1;;; indent.el --- indentation commands for Emacs 2 3;; Copyright (C) 1985, 1995, 2001, 2002, 2003, 2004, 4;; 2005, 2006, 2007 Free Software Foundation, Inc. 5 6;; Maintainer: FSF 7 8;; This file is part of GNU Emacs. 9 10;; GNU Emacs is free software; you can redistribute it and/or modify 11;; it under the terms of the GNU General Public License as published by 12;; the Free Software Foundation; either version 2, or (at your option) 13;; any later version. 14 15;; GNU Emacs is distributed in the hope that it will be useful, 16;; but WITHOUT ANY WARRANTY; without even the implied warranty of 17;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 18;; GNU General Public License for more details. 19 20;; You should have received a copy of the GNU General Public License 21;; along with GNU Emacs; see the file COPYING. If not, write to the 22;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 23;; Boston, MA 02110-1301, USA. 24 25;;; Commentary: 26 27;; Commands for making and changing indentation in text. These are 28;; described in the Emacs manual. 29 30;;; Code: 31 32(defgroup indent nil 33 "Indentation commands." 34 :group 'editing) 35 36(defcustom standard-indent 4 37 "*Default number of columns for margin-changing functions to indent." 38 :group 'indent 39 :type 'integer) 40 41(defvar indent-line-function 'indent-relative 42 "Function to indent the current line. 43This function will be called with no arguments. 44If it is called somewhere where auto-indentation cannot be done 45\(f.ex. inside a string), the function should simply return `noindent'. 46Setting this function is all you need to make TAB indent appropriately. 47Don't rebind TAB unless you really need to.") 48 49(defcustom tab-always-indent t 50 "*Controls the operation of the TAB key. 51If t, hitting TAB always just indents the current line. 52If nil, hitting TAB indents the current line if point is at the left margin 53or in the line's indentation, otherwise it insert a \"real\" TAB character. 54Most programming language modes have their own variable to control this, 55e.g., `c-tab-always-indent', and do not respect this variable." 56 :group 'indent 57 :type '(choice (const nil) (const t) (const always))) 58 59(defun indent-according-to-mode () 60 "Indent line in proper way for current major mode. 61The buffer-local variable `indent-line-function' determines how to do this, 62but the functions `indent-relative' and `indent-relative-maybe' are 63special; we don't actually use them here." 64 (interactive) 65 (if (memq indent-line-function 66 '(indent-relative indent-relative-maybe)) 67 ;; These functions are used for tabbing, but can't be used for 68 ;; indenting. Replace with something ad-hoc. 69 (let ((column (save-excursion 70 (beginning-of-line) 71 (skip-chars-backward "\n \t") 72 (beginning-of-line) 73 (current-indentation)))) 74 (if (<= (current-column) (current-indentation)) 75 (indent-line-to column) 76 (save-excursion (indent-line-to column)))) 77 ;; The normal case. 78 (funcall indent-line-function))) 79 80(defun indent-for-tab-command (&optional arg) 81 "Indent line in proper way for current major mode or insert a tab. 82Depending on `tab-always-indent', either insert a tab or indent. 83If initial point was within line's indentation, position after 84the indentation. Else stay at same point in text. 85The function actually called to indent is determined by the value of 86`indent-line-function'." 87 (interactive "P") 88 (cond 89 ((or ;; indent-to-left-margin is only meant for indenting, 90 ;; so we force it to always insert a tab here. 91 (eq indent-line-function 'indent-to-left-margin) 92 (and (not tab-always-indent) 93 (or (> (current-column) (current-indentation)) 94 (eq this-command last-command)))) 95 (insert-tab arg)) 96 ;; Those functions are meant specifically for tabbing and not for 97 ;; indenting, so we can't pass them to indent-according-to-mode. 98 ((memq indent-line-function '(indent-relative indent-relative-maybe)) 99 (funcall indent-line-function)) 100 (t ;; The normal case. 101 (indent-according-to-mode)))) 102 103(defun insert-tab (&optional arg) 104 (let ((count (prefix-numeric-value arg))) 105 (if (and abbrev-mode 106 (eq (char-syntax (preceding-char)) ?w)) 107 (expand-abbrev)) 108 (if indent-tabs-mode 109 (insert-char ?\t count) 110 (indent-to (* tab-width (+ count (/ (current-column) tab-width))))))) 111 112(defun indent-rigidly (start end arg) 113 "Indent all lines starting in the region sideways by ARG columns. 114Called from a program, takes three arguments, START, END and ARG. 115You can remove all indentation from a region by giving a large negative ARG." 116 (interactive "r\np") 117 (save-excursion 118 (goto-char end) 119 (setq end (point-marker)) 120 (goto-char start) 121 (or (bolp) (forward-line 1)) 122 (while (< (point) end) 123 (let ((indent (current-indentation)) 124 eol-flag) 125 (save-excursion 126 (skip-chars-forward " \t") 127 (setq eol-flag (eolp))) 128 (or eol-flag 129 (indent-to (max 0 (+ indent arg)) 0)) 130 (delete-region (point) (progn (skip-chars-forward " \t") (point)))) 131 (forward-line 1)) 132 (move-marker end nil))) 133 134(defun indent-line-to (column) 135 "Indent current line to COLUMN. 136This function removes or adds spaces and tabs at beginning of line 137only if necessary. It leaves point at end of indentation." 138 (back-to-indentation) 139 (let ((cur-col (current-column))) 140 (cond ((< cur-col column) 141 (if (>= (- column (* (/ cur-col tab-width) tab-width)) tab-width) 142 (delete-region (point) 143 (progn (skip-chars-backward " ") (point)))) 144 (indent-to column)) 145 ((> cur-col column) ; too far right (after tab?) 146 (delete-region (progn (move-to-column column t) (point)) 147 (progn (back-to-indentation) (point))))))) 148 149(defun current-left-margin () 150 "Return the left margin to use for this line. 151This is the value of the buffer-local variable `left-margin' plus the value 152of the `left-margin' text-property at the start of the line." 153 (save-excursion 154 (back-to-indentation) 155 (max 0 156 (+ left-margin (or (get-text-property 157 (if (and (eobp) (not (bobp))) 158 (1- (point)) (point)) 159 'left-margin) 0))))) 160 161(defun move-to-left-margin (&optional n force) 162 "Move to the left margin of the current line. 163With optional argument, move forward N-1 lines first. 164The column moved to is the one given by the `current-left-margin' function. 165If the line's indentation appears to be wrong, and this command is called 166interactively or with optional argument FORCE, it will be fixed." 167 (interactive (list (prefix-numeric-value current-prefix-arg) t)) 168 (beginning-of-line n) 169 (skip-chars-forward " \t") 170 (if (minibufferp (current-buffer)) 171 (if (save-excursion (beginning-of-line) (bobp)) 172 (goto-char (minibuffer-prompt-end)) 173 (beginning-of-line)) 174 (let ((lm (current-left-margin)) 175 (cc (current-column))) 176 (cond ((> cc lm) 177 (if (> (move-to-column lm force) lm) 178 ;; If lm is in a tab and we are not forcing, move before tab 179 (backward-char 1))) 180 ((and force (< cc lm)) 181 (indent-to-left-margin)))))) 182 183;; This used to be the default indent-line-function, 184;; used in Fundamental Mode, Text Mode, etc. 185(defun indent-to-left-margin () 186 "Indent current line to the column given by `current-left-margin'." 187 (indent-line-to (current-left-margin))) 188 189(defun delete-to-left-margin (&optional from to) 190 "Remove left margin indentation from a region. 191This deletes to the column given by `current-left-margin'. 192In no case will it delete non-whitespace. 193Args FROM and TO are optional; default is the whole buffer." 194 (save-excursion 195 (goto-char (or to (point-max))) 196 (setq to (point-marker)) 197 (goto-char (or from (point-min))) 198 (or (bolp) (forward-line 1)) 199 (while (< (point) to) 200 (delete-region (point) (progn (move-to-left-margin nil t) (point))) 201 (forward-line 1)) 202 (move-marker to nil))) 203 204(defun set-left-margin (from to width) 205 "Set the left margin of the region to WIDTH. 206If `auto-fill-mode' is active, re-fill the region to fit the new margin. 207 208Interactively, WIDTH is the prefix argument, if specified. 209Without prefix argument, the command prompts for WIDTH." 210 (interactive "r\nNSet left margin to column: ") 211 (save-excursion 212 ;; If inside indentation, start from BOL. 213 (goto-char from) 214 (skip-chars-backward " \t") 215 (if (bolp) (setq from (point))) 216 ;; Place end after whitespace 217 (goto-char to) 218 (skip-chars-forward " \t") 219 (setq to (point-marker))) 220 ;; Delete margin indentation first, but keep paragraph indentation. 221 (delete-to-left-margin from to) 222 (put-text-property from to 'left-margin width) 223 (indent-rigidly from to width) 224 (if auto-fill-function (save-excursion (fill-region from to nil t t))) 225 (move-marker to nil)) 226 227(defun set-right-margin (from to width) 228 "Set the right margin of the region to WIDTH. 229If `auto-fill-mode' is active, re-fill the region to fit the new margin. 230 231Interactively, WIDTH is the prefix argument, if specified. 232Without prefix argument, the command prompts for WIDTH." 233 (interactive "r\nNSet right margin to width: ") 234 (save-excursion 235 (goto-char from) 236 (skip-chars-backward " \t") 237 (if (bolp) (setq from (point)))) 238 (put-text-property from to 'right-margin width) 239 (if auto-fill-function (save-excursion (fill-region from to nil t t)))) 240 241(defun alter-text-property (from to prop func &optional object) 242 "Programmatically change value of a text-property. 243For each region between FROM and TO that has a single value for PROPERTY, 244apply FUNCTION to that value and sets the property to the function's result. 245Optional fifth argument OBJECT specifies the string or buffer to operate on." 246 (let ((begin from) 247 end val) 248 (while (setq val (get-text-property begin prop object) 249 end (text-property-not-all begin to prop val object)) 250 (put-text-property begin end prop (funcall func val) object) 251 (setq begin end)) 252 (if (< begin to) 253 (put-text-property begin to prop (funcall func val) object)))) 254 255(defun increase-left-margin (from to inc) 256 "Increase or decrease the left-margin of the region. 257With no prefix argument, this adds `standard-indent' of indentation. 258A prefix arg (optional third arg INC noninteractively) specifies the amount 259to change the margin by, in characters. 260If `auto-fill-mode' is active, re-fill the region to fit the new margin." 261 (interactive "*r\nP") 262 (setq inc (if inc (prefix-numeric-value inc) standard-indent)) 263 (save-excursion 264 (goto-char from) 265 (skip-chars-backward " \t") 266 (if (bolp) (setq from (point))) 267 (goto-char to) 268 (setq to (point-marker))) 269 (alter-text-property from to 'left-margin 270 (lambda (v) (max (- left-margin) (+ inc (or v 0))))) 271 (indent-rigidly from to inc) 272 (if auto-fill-function (save-excursion (fill-region from to nil t t))) 273 (move-marker to nil)) 274 275(defun decrease-left-margin (from to inc) 276 "Make the left margin of the region smaller. 277With no prefix argument, decrease the indentation by `standard-indent'. 278A prefix arg (optional third arg INC noninteractively) specifies the amount 279to change the margin by, in characters. 280If `auto-fill-mode' is active, re-fill the region to fit the new margin." 281 (interactive "*r\nP") 282 (setq inc (if inc (prefix-numeric-value inc) standard-indent)) 283 (increase-left-margin from to (- inc))) 284 285(defun increase-right-margin (from to inc) 286 "Increase the right-margin of the region. 287With no prefix argument, increase the right margin by `standard-indent'. 288A prefix arg (optional third arg INC noninteractively) specifies the amount 289to change the margin by, in characters. A negative argument decreases 290the right margin width. 291If `auto-fill-mode' is active, re-fill the region to fit the new margin." 292 (interactive "r\nP") 293 (setq inc (if inc (prefix-numeric-value inc) standard-indent)) 294 (save-excursion 295 (alter-text-property from to 'right-margin 296 (lambda (v) (+ inc (or v 0)))) 297 (if auto-fill-function 298 (fill-region from to nil t t)))) 299 300(defun decrease-right-margin (from to inc) 301 "Make the right margin of the region smaller. 302With no prefix argument, decrease the right margin by `standard-indent'. 303A prefix arg (optional third arg INC noninteractively) specifies the amount 304of width to remove, in characters. A negative argument increases 305the right margin width. 306If `auto-fill-mode' is active, re-fills region to fit in new margin." 307 (interactive "*r\nP") 308 (setq inc (if inc (prefix-numeric-value inc) standard-indent)) 309 (increase-right-margin from to (- inc))) 310 311(defun beginning-of-line-text (&optional n) 312 "Move to the beginning of the text on this line. 313With optional argument, move forward N-1 lines first. 314From the beginning of the line, moves past the left-margin indentation, the 315fill-prefix, and any indentation used for centering or right-justifying the 316line, but does not move past any whitespace that was explicitly inserted 317\(such as a tab used to indent the first line of a paragraph)." 318 (interactive "p") 319 (beginning-of-line n) 320 (skip-chars-forward " \t") 321 ;; Skip over fill-prefix. 322 (if (and fill-prefix 323 (not (string-equal fill-prefix ""))) 324 (if (equal fill-prefix 325 (buffer-substring 326 (point) (min (point-max) (+ (length fill-prefix) (point))))) 327 (forward-char (length fill-prefix))) 328 (if (and adaptive-fill-mode adaptive-fill-regexp 329 (looking-at adaptive-fill-regexp)) 330 (goto-char (match-end 0)))) 331 ;; Skip centering or flushright indentation 332 (if (memq (current-justification) '(center right)) 333 (skip-chars-forward " \t"))) 334 335(defvar indent-region-function nil 336 "Short cut function to indent region using `indent-according-to-mode'. 337A value of nil means really run `indent-according-to-mode' on each line.") 338 339(defun indent-region (start end &optional column) 340 "Indent each nonblank line in the region. 341A numeric prefix argument specifies a column: indent each line to that column. 342 343With no prefix argument, the command chooses one of these methods and 344indents all the lines with it: 345 346 1) If `fill-prefix' is non-nil, insert `fill-prefix' at the 347 beginning of each line in the region that does not already begin 348 with it. 349 2) If `indent-region-function' is non-nil, call that function 350 to indent the region. 351 3) Indent each line as specified by the variable `indent-line-function'. 352 353Called from a program, START and END specify the region to indent. 354If the third argument COLUMN is an integer, it specifies the 355column to indent to; if it is nil, use one of the three methods above." 356 (interactive "r\nP") 357 (if (null column) 358 (if fill-prefix 359 (save-excursion 360 (goto-char end) 361 (setq end (point-marker)) 362 (goto-char start) 363 (let ((regexp (regexp-quote fill-prefix))) 364 (while (< (point) end) 365 (or (looking-at regexp) 366 (and (bolp) (eolp)) 367 (insert fill-prefix)) 368 (forward-line 1)))) 369 (if indent-region-function 370 (funcall indent-region-function start end) 371 (save-excursion 372 (setq end (copy-marker end)) 373 (goto-char start) 374 (while (< (point) end) 375 (or (and (bolp) (eolp)) 376 (funcall indent-line-function)) 377 (forward-line 1)) 378 (move-marker end nil)))) 379 (setq column (prefix-numeric-value column)) 380 (save-excursion 381 (goto-char end) 382 (setq end (point-marker)) 383 (goto-char start) 384 (or (bolp) (forward-line 1)) 385 (while (< (point) end) 386 (delete-region (point) (progn (skip-chars-forward " \t") (point))) 387 (or (eolp) 388 (indent-to column 0)) 389 (forward-line 1)) 390 (move-marker end nil)))) 391 392(defun indent-relative-maybe () 393 "Indent a new line like previous nonblank line. 394If the previous nonblank line has no indent points beyond the 395column point starts at, this command does nothing. 396 397See also `indent-relative'." 398 (interactive) 399 (indent-relative t)) 400 401(defun indent-relative (&optional unindented-ok) 402 "Space out to under next indent point in previous nonblank line. 403An indent point is a non-whitespace character following whitespace. 404The following line shows the indentation points in this line. 405 ^ ^ ^ ^ ^ ^ ^ ^ ^ 406If the previous nonblank line has no indent points beyond the 407column point starts at, `tab-to-tab-stop' is done instead, unless 408this command is invoked with a numeric argument, in which case it 409does nothing. 410 411See also `indent-relative-maybe'." 412 (interactive "P") 413 (if (and abbrev-mode 414 (eq (char-syntax (preceding-char)) ?w)) 415 (expand-abbrev)) 416 (let ((start-column (current-column)) 417 indent) 418 (save-excursion 419 (beginning-of-line) 420 (if (re-search-backward "^[^\n]" nil t) 421 (let ((end (save-excursion (forward-line 1) (point)))) 422 (move-to-column start-column) 423 ;; Is start-column inside a tab on this line? 424 (if (> (current-column) start-column) 425 (backward-char 1)) 426 (or (looking-at "[ \t]") 427 unindented-ok 428 (skip-chars-forward "^ \t" end)) 429 (skip-chars-forward " \t" end) 430 (or (= (point) end) (setq indent (current-column)))))) 431 (if indent 432 (let ((opoint (point-marker))) 433 (indent-to indent 0) 434 (if (> opoint (point)) 435 (goto-char opoint)) 436 (move-marker opoint nil)) 437 (tab-to-tab-stop)))) 438 439(defcustom tab-stop-list 440 '(8 16 24 32 40 48 56 64 72 80 88 96 104 112 120) 441 "*List of tab stop positions used by `tab-to-tab-stop'. 442This should be a list of integers, ordered from smallest to largest." 443 :group 'indent 444 :type '(repeat integer)) 445 446(defvar edit-tab-stops-map 447 (let ((map (make-sparse-keymap))) 448 (define-key map "\C-x\C-s" 'edit-tab-stops-note-changes) 449 (define-key map "\C-c\C-c" 'edit-tab-stops-note-changes) 450 map) 451 "Keymap used in `edit-tab-stops'.") 452 453(defvar edit-tab-stops-buffer nil 454 "Buffer whose tab stops are being edited. 455This matters if the variable `tab-stop-list' is local in that buffer.") 456 457(defun edit-tab-stops () 458 "Edit the tab stops used by `tab-to-tab-stop'. 459Creates a buffer *Tab Stops* containing text describing the tab stops. 460A colon indicates a column where there is a tab stop. 461You can add or remove colons and then do \\<edit-tab-stops-map>\\[edit-tab-stops-note-changes] to make changes take effect." 462 (interactive) 463 (setq edit-tab-stops-buffer (current-buffer)) 464 (switch-to-buffer (get-buffer-create "*Tab Stops*")) 465 (use-local-map edit-tab-stops-map) 466 (make-local-variable 'indent-tabs-mode) 467 (setq indent-tabs-mode nil) 468 (overwrite-mode 1) 469 (setq truncate-lines t) 470 (erase-buffer) 471 (let ((tabs tab-stop-list)) 472 (while tabs 473 (indent-to (car tabs) 0) 474 (insert ?:) 475 (setq tabs (cdr tabs)))) 476 (let ((count 0)) 477 (insert ?\n) 478 (while (< count 8) 479 (insert (+ count ?0)) 480 (insert " ") 481 (setq count (1+ count))) 482 (insert ?\n) 483 (while (> count 0) 484 (insert "0123456789") 485 (setq count (1- count)))) 486 (insert "\nTo install changes, type C-c C-c") 487 (goto-char (point-min))) 488 489(defun edit-tab-stops-note-changes () 490 "Put edited tab stops into effect." 491 (interactive) 492 (let (tabs) 493 (save-excursion 494 (goto-char 1) 495 (end-of-line) 496 (while (search-backward ":" nil t) 497 (setq tabs (cons (current-column) tabs)))) 498 (bury-buffer (prog1 (current-buffer) 499 (switch-to-buffer edit-tab-stops-buffer))) 500 (setq tab-stop-list tabs)) 501 (message "Tab stops installed")) 502 503(defun tab-to-tab-stop () 504 "Insert spaces or tabs to next defined tab-stop column. 505The variable `tab-stop-list' is a list of columns at which there are tab stops. 506Use \\[edit-tab-stops] to edit them interactively." 507 (interactive) 508 (and abbrev-mode (= (char-syntax (preceding-char)) ?w) 509 (expand-abbrev)) 510 (let ((tabs tab-stop-list)) 511 (while (and tabs (>= (current-column) (car tabs))) 512 (setq tabs (cdr tabs))) 513 (if tabs 514 (let ((opoint (point))) 515 (delete-horizontal-space t) 516 (indent-to (car tabs))) 517 (insert ?\s)))) 518 519(defun move-to-tab-stop () 520 "Move point to next defined tab-stop column. 521The variable `tab-stop-list' is a list of columns at which there are tab stops. 522Use \\[edit-tab-stops] to edit them interactively." 523 (interactive) 524 (let ((tabs tab-stop-list)) 525 (while (and tabs (>= (current-column) (car tabs))) 526 (setq tabs (cdr tabs))) 527 (if tabs 528 (let ((before (point))) 529 (move-to-column (car tabs) t) 530 (save-excursion 531 (goto-char before) 532 ;; If we just added a tab, or moved over one, 533 ;; delete any superfluous spaces before the old point. 534 (if (and (eq (preceding-char) ?\s) 535 (eq (following-char) ?\t)) 536 (let ((tabend (* (/ (current-column) tab-width) tab-width))) 537 (while (and (> (current-column) tabend) 538 (eq (preceding-char) ?\s)) 539 (forward-char -1)) 540 (delete-region (point) before)))))))) 541 542(define-key global-map "\t" 'indent-for-tab-command) 543(define-key esc-map "\C-\\" 'indent-region) 544(define-key ctl-x-map "\t" 'indent-rigidly) 545(define-key esc-map "i" 'tab-to-tab-stop) 546 547;;; arch-tag: f402b2a7-e44f-492f-b5b8-38996020b7c3 548;;; indent.el ends here 549