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comparison man/xemacs/text.texi @ 428:3ecd8885ac67 r21-2-22
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| author | cvs |
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| date | Mon, 13 Aug 2007 11:28:15 +0200 |
| parents | |
| children | 7844ab77b582 |
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| 1 | |
| 2 @node Text, Programs, Indentation, Top | |
| 3 @chapter Commands for Human Languages | |
| 4 @cindex text | |
| 5 | |
| 6 The term @dfn{text} has two widespread meanings in our area of the | |
| 7 computer field. One is data that is a sequence of characters. In this | |
| 8 sense of the word any file that you edit with Emacs is text. The other | |
| 9 meaning is more restrictive: a sequence of characters in a human | |
| 10 language for humans to read (possibly after processing by a text | |
| 11 formatter), as opposed to a program or commands for a program. | |
| 12 | |
| 13 Human languages have syntactic and stylistic conventions that editor | |
| 14 commands should support or use to advantage: conventions involving | |
| 15 words, sentences, paragraphs, and capital letters. This chapter describes | |
| 16 Emacs commands for all these things. There are also commands for | |
| 17 @dfn{filling}, or rearranging paragraphs into lines of approximately equal | |
| 18 length. The commands for moving over and killing words, sentences, | |
| 19 and paragraphs, while intended primarily for editing text, are also often | |
| 20 useful for editing programs. | |
| 21 | |
| 22 Emacs has several major modes for editing human language text. | |
| 23 If a file contains plain text, use Text mode, which customizes | |
| 24 Emacs in small ways for the syntactic conventions of text. For text which | |
| 25 contains embedded commands for text formatters, Emacs has other major modes, | |
| 26 each for a particular text formatter. Thus, for input to @TeX{}, you can | |
| 27 use @TeX{} mode; for input to nroff, Nroff mode. | |
| 28 | |
| 29 @menu | |
| 30 * Text Mode:: The major modes for editing text files. | |
| 31 * Nroff Mode:: The major mode for editing input to the formatter nroff. | |
| 32 * TeX Mode:: The major modes for editing input to the formatter TeX. | |
| 33 * Outline Mode:: The major mode for editing outlines. | |
| 34 * Words:: Moving over and killing words. | |
| 35 * Sentences:: Moving over and killing sentences. | |
| 36 * Paragraphs:: Moving over paragraphs. | |
| 37 * Pages:: Moving over pages. | |
| 38 * Filling:: Filling or justifying text | |
| 39 * Case:: Changing the case of text | |
| 40 @end menu | |
| 41 | |
| 42 @node Text Mode, Words, Text, Text | |
| 43 @section Text Mode | |
| 44 | |
| 45 @findex tab-to-tab-stop | |
| 46 @findex edit-tab-stops | |
| 47 @cindex Text mode | |
| 48 @kindex TAB | |
| 49 @findex text-mode | |
| 50 You should use Text mode---rather than Fundamental or Lisp mode---to | |
| 51 edit files of text in a human language. Invoke @kbd{M-x text-mode} to | |
| 52 enter Text mode. In Text mode, @key{TAB} runs the function | |
| 53 @code{tab-to-tab-stop}, which allows you to use arbitrary tab stops set | |
| 54 with @kbd{M-x edit-tab-stops} (@pxref{Tab Stops}). Features concerned | |
| 55 with comments in programs are turned off unless they are explicitly invoked. | |
| 56 The syntax table is changed so that periods are not considered part of a | |
| 57 word, while apostrophes, backspaces and underlines are. | |
| 58 | |
| 59 @findex indented-text-mode | |
| 60 A similar variant mode is Indented Text mode, intended for editing | |
| 61 text in which most lines are indented. This mode defines @key{TAB} to | |
| 62 run @code{indent-relative} (@pxref{Indentation}), and makes Auto Fill | |
| 63 indent the lines it creates. As a result, a line made by Auto Filling, | |
| 64 or by @key{LFD}, is normally indented just like the previous line. Use | |
| 65 @kbd{M-x indented-text-mode} to select this mode. | |
| 66 | |
| 67 @vindex text-mode-hook | |
| 68 Entering Text mode or Indented Text mode calls the value of the | |
| 69 variable @code{text-mode-hook} with no arguments, if that value exists | |
| 70 and is not @code{nil}. This value is also called when modes related to | |
| 71 Text mode are entered; this includes Nroff mode, @TeX{} mode, Outline | |
| 72 mode, and Mail mode. Your hook can look at the value of | |
| 73 @code{major-mode} to see which of these modes is actually being entered. | |
| 74 | |
| 75 Two modes similar to Text mode are of use for editing text that is to | |
| 76 be passed through a text formatter before achieving its final readable form. | |
| 77 | |
| 78 @menu | |
| 79 * Nroff Mode:: The major mode for editing input to the formatter nroff. | |
| 80 * TeX Mode:: The major modes for editing input to the formatter TeX. | |
| 81 | |
| 82 | |
| 83 Another similar mode is used for editing outlines. It allows you | |
| 84 to view the text at various levels of detail. You can view either | |
| 85 the outline headings alone or both headings and text; you can also | |
| 86 hide some of the headings at lower levels from view to make the high | |
| 87 level structure more visible. | |
| 88 | |
| 89 | |
| 90 * Outline Mode:: The major mode for editing outlines. | |
| 91 @end menu | |
| 92 | |
| 93 @node Nroff Mode, TeX Mode, Text Mode, Text Mode | |
| 94 @subsection Nroff Mode | |
| 95 | |
| 96 @cindex nroff | |
| 97 @findex nroff-mode | |
| 98 Nroff mode is a mode like Text mode but modified to handle nroff | |
| 99 commands present in the text. Invoke @kbd{M-x nroff-mode} to enter this | |
| 100 mode. Nroff mode differs from Text mode in only a few ways. All nroff | |
| 101 command lines are considered paragraph separators, so that filling never | |
| 102 garbles the nroff commands. Pages are separated by @samp{.bp} commands. | |
| 103 Comments start with backslash-doublequote. There are also three special | |
| 104 commands that are not available in Text mode: | |
| 105 | |
| 106 @findex forward-text-line | |
| 107 @findex backward-text-line | |
| 108 @findex count-text-lines | |
| 109 @kindex M-n | |
| 110 @kindex M-p | |
| 111 @kindex M-? | |
| 112 @table @kbd | |
| 113 @item M-n | |
| 114 Move to the beginning of the next line that isn't an nroff command | |
| 115 (@code{forward-text-line}). An argument is a repeat count. | |
| 116 @item M-p | |
| 117 Like @kbd{M-n} but move up (@code{backward-text-line}). | |
| 118 @item M-? | |
| 119 Prints in the echo area the number of text lines (lines that are not | |
| 120 nroff commands) in the region (@code{count-text-lines}). | |
| 121 @end table | |
| 122 | |
| 123 @findex electric-nroff-mode | |
| 124 The other feature of Nroff mode is Electric Nroff newline mode. | |
| 125 This is a minor mode that you can turn on or off with | |
| 126 @kbd{M-x electric-nroff-mode} (@pxref{Minor Modes}). When the mode is | |
| 127 on and you use @key{RET} to end a line containing an nroff command | |
| 128 that opens a kind of grouping, Emacs automatically inserts the matching | |
| 129 nroff command to close that grouping on the following line. For | |
| 130 example, if you are at the beginning of a line and type @kbd{.@:(b | |
| 131 @key{RET}}, the matching command @samp{.)b} will be inserted on a new | |
| 132 line following point. | |
| 133 | |
| 134 @vindex nroff-mode-hook | |
| 135 Entering Nroff mode calls the value of the variable | |
| 136 @code{text-mode-hook} with no arguments, if that value exists and is not | |
| 137 @code{nil}; then it does the same with the variable | |
| 138 @code{nroff-mode-hook}. | |
| 139 | |
| 140 @node TeX Mode, Outline Mode, Nroff Mode, Text Mode | |
| 141 @subsection @TeX{} Mode | |
| 142 @cindex TeX | |
| 143 @cindex LaTeX | |
| 144 @findex TeX-mode | |
| 145 @findex tex-mode | |
| 146 @findex plain-tex-mode | |
| 147 @findex LaTeX-mode | |
| 148 @findex plain-TeX-mode | |
| 149 @findex latex-mode | |
| 150 | |
| 151 @TeX{} is a powerful text formatter written by Donald Knuth; like GNU | |
| 152 Emacs, it is free. La@TeX{} is a simplified input format for @TeX{}, | |
| 153 implemented by @TeX{} macros. It is part of @TeX{}.@refill | |
| 154 | |
| 155 Emacs has a special @TeX{} mode for editing @TeX{} input files. | |
| 156 It provides facilities for checking the balance of delimiters and for | |
| 157 invoking @TeX{} on all or part of the file. | |
| 158 | |
| 159 @TeX{} mode has two variants, Plain @TeX{} mode and La@TeX{} mode, | |
| 160 which are two distinct major modes that differ only slightly. These | |
| 161 modes are designed for editing the two different input formats. The | |
| 162 command @kbd{M-x tex-mode} looks at the contents of a buffer to | |
| 163 determine whether it appears to be La@TeX{} input or not; it then | |
| 164 selects the appropriate mode. If it can't tell which is right (e.g., | |
| 165 the buffer is empty), the variable @code{tex-default-mode} controls | |
| 166 which mode is used. | |
| 167 | |
| 168 The commands @kbd{M-x plain-tex-mode} and @kbd{M-x latex-mode} | |
| 169 explicitly select one of the variants of @TeX{} mode. Use these | |
| 170 commands when @kbd{M-x tex-mode} does not guess right.@refill | |
| 171 | |
| 172 @menu | |
| 173 * Editing: TeX Editing. Special commands for editing in TeX mode. | |
| 174 * Printing: TeX Print. Commands for printing part of a file with TeX. | |
| 175 @end menu | |
| 176 | |
| 177 @TeX{} for Unix systems can be obtained from the University of Washington | |
| 178 for a distribution fee. | |
| 179 | |
| 180 To order a full distribution, send $140.00 for a 1/2 inch | |
| 181 9-track tape, $165.00 for two 4-track 1/4 inch cartridge tapes | |
| 182 (foreign sites $150.00, for 1/2 inch, $175.00 for 1/4 inch, to cover | |
| 183 the extra postage) payable to the University of Washington to: | |
| 184 | |
| 185 @display | |
| 186 The Director | |
| 187 Northwest Computer Support Group, DW-10 | |
| 188 University of Washington | |
| 189 Seattle, Washington 98195 | |
| 190 @end display | |
| 191 | |
| 192 @noindent | |
| 193 Purchase orders are acceptable, but there is an extra charge of | |
| 194 $10.00 to pay for processing charges. (The total cost comes to $150 | |
| 195 for domestic sites, $175 for foreign sites). | |
| 196 | |
| 197 The normal distribution is a tar tape, blocked 20, 1600 bpi, on an | |
| 198 industry standard 2400 foot half-inch reel. The physical format for | |
| 199 the 1/4 inch streamer cartridges uses QIC-11, 8000 bpi, 4-track | |
| 200 serpentine recording for the SUN. Also, SystemV tapes can be written | |
| 201 in cpio format, blocked 5120 bytes, ASCII headers. | |
| 202 | |
| 203 @node TeX Editing,TeX Print,TeX Mode,TeX Mode | |
| 204 @subsubsection @TeX{} Editing Commands | |
| 205 | |
| 206 Here are the special commands provided in @TeX{} mode for editing the | |
| 207 text of the file. | |
| 208 | |
| 209 @table @kbd | |
| 210 @item " | |
| 211 Insert, according to context, either @samp{``} or @samp{"} or | |
| 212 @samp{''} (@code{TeX-insert-quote}). | |
| 213 @item @key{LFD} | |
| 214 Insert a paragraph break (two newlines) and check the previous | |
| 215 paragraph for unbalanced braces or dollar signs | |
| 216 (@code{tex-terminate-@*paragraph}). | |
| 217 @item M-x validate-tex-buffer | |
| 218 Check each paragraph in the buffer for unbalanced braces or dollar signs. | |
| 219 @item C-c @{ | |
| 220 Insert @samp{@{@}} and position point between them (@code{tex-insert-braces}). | |
| 221 @item C-c @} | |
| 222 Move forward past the next unmatched close brace (@code{up-list}). | |
| 223 @item C-c C-e | |
| 224 Close a block for La@TeX{} (@code{tex-close-latex-block}). | |
| 225 @end table | |
| 226 | |
| 227 @findex tex-insert-quote | |
| 228 @kindex " (TeX mode) | |
| 229 In @TeX{}, the character @samp{"} is not normally used; you use @samp{``} | |
| 230 to start a quotation and @samp{''} to end one. @TeX{} mode defines the key | |
| 231 @kbd{"} to insert @samp{``} after whitespace or an open brace, @samp{"} | |
| 232 after a backslash, or @samp{''} otherwise. This is done by the command | |
| 233 @code{tex-insert-quote}. If you need the character @samp{"} itself in | |
| 234 unusual contexts, use @kbd{C-q} to insert it. Also, @kbd{"} with a | |
| 235 numeric argument always inserts that number of @samp{"} characters. | |
| 236 | |
| 237 In @TeX{} mode, @samp{$} has a special syntax code which attempts to | |
| 238 understand the way @TeX{} math mode delimiters match. When you insert a | |
| 239 @samp{$} that is meant to exit math mode, the position of the matching | |
| 240 @samp{$} that entered math mode is displayed for a second. This is the | |
| 241 same feature that displays the open brace that matches a close brace that | |
| 242 is inserted. However, there is no way to tell whether a @samp{$} enters | |
| 243 math mode or leaves it; so when you insert a @samp{$} that enters math | |
| 244 mode, the previous @samp{$} position is shown as if it were a match, even | |
| 245 though they are actually unrelated. | |
| 246 | |
| 247 @findex tex-insert-braces | |
| 248 @kindex C-c @{ (TeX mode) | |
| 249 @findex up-list | |
| 250 @kindex C-c @} (TeX mode) | |
| 251 If you prefer to keep braces balanced at all times, you can use @kbd{C-c @{} | |
| 252 (@code{tex-insert-braces}) to insert a pair of braces. It leaves point | |
| 253 between the two braces so you can insert the text that belongs inside. | |
| 254 Afterward, use the command @kbd{C-c @}} (@code{up-list}) to move forward | |
| 255 past the close brace. | |
| 256 | |
| 257 @findex validate-tex-buffer | |
| 258 @findex tex-terminate-paragraph | |
| 259 @kindex LFD (TeX mode) | |
| 260 There are two commands for checking the matching of braces. @key{LFD} | |
| 261 (@code{tex-terminate-paragraph}) checks the paragraph before point, and | |
| 262 inserts two newlines to start a new paragraph. It prints a message in the | |
| 263 echo area if any mismatch is found. @kbd{M-x validate-tex-buffer} checks | |
| 264 the entire buffer, paragraph by paragraph. When it finds a paragraph that | |
| 265 contains a mismatch, it displays point at the beginning of the paragraph | |
| 266 for a few seconds and pushes a mark at that spot. Scanning continues | |
| 267 until the whole buffer has been checked or until you type another key. | |
| 268 The positions of the last several paragraphs with mismatches can be | |
| 269 found in the mark ring (@pxref{Mark Ring}). | |
| 270 | |
| 271 Note that square brackets and parentheses, not just braces, are | |
| 272 matched in @TeX{} mode. This is wrong if you want to check @TeX{} syntax. | |
| 273 However, parentheses and square brackets are likely to be used in text as | |
| 274 matching delimiters and it is useful for the various motion commands and | |
| 275 automatic match display to work with them. | |
| 276 | |
| 277 @findex tex-close-latex-block | |
| 278 @kindex C-c C-f (LaTeX mode) | |
| 279 In La@TeX{} input, @samp{\begin} and @samp{\end} commands must balance. | |
| 280 After you insert a @samp{\begin}, use @kbd{C-c C-f} | |
| 281 (@code{tex-close-latex-block}) to insert automatically a matching | |
| 282 @samp{\end} (on a new line following the @samp{\begin}). A blank line is | |
| 283 inserted between the two, and point is left there.@refill | |
| 284 | |
| 285 @node TeX Print,,TeX Editing,TeX Mode | |
| 286 @subsubsection @TeX{} Printing Commands | |
| 287 | |
| 288 You can invoke @TeX{} as an inferior of Emacs on either the entire | |
| 289 contents of the buffer or just a region at a time. Running @TeX{} in | |
| 290 this way on just one chapter is a good way to see what your changes | |
| 291 look like without taking the time to format the entire file. | |
| 292 | |
| 293 @table @kbd | |
| 294 @item C-c C-r | |
| 295 Invoke @TeX{} on the current region, plus the buffer's header | |
| 296 (@code{tex-region}). | |
| 297 @item C-c C-b | |
| 298 Invoke @TeX{} on the entire current buffer (@code{tex-buffer}). | |
| 299 @item C-c C-l | |
| 300 Recenter the window showing output from the inferior @TeX{} so that | |
| 301 the last line can be seen (@code{tex-recenter-output-buffer}). | |
| 302 @item C-c C-k | |
| 303 Kill the inferior @TeX{} (@code{tex-kill-job}). | |
| 304 @item C-c C-p | |
| 305 Print the output from the last @kbd{C-c C-r} or @kbd{C-c C-b} command | |
| 306 (@code{tex-print}). | |
| 307 @item C-c C-q | |
| 308 Show the printer queue (@code{tex-show-print-queue}). | |
| 309 @end table | |
| 310 | |
| 311 @findex tex-buffer | |
| 312 @kindex C-c C-b (TeX mode) | |
| 313 @findex tex-print | |
| 314 @kindex C-c C-p (TeX mode) | |
| 315 @findex tex-show-print-queue | |
| 316 @kindex C-c C-q (TeX mode) | |
| 317 You can pass the current buffer through an inferior @TeX{} using | |
| 318 @kbd{C-c C-b} (@code{tex-buffer}). The formatted output appears in a file | |
| 319 in @file{/tmp}; to print it, type @kbd{C-c C-p} (@code{tex-print}). | |
| 320 Afterward use @kbd{C-c C-q} (@code{tex-show-print-queue}) to view the | |
| 321 progress of your output towards being printed. | |
| 322 | |
| 323 @findex tex-kill-job | |
| 324 @kindex C-c C-k (TeX mode) | |
| 325 @findex tex-recenter-output-buffer | |
| 326 @kindex C-c C-l (TeX mode) | |
| 327 The console output from @TeX{}, including any error messages, appears in a | |
| 328 buffer called @samp{*TeX-shell*}. If @TeX{} gets an error, you can switch | |
| 329 to this buffer and feed it input (this works as in Shell mode; | |
| 330 @pxref{Interactive Shell}). Without switching to this buffer, you can scroll | |
| 331 it so that its last line is visible by typing @kbd{C-c C-l}. | |
| 332 | |
| 333 Type @kbd{C-c C-k} (@code{tex-kill-job}) to kill the @TeX{} process if | |
| 334 you see that its output is no longer useful. Using @kbd{C-c C-b} or | |
| 335 @kbd{C-c C-r} also kills any @TeX{} process still running.@refill | |
| 336 | |
| 337 @findex tex-region | |
| 338 @kindex C-c C-r (TeX mode) | |
| 339 You can pass an arbitrary region through an inferior @TeX{} by typing | |
| 340 @kbd{C-c C-r} (@code{tex-region}). This is tricky, however, because | |
| 341 most files of @TeX{} input contain commands at the beginning to set | |
| 342 parameters and define macros. Without them, no later part of the file | |
| 343 will format correctly. To solve this problem, @kbd{C-c C-r} allows you | |
| 344 to designate a part of the file as containing essential commands; it is | |
| 345 included before the specified region as part of the input to @TeX{}. | |
| 346 The designated part of the file is called the @dfn{header}. | |
| 347 | |
| 348 @cindex header (TeX mode) | |
| 349 To indicate the bounds of the header in Plain @TeX{} mode, insert two | |
| 350 special strings in the file: @samp{%**start of header} before the | |
| 351 header, and @samp{%**end of header} after it. Each string must appear | |
| 352 entirely on one line, but there may be other text on the line before or | |
| 353 after. The lines containing the two strings are included in the header. | |
| 354 If @samp{%**start of header} does not appear within the first 100 lines of | |
| 355 the buffer, @kbd{C-c C-r} assumes there is no header. | |
| 356 | |
| 357 In La@TeX{} mode, the header begins with @samp{\documentstyle} and ends | |
| 358 with @*@samp{\begin@{document@}}. These are commands that La@TeX{} requires | |
| 359 you to use, so you don't need to do anything special to identify the | |
| 360 header. | |
| 361 | |
| 362 @vindex TeX-mode-hook | |
| 363 @vindex LaTeX-mode-hook | |
| 364 @vindex plain-TeX-mode-hook | |
| 365 When you enter either kind of @TeX{} mode, Emacs calls with no | |
| 366 arguments the value of the variable @code{text-mode-hook}, if that value | |
| 367 exists and is not @code{nil}. Emacs then calls the variable | |
| 368 @code{TeX-mode-hook} and either @code{plain-TeX-mode-hook} or | |
| 369 @code{LaTeX-mode-hook} under the same conditions. | |
| 370 | |
| 371 @node Outline Mode,, TeX Mode, Text Mode | |
| 372 @subsection Outline Mode | |
| 373 @cindex outlines | |
| 374 @cindex selective display | |
| 375 @cindex invisible lines | |
| 376 | |
| 377 Outline mode is a major mode similar to Text mode but intended for editing | |
| 378 outlines. It allows you to make parts of the text temporarily invisible | |
| 379 so that you can see just the overall structure of the outline. Type | |
| 380 @kbd{M-x outline-mode} to turn on Outline mode in the current buffer. | |
| 381 | |
| 382 @vindex outline-mode-hook | |
| 383 When you enter Outline mode, Emacs calls with no arguments the value | |
| 384 of the variable @code{text-mode-hook}, if that value exists and is not | |
| 385 @code{nil}; then it does the same with the variable | |
| 386 @code{outline-mode-hook}. | |
| 387 | |
| 388 When a line is invisible in outline mode, it does not appear on the | |
| 389 screen. The screen appears exactly as if the invisible line | |
| 390 were deleted, except that an ellipsis (three periods in a row) appears | |
| 391 at the end of the previous visible line (only one ellipsis no matter | |
| 392 how many invisible lines follow). | |
| 393 | |
| 394 All editing commands treat the text of the invisible line as part of the | |
| 395 previous visible line. For example, @kbd{C-n} moves onto the next visible | |
| 396 line. Killing an entire visible line, including its terminating newline, | |
| 397 really kills all the following invisible lines as well; yanking | |
| 398 everything back yanks the invisible lines and they remain invisible. | |
| 399 | |
| 400 @menu | |
| 401 * Format: Outline Format. What the text of an outline looks like. | |
| 402 * Motion: Outline Motion. Special commands for moving through outlines. | |
| 403 * Visibility: Outline Visibility. Commands to control what is visible. | |
| 404 @end menu | |
| 405 | |
| 406 @node Outline Format,Outline Motion,Outline Mode, Outline Mode | |
| 407 @subsubsection Format of Outlines | |
| 408 | |
| 409 @cindex heading lines (Outline mode) | |
| 410 @cindex body lines (Outline mode) | |
| 411 Outline mode assumes that the lines in the buffer are of two types: | |
| 412 @dfn{heading lines} and @dfn{body lines}. A heading line represents a | |
| 413 topic in the outline. Heading lines start with one or more stars; the | |
| 414 number of stars determines the depth of the heading in the outline | |
| 415 structure. Thus, a heading line with one star is a major topic; all the | |
| 416 heading lines with two stars between it and the next one-star heading | |
| 417 are its subtopics; and so on. Any line that is not a heading line is a | |
| 418 body line. Body lines belong to the preceding heading line. Here is an | |
| 419 example: | |
| 420 | |
| 421 @example | |
| 422 * Food | |
| 423 | |
| 424 This is the body, | |
| 425 which says something about the topic of food. | |
| 426 | |
| 427 ** Delicious Food | |
| 428 | |
| 429 This is the body of the second-level header. | |
| 430 | |
| 431 ** Distasteful Food | |
| 432 | |
| 433 This could have | |
| 434 a body too, with | |
| 435 several lines. | |
| 436 | |
| 437 *** Dormitory Food | |
| 438 | |
| 439 * Shelter | |
| 440 | |
| 441 A second first-level topic with its header line. | |
| 442 @end example | |
| 443 | |
| 444 A heading line together with all following body lines is called | |
| 445 collectively an @dfn{entry}. A heading line together with all following | |
| 446 deeper heading lines and their body lines is called a @dfn{subtree}. | |
| 447 | |
| 448 @vindex outline-regexp | |
| 449 You can customize the criterion for distinguishing heading lines by | |
| 450 setting the variable @code{outline-regexp}. Any line whose beginning | |
| 451 has a match for this regexp is considered a heading line. Matches that | |
| 452 start within a line (not at the beginning) do not count. The length of | |
| 453 the matching text determines the level of the heading; longer matches | |
| 454 make a more deeply nested level. Thus, for example, if a text formatter | |
| 455 has commands @samp{@@chapter}, @samp{@@section} and @samp{@@subsection} | |
| 456 to divide the document into chapters and sections, you can make those | |
| 457 lines count as heading lines by setting @code{outline-regexp} to | |
| 458 @samp{"@@chap\\|@@\\(sub\\)*section"}. Note the trick: the two words | |
| 459 @samp{chapter} and @samp{section} are the same length, but by defining | |
| 460 the regexp to match only @samp{chap} we ensure that the length of the | |
| 461 text matched on a chapter heading is shorter, so that Outline mode will | |
| 462 know that sections are contained in chapters. This works as long as no | |
| 463 other command starts with @samp{@@chap}. | |
| 464 | |
| 465 Outline mode makes a line invisible by changing the newline before it | |
| 466 into an ASCII Control-M (code 015). Most editing commands that work on | |
| 467 lines treat an invisible line as part of the previous line because, | |
| 468 strictly speaking, it @i{is} part of that line, since there is no longer a | |
| 469 newline in between. When you save the file in Outline mode, Control-M | |
| 470 characters are saved as newlines, so the invisible lines become ordinary | |
| 471 lines in the file. Saving does not change the visibility status of a | |
| 472 line inside Emacs. | |
| 473 | |
| 474 @node Outline Motion,Outline Visibility,Outline Format,Outline Mode | |
| 475 @subsubsection Outline Motion Commands | |
| 476 | |
| 477 Some special commands in Outline mode move backward and forward to | |
| 478 heading lines. | |
| 479 | |
| 480 @table @kbd | |
| 481 @item C-c C-n | |
| 482 Move point to the next visible heading line | |
| 483 (@code{outline-next-visible-heading}). | |
| 484 @item C-c C-p | |
| 485 Move point to the previous visible heading line @* | |
| 486 (@code{outline-previous-visible-heading}). | |
| 487 @item C-c C-f | |
| 488 Move point to the next visible heading line at the same level | |
| 489 as the one point is on (@code{outline-forward-same-level}). | |
| 490 @item C-c C-b | |
| 491 Move point to the previous visible heading line at the same level | |
| 492 (@code{outline-backward-same-level}). | |
| 493 @item C-c C-u | |
| 494 Move point up to a lower-level (more inclusive) visible heading line | |
| 495 (@code{outline-up-heading}). | |
| 496 @end table | |
| 497 | |
| 498 @findex outline-next-visible-heading | |
| 499 @findex outline-previous-visible-heading | |
| 500 @kindex C-c C-n (Outline mode) | |
| 501 @kindex C-c C-p (Outline mode) | |
| 502 @kbd{C-c C-n} (@code{next-visible-heading}) moves down to the next | |
| 503 heading line. @kbd{C-c C-p} (@code{previous-visible-heading}) moves | |
| 504 similarly backward. Both accept numeric arguments as repeat counts. The | |
| 505 names emphasize that invisible headings are skipped, but this is not really | |
| 506 a special feature. All editing commands that look for lines ignore the | |
| 507 invisible lines automatically.@refill | |
| 508 | |
| 509 @findex outline-up-heading | |
| 510 @findex outline-forward-same-level | |
| 511 @findex outline-backward-same-level | |
| 512 @kindex C-c C-f (Outline mode) | |
| 513 @kindex C-c C-b (Outline mode) | |
| 514 @kindex C-c C-u (Outline mode) | |
| 515 More advanced motion commands understand the levels of headings. | |
| 516 The commands @kbd{C-c C-f} (@code{outline-forward-same-level}) and | |
| 517 @kbd{C-c C-b} (@code{outline-backward-same-level}) move from one | |
| 518 heading line to another visible heading at the same depth in | |
| 519 the outline. @kbd{C-c C-u} (@code{outline-up-heading}) moves | |
| 520 backward to another heading that is less deeply nested. | |
| 521 | |
| 522 @node Outline Visibility,,Outline Motion,Outline Mode | |
| 523 @subsubsection Outline Visibility Commands | |
| 524 | |
| 525 The other special commands of outline mode are used to make lines visible | |
| 526 or invisible. Their names all start with @code{hide} or @code{show}. | |
| 527 Most of them exist as pairs of opposites. They are not undoable; instead, | |
| 528 you can undo right past them. Making lines visible or invisible is simply | |
| 529 not recorded by the undo mechanism. | |
| 530 | |
| 531 @table @kbd | |
| 532 @item M-x hide-body | |
| 533 Make all body lines in the buffer invisible. | |
| 534 @item M-x show-all | |
| 535 Make all lines in the buffer visible. | |
| 536 @item C-c C-d | |
| 537 Make everything under this heading invisible, not including this | |
| 538 heading itself (@code{hide-subtree}). | |
| 539 @item C-c C-s | |
| 540 Make everything under this heading visible, including body, | |
| 541 subheadings, and their bodies (@code{show-subtree}). | |
| 542 @item M-x hide-leaves | |
| 543 Make the body of this heading line, and of all its subheadings, | |
| 544 invisible. | |
| 545 @item M-x show-branches | |
| 546 Make all subheadings of this heading line, at all levels, visible. | |
| 547 @item C-c C-i | |
| 548 Make immediate subheadings (one level down) of this heading line | |
| 549 visible (@code{show-children}). | |
| 550 @item M-x hide-entry | |
| 551 Make this heading line's body invisible. | |
| 552 @item M-x show-entry | |
| 553 Make this heading line's body visible. | |
| 554 @end table | |
| 555 | |
| 556 @findex hide-entry | |
| 557 @findex show-entry | |
| 558 Two commands that are exact opposites are @kbd{M-x hide-entry} and | |
| 559 @kbd{M-x show-entry}. They are used with point on a heading line, and | |
| 560 apply only to the body lines of that heading. The subtopics and their | |
| 561 bodies are not affected. | |
| 562 | |
| 563 @findex hide-subtree | |
| 564 @findex show-subtree | |
| 565 @kindex C-c C-s (Outline mode) | |
| 566 @kindex C-c C-h (Outline mode) | |
| 567 @cindex subtree (Outline mode) | |
| 568 Two more powerful opposites are @kbd{C-c C-h} (@code{hide-subtree}) and | |
| 569 @kbd{C-c C-s} (@code{show-subtree}). Both should be used when point is | |
| 570 on a heading line, and both apply to all the lines of that heading's | |
| 571 @dfn{subtree}: its body, all its subheadings, both direct and indirect, and | |
| 572 all of their bodies. In other words, the subtree contains everything | |
| 573 following this heading line, up to and not including the next heading of | |
| 574 the same or higher rank.@refill | |
| 575 | |
| 576 @findex hide-leaves | |
| 577 @findex show-branches | |
| 578 Intermediate between a visible subtree and an invisible one is having | |
| 579 all the subheadings visible but none of the body. There are two commands | |
| 580 for doing this, one that hides the bodies and one that | |
| 581 makes the subheadings visible. They are @kbd{M-x hide-leaves} and | |
| 582 @kbd{M-x show-branches}. | |
| 583 | |
| 584 @kindex C-c C-i (Outline mode) | |
| 585 @findex show-children | |
| 586 A little weaker than @code{show-branches} is @kbd{C-c C-i} | |
| 587 (@code{show-children}). It makes just the direct subheadings | |
| 588 visible---those one level down. Deeper subheadings remain | |
| 589 invisible.@refill | |
| 590 | |
| 591 @findex hide-body | |
| 592 @findex show-all | |
| 593 Two commands have a blanket effect on the whole file. @kbd{M-x | |
| 594 hide-body} makes all body lines invisible, so that you see just the | |
| 595 outline structure. @kbd{M-x show-all} makes all lines visible. You can | |
| 596 think of these commands as a pair of opposites even though @kbd{M-x | |
| 597 show-all} applies to more than just body lines. | |
| 598 | |
| 599 @vindex selective-display-ellipses | |
| 600 You can turn off the use of ellipses at the ends of visible lines by | |
| 601 setting @code{selective-display-ellipses} to @code{nil}. The result is | |
| 602 no visible indication of the presence of invisible lines. | |
| 603 | |
| 604 @node Words, Sentences, Text Mode, Text | |
| 605 @section Words | |
| 606 @cindex words | |
| 607 @cindex Meta | |
| 608 | |
| 609 Emacs has commands for moving over or operating on words. By convention, | |
| 610 the keys for them are all @kbd{Meta-} characters. | |
| 611 | |
| 612 @c widecommands | |
| 613 @table @kbd | |
| 614 @item M-f | |
| 615 Move forward over a word (@code{forward-word}). | |
| 616 @item M-b | |
| 617 Move backward over a word (@code{backward-word}). | |
| 618 @item M-d | |
| 619 Kill up to the end of a word (@code{kill-word}). | |
| 620 @item M-@key{DEL} | |
| 621 Kill back to the beginning of a word (@code{backward-kill-word}). | |
| 622 @item M-@@ | |
| 623 Mark the end of the next word (@code{mark-word}). | |
| 624 @item M-t | |
| 625 Transpose two words; drag a word forward | |
| 626 or backward across other words (@code{transpose-words}). | |
| 627 @end table | |
| 628 | |
| 629 Notice how these keys form a series that parallels the | |
| 630 character-based @kbd{C-f}, @kbd{C-b}, @kbd{C-d}, @kbd{C-t} and | |
| 631 @key{DEL}. @kbd{M-@@} is related to @kbd{C-@@}, which is an alias for | |
| 632 @kbd{C-@key{SPC}}.@refill | |
| 633 | |
| 634 @kindex M-f | |
| 635 @kindex M-b | |
| 636 @findex forward-word | |
| 637 @findex backward-word | |
| 638 The commands @kbd{Meta-f} (@code{forward-word}) and @kbd{Meta-b} | |
| 639 (@code{backward-word}) move forward and backward over words. They are | |
| 640 analogous to @kbd{Control-f} and @kbd{Control-b}, which move over single | |
| 641 characters. Like their @kbd{Control-} analogues, @kbd{Meta-f} and | |
| 642 @kbd{Meta-b} move several words if given an argument. @kbd{Meta-f} with a | |
| 643 negative argument moves backward, and @kbd{Meta-b} with a negative argument | |
| 644 moves forward. Forward motion stops after the last letter of the | |
| 645 word, while backward motion stops before the first letter.@refill | |
| 646 | |
| 647 @kindex M-d | |
| 648 @findex kill-word | |
| 649 @kbd{Meta-d} (@code{kill-word}) kills the word after point. To be | |
| 650 precise, it kills everything from point to the place @kbd{Meta-f} would | |
| 651 move to. Thus, if point is in the middle of a word, @kbd{Meta-d} kills | |
| 652 just the part after point. If some punctuation comes between point and the | |
| 653 next word, it is killed along with the word. (To kill only the | |
| 654 next word but not the punctuation before it, simply type @kbd{Meta-f} to get | |
| 655 to the end and kill the word backwards with @kbd{Meta-@key{DEL}}.) | |
| 656 @kbd{Meta-d} takes arguments just like @kbd{Meta-f}. | |
| 657 | |
| 658 @findex backward-kill-word | |
| 659 @kindex M-DEL | |
| 660 @kbd{Meta-@key{DEL}} (@code{backward-kill-word}) kills the word before | |
| 661 point. It kills everything from point back to where @kbd{Meta-b} would | |
| 662 move to. If point is after the space in @w{@samp{FOO, BAR}}, then | |
| 663 @w{@samp{FOO, }} is killed. To kill just @samp{FOO}, type | |
| 664 @kbd{Meta-b Meta-d} instead of @kbd{Meta-@key{DEL}}. | |
| 665 | |
| 666 @cindex transposition | |
| 667 @kindex M-t | |
| 668 @findex transpose-words | |
| 669 @kbd{Meta-t} (@code{transpose-words}) exchanges the word before or | |
| 670 containing point with the following word. The delimiter characters | |
| 671 between the words do not move. For example, transposing @w{@samp{FOO, | |
| 672 BAR}} results in @w{@samp{BAR, FOO}} rather than @samp{@w{BAR FOO,}}. | |
| 673 @xref{Transpose}, for more on transposition and on arguments to | |
| 674 transposition commands. | |
| 675 | |
| 676 @kindex M-@@ | |
| 677 @findex mark-word | |
| 678 To operate on the next @var{n} words with an operation which applies | |
| 679 between point and mark, you can either set the mark at point and then move | |
| 680 over the words, or you can use the command @kbd{Meta-@@} (@code{mark-word}) | |
| 681 which does not move point but sets the mark where @kbd{Meta-f} would move | |
| 682 to. It can be given arguments just like @kbd{Meta-f}. | |
| 683 | |
| 684 @cindex syntax table | |
| 685 The word commands' understanding of syntax is completely controlled by | |
| 686 the syntax table. For example, any character can be declared to be a word | |
| 687 delimiter. @xref{Syntax}. | |
| 688 | |
| 689 @node Sentences, Paragraphs, Words, Text | |
| 690 @section Sentences | |
| 691 @cindex sentences | |
| 692 | |
| 693 The Emacs commands for manipulating sentences and paragraphs are mostly | |
| 694 on @kbd{Meta-} keys, and therefore are like the word-handling commands. | |
| 695 | |
| 696 @table @kbd | |
| 697 @item M-a | |
| 698 Move back to the beginning of the sentence (@code{backward-sentence}). | |
| 699 @item M-e | |
| 700 Move forward to the end of the sentence (@code{forward-sentence}). | |
| 701 @item M-k | |
| 702 Kill forward to the end of the sentence (@code{kill-sentence}). | |
| 703 @item C-x @key{DEL} | |
| 704 Kill back to the beginning of the sentence @*(@code{backward-kill-sentence}). | |
| 705 @end table | |
| 706 | |
| 707 @kindex M-a | |
| 708 @kindex M-e | |
| 709 @findex backward-sentence | |
| 710 @findex forward-sentence | |
| 711 The commands @kbd{Meta-a} and @kbd{Meta-e} (@code{backward-sentence} | |
| 712 and @code{forward-sentence}) move to the beginning and end of the | |
| 713 current sentence, respectively. They resemble @kbd{Control-a} and | |
| 714 @kbd{Control-e}, which move to the beginning and end of a line. Unlike | |
| 715 their counterparts, @kbd{Meta-a} and @kbd{Meta-e} move over successive | |
| 716 sentences if repeated or given numeric arguments. Emacs assumes | |
| 717 the typist's convention is followed, and thus considers a sentence to | |
| 718 end wherever there is a @samp{.}, @samp{?}, or @samp{!} followed by the | |
| 719 end of a line or two spaces, with any number of @samp{)}, @samp{]}, | |
| 720 @samp{'}, or @samp{"} characters allowed in between. A sentence also | |
| 721 begins or ends wherever a paragraph begins or ends.@refill | |
| 722 | |
| 723 Neither @kbd{M-a} nor @kbd{M-e} moves past the newline or spaces beyond | |
| 724 the sentence edge at which it is stopping. | |
| 725 | |
| 726 @kindex M-k | |
| 727 @kindex C-x DEL | |
| 728 @findex kill-sentence | |
| 729 @findex backward-kill-sentence | |
| 730 @kbd{M-a} and @kbd{M-e} have a corresponding kill command, just like | |
| 731 @kbd{C-a} and @kbd{C-e} have @kbd{C-k}. The command is @kbd{M-k} | |
| 732 (@code{kill-sentence}) which kills from point to the end of the | |
| 733 sentence. With minus one as an argument it kills back to the beginning | |
| 734 of the sentence. Larger arguments serve as repeat counts.@refill | |
| 735 | |
| 736 There is a special command, @kbd{C-x @key{DEL}} | |
| 737 (@code{backward-kill-sentence}), for killing back to the beginning of a | |
| 738 sentence, which is useful when you change your mind in the middle of | |
| 739 composing text.@refill | |
| 740 | |
| 741 @vindex sentence-end | |
| 742 The variable @code{sentence-end} controls recognition of the end of a | |
| 743 sentence. It is a regexp that matches the last few characters of a | |
| 744 sentence, together with the whitespace following the sentence. Its | |
| 745 normal value is: | |
| 746 | |
| 747 @example | |
| 748 "[.?!][]\"')]*\\($\\|\t\\| \\)[ \t\n]*" | |
| 749 @end example | |
| 750 | |
| 751 @noindent | |
| 752 This example is explained in the section on regexps. @xref{Regexps}. | |
| 753 | |
| 754 @node Paragraphs, Pages, Sentences, Text | |
| 755 @section Paragraphs | |
| 756 @cindex paragraphs | |
| 757 @kindex M-[ | |
| 758 @kindex M-] | |
| 759 @findex backward-paragraph | |
| 760 @findex forward-paragraph | |
| 761 | |
| 762 The Emacs commands for manipulating paragraphs are also @kbd{Meta-} | |
| 763 keys. | |
| 764 | |
| 765 @table @kbd | |
| 766 @item M-[ | |
| 767 Move back to previous paragraph beginning @*(@code{backward-paragraph}). | |
| 768 @item M-] | |
| 769 Move forward to next paragraph end (@code{forward-paragraph}). | |
| 770 @item M-h | |
| 771 Put point and mark around this or next paragraph (@code{mark-paragraph}). | |
| 772 @end table | |
| 773 | |
| 774 @kbd{Meta-[} moves to the beginning of the current or previous paragraph, | |
| 775 while @kbd{Meta-]} moves to the end of the current or next paragraph. | |
| 776 Blank lines and text formatter command lines separate paragraphs and are | |
| 777 not part of any paragraph. An indented line starts a new paragraph. | |
| 778 | |
| 779 In major modes for programs (as opposed to Text mode), paragraphs begin | |
| 780 and end only at blank lines. As a result, the paragraph commands continue to | |
| 781 be useful even though there are no paragraphs per se. | |
| 782 | |
| 783 When there is a fill prefix, paragraphs are delimited by all lines | |
| 784 which don't start with the fill prefix. @xref{Filling}. | |
| 785 | |
| 786 @kindex M-h | |
| 787 @findex mark-paragraph | |
| 788 To operate on a paragraph, you can use the command | |
| 789 @kbd{Meta-h} (@code{mark-paragraph}) to set the region around it. This | |
| 790 command puts point at the beginning and mark at the end of the paragraph | |
| 791 point was in. If point is between paragraphs (in a run of blank lines or | |
| 792 at a boundary), the paragraph following point is surrounded by point and | |
| 793 mark. If there are blank lines preceding the first line of the paragraph, | |
| 794 one of the blank lines is included in the region. Thus, for example, | |
| 795 @kbd{M-h C-w} kills the paragraph around or after point. | |
| 796 | |
| 797 @vindex paragraph-start | |
| 798 @vindex paragraph-separate | |
| 799 The precise definition of a paragraph boundary is controlled by the | |
| 800 variables @code{paragraph-separate} and @code{paragraph-start}. The value | |
| 801 of @code{paragraph-start} is a regexp that matches any line that | |
| 802 either starts or separates paragraphs. The value of | |
| 803 @code{paragraph-separate} is another regexp that matches only lines | |
| 804 that separate paragraphs without being part of any paragraph. Lines that | |
| 805 start a new paragraph and are contained in it must match both regexps. For | |
| 806 example, normally @code{paragraph-start} is @code{"^[ @t{\}t@t{\}n@t{\}f]"} | |
| 807 and @code{paragraph-separate} is @code{"^[ @t{\}t@t{\}f]*$"}.@refill | |
| 808 | |
| 809 Normally it is desirable for page boundaries to separate paragraphs. | |
| 810 The default values of these variables recognize the usual separator for | |
| 811 pages. | |
| 812 | |
| 813 @node Pages, Filling, Paragraphs, Text | |
| 814 @section Pages | |
| 815 | |
| 816 @cindex pages | |
| 817 @cindex formfeed | |
| 818 Files are often thought of as divided into @dfn{pages} by the | |
| 819 @dfn{formfeed} character (ASCII Control-L, octal code 014). For | |
| 820 example, if a file is printed on a line printer, each ``page'' of the | |
| 821 file starts on a new page of paper. Emacs treats a page-separator | |
| 822 character just like any other character. It can be inserted with | |
| 823 @kbd{C-q C-l} or deleted with @key{DEL}. You are free to | |
| 824 paginate your file or not. However, since pages are often meaningful | |
| 825 divisions of the file, commands are provided to move over them and | |
| 826 operate on them. | |
| 827 | |
| 828 @c WideCommands | |
| 829 @table @kbd | |
| 830 @item C-x [ | |
| 831 Move point to previous page boundary (@code{backward-page}). | |
| 832 @item C-x ] | |
| 833 Move point to next page boundary (@code{forward-page}). | |
| 834 @item C-x C-p | |
| 835 Put point and mark around this page (or another page) (@code{mark-page}). | |
| 836 @item C-x l | |
| 837 Count the lines in this page (@code{count-lines-page}). | |
| 838 @end table | |
| 839 | |
| 840 @kindex C-x [ | |
| 841 @kindex C-x ] | |
| 842 @findex forward-page | |
| 843 @findex backward-page | |
| 844 The @kbd{C-x [} (@code{backward-page}) command moves point to | |
| 845 immediately after the previous page delimiter. If point is already | |
| 846 right after a page delimiter, the command skips that one and stops at | |
| 847 the previous one. A numeric argument serves as a repeat count. The | |
| 848 @kbd{C-x ]} (@code{forward-page}) command moves forward past the next | |
| 849 page delimiter. | |
| 850 | |
| 851 @kindex C-x C-p | |
| 852 @findex mark-page | |
| 853 The @kbd{C-x C-p} command (@code{mark-page}) puts point at the beginning | |
| 854 of the current page and the mark at the end. The page delimiter at the end | |
| 855 is included (the mark follows it). The page delimiter at the front is | |
| 856 excluded (point follows it). You can follow this command by @kbd{C-w} to | |
| 857 kill a page you want to move elsewhere. If you insert the page after a page | |
| 858 delimiter, at a place where @kbd{C-x ]} or @kbd{C-x [} would take you, | |
| 859 the page will be properly delimited before and after once again. | |
| 860 | |
| 861 A numeric argument to @kbd{C-x C-p} is used to specify which page to go | |
| 862 to, relative to the current one. Zero means the current page. One means | |
| 863 the next page, and @minus{}1 means the previous one. | |
| 864 | |
| 865 @kindex C-x l | |
| 866 @findex count-lines-page | |
| 867 The @kbd{C-x l} command (@code{count-lines-page}) can help you decide | |
| 868 where to break a page in two. It prints the total number of lines in | |
| 869 the current page in the echo area, then divides the lines into those | |
| 870 preceding the current line and those following it, for example | |
| 871 | |
| 872 @example | |
| 873 Page has 96 (72+25) lines | |
| 874 @end example | |
| 875 | |
| 876 @noindent | |
| 877 Notice that the sum is off by one; this is correct if point is not at the | |
| 878 beginning of a line. | |
| 879 | |
| 880 @vindex page-delimiter | |
| 881 The variable @code{page-delimiter} should have as its value a regexp that | |
| 882 matches the beginning of a line that separates pages. This defines | |
| 883 where pages begin. The normal value of this variable is @code{"^@t{\}f"}, | |
| 884 which matches a formfeed character at the beginning of a line. | |
| 885 | |
| 886 @node Filling, Case, Pages, Text | |
| 887 @section Filling Text | |
| 888 @cindex filling | |
| 889 | |
| 890 If you use Auto Fill mode, Emacs @dfn{fills} text (breaks it up into | |
| 891 lines that fit in a specified width) as you insert it. When you alter | |
| 892 existing text it is often no longer be properly filled afterwards and | |
| 893 you can use explicit commands for filling. | |
| 894 | |
| 895 @menu | |
| 896 * Auto Fill:: Auto Fill mode breaks long lines automatically. | |
| 897 * Fill Commands:: Commands to refill paragraphs and center lines. | |
| 898 * Fill Prefix:: Filling when every line is indented or in a comment, etc. | |
| 899 @end menu | |
| 900 | |
| 901 @node Auto Fill, Fill Commands, Filling, Filling | |
| 902 @subsection Auto Fill Mode | |
| 903 | |
| 904 @cindex Auto Fill mode | |
| 905 | |
| 906 @dfn{Auto Fill} mode is a minor mode in which lines are broken | |
| 907 automatically when they become too wide. Breaking happens only when | |
| 908 you type a @key{SPC} or @key{RET}. | |
| 909 | |
| 910 @table @kbd | |
| 911 @item M-x auto-fill-mode | |
| 912 Enable or disable Auto Fill mode. | |
| 913 @item @key{SPC} | |
| 914 @itemx @key{RET} | |
| 915 In Auto Fill mode, break lines when appropriate. | |
| 916 @end table | |
| 917 | |
| 918 @findex auto-fill-mode | |
| 919 @kbd{M-x auto-fill-mode} turns Auto Fill mode on if it was off, or off | |
| 920 if it was on. With a positive numeric argument the command always turns | |
| 921 Auto Fill mode on, and with a negative argument it always turns it off. | |
| 922 The presence of the word @samp{Fill} in the mode line, inside the | |
| 923 parentheses, indicates that Auto Fill mode is in effect. Auto Fill mode | |
| 924 is a minor mode; you can turn it on or off for each buffer individually. | |
| 925 @xref{Minor Modes}. | |
| 926 | |
| 927 In Auto Fill mode, lines are broken automatically at spaces when they get | |
| 928 longer than desired. Line breaking and rearrangement takes place | |
| 929 only when you type @key{SPC} or @key{RET}. To insert a space | |
| 930 or newline without permitting line-breaking, type @kbd{C-q @key{SPC}} or | |
| 931 @kbd{C-q @key{LFD}} (recall that a newline is really a linefeed). | |
| 932 @kbd{C-o} inserts a newline without line breaking. | |
| 933 | |
| 934 Auto Fill mode works well with Lisp mode: when it makes a new line in | |
| 935 Lisp mode, it indents that line with @key{TAB}. If a line ending in a | |
| 936 Lisp comment gets too long, the text of the comment is split into two | |
| 937 comment lines. Optionally, new comment delimiters are inserted at the | |
| 938 end of the first line and the beginning of the second, so that each line | |
| 939 is a separate comment. The variable @code{comment-multi-line} controls | |
| 940 the choice (@pxref{Comments}). | |
| 941 | |
| 942 Auto Fill mode does not refill entire paragraphs. It can break lines but | |
| 943 cannot merge lines. Editing in the middle of a paragraph can result in | |
| 944 a paragraph that is not correctly filled. The easiest way to make the | |
| 945 paragraph properly filled again is using an explicit fill commands. | |
| 946 | |
| 947 Many users like Auto Fill mode and want to use it in all text files. | |
| 948 The section on init files explains how you can arrange this | |
| 949 permanently for yourself. @xref{Init File}. | |
| 950 | |
| 951 @node Fill Commands, Fill Prefix, Auto Fill, Filling | |
| 952 @subsection Explicit Fill Commands | |
| 953 | |
| 954 @table @kbd | |
| 955 @item M-q | |
| 956 Fill current paragraph (@code{fill-paragraph}). | |
| 957 @item M-g | |
| 958 Fill each paragraph in the region (@code{fill-region}). | |
| 959 @item C-x f | |
| 960 Set the fill column (@code{set-fill-column}). | |
| 961 @item M-x fill-region-as-paragraph | |
| 962 Fill the region, considering it as one paragraph. | |
| 963 @item M-s | |
| 964 Center a line. | |
| 965 @end table | |
| 966 | |
| 967 @kindex M-q | |
| 968 @findex fill-paragraph | |
| 969 To refill a paragraph, use the command @kbd{Meta-q} | |
| 970 (@code{fill-paragraph}). It causes the paragraph containing point, or | |
| 971 the one after point if point is between paragraphs, to be refilled. All | |
| 972 line breaks are removed, and new ones are inserted where necessary. | |
| 973 @kbd{M-q} can be undone with @kbd{C-_}. @xref{Undo}.@refill | |
| 974 | |
| 975 @kindex M-g | |
| 976 @findex fill-region | |
| 977 To refill many paragraphs, use @kbd{M-g} (@code{fill-region}), which | |
| 978 divides the region into paragraphs and fills each of them. | |
| 979 | |
| 980 @findex fill-region-as-paragraph | |
| 981 @kbd{Meta-q} and @kbd{Meta-g} use the same criteria as @kbd{Meta-h} for | |
| 982 finding paragraph boundaries (@pxref{Paragraphs}). For more control, you | |
| 983 can use @kbd{M-x fill-region-as-paragraph}, which refills everything | |
| 984 between point and mark. This command recognizes only blank lines as | |
| 985 paragraph separators.@refill | |
| 986 | |
| 987 @cindex justification | |
| 988 A numeric argument to @kbd{M-g} or @kbd{M-q} causes it to | |
| 989 @dfn{justify} the text as well as filling it. Extra spaces are inserted | |
| 990 to make the right margin line up exactly at the fill column. To remove | |
| 991 the extra spaces, use @kbd{M-q} or @kbd{M-g} with no argument.@refill | |
| 992 | |
| 993 @vindex auto-fill-inhibit-regexp | |
| 994 The variable @code{auto-fill-inhibit-regexp} takes as a value a regexp to | |
| 995 match lines that should not be auto-filled. | |
| 996 | |
| 997 @kindex M-s | |
| 998 @cindex centering | |
| 999 @findex center-line | |
| 1000 The command @kbd{Meta-s} (@code{center-line}) centers the current line | |
| 1001 within the current fill column. With an argument, it centers several lines | |
| 1002 individually and moves past them. | |
| 1003 | |
| 1004 @vindex fill-column | |
| 1005 The maximum line width for filling is in the variable | |
| 1006 @code{fill-column}. Altering the value of @code{fill-column} makes it | |
| 1007 local to the current buffer; until then, the default value---initially | |
| 1008 70---is in effect. @xref{Locals}. | |
| 1009 | |
| 1010 @kindex C-x f | |
| 1011 @findex set-fill-column | |
| 1012 The easiest way to set @code{fill-column} is to use the command @kbd{C-x | |
| 1013 f} (@code{set-fill-column}). With no argument, it sets @code{fill-column} | |
| 1014 to the current horizontal position of point. With a numeric argument, it | |
| 1015 uses that number as the new fill column. | |
| 1016 | |
| 1017 @node Fill Prefix,, Fill Commands, Filling | |
| 1018 @subsection The Fill Prefix | |
| 1019 | |
| 1020 @cindex fill prefix | |
| 1021 To fill a paragraph in which each line starts with a special marker | |
| 1022 (which might be a few spaces, giving an indented paragraph), use the | |
| 1023 @dfn{fill prefix} feature. The fill prefix is a string which is not | |
| 1024 included in filling. Emacs expects every line to start with a fill | |
| 1025 prefix. | |
| 1026 | |
| 1027 @table @kbd | |
| 1028 @item C-x . | |
| 1029 Set the fill prefix (@code{set-fill-prefix}). | |
| 1030 @item M-q | |
| 1031 Fill a paragraph using current fill prefix (@code{fill-paragraph}). | |
| 1032 @item M-x fill-individual-paragraphs | |
| 1033 Fill the region, considering each change of indentation as starting a | |
| 1034 new paragraph. | |
| 1035 @end table | |
| 1036 | |
| 1037 @kindex C-x . | |
| 1038 @findex set-fill-prefix | |
| 1039 To specify a fill prefix, move to a line that starts with the desired | |
| 1040 prefix, put point at the end of the prefix, and give the command | |
| 1041 @w{@kbd{C-x .}}@: (@code{set-fill-prefix}). That's a period after the | |
| 1042 @kbd{C-x}. To turn off the fill prefix, specify an empty prefix: type | |
| 1043 @w{@kbd{C-x .}}@: with point at the beginning of a line.@refill | |
| 1044 | |
| 1045 When a fill prefix is in effect, the fill commands remove the fill | |
| 1046 prefix from each line before filling and insert it on each line after | |
| 1047 filling. Auto Fill mode also inserts the fill prefix inserted on new | |
| 1048 lines it creates. Lines that do not start with the fill prefix are | |
| 1049 considered to start paragraphs, both in @kbd{M-q} and the paragraph | |
| 1050 commands; this is just right if you are using paragraphs with hanging | |
| 1051 indentation (every line indented except the first one). Lines which are | |
| 1052 blank or indented once the prefix is removed also separate or start | |
| 1053 paragraphs; this is what you want if you are writing multi-paragraph | |
| 1054 comments with a comment delimiter on each line. | |
| 1055 | |
| 1056 @vindex fill-prefix | |
| 1057 The fill prefix is stored in the variable @code{fill-prefix}. Its value | |
| 1058 is a string, or @code{nil} when there is no fill prefix. This is a | |
| 1059 per-buffer variable; altering the variable affects only the current buffer, | |
| 1060 but there is a default value which you can change as well. @xref{Locals}. | |
| 1061 | |
| 1062 @findex fill-individual-paragraphs | |
| 1063 Another way to use fill prefixes is through @kbd{M-x | |
| 1064 fill-individual-paragraphs}. This function divides the region into groups | |
| 1065 of consecutive lines with the same amount and kind of indentation and fills | |
| 1066 each group as a paragraph, using its indentation as a fill prefix. | |
| 1067 | |
| 1068 @node Case,, Filling, Text | |
| 1069 @section Case Conversion Commands | |
| 1070 @cindex case conversion | |
| 1071 | |
| 1072 Emacs has commands for converting either a single word or any arbitrary | |
| 1073 range of text to upper case or to lower case. | |
| 1074 | |
| 1075 @c WideCommands | |
| 1076 @table @kbd | |
| 1077 @item M-l | |
| 1078 Convert following word to lower case (@code{downcase-word}). | |
| 1079 @item M-u | |
| 1080 Convert following word to upper case (@code{upcase-word}). | |
| 1081 @item M-c | |
| 1082 Capitalize the following word (@code{capitalize-word}). | |
| 1083 @item C-x C-l | |
| 1084 Convert region to lower case (@code{downcase-region}). | |
| 1085 @item C-x C-u | |
| 1086 Convert region to upper case (@code{upcase-region}). | |
| 1087 @end table | |
| 1088 | |
| 1089 @kindex M-l | |
| 1090 @kindex M-u | |
| 1091 @kindex M-c | |
| 1092 @cindex words | |
| 1093 @findex downcase-word | |
| 1094 @findex upcase-word | |
| 1095 @findex capitalize-word | |
| 1096 The word conversion commands are used most frequently. @kbd{Meta-l} | |
| 1097 (@code{downcase-word}) converts the word after point to lower case, | |
| 1098 moving past it. Thus, repeating @kbd{Meta-l} converts successive words. | |
| 1099 @kbd{Meta-u} (@code{upcase-word}) converts to all capitals instead, | |
| 1100 while @kbd{Meta-c} (@code{capitalize-word}) puts the first letter of the | |
| 1101 word into upper case and the rest into lower case. The word conversion | |
| 1102 commands convert several words at once if given an argument. They are | |
| 1103 especially convenient for converting a large amount of text from all | |
| 1104 upper case to mixed case: you can move through the text using | |
| 1105 @kbd{M-l}, @kbd{M-u}, or @kbd{M-c} on each word as appropriate, | |
| 1106 occasionally using @kbd{M-f} instead to skip a word. | |
| 1107 | |
| 1108 When given a negative argument, the word case conversion commands apply | |
| 1109 to the appropriate number of words before point, but do not move point. | |
| 1110 This is convenient when you have just typed a word in the wrong case: you | |
| 1111 can give the case conversion command and continue typing. | |
| 1112 | |
| 1113 If a word case conversion command is given in the middle of a word, it | |
| 1114 applies only to the part of the word which follows point. This is just | |
| 1115 like what @kbd{Meta-d} (@code{kill-word}) does. With a negative argument, | |
| 1116 case conversion applies only to the part of the word before point. | |
| 1117 | |
| 1118 @kindex C-x C-l | |
| 1119 @kindex C-x C-u | |
| 1120 @cindex region | |
| 1121 @findex downcase-region | |
| 1122 @findex upcase-region | |
| 1123 The other case conversion commands are @kbd{C-x C-u} | |
| 1124 (@code{upcase-region}) and @kbd{C-x C-l} (@code{downcase-region}), which | |
| 1125 convert everything between point and mark to the specified case. Point and | |
| 1126 mark do not move.@refill |