emacs / lisp / indent.el

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
;;; indent.el --- indentation commands for Emacs

;; Copyright (C) 1985, 1995 Free Software Foundation, Inc.

;; Maintainer: FSF

;; This file is part of GNU Emacs.

;; GNU Emacs is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation; either version 2, or (at your option)
;; any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs; see the file COPYING.  If not, write to the
;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
;; Boston, MA 02111-1307, USA.

;;; Commentary:

;; Commands for making and changing indentation in text.  These are
;; described in the Emacs manual.

;;; Code:

(defgroup indent nil
  "Indentation commands"
  :group 'editing)

(defcustom standard-indent 4
  "*Default number of columns for margin-changing functions to indent."
  :group 'indent
  :type 'integer)

(defvar indent-line-function 'indent-to-left-margin
  "Function to indent current line.")

(defun indent-according-to-mode ()
  "Indent line in proper way for current major mode."
  (interactive)
  (funcall indent-line-function))

(defun indent-for-tab-command (&optional prefix-arg)
  "Indent line in proper way for current major mode."
  (interactive "P")
  (if (eq indent-line-function 'indent-to-left-margin)
      (insert-tab prefix-arg)
    (if prefix-arg
	(funcall indent-line-function prefix-arg)
      (funcall indent-line-function))))

(defun insert-tab (&optional prefix-arg)
  (let ((count (prefix-numeric-value prefix-arg)))
    (if (and abbrev-mode
	     (eq (char-syntax (preceding-char)) ?w))
	(expand-abbrev))
    (if indent-tabs-mode
	(insert-char ?\t count)
      (indent-to (* tab-width (+ count (/ (current-column) tab-width)))))))

(defun indent-rigidly (start end arg)
  "Indent all lines starting in the region sideways by ARG columns.
Called from a program, takes three arguments, START, END and ARG."
  (interactive "r\np")
  (save-excursion
    (goto-char end)
    (setq end (point-marker))
    (goto-char start)
    (or (bolp) (forward-line 1))
    (while (< (point) end)
      (let ((indent (current-indentation))
	    eol-flag)
	(save-excursion
	  (skip-chars-forward " \t")
	  (setq eol-flag (eolp)))
	(or eol-flag
	    (indent-to (max 0 (+ indent arg)) 0))
	(delete-region (point) (progn (skip-chars-forward " \t") (point))))
      (forward-line 1))
    (move-marker end nil)))

(defun indent-line-to (column)
  "Indent current line to COLUMN.
This function removes or adds spaces and tabs at beginning of line
only if necessary.  It leaves point at end of indentation."
  (back-to-indentation)
  (let ((cur-col (current-column)))
    (cond ((< cur-col column)
	   (if (>= (- column (* (/ cur-col tab-width) tab-width)) tab-width)
	       (delete-region (point)
			      (progn (skip-chars-backward " ") (point))))
	   (indent-to column))
	  ((> cur-col column) ; too far right (after tab?)
	   (delete-region (progn (move-to-column column t) (point))
			  (progn (back-to-indentation) (point)))))))

(defun current-left-margin ()
  "Return the left margin to use for this line.
This is the value of the buffer-local variable `left-margin' plus the value
of the `left-margin' text-property at the start of the line."
  (save-excursion
    (back-to-indentation)
    (max 0
	 (+ left-margin (or (get-text-property
			     (if (and (eobp) (not (bobp)))
				 (1- (point)) (point))
			     'left-margin) 0)))))

(defun move-to-left-margin (&optional n force)
  "Move to the left margin of the current line.
With optional argument, move forward N-1 lines first.
The column moved to is the one given by the `current-left-margin' function.
If the line's indentation appears to be wrong, and this command is called
interactively or with optional argument FORCE, it will be fixed."
  (interactive (list (prefix-numeric-value current-prefix-arg) t))
  (beginning-of-line n)
  (skip-chars-forward " \t")
  (let ((lm (current-left-margin))
	(cc (current-column)))
    (cond ((> cc lm)
	   (if (> (move-to-column lm force) lm)
	       ;; If lm is in a tab and we are not forcing, move before tab
	       (backward-char 1)))
	  ((and force (< cc lm))
	   (indent-to-left-margin)))))

;; This is the default indent-line-function,
;; used in Fundamental Mode, Text Mode, etc.
(defun indent-to-left-margin ()
  "Indent current line to the column given by `current-left-margin'."
  (indent-line-to (current-left-margin)))

(defun delete-to-left-margin (&optional from to)
  "Remove left margin indentation from a region.
This deletes to the column given by `current-left-margin'.
In no case will it delete non-whitespace.
Args FROM and TO are optional; default is the whole buffer."
  (save-excursion
    (goto-char (or to (point-max)))
    (setq to (point-marker))
    (goto-char (or from (point-min)))
    (or (bolp) (forward-line 1))
    (while (< (point) to)
      (delete-region (point) (progn (move-to-left-margin nil t) (point)))
      (forward-line 1))
    (move-marker to nil)))

(defun set-left-margin (from to lm)
  "Set the left margin of the region to WIDTH.
If `auto-fill-mode' is active, re-fill the region to fit the new margin."
  (interactive "r\nNSet left margin to column: ")
  (if (interactive-p) (setq lm (prefix-numeric-value lm)))
  (save-excursion
    ;; If inside indentation, start from BOL.
    (goto-char from)
    (skip-chars-backward " \t")
    (if (bolp) (setq from (point)))
    ;; Place end after whitespace
    (goto-char to)
    (skip-chars-forward " \t")
    (setq to (point-marker)))
  ;; Delete margin indentation first, but keep paragraph indentation.
  (delete-to-left-margin from to)
  (put-text-property from to 'left-margin lm)
  (indent-rigidly from to lm)
  (if auto-fill-function (save-excursion (fill-region from to nil t t)))
  (move-marker to nil))

(defun set-right-margin (from to lm)
  "Set the right margin of the region to WIDTH.
If `auto-fill-mode' is active, re-fill the region to fit the new margin."
  (interactive "r\nNSet right margin to width: ")
  (if (interactive-p) (setq lm (prefix-numeric-value lm)))
  (save-excursion
    (goto-char from)
    (skip-chars-backward " \t")
    (if (bolp) (setq from (point))))
  (put-text-property from to 'right-margin lm)
  (if auto-fill-function (save-excursion (fill-region from to nil t t))))

(defun alter-text-property (from to prop func &optional object)
  "Programmatically change value of a text-property.
For each region between FROM and TO that has a single value for PROPERTY,
apply FUNCTION to that value and sets the property to the function's result.
Optional fifth argument OBJECT specifies the string or buffer to operate on."
  (let ((begin from)
	end val)
    (while (setq val (get-text-property begin prop object)
		 end (text-property-not-all begin to prop val object))
      (put-text-property begin end prop (funcall func val) object)
      (setq begin end))
    (if (< begin to)
	(put-text-property begin to prop (funcall func val) object))))

(defun increase-left-margin (from to inc)
  "Increase or decrease the left-margin of the region.
With no prefix argument, this adds `standard-indent' of indentation.
A prefix arg (optional third arg INC noninteractively) specifies the amount
to change the margin by, in characters.
If `auto-fill-mode' is active, re-fill the region to fit the new margin."
  (interactive "*r\nP")
  (setq inc (if inc (prefix-numeric-value inc) standard-indent))
  (save-excursion
    (goto-char from)
    (skip-chars-backward " \t")
    (if (bolp) (setq from (point)))
    (goto-char to)
    (setq to (point-marker)))
  (alter-text-property from to 'left-margin
		       (lambda (v) (max (- left-margin) (+ inc (or v 0)))))
  (indent-rigidly from to inc)
  (if auto-fill-function (save-excursion (fill-region from to nil t t)))
  (move-marker to nil))

(defun decrease-left-margin (from to inc)
  "Make the left margin of the region smaller.
With no prefix argument, decrease the indentation by `standard-indent'.
A prefix arg (optional third arg INC noninteractively) specifies the amount
to change the margin by, in characters.
If `auto-fill-mode' is active, re-fill the region to fit the new margin."
  (interactive "*r\nP")
  (setq inc (if inc (prefix-numeric-value inc) standard-indent))
  (increase-left-margin from to (- inc)))

(defun increase-right-margin (from to inc)
  "Increase the right-margin of the region.
With no prefix argument, increase the right margin by `standard-indent'.
A prefix arg (optional third arg INC noninteractively) specifies the amount
to change the margin by, in characters.  A negative argument decreases
the right margin width.
If `auto-fill-mode' is active, re-fill the region to fit the new margin."
  (interactive "r\nP")
  (if (interactive-p)
      (setq inc (if inc (prefix-numeric-value current-prefix-arg)
		  standard-indent)))
  (save-excursion
    (alter-text-property from to 'right-margin
       (lambda (v) (+ inc (or v 0))))
    (if auto-fill-function
	(fill-region from to nil t t))))

(defun decrease-right-margin (from to inc)
  "Make the right margin of the region smaller.
With no prefix argument, decrease the right margin by `standard-indent'.
A prefix arg (optional third arg INC noninteractively) specifies the amount
of width to remove, in characters.  A negative argument increases
the right margin width.
If `auto-fill-mode' is active, re-fills region to fit in new margin."
  (interactive "*r\nP")
  (setq inc (if inc (prefix-numeric-value inc) standard-indent))
  (increase-right-margin from to (- inc)))

(defun beginning-of-line-text (&optional n)
  "Move to the beginning of the text on this line.
With optional argument, move forward N-1 lines first.
From the beginning of the line, moves past the left-margin indentation, the
fill-prefix, and any indentation used for centering or right-justifying the
line, but does not move past any whitespace that was explicitly inserted 
\(such as a tab used to indent the first line of a paragraph)."
  (interactive "p")
  (beginning-of-line n)
  (skip-chars-forward " \t")
  ;; Skip over fill-prefix.
  (if (and fill-prefix 
	   (not (string-equal fill-prefix "")))
      (if (equal fill-prefix
		 (buffer-substring 
		  (point) (min (point-max) (+ (length fill-prefix) (point)))))
	  (forward-char (length fill-prefix)))
    (if (and adaptive-fill-mode adaptive-fill-regexp
	     (looking-at adaptive-fill-regexp))
	(goto-char (match-end 0))))
  ;; Skip centering or flushright indentation
  (if (memq (current-justification) '(center right))
      (skip-chars-forward " \t")))

(defvar indent-region-function nil
  "Short cut function to indent region using `indent-according-to-mode'.
A value of nil means really run `indent-according-to-mode' on each line.")

(defun indent-region (start end column)
  "Indent each nonblank line in the region.
With no argument, indent each line using `indent-according-to-mode',
or use `indent-region-function' to do the whole region if that's non-nil.
If there is a fill prefix, make each line start with the fill prefix.
With argument COLUMN, indent each line to that column.
Called from a program, takes three args: START, END and COLUMN."
  (interactive "r\nP")
  (if (null column)
      (if fill-prefix
	  (save-excursion
	    (goto-char end)
	    (setq end (point-marker))
	    (goto-char start)
	    (let ((regexp (regexp-quote fill-prefix)))
	      (while (< (point) end)
		(or (looking-at regexp)
		    (and (bolp) (eolp))
		    (insert fill-prefix))
		(forward-line 1))))
	(if indent-region-function
	    (funcall indent-region-function start end)
	  (save-excursion
	    (goto-char end)
	    (setq end (point-marker))
	    (goto-char start)
	    (or (bolp) (forward-line 1))
	    (while (< (point) end)
	      (or (and (bolp) (eolp))
		  (funcall indent-line-function))
	      (forward-line 1))
	    (move-marker end nil))))
    (setq column (prefix-numeric-value column))
    (save-excursion
      (goto-char end)
      (setq end (point-marker))
      (goto-char start)
      (or (bolp) (forward-line 1))
      (while (< (point) end)
	(delete-region (point) (progn (skip-chars-forward " \t") (point)))
	(or (eolp)
	    (indent-to column 0))
	(forward-line 1))
      (move-marker end nil))))

(defun indent-relative-maybe ()
  "Indent a new line like previous nonblank line."
  (interactive)
  (indent-relative t))

(defun indent-relative (&optional unindented-ok)
  "Space out to under next indent point in previous nonblank line.
An indent point is a non-whitespace character following whitespace.
If the previous nonblank line has no indent points beyond the
column point starts at, `tab-to-tab-stop' is done instead."
  (interactive "P")
  (if (and abbrev-mode
	   (eq (char-syntax (preceding-char)) ?w))
      (expand-abbrev))
  (let ((start-column (current-column))
	indent)
    (save-excursion
      (beginning-of-line)
      (if (re-search-backward "^[^\n]" nil t)
	  (let ((end (save-excursion (forward-line 1) (point))))
	    (move-to-column start-column)
	    ;; Is start-column inside a tab on this line?
	    (if (> (current-column) start-column)
		(backward-char 1))
	    (or (looking-at "[ \t]")
		unindented-ok
		(skip-chars-forward "^ \t" end))
	    (skip-chars-forward " \t" end)
	    (or (= (point) end) (setq indent (current-column))))))
    (if indent
	(let ((opoint (point-marker)))
	  (delete-region (point) (progn (skip-chars-backward " \t") (point)))
	  (indent-to indent 0)
	  (if (> opoint (point))
	      (goto-char opoint))
	  (move-marker opoint nil))
      (tab-to-tab-stop))))

(defcustom tab-stop-list
  '(8 16 24 32 40 48 56 64 72 80 88 96 104 112 120)
  "*List of tab stop positions used by `tab-to-tab-stop'.
This should be a list of integers, ordered from smallest to largest."
  :group 'indent
  :type '(repeat integer))

(defvar edit-tab-stops-map nil "Keymap used in `edit-tab-stops'.")
(if edit-tab-stops-map
    nil
  (setq edit-tab-stops-map (make-sparse-keymap))
  (define-key edit-tab-stops-map "\C-x\C-s" 'edit-tab-stops-note-changes)
  (define-key edit-tab-stops-map "\C-c\C-c" 'edit-tab-stops-note-changes))

(defvar edit-tab-stops-buffer nil
  "Buffer whose tab stops are being edited--in case
the variable `tab-stop-list' is local in that buffer.")

(defun edit-tab-stops ()
  "Edit the tab stops used by `tab-to-tab-stop'.
Creates a buffer *Tab Stops* containing text describing the tab stops.
A colon indicates a column where there is a tab stop.
You can add or remove colons and then do \\<edit-tab-stops-map>\\[edit-tab-stops-note-changes] to make changes take effect."
  (interactive)
  (setq edit-tab-stops-buffer (current-buffer))
  (switch-to-buffer (get-buffer-create "*Tab Stops*"))
  (use-local-map edit-tab-stops-map)
  (make-local-variable 'indent-tabs-mode)
  (setq indent-tabs-mode nil)
  (overwrite-mode 1)
  (setq truncate-lines t)
  (erase-buffer)
  (let ((tabs tab-stop-list))
    (while tabs
      (indent-to (car tabs) 0)
      (insert ?:)
      (setq tabs (cdr tabs))))
  (let ((count 0))
    (insert ?\n)
    (while (< count 8)
      (insert (+ count ?0))
    (insert "         ")
      (setq count (1+ count)))
    (insert ?\n)
    (while (> count 0)
      (insert "0123456789")
      (setq count (1- count))))
  (insert "\nTo install changes, type C-c C-c")
  (goto-char (point-min)))

(defun edit-tab-stops-note-changes ()
  "Put edited tab stops into effect."
  (interactive)
    (let (tabs)
      (save-excursion
	(goto-char 1)
	(end-of-line)
	(while (search-backward ":" nil t)
	  (setq tabs (cons (current-column) tabs))))
      (bury-buffer (prog1 (current-buffer)
			  (switch-to-buffer edit-tab-stops-buffer)))
      (setq tab-stop-list tabs))
  (message "Tab stops installed"))

(defun tab-to-tab-stop ()
  "Insert spaces or tabs to next defined tab-stop column.
The variable `tab-stop-list' is a list of columns at which there are tab stops.
Use \\[edit-tab-stops] to edit them interactively."
  (interactive)
  (and abbrev-mode (= (char-syntax (preceding-char)) ?w)
       (expand-abbrev))
  (let ((tabs tab-stop-list))
    (while (and tabs (>= (current-column) (car tabs)))
      (setq tabs (cdr tabs)))
    (if tabs
	(let ((opoint (point)))
	  (skip-chars-backward " \t")
	  (delete-region (point) opoint)
	  (indent-to (car tabs)))
      (insert ?\ ))))

(defun move-to-tab-stop ()
  "Move point to next defined tab-stop column.
The variable `tab-stop-list' is a list of columns at which there are tab stops.
Use \\[edit-tab-stops] to edit them interactively."
  (interactive)
  (let ((tabs tab-stop-list))
    (while (and tabs (>= (current-column) (car tabs)))
      (setq tabs (cdr tabs)))
    (if tabs
	(let ((before (point)))
	  (move-to-column (car tabs) t)
	  (save-excursion
	    (goto-char before)
	    ;; If we just added a tab, or moved over one,
	    ;; delete any superfluous spaces before the old point.
	    (if (and (eq (preceding-char) ?\ )
		     (eq (following-char) ?\t))
		(let ((tabend (* (/ (current-column) tab-width) tab-width)))
		  (while (and (> (current-column) tabend)
			      (eq (preceding-char) ?\ ))
		    (forward-char -1))
		  (delete-region (point) before))))))))

(define-key global-map "\t" 'indent-for-tab-command)
(define-key esc-map "\034" 'indent-region)
(define-key ctl-x-map "\t" 'indent-rigidly)
(define-key esc-map "i" 'tab-to-tab-stop)

;;; indent.el ends here
Tip: Filter by directory path e.g. /media app.js to search for public/media/app.js.
Tip: Use camelCasing e.g. ProjME to search for ProjectModifiedEvent.java.
Tip: Filter by extension type e.g. /repo .js to search for all .js files in the /repo directory.
Tip: Separate your search with spaces e.g. /ssh pom.xml to search for src/ssh/pom.xml.
Tip: Use ↑ and ↓ arrow keys to navigate and return to view the file.
Tip: You can also navigate files with Ctrl+j (next) and Ctrl+k (previous) and view the file with Ctrl+o.
Tip: You can also navigate files with Alt+j (next) and Alt+k (previous) and view the file with Alt+o.