b @key{RET}},
1806 this inserts the matching command @samp{.)b} on a new line following
1807 point.
1808
1809 If you use Outline minor mode with Nroff mode (@pxref{Outline Mode}),
1810 heading lines are lines of the form @samp{.H} followed by a number (the
1811 header level).
1812
1813 @vindex nroff-mode-hook
1814 Entering Nroff mode runs the hook @code{text-mode-hook}, followed by
1815 the hook @code{nroff-mode-hook} (@pxref{Hooks}).
1816
1817 @node Formatted Text
1818 @section Editing Formatted Text
1819
1820 @cindex Enriched mode
1821 @cindex mode, Enriched
1822 @cindex formatted text
1823 @cindex WYSIWYG
1824 @cindex word processing
1825 @dfn{Enriched mode} is a minor mode for editing files that contain
1826 formatted text in WYSIWYG fashion, as in a word processor. Currently,
1827 formatted text in Enriched mode can specify fonts, colors, underlining,
1828 margins, and types of filling and justification. In the future, we plan
1829 to implement other formatting features as well.
1830
1831 Enriched mode is a minor mode (@pxref{Minor Modes}). It is
1832 typically used in conjunction with Text mode (@pxref{Text Mode}), but
1833 you can also use it with other major modes such as Outline mode and
1834 Paragraph-Indent Text mode.
1835
1836 @cindex text/enriched MIME format
1837 Potentially, Emacs can store formatted text files in various file
1838 formats. Currently, only one format is implemented: @dfn{text/enriched}
1839 format, which is defined by the MIME protocol. @xref{Format
1840 Conversion,, Format Conversion, elisp, the Emacs Lisp Reference Manual},
1841 for details of how Emacs recognizes and converts file formats.
1842
1843 The Emacs distribution contains a formatted text file that can serve as
1844 an example. Its name is @file{etc/enriched.doc}. It contains samples
1845 illustrating all the features described in this section. It also
1846 contains a list of ideas for future enhancements.
1847
1848 @menu
1849 * Requesting Formatted Text:: Entering and exiting Enriched mode.
1850 * Hard and Soft Newlines:: There are two different kinds of newlines.
1851 * Editing Format Info:: How to edit text properties.
1852 * Faces: Format Faces. Bold, italic, underline, etc.
1853 * Color: Format Colors. Changing the color of text.
1854 * Indent: Format Indentation. Changing the left and right margins.
1855 * Justification: Format Justification.
1856 Centering, setting text flush with the
1857 left or right margin, etc.
1858 * Other: Format Properties. The "special" text properties submenu.
1859 * Forcing Enriched Mode:: How to force use of Enriched mode.
1860 @end menu
1861
1862 @node Requesting Formatted Text
1863 @subsection Requesting to Edit Formatted Text
1864
1865 Whenever you visit a file that Emacs saved in the text/enriched
1866 format, Emacs automatically converts the formatting information in the
1867 file into Emacs's own internal format (known as @dfn{text
1868 properties}), and turns on Enriched mode.
1869
1870 @findex enriched-mode
1871 To create a new file of formatted text, first visit the nonexistent
1872 file, then type @kbd{M-x enriched-mode} before you start inserting text.
1873 This command turns on Enriched mode. Do this before you begin inserting
1874 text, to ensure that the text you insert is handled properly.
1875
1876 More generally, the command @code{enriched-mode} turns Enriched mode
1877 on if it was off, and off if it was on. With a prefix argument, this
1878 command turns Enriched mode on if the argument is positive, and turns
1879 the mode off otherwise.
1880
1881 When you save a buffer while Enriched mode is enabled in it, Emacs
1882 automatically converts the text to text/enriched format while writing it
1883 into the file. When you visit the file again, Emacs will automatically
1884 recognize the format, reconvert the text, and turn on Enriched mode
1885 again.
1886
1887 @vindex enriched-translations
1888 You can add annotations for saving additional text properties, which
1889 Emacs normally does not save, by adding to @code{enriched-translations}.
1890 Note that the text/enriched standard requires any non-standard
1891 annotations to have names starting with @samp{x-}, as in
1892 @samp{x-read-only}. This ensures that they will not conflict with
1893 standard annotations that may be added later.
1894
1895 @xref{Text Properties,,, elisp, the Emacs Lisp Reference Manual},
1896 for more information about text properties.
1897
1898 @node Hard and Soft Newlines
1899 @subsection Hard and Soft Newlines
1900 @cindex hard newline
1901 @cindex soft newline
1902 @cindex newlines, hard and soft
1903
1904 @cindex use-hard-newlines
1905 In formatted text, Emacs distinguishes between two different kinds of
1906 newlines, @dfn{hard} newlines and @dfn{soft} newlines. (You can enable
1907 or disable this feature separately in any buffer with the command
1908 @code{use-hard-newlines}.)
1909
1910 Hard newlines are used to separate paragraphs, or items in a list, or
1911 anywhere that there should always be a line break regardless of the
1912 margins. The @key{RET} command (@code{newline}) and @kbd{C-o}
1913 (@code{open-line}) insert hard newlines.
1914
1915 Soft newlines are used to make text fit between the margins. All the
1916 fill commands, including Auto Fill, insert soft newlines---and they
1917 delete only soft newlines.
1918
1919 Although hard and soft newlines look the same, it is important to bear
1920 the difference in mind. Do not use @key{RET} to break lines in the
1921 middle of filled paragraphs, or else you will get hard newlines that are
1922 barriers to further filling. Instead, let Auto Fill mode break lines,
1923 so that if the text or the margins change, Emacs can refill the lines
1924 properly. @xref{Auto Fill}.
1925
1926 On the other hand, in tables and lists, where the lines should always
1927 remain as you type them, you can use @key{RET} to end lines. For these
1928 lines, you may also want to set the justification style to
1929 @code{unfilled}. @xref{Format Justification}.
1930
1931 @node Editing Format Info
1932 @subsection Editing Format Information
1933
1934 There are two ways to alter the formatting information for a formatted
1935 text file: with keyboard commands, and with the mouse.
1936
1937 The easiest way to add properties to your document is with the Text
1938 Properties menu. You can get to this menu in two ways: from the Edit
1939 menu in the menu bar (use @kbd{@key{F10} e t} if you have no mouse),
1940 or with @kbd{C-Mouse-2} (hold the @key{CTRL} key and press the middle
1941 mouse button). There are also keyboard commands described in the
1942 following section.
1943
1944 Most of the items in the Text Properties menu lead to other submenus.
1945 These are described in the sections that follow. Some items run
1946 commands directly:
1947
1948 @table @code
1949 @findex facemenu-remove-face-props
1950 @item Remove Face Properties
1951 Delete from the region all face and color text properties
1952 (@code{facemenu-remove-face-props}).
1953
1954 @findex facemenu-remove-all
1955 @item Remove Text Properties
1956 Delete @emph{all} text properties from the region
1957 (@code{facemenu-remove-all}).
1958
1959 @findex describe-text-properties
1960 @cindex text properties of characters
1961 @cindex overlays at character position
1962 @cindex widgets at buffer position
1963 @cindex buttons at buffer position
1964 @item Describe Properties
1965 List all the text properties, widgets, buttons, and overlays of the
1966 character following point (@code{describe-text-properties}).
1967
1968 @item Display Faces
1969 Display a list of all the defined faces (@code{list-faces-display}).
1970
1971 @item Display Colors
1972 Display a list of all the defined colors (@code{list-colors-display}).
1973 @end table
1974
1975 @node Format Faces
1976 @subsection Faces in Formatted Text
1977
1978 The Faces submenu lists various Emacs faces including @code{bold},
1979 @code{italic}, and @code{underline}. Selecting one of these adds the
1980 chosen face to the region. @xref{Faces}. You can also specify a face
1981 with these keyboard commands:
1982
1983 @table @kbd
1984 @kindex M-g d @r{(Enriched mode)}
1985 @findex facemenu-set-default
1986 @item M-g d
1987 Set the region, or the next inserted character, to the @code{default} face
1988 (@code{facemenu-set-default}).
1989 @kindex M-g b @r{(Enriched mode)}
1990 @findex facemenu-set-bold
1991 @item M-g b
1992 Set the region, or the next inserted character, to the @code{bold} face
1993 (@code{facemenu-set-bold}).
1994 @kindex M-g i @r{(Enriched mode)}
1995 @findex facemenu-set-italic
1996 @item M-g i
1997 Set the region, or the next inserted character, to the @code{italic} face
1998 (@code{facemenu-set-italic}).
1999 @kindex M-g l @r{(Enriched mode)}
2000 @findex facemenu-set-bold-italic
2001 @item M-g l
2002 Set the region, or the next inserted character, to the @code{bold-italic} face
2003 (@code{facemenu-set-bold-italic}).
2004 @kindex M-g u @r{(Enriched mode)}
2005 @findex facemenu-set-underline
2006 @item M-g u
2007 Set the region, or the next inserted character, to the @code{underline} face
2008 (@code{facemenu-set-underline}).
2009 @kindex M-g o @r{(Enriched mode)}
2010 @findex facemenu-set-face
2011 @item M-g o @var{face} @key{RET}
2012 Set the region, or the next inserted character, to the face @var{face}
2013 (@code{facemenu-set-face}).
2014 @end table
2015
2016 If you use these commands with a prefix argument---or, in Transient Mark
2017 mode, if the region is not active---then these commands specify a face
2018 to use for any immediately following self-inserting input.
2019 @xref{Transient Mark}. This applies to both the keyboard commands and
2020 the menu commands.
2021
2022 Specifying the @code{default} face also resets foreground and
2023 background color to their defaults.(@pxref{Format Colors}).
2024
2025 Any self-inserting character you type inherits, by default, the face
2026 properties (as well as most other text properties) of the preceding
2027 character. Specifying any face property, including foreground or
2028 background color, for your next self-inserting character will prevent
2029 it from inheriting any face properties from the preceding character,
2030 although it will still inherit other text properties. Characters
2031 inserted by yanking do not inherit text properties.
2032
2033 Enriched mode defines two additional faces: @code{excerpt} and
2034 @code{fixed}. These correspond to codes used in the text/enriched file
2035 format.
2036
2037 The @code{excerpt} face is intended for quotations. This face is the
2038 same as @code{italic} unless you customize it (@pxref{Face Customization}).
2039
2040 The @code{fixed} face means, ``Use a fixed-width font for this part
2041 of the text.'' Applying the @code{fixed} face to a part of the text
2042 will cause that part of the text to appear in a fixed-width font, even
2043 if the default font is variable-width. This applies to Emacs and to
2044 other systems that display text/enriched format. So if you
2045 specifically want a certain part of the text to use a fixed-width
2046 font, you should specify the @code{fixed} face for that part.
2047
2048 By default, the @code{fixed} face looks the same as @code{bold}.
2049 This is an attempt to distinguish it from @code{default}. You may
2050 wish to customize @code{fixed} to some other fixed-width medium font.
2051 @xref{Face Customization}.
2052
2053 If your terminal cannot display different faces, you will not be
2054 able to see them, but you can still edit documents containing faces,
2055 and even add faces and colors to documents. The faces you specify
2056 will be visible when the file is viewed on a terminal that can display
2057 them.
2058
2059 @node Format Colors
2060 @subsection Colors in Formatted Text
2061
2062 You can specify foreground and background colors for portions of the
2063 text. There is a menu for specifying the foreground color and a menu
2064 for specifying the background color. Each color menu lists all the
2065 colors that you have used in Enriched mode in the current Emacs session.
2066
2067 If you specify a color with a prefix argument---or, in Transient
2068 Mark mode, if the region is not active---then it applies to any
2069 immediately following self-inserting input. @xref{Transient Mark}.
2070 Otherwise, the command applies to the region.
2071
2072 Each color menu contains one additional item: @samp{Other}. You can use
2073 this item to specify a color that is not listed in the menu; it reads
2074 the color name with the minibuffer. To display a list of available colors
2075 and their names, use the @samp{Display Colors} menu item in the Text
2076 Properties menu (@pxref{Editing Format Info}).
2077
2078 Any color that you specify in this way, or that is mentioned in a
2079 formatted text file that you read in, is added to the corresponding
2080 color menu for the duration of the Emacs session.
2081
2082 @findex facemenu-set-foreground
2083 @findex facemenu-set-background
2084 There are no key bindings for specifying colors, but you can do so
2085 with the extended commands @kbd{M-x facemenu-set-foreground} and
2086 @kbd{M-x facemenu-set-background}. Both of these commands read the name
2087 of the color with the minibuffer.
2088
2089 @node Format Indentation
2090 @subsection Indentation in Formatted Text
2091
2092 When editing formatted text, you can specify different amounts of
2093 indentation for the right or left margin of an entire paragraph or a
2094 part of a paragraph. The margins you specify automatically affect the
2095 Emacs fill commands (@pxref{Filling}) and line-breaking commands.
2096
2097 The Indentation submenu provides a convenient interface for specifying
2098 these properties. The submenu contains four items:
2099
2100 @table @code
2101 @kindex C-x TAB @r{(Enriched mode)}
2102 @findex increase-left-margin
2103 @item Indent More
2104 Indent the region by 4 columns (@code{increase-left-margin}). In
2105 Enriched mode, this command is also available on @kbd{C-x @key{TAB}}; if
2106 you supply a numeric argument, that says how many columns to add to the
2107 margin (a negative argument reduces the number of columns).
2108
2109 @item Indent Less
2110 Remove 4 columns of indentation from the region.
2111
2112 @item Indent Right More
2113 Make the text narrower by indenting 4 columns at the right margin.
2114
2115 @item Indent Right Less
2116 Remove 4 columns of indentation from the right margin.
2117 @end table
2118
2119 You can use these commands repeatedly to increase or decrease the
2120 indentation.
2121
2122 The most common way to use them is to change the indentation of an
2123 entire paragraph. For other uses, the effects of refilling can be
2124 hard to predict, except in some special cases like the one described
2125 next.
2126
2127 The most common other use is to format paragraphs with @dfn{hanging
2128 indents}, which means that the first line is indented less than
2129 subsequent lines. To set up a hanging indent, increase the
2130 indentation of the region starting after the first word of the
2131 paragraph and running until the end of the paragraph.
2132
2133 Indenting the first line of a paragraph is easier. Set the margin for
2134 the whole paragraph where you want it to be for the body of the
2135 paragraph, then indent the first line by inserting extra spaces or tabs.
2136
2137 @vindex standard-indent
2138 The variable @code{standard-indent} specifies how many columns these
2139 commands should add to or subtract from the indentation. The default
2140 value is 4. The overall default right margin for Enriched mode is
2141 controlled by the variable @code{fill-column}, as usual.
2142
2143 @kindex C-c [ @r{(Enriched mode)}
2144 @kindex C-c ] @r{(Enriched mode)}
2145 @findex set-left-margin
2146 @findex set-right-margin
2147 There are also two commands for setting the left or right margin of
2148 the region absolutely: @code{set-left-margin} and
2149 @code{set-right-margin}. Enriched mode binds these commands to
2150 @kbd{C-c [} and @kbd{C-c ]}, respectively. You can specify the
2151 margin width either with a numeric argument or in the minibuffer.
2152
2153 Sometimes, as a result of editing, the filling of a paragraph becomes
2154 messed up---parts of the paragraph may extend past the left or right
2155 margins. When this happens, use @kbd{M-q} (@code{fill-paragraph}) to
2156 refill the paragraph.
2157
2158 The fill prefix, if any, works in addition to the specified paragraph
2159 indentation: @kbd{C-x .} does not include the specified indentation's
2160 whitespace in the new value for the fill prefix, and the fill commands
2161 look for the fill prefix after the indentation on each line. @xref{Fill
2162 Prefix}.
2163
2164 @node Format Justification
2165 @subsection Justification in Formatted Text
2166
2167 When editing formatted text, you can specify various styles of
2168 justification for a paragraph. The style you specify automatically
2169 affects the Emacs fill commands.
2170
2171 The Justification submenu provides a convenient interface for specifying
2172 the style. The submenu contains five items:
2173
2174 @table @code
2175 @item Left
2176 This is the most common style of justification (at least for English).
2177 Lines are aligned at the left margin but left uneven at the right.
2178
2179 @item Right
2180 This aligns each line with the right margin. Spaces and tabs are added
2181 on the left, if necessary, to make lines line up on the right.
2182
2183 @item Full
2184 This justifies the text, aligning both edges of each line. Justified
2185 text looks very nice in a printed book, where the spaces can all be
2186 adjusted equally, but it does not look as nice with a fixed-width font
2187 on the screen. Perhaps a future version of Emacs will be able to adjust
2188 the width of spaces in a line to achieve elegant justification.
2189
2190 @item Center
2191 This centers every line between the current margins.
2192
2193 @item Unfilled
2194 This turns off filling entirely. Each line will remain as you wrote it;
2195 the fill and auto-fill functions will have no effect on text which has
2196 this setting. You can, however, still indent the left margin. In
2197 unfilled regions, all newlines are treated as hard newlines (@pxref{Hard
2198 and Soft Newlines}) .
2199 @end table
2200
2201 In Enriched mode, you can also specify justification from the keyboard
2202 using the @kbd{M-j} prefix character:
2203
2204 @table @kbd
2205 @kindex M-j l @r{(Enriched mode)}
2206 @findex set-justification-left
2207 @item M-j l
2208 Make the region left-filled (@code{set-justification-left}).
2209 @kindex M-j r @r{(Enriched mode)}
2210 @findex set-justification-right
2211 @item M-j r
2212 Make the region right-filled (@code{set-justification-right}).
2213 @kindex M-j b @r{(Enriched mode)}
2214 @findex set-justification-full
2215 @item M-j b
2216 Make the region fully justified (@code{set-justification-full}).
2217 @kindex M-j c @r{(Enriched mode)}
2218 @kindex M-S @r{(Enriched mode)}
2219 @findex set-justification-center
2220 @item M-j c
2221 @itemx M-S
2222 Make the region centered (@code{set-justification-center}).
2223 @kindex M-j u @r{(Enriched mode)}
2224 @findex set-justification-none
2225 @item M-j u
2226 Make the region unfilled (@code{set-justification-none}).
2227 @end table
2228
2229 Justification styles apply to entire paragraphs. All the
2230 justification-changing commands operate on the paragraph containing
2231 point, or, if the region is active, on all paragraphs which overlap the
2232 region.
2233
2234 @vindex default-justification
2235 The default justification style is specified by the variable
2236 @code{default-justification}. Its value should be one of the symbols
2237 @code{left}, @code{right}, @code{full}, @code{center}, or @code{none}.
2238 This is a per-buffer variable. Setting the variable directly affects
2239 only the current buffer. However, customizing it in a Custom buffer
2240 sets (as always) the default value for buffers that do not override it.
2241 @xref{Locals}, and @ref{Easy Customization}.
2242
2243 @node Format Properties
2244 @subsection Setting Other Text Properties
2245
2246 The Special Properties menu lets you add or remove three other useful text
2247 properties: @code{read-only}, @code{invisible} and @code{intangible}.
2248 The @code{intangible} property disallows moving point within the text,
2249 the @code{invisible} text property hides text from display, and the
2250 @code{read-only} property disallows alteration of the text.
2251
2252 Each of these special properties has a menu item to add it to the
2253 region. The last menu item, @samp{Remove Special}, removes all of these
2254 special properties from the text in the region.
2255
2256 Currently, the @code{invisible} and @code{intangible} properties are
2257 @emph{not} saved in the text/enriched format. The @code{read-only}
2258 property is saved, but it is not a standard part of the text/enriched
2259 format, so other editors may not respect it.
2260
2261 @node Forcing Enriched Mode
2262 @subsection Forcing Enriched Mode
2263
2264 Normally, Emacs knows when you are editing formatted text because it
2265 recognizes the special annotations used in the file that you visited.
2266 However, there are situations in which you must take special actions
2267 to convert file contents or turn on Enriched mode:
2268
2269 @itemize @bullet
2270 @item
2271 When you visit a file that was created with some other editor, Emacs may
2272 not recognize the file as being in the text/enriched format. In this
2273 case, when you visit the file you will see the formatting commands
2274 rather than the formatted text. Type @kbd{M-x format-decode-buffer} to
2275 translate it. This also automatically turns on Enriched mode.
2276
2277 @item
2278 When you @emph{insert} a file into a buffer, rather than visiting it,
2279 Emacs does the necessary conversions on the text which you insert, but
2280 it does not enable Enriched mode. If you wish to do that, type @kbd{M-x
2281 enriched-mode}.
2282 @end itemize
2283
2284 The command @code{format-decode-buffer} translates text in various
2285 formats into Emacs's internal format. It asks you to specify the format
2286 to translate from; however, normally you can type just @key{RET}, which
2287 tells Emacs to guess the format.
2288
2289 @findex format-find-file
2290 If you wish to look at a text/enriched file in its raw form, as a
2291 sequence of characters rather than as formatted text, use the @kbd{M-x
2292 find-file-literally} command. This visits a file, like
2293 @code{find-file}, but does not do format conversion. It also inhibits
2294 character code conversion (@pxref{Coding Systems}) and automatic
2295 uncompression (@pxref{Compressed Files}). To disable format conversion
2296 but allow character code conversion and/or automatic uncompression if
2297 appropriate, use @code{format-find-file} with suitable arguments.
2298
2299 @node Text Based Tables
2300 @section Editing Text-based Tables
2301 @cindex table mode
2302 @cindex text-based tables
2303
2304 Table Mode provides an easy and intuitive way to create and edit WYSIWYG
2305 text-based tables. Here is an example of such a table:
2306
2307 @smallexample
2308 +-----------------+--------------------------------+-----------------+
2309 | Command | Description | Key Binding |
2310 +-----------------+--------------------------------+-----------------+
2311 | forward-char |Move point right N characters | C-f |
2312 | |(left if N is negative). | |
2313 | | | |
2314 | |On reaching end of buffer, stop | |
2315 | |and signal error. | |
2316 +-----------------+--------------------------------+-----------------+
2317 | backward-char |Move point left N characters | C-b |
2318 | |(right if N is negative). | |
2319 | | | |
2320 | |On attempt to pass beginning or | |
2321 | |end of buffer, stop and signal | |
2322 | |error. | |
2323 +-----------------+--------------------------------+-----------------+
2324 @end smallexample
2325
2326 Table Mode allows the contents of the table such as this one to be
2327 easily manipulated by inserting or deleting characters inside a cell.
2328 A cell is effectively a localized rectangular edit region and edits to
2329 a cell do not affect the contents of the surrounding cells. If the
2330 contents do not fit into a cell, then the cell is automatically
2331 expanded in the vertical and/or horizontal directions and the rest of
2332 the table is restructured and reformatted in accordance with the
2333 growth of the cell.
2334
2335 @menu
2336 * Table Definition:: What is a text based table.
2337 * Table Creation:: How to create a table.
2338 * Table Recognition:: How to activate and deactivate tables.
2339 * Cell Commands:: Cell-oriented commands in a table.
2340 * Cell Justification:: Justifying cell contents.
2341 * Row Commands:: Manipulating rows of table cell.
2342 * Column Commands:: Manipulating columns of table cell.
2343 * Fixed Width Mode:: Fixing cell width.
2344 * Table Conversion:: Converting between plain text and tables.
2345 * Measuring Tables:: Analyzing table dimension.
2346 * Table Misc:: Table miscellany.
2347 @end menu
2348
2349 @node Table Definition
2350 @subsection What is a Text-based Table?
2351
2352 Look at the following examples of valid tables as a reference while
2353 you read this section:
2354
2355 @example
2356 +--+----+---+ +-+ +--+-----+
2357 | | | | | | | | |
2358 +--+----+---+ +-+ | +--+--+
2359 | | | | | | | |
2360 +--+----+---+ +--+--+ |
2361 | | |
2362 +-----+--+
2363 @end example
2364
2365 A table consists of a rectangular frame and the contents inside the
2366 frame. A table's cells must be at least one character wide and one
2367 character high with two adjacent cells sharing a boarder line. A cell
2368 can be subdivided into multiple rectangular cells but cannot nest or
2369 overlap.
2370
2371 Both the table frame and cell border lines must consist of one of
2372 three special characters. The variables that hold these characters
2373 are described below:
2374
2375 @table @code
2376 @vindex table-cell-vertical-char
2377 @item table-cell-vertical-char
2378 Holds the character used for vertical lines. The default value is
2379 @samp{|}.
2380
2381 @vindex table-cell-horizontal-char
2382 @item table-cell-horizontal-char
2383 Holds the character used for horizontal lines. The default value is
2384 @samp{-}.
2385
2386 @vindex table-cell-intersection-char
2387 @item table-cell-intersection-char
2388 Holds the character used at where horizontal line and vertical line
2389 meet. The default value is @samp{+}.
2390 @end table
2391
2392 @noindent
2393 Based on this definition, the following five tables are examples of invalid
2394 tables:
2395
2396 @example
2397 +-----+ +-----+ +--+ +-++--+ ++
2398 | | | | | | | || | ++
2399 | +-+ | | | | | | || |
2400 | | | | +--+ | +--+--+ +-++--+
2401 | +-+ | | | | | | | +-++--+
2402 | | | | | | | | | || |
2403 +-----+ +--+--+ +--+--+ +-++--+
2404 a b c d e
2405 @end example
2406
2407 From left to right:
2408
2409 @enumerate a
2410 @item
2411 Nested cells are not allowed.
2412 @item
2413 Overlapped cells or non-rectangular cells are not allowed.
2414 @item
2415 The border must be rectangular.
2416 @item
2417 Cells must have a minimum width/height of one character.
2418 @item
2419 Same as d.
2420 @end enumerate
2421
2422 @node Table Creation
2423 @subsection How to Create a Table?
2424 @cindex create a text-based table
2425 @cindex table creation
2426
2427 @findex table-insert
2428 The command to create a table is @code{table-insert}. When called
2429 interactively, it asks for the number of columns, number of rows, cell
2430 width and cell height. The number of columns is a number of cells
2431 within the table's width. The number of rows is the number of cells
2432 within the table's height. The cell width is a number of characters
2433 that fit within a cell width. The cell height is a number of lines
2434 within cell height. While the number of columns and number of rows
2435 must be an integer number, the cell width and the cell height can be
2436 either an integer number (when the value is constant across the table)
2437 or a series of integer numbers, separated by spaces or commas, where
2438 each number corresponds to each cell width within a row from left to
2439 right or each cell height within a column from top to bottom.
2440
2441 @node Table Recognition
2442 @subsection Table Recognition
2443 @cindex table recognition
2444
2445 @findex table-recognize
2446 @findex table-unrecognize
2447 Table Mode maintains special text properties in the buffer to allow
2448 editing in a convenient fashion. When a buffer with tables is saved
2449 to its file, these text properties are lost, so when you visit this
2450 file again later, Emacs does not see a table, but just formatted text.
2451 To resurrect the table text properties, issue the @kbd{M-x
2452 table-recognize} command. It scans the current buffer, recognizes
2453 valid table cells, and attaches appropriate text properties to allow
2454 for table editing. The converse command, @code{table-unrecognize}, is
2455 used to remove the special text properties and revert the buffer back
2456 to plain text.
2457
2458 An optional numeric prefix argument can precede the
2459 @code{table-recognize} command. If the argument is negative, tables
2460 in the buffer become inactive. This is equivalent to invoking
2461 @code{table-unrecognize}.
2462
2463 Similar functions exist to enable or disable tables within a region,
2464 enable or disable individual tables, and enable/disable individual
2465 cells. These commands are:
2466
2467 @table @kbd
2468 @findex table-recognize-region
2469 @item M-x table-recognize-region
2470 Recognize tables within the current region and activate them.
2471 @findex table-unrecognize-region
2472 @item M-x table-unrecognize-region
2473 Deactivate tables within the current region.
2474 @findex table-recognize-table
2475 @item M-x table-recognize-table
2476 Recognize the table under point and activate it.
2477 @findex table-unrecognize-table
2478 @item M-x table-unrecognize-table
2479 Deactivate the table under point.
2480 @findex table-recognize-cell
2481 @item M-x table-recognize-cell
2482 Recognize the cell under point and activate it.
2483 @findex table-unrecognize-cell
2484 @item M-x table-unrecognize-cell
2485 Deactivate the cell under point.
2486 @end table
2487
2488 For another way of converting text into tables, see @ref{Table
2489 Conversion}.
2490
2491 @node Cell Commands
2492 @subsection Commands for Table Cells
2493
2494 @findex table-forward-cell
2495 @findex table-backward-cell
2496 The commands @code{table-forward-cell} and
2497 @code{table-backward-cell} move point from the current cell to an
2498 adjacent cell forward and backward respectively. The order of the
2499 cell is wrapped. When point is positioned in the last cell of a
2500 table, typing @kbd{M-x table-forward-cell} moves point to the first
2501 cell in the table. Likewise @kbd{M-x table-backward-cell} from the
2502 first cell in a table moves point to the last cell in the table.
2503
2504 @findex table-span-cell
2505 The command @code{table-span-cell} spans the current cell into one
2506 of the four directions---right, left, above or below---and merges the
2507 current cell with the adjacent cell. It does not allow directions to
2508 which spanning does not produce a legitimate cell.
2509
2510 @findex table-split-cell
2511 @cindex text-based tables, split a cell
2512 @cindex split table cell
2513 The command @code{table-split-cell} splits the current cell
2514 vertically or horizontally. This command is a wrapper to the
2515 direction specific commands @code{table-split-cell-vertically} and
2516 @code{table-split-cell-horizontally}.
2517
2518 @findex table-split-cell-vertically
2519 The command @code{table-split-cell-vertically} splits the current
2520 cell vertically and creates a pair of cells above and below where
2521 point is located. The content in the original cell is split as well.
2522
2523 @findex table-split-cell-horizontally
2524 The command @code{table-split-cell-horizontally} splits the current
2525 cell horizontally and creates a pair of cells right and left of where
2526 point is located. If the subject cell to split is not empty the user
2527 is asked how to handle the cell contents. The three options are:
2528 @code{split}, @code{left}, or @code{right}. @code{split} splits the
2529 contents at point literally while the @code{left} and @code{right}
2530 options move the entire contents into the left or right cell
2531 respectively.
2532
2533 @cindex enlarge a table cell
2534 @cindex shrink a table cell
2535 The next four commands enlarge or shrink a cell. These commands
2536 accept numeric arguments (@pxref{Arguments}) to specify how many
2537 columns or rows to enlarge or shrink a particular table.
2538
2539 @table @kbd
2540 @findex table-heighten-cell
2541 @item M-x table-heighten-cell
2542 Enlarge the current cell vertically.
2543 @findex table-shorten-cell
2544 @item M-x table-shorten-cell
2545 Shrink the current cell vertically.
2546 @findex table-widen-cell
2547 @item M-x table-widen-cell
2548 Enlarge the current cell horizontally.
2549 @findex table-narrow-cell
2550 @item M-x table-narrow-cell
2551 Shrink the current cell horizontally.
2552 @end table
2553
2554 @node Cell Justification
2555 @subsection Cell Justification
2556 @cindex cell text justification
2557
2558 You can specify text justification for each cell. The justification
2559 is remembered independently for each cell and the subsequent editing
2560 of cell contents is subject to the specified justification.
2561
2562 @findex table-justify
2563 The command @code{table-justify} requests the user to specify what
2564 to justify: a cell,a column, or a row. If you select cell
2565 justification, this command sets the justification only to the current
2566 cell. Selecting column or row justification set the justification to
2567 all the cells within a column or row respectively. The command then
2568 requests the user to enter which justification to apply: @code{left},
2569 @code{center}, @code{right}, @code{top}, @code{middle}, @code{bottom},
2570 or @code{none}. The options @code{left}, @code{center}, and
2571 @code{right} specify horizontal justification while the options
2572 @code{top}, @code{middle}, @code{bottom}, and @code{none} specify
2573 vertical justification. The vertical justification @code{none}
2574 effectively removes vertical justification while horizontal
2575 justification must be one of @code{left}, @code{center}, or
2576 @code{right}. Horizontal justification and vertical justification are
2577 specified independently.
2578
2579 @vindex table-detect-cell-alignment
2580 Justification information is stored in the buffer as a part of text
2581 property. Therefore, this information is ephemeral and does not
2582 survive through the loss of the buffer (closing the buffer and
2583 revisiting the buffer erase any previous text properties). To
2584 countermand for this, the command @code{table-recognize} and other
2585 recognition commands (@pxref{Table Recognition}) are equipped with a
2586 convenience feature (turned on by default). During table recognition,
2587 the contents of a cell are examined to determine which justification
2588 was originally applied to the cell and then applies this justification
2589 to the the cell. This is a speculative algorithm and is therefore not
2590 perfect, however, the justification is deduced correctly most of the
2591 time. If you desire to disable this feature, customize the variable
2592 @code{table-detect-cell-alignment} to set it to @code{nil}.
2593
2594 @node Row Commands
2595 @subsection Commands for Table Rows
2596 @cindex table row commands
2597
2598 @cindex insert row in table
2599 @findex table-insert-row
2600 The command @code{table-insert-row} inserts a row of cells before
2601 the current row in a table. The current row where point is located is
2602 pushed down after the newly inserted row. A numeric prefix argument
2603 specifies the number of rows to insert. Note that in order to insert
2604 rows @emph{after} the last row at the bottom of a table, you must
2605 place point below the table, i.e.@: outside the table, prior to
2606 invoking this command.
2607
2608 @cindex delete row in table
2609 @findex table-delete-row
2610 The command @code{table-delete-row} deletes a row of cells at point.
2611 A numeric prefix argument specifies the number of rows to delete.
2612
2613 @node Column Commands
2614 @subsection Commands for Table Columns
2615 @cindex table column commands
2616
2617 @cindex insert column in table
2618 @findex table-insert-column
2619 The command @code{table-insert-column} inserts a column of cells to
2620 the left of the current row in a table. The current column where
2621 point is located at is pushed right of the newly inserted column. To
2622 insert a column to the right side of the right most column, place
2623 point to the right of the rightmost column, which is outside of the
2624 table, prior to invoking this command. A numeric prefix argument
2625 specifies the number of columns to insert.
2626
2627 @cindex delete column in table
2628 A command @code{table-delete-column} deletes a column of cells at
2629 point. A numeric prefix argument specifies the number of columns to
2630 delete.
2631
2632 @node Fixed Width Mode
2633 @subsection Fix Width of Cells
2634 @cindex fix width of table cells
2635
2636 @findex table-fixed-width-mode
2637 The command @code{table-fixed-width-mode} toggles fixed width mode
2638 on and off. When the fixed width mode is turned on, editing inside a
2639 cell never changes the cell width; when it is off, the cell width
2640 expands automatically in order to prevent a word from being folded
2641 into multiple lines. By default, the fixed width mode is turned off.
2642
2643
2644 @node Table Conversion
2645 @subsection Conversion Between Plain Text and Tables
2646 @cindex text to table
2647 @cindex table to text
2648
2649 @findex table-capture
2650 The command @code{table-capture} captures plain text in a region and
2651 turns it into a table. Unlike @code{table-recognize} (@pxref{Table
2652 Recognition}), the original text does not have a table appearance but
2653 may hold a logical table structure. For example, some elements
2654 separated by known patterns form a two dimensional structure which can
2655 be turned into a table. Look at the numbers below. The numbers are
2656 horizontally separated by a comma and vertically separated by a
2657 newline character.
2658
2659 @example
2660 1, 2, 3, 4
2661 5, 6, 7, 8
2662 , 9, 10
2663 @end example
2664
2665 @noindent
2666 When you invoke @kbd{M-x table-capture} on the above three-line
2667 region, the region can be turned into the next table:
2668
2669 @example
2670 +-----+-----+-----+-----+
2671 |1 |2 |3 |4 |
2672 +-----+-----+-----+-----+
2673 |5 |6 |7 |8 |
2674 +-----+-----+-----+-----+
2675 | |9 |10 | |
2676 +-----+-----+-----+-----+
2677 @end example
2678
2679 @noindent
2680 where @samp{,} is used for a column delimiter regexp, a newline is
2681 used for a row delimiter regexp, cells are left justified, and minimum
2682 cell width is 5.
2683
2684 @findex table-release
2685 The command @code{table-release} does the opposite of
2686 @code{table-capture}. It releases a table by removing the table frame
2687 and cell borders. This leaves the table contents as plain text. One
2688 of the useful applications of @code{table-capture} and
2689 @code{table-release} is to edit a text in layout. Look at the
2690 following three paragraphs (the latter two are indented with header
2691 lines):
2692
2693 @example
2694 @samp{table-capture} is a powerful command however mastering its power
2695 requires some practice. Here is a list of items what it can do.
2696
2697 Parse Cell Items By using column delimiter regular
2698 expression and raw delimiter regular
2699 expression, it parses the specified text
2700 area and extracts cell items from
2701 non-table text and then forms a table out
2702 of them.
2703
2704 Capture Text Area When no delimiters are specified it
2705 creates a single cell table. The text in
2706 the specified region is placed in that
2707 cell.
2708 @end example
2709
2710 @noindent
2711 Applying @code{table-capture} to a region containing the above three
2712 paragraphs, with empty strings for column delimiter regexp and row
2713 delimiter regexp, creates a table with a single cell like the
2714 following one.
2715
2716 @c The first line's right-hand frame in the following two examples
2717 @c sticks out to accommodate for the removal of @samp in the
2718 @c produced output!!
2719 @example
2720 +-----------------------------------------------------------------+
2721 |@samp{table-capture} is a powerful command however mastering its |
2722 |power requires some practice. Here is a list of items what it |
2723 |can do. |
2724 | |
2725 |Parse Cell Items By using column delimiter regular |
2726 | expression and raw delimiter regular |
2727 | expression, it parses the specified text |
2728 | area and extracts cell items from |
2729 | non-table text and then forms a table out |
2730 | of them. |
2731 | |
2732 |Capture Text Area When no delimiters are specified it |
2733 | creates a single cell table. The text in |
2734 | the specified region is placed in that |
2735 | cell. |
2736 +-----------------------------------------------------------------+
2737 @end example
2738
2739 @noindent
2740 By splitting the cell appropriately we now have a table consisting of
2741 paragraphs occupying its own cell. Each cell can now be edited
2742 independently without affecting the layout of other cells.
2743
2744 @example
2745 +-----------------------------------------------------------------+
2746 |@samp{table-capture} is a powerful command however mastering its |
2747 |power requires some practice. Here is a list of items what it |
2748 |can do. |
2749 +---------------------+-------------------------------------------+
2750 |Parse Cell Items |By using column delimiter regular |
2751 | |expression and raw delimiter regular |
2752 | |expression, it parses the specified text |
2753 | |area and extracts cell items from |
2754 | |non-table text and then forms a table out |
2755 | |of them. |
2756 +---------------------+-------------------------------------------+
2757 |Capture Text Area |When no delimiters are specified it |
2758 | |creates a single cell table. The text in |
2759 | |the specified region is placed in that |
2760 | |cell. |
2761 +---------------------+-------------------------------------------+
2762 @end example
2763
2764 @noindent
2765 By applying @code{table-release}, which does the opposite process, the
2766 contents become once again plain text. @code{table-release} works as
2767 a companion command to @code{table-capture}.
2768
2769 @node Measuring Tables
2770 @subsection Analyzing Table Dimensions
2771 @cindex table dimensions
2772
2773 @findex table-query-dimension
2774 The command @code{table-query-dimension} analyzes a table structure
2775 and reports information regarding its dimensions. In case of the
2776 above example table, the @code{table-query-dimension} command displays
2777 in echo area:
2778
2779 @smallexample
2780 Cell: (21w, 6h), Table: (67w, 16h), Dim: (2c, 3r), Total Cells: 5
2781 @end smallexample
2782
2783 @noindent
2784 This indicates that the current cell is 21 character wide and 6 lines
2785 high, the entire table is 67 characters wide and 16 lines high. The
2786 table has 2 columns and 3 rows. It has a total of 5 cells, since the
2787 first row has a spanned cell.
2788
2789 @node Table Misc
2790 @subsection Table Miscellany
2791
2792 @cindex insert string into table cells
2793 @findex table-insert-sequence
2794 The command @code{table-insert-sequence} inserts a string into each
2795 cell. Each string is a part of a sequence i.e.@: a series of
2796 increasing integer numbers.
2797
2798 @cindex table in language format
2799 @cindex table for HTML and LaTeX
2800 @findex table-generate-source
2801 The command @code{table-generate-source} generates a table formatted
2802 for a specific markup language. It asks for a language (which must be
2803 one of @code{html}, @code{latex}, or @code{cals}), a destination
2804 buffer where to put the result, and the table caption (a string), and
2805 then inserts the generated table in the proper syntax into the
2806 destination buffer. The default destination buffer is
2807 @code{table.@var{lang}}, where @var{lang} is the language you
2808 specified.
2809
2810 @ignore
2811 arch-tag: 8db54ed8-2036-49ca-b0df-23811d03dc70
2812 @end ignore