1;;; two-column.el --- minor mode for editing of two-column text
2
3;; Copyright (C) 1992, 1993, 1994, 1995, 2001, 2002, 2003, 2004,
4;;   2005, 2006, 2007 Free Software Foundation, Inc.
5
6;; Author: Daniel Pfeiffer <occitan@esperanto.org>
7;; Adapted-By: ESR, Daniel Pfeiffer
8;; Keywords: wp
9
10;; This file is part of GNU Emacs.
11
12;; Esperanto:				 English:
13
14;; ^Ci dosiero estas ero de GNU Emacs.	 This file is part of GNU Emacs.
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37;; Free Software Foundation, 51 Franklin Street, Fifth Floor
38;; Boston, MA 02110-1301, USA.
39
40;;; Commentary:
41
42;;; Komentario:				 Commentary:
43
44;; Tiu  programaro ebligas  vin redakti	 This package gives you the ability
45;; dukolumnan tekston.			 to edit text in a two-column format.
46
47
48;; Vi  havas  tri eblecojn por eki tiun	 You have three ways to start up this
49;; mal^cefan modalon.  ^Ciu donas al vi	 minor mode.  Each gives you a
50;; horizontale disigatan fenestron, si-	 horizontally split window similar to
51;; milan al fina apareco de via teksto:	 the final outcome of your text:
52
53
54;; f2 2	    asocias  novan  bufron  nomatan  associates a new  buffer called
55;; C-x 6 2  same, sed kun 2C/ anta^u.	     the   same,    but   with   2C/
56;;					     prepended.
57
58;; f2 b	    asocias alian bufron.  Vi povas  associates    another   buffer.
59;; C-x 6 b  anka^u asocii  dataron,   se vi  This can be used to associate a
60;;	    ^jus anta^ue faris C-x C-f.	     file if you just did C-x C-f.
61
62;; f2 s	    disigas  jam dukolumnan tekston  splits a  two-column  text into
63;; C-x 6 s  en  du   bufroj  ekde  la  nuna  two  buffers from  the  current
64;;	    linio,  kaj je la nuna kolumno.  line and at the current column.
65;;	    La    anta^uaj   signoj   (ofte  The preceding characters (often
66;;	    tabeligilo  a^u  |)  estas   la  tab   or  |)  are   the  column
67;;	    kolumna disiganto.  Linioj kiuj  separator.   Lines  that  don't
68;;	    ne   enhavas   ilin   ne  estas  have them  won't  be separated.
69;;	    disigitaj.   Kiel  la kvara kaj  Like the  fourth and fifth line
70;;	    la   kvina  linio se vi disigas  if  you split this  file from
71;;	    ^ci dataron ekde la unua  angla  the first english word.
72;;	    vorto.
73
74;; Se  vi  volas  meti  longajn liniojn	 If you include long lines, i.e which
75;; (ekz. programerojn) en la  kunigotan	 will span both columns  (eg.  source
76;; tekston,   ili  devas  esti  en   la	 code), they should  be  in what will
77;; estonte unua kolumno.  La alia devas	 be the    first column,    with  the
78;; havi vakajn linion apud ili.		 associated buffer having empty lines
79;;					 next to them.
80
81;; Averto: en Emacs kiam vi ^san^gas la	 Attention:  in Emacs when you change
82;; ^cefan modalon, la mal^cefaj modaloj	 the major mode,  the minor modes are
83;; estas  anka^u  elmemorigitaj.   Tiu-	 also  purged  from  memory.  In that
84;; okaze  vi devas religi la du bufrojn	 case you   must  reassociate the two
85;; per iu  C-x 6-ordono,  ekz. C-x 6 b.	 buffers with any C-x 6-command, e.g.
86;;					 C-x 6 b.
87
88;; Kiam   vi   estos  kontenta   de  la	 When you have edited both buffers to
89;; rezulto, vi kunmetos la du kolumnojn	 your  content,  you merge them  with
90;; per  C-x 6 1.   Se  vi  poste  vidas	 C-x 6 1.  If you then see a problem,
91;; problemon, vi  neniigu   la kunmeton	 you undo the  merge with  C-x u  and
92;; per C-x u  kaj  plue  modifu  la  du	 continue   to  edit the two buffers.
93;; bufrojn.  Kiam vi ne plu volas tajpi	 When you  no longer  want to edit in
94;; dukolumne,  vi  eliru el la mal^cefa	 two  columns, you turn off the minor
95;; modalo per C-x 6 d.			 mode with C-x 6 d.
96
97
98;; Aldone al dukolumna  redaktado,  ek-	 In addition to two-column editing of
99;; zemple por  skribi dulingvan tekston	 text, for example for writing a
100;; flank-al-flanke kiel ^ci tiu,  aliaj	 bilingual text side-by-side as shown
101;; interesaj uzoj trovitas por tiu mal-	 here, other interesting uses have
102;; ^cefa modalo:			 been found for this minor mode:
103
104;; Vi povas  disigi la  kolumnojn per {+} You can separate the columns with
105;; ajna   pla^ca   ^ceno   starigante {+} any string that pleases you, by
106;; `2C-separator'.   Ekzemple  "{+} " {+} setting `2C-separator'.  For example
107;; por  amuzi^gi.  f2 s  a^u  C-x 6 s {+} "{+} " if you'd like to have fun.
108;; traktas   tiujn    kun    prefiksa {+} f2 s or C-x 6 s handles these with a
109;; argumento  kiu  signifas la longon {+} prefix argument that means the
110;; de tia ^ceno.		      {+} desired length of such a string.
111
112
113;; Programistoj eble ^satus la  eblecon  Programmers might like the ability
114;; forspliti la komentarian kolumnon de  to split off the comment column of a
115;; dosiero  kiel la sekvanta.  Vi povas  file that looks like the following.
116;; rearan^gigi  la paragrafon.  La pro-  You can fill-paragraph the comment.
117;; blemo  estas  ke  koda^jo tuj   lar-  The problem is, code quickly gets
118;; ^gi^gas,  tiel  ke vi  bezonas   pli  rather wide, so you need to use a
119;; mallar^gan   komentarian   kolumnon.  narrower comment column.  Code lines
120;; Koda^jaj linioj tra `comment-column'  that reach beyond `comment-column'
121;; ne problemas,  krom  ke vi ne  vidos  are no problem, except that you
122;; iliajn finojn dum redaktado.		 won't see their end during editing.
123
124
125;; BEGIN				-- This is just some meaningless
126;;     FOR i IN 1..10 LOOP		-- code in Ada, that runs foobar
127;;	   foobar( i );			-- once for each argument from one
128;;     END LOOP;			-- to ten, and then we're already
129;; END;					-- through with it.
130
131;; Pli bone ankora^u, vi povas  pozici-	 Better yet, you can put the point
132;; i^gi anta^u "This",  tajpi  M-3 f2 s	 before "This", type  M-3 f2 s
133;; kiu  igas "-- " la separigilon inter	 which makes "-- " the separator
134;; senkomentaria  Ada  bufro  kaj  nur-	 between a no-comments Ada buffer,
135;; teksta  komentaria  bufro.   Kiam vi	 and a plain text comment buffer.
136;; denove  kuni^gos ilin,  ^ciu  nevaka	 When you put them back together,
137;; linio  de  l'  dua  kolumno   denove	 every non-empty line of the 2nd
138;; anta^uhavos "-- ".			 column will again be preceded by
139;;					 "-- ".
140
141
142;;; Code:
143
144
145;; Lucid patch
146(or (fboundp 'frame-width)
147    (fset 'frame-width 'screen-width))
148
149
150;;;;; Set up keymap ;;;;;
151
152(defvar 2C-mode-map
153  (let ((map (make-sparse-keymap)))
154    (define-key map "2" '2C-two-columns)
155    (define-key map [f2] '2C-two-columns)
156    (define-key map "b" '2C-associate-buffer)
157    (define-key map "s" '2C-split)
158    map)
159  "Keymap for commands for setting up two-column mode.")
160
161
162
163;;;###autoload (autoload '2C-command "two-column" () t 'keymap)
164(fset '2C-command 2C-mode-map)
165
166;; This one is for historical reasons and simple keyboards, it is not
167;; at all mnemonic.  All usual sequences containing 2 were used, and
168;; f2 could not be set up in a standard way under Emacs 18.
169;;;###autoload (global-set-key "\C-x6" '2C-command)
170
171;;;###autoload (global-set-key [f2] '2C-command)
172
173
174(defvar 2C-minor-mode-map
175  (let ((map (make-sparse-keymap)))
176    (define-key map "1" '2C-merge)
177    (define-key map "d" '2C-dissociate)
178    (define-key map "o" '2C-associated-buffer)
179    (define-key map "\^m" '2C-newline)
180    (define-key map "|" '2C-toggle-autoscroll)
181    (define-key map "{" '2C-shrink-window-horizontally)
182    (define-key map "}" '2C-enlarge-window-horizontally)
183    map)
184  "Keymap for commands for use in two-column mode.")
185
186
187(setq minor-mode-map-alist
188      (cons (cons '2C-mode
189		  (let ((map (make-sparse-keymap)))
190		    (substitute-key-definition '2C-command 2C-minor-mode-map
191					       map (current-global-map))
192		    (substitute-key-definition 'enlarge-window-horizontally
193					       '2C-enlarge-window-horizontally
194					       map (current-global-map))
195		    (substitute-key-definition 'shrink-window-horizontally
196					       '2C-shrink-window-horizontally
197					       map (current-global-map))
198		    map))
199	    minor-mode-map-alist))
200
201;;;;; variable declarations ;;;;;
202
203(defgroup two-column nil
204  "Minor mode for editing of two-column text."
205  :prefix "2C-"
206  :group 'frames)
207
208
209;; Markers seem to be the only buffer-id not affected by renaming a buffer.
210;; This nevertheless loses when a buffer is killed.  The variable-name is
211;; required by `describe-mode'.
212(defvar 2C-mode nil
213  "Marker to the associated buffer, if non-nil.")
214(make-variable-buffer-local '2C-mode)
215(put '2C-mode 'permanent-local t)
216
217
218
219(setq minor-mode-alist (cons '(2C-mode " 2C") minor-mode-alist))
220
221
222
223;; rearranged, so that the pertinent info will show in 40 columns
224(defcustom 2C-mode-line-format
225	'("-%*- %15b --"  (-3 . "%p")  "--%[("  mode-name
226	  minor-mode-alist  "%n"  mode-line-process  ")%]%-")
227  "*Value of `mode-line-format' for a buffer in two-column minor mode."
228  :type 'sexp
229  :group 'two-column)
230
231
232(defcustom 2C-other-buffer-hook 'text-mode
233  "*Hook run in new buffer when it is associated with current one."
234  :type 'function
235  :group 'two-column)
236
237
238(defcustom 2C-separator ""
239  "*A string inserted between the two columns when merging.
240This gets set locally by \\[2C-split]."
241  :type 'string
242  :group 'two-column)
243(put '2C-separator 'permanent-local t)
244
245
246
247(defcustom 2C-window-width 40
248  "*The width of the first column.  (Must be at least `window-min-width')
249This value is local for every buffer that sets it."
250  :type 'integer
251  :group 'two-column)
252(make-variable-buffer-local '2C-window-width)
253(put '2C-window-width 'permanent-local t)
254
255
256
257(defcustom 2C-beyond-fill-column 4
258  "*Base for calculating `fill-column' for a buffer in two-column minor mode.
259The value of `fill-column' becomes `2C-window-width' for this buffer
260minus this value."
261  :type 'integer
262  :group 'two-column)
263
264
265
266(defcustom 2C-autoscroll t
267  "If non-nil, Emacs attempts to keep the two column's buffers aligned."
268  :type 'boolean
269  :group 'two-column)
270
271
272
273(defvar 2C-autoscroll-start nil)
274(make-variable-buffer-local '2C-autoscroll-start)
275
276;;;;; base functions ;;;;;
277
278;; The access method for the other buffer.  This tries to remedy against
279;; lost local variables and lost buffers.
280(defun 2C-other (&optional req)
281  (or (if 2C-mode
282	  (or (prog1
283		  (marker-buffer 2C-mode)
284		(setq mode-line-format 2C-mode-line-format))
285	      ;; The associated buffer somehow got killed.
286	      (progn
287		;; The other variables may later be useful if the user
288		;; reestablishes the association.
289		(kill-local-variable '2C-mode)
290		(kill-local-variable 'mode-line-format)
291		nil)))
292      (if req (error "You must first set two-column minor mode"))))
293
294
295
296;; function for setting up two-column minor mode in a buffer associated
297;; with the buffer pointed to by the marker other.
298(defun 2C-mode (other)
299  "Minor mode for independently editing two columns.
300This is set up for two associated buffers by the three commands bound
301to  \\[2C-two-columns] ,  \\[2C-associate-buffer]  and  \\[2C-split].
302Turning on two-column mode calls the value of the variable `2C-mode-hook',
303if that value is non-nil.
304
305These buffers can be edited separately, for example with `fill-paragraph'.
306If you want to disable parallel scrolling temporarily, use  \\[2C-toggle-autoscroll] .
307
308If you include long lines, i.e which will span both columns (eg.
309source code), they should be in what will be the first column, with
310the associated buffer having empty lines next to them.
311
312Potential uses are writing bilingual texts, or editing the comments of a
313source code.  See the file lisp/two-column.el for detailed examples.
314
315You have the following commands at your disposal:
316
317\\[2C-two-columns]   Rearrange screen with current buffer first
318\\[2C-associate-buffer]   Reassociate buffer after changing major mode
319\\[shrink-window-horizontally], \\[enlarge-window-horizontally]   Shrink, enlarge current column
320\\[2C-associated-buffer]   Switch to associated buffer at same point
321\\[2C-newline] Insert newline(s) in both buffers at same point
322\\[2C-merge]   Merge both buffers
323\\[2C-dissociate]   Dissociate the two buffers
324
325These keybindings can be customized in your ~/.emacs by `2C-mode-map',
326`2C-minor-mode-map' and by binding `2C-command' to some prefix.
327
328The appearance of the screen can be customized by the variables
329`2C-window-width', `2C-beyond-fill-column', `2C-mode-line-format' and
330`truncate-partial-width-windows'."
331  (add-hook 'post-command-hook '2C-autoscroll nil t)
332  (setq fill-column (- 2C-window-width
333		       2C-beyond-fill-column)
334	mode-line-format 2C-mode-line-format
335	2C-mode other)
336  (run-hooks '2C-mode-hook))
337
338
339
340;;;###autoload
341(defun 2C-two-columns (&optional buffer)
342  "Split current window vertically for two-column editing.
343\\<global-map>When called the first time, associates a buffer with the current
344buffer in two-column minor mode (use \\[describe-mode] once in the mode,
345for details.).  It runs `2C-other-buffer-hook' in the new buffer.
346When called again, restores the screen layout with the current buffer
347first and the associated buffer to its right."
348  (interactive "P")
349  ;; first go to full width, so that we can certainly split into two windows
350  (if (< (window-width) (frame-width))
351      (enlarge-window 99999 t))
352  (split-window-horizontally
353   (max window-min-width (min 2C-window-width
354			      (- (frame-width) window-min-width))))
355  (if (2C-other)
356      (progn
357	(other-window 1)
358	(switch-to-buffer (2C-other))
359	(other-window -1)
360	(if 2C-autoscroll
361	    (2C-toggle-autoscroll t)))
362
363    (2C-mode (prog1 (point-marker)
364	       (other-window 1)
365	       (switch-to-buffer
366		(or buffer
367		    (generate-new-buffer (concat "2C/" (buffer-name)))))
368	       (or buffer
369		   (run-hooks '2C-other-buffer-hook))))
370
371    (2C-mode (prog1 (point-marker)
372	       (other-window -1)))))
373
374
375
376;;;###autoload
377(defun 2C-associate-buffer ()
378  "Associate another buffer with this one in two-column minor mode.
379Can also be used to associate a just previously visited file, by
380accepting the proposed default buffer.
381
382\(See  \\[describe-mode] .)"
383  (interactive)
384  (let ((b1 (current-buffer))
385	(b2 (or (2C-other)
386		(read-buffer "Associate buffer: " (other-buffer)))))
387    (save-excursion
388      (setq 2C-mode nil)
389      (set-buffer b2)
390      (and (2C-other)
391	   (not (eq b1 (2C-other)))
392	   (error "Buffer already associated with buffer `%s'"
393		  (buffer-name (2C-other))))
394      (setq b1 (and (assq '2C-window-width (buffer-local-variables))
395		    2C-window-width)))
396    ; if other buffer has a local width, adjust here too
397    (if b1 (setq 2C-window-width (- (frame-width) b1)))
398    (2C-two-columns b2)))
399
400
401
402;;;###autoload
403(defun 2C-split (arg)
404  "Split a two-column text at point, into two buffers in two-column minor mode.
405Point becomes the local value of `2C-window-width'.  Only lines that
406have the ARG same preceding characters at that column get split.  The
407ARG preceding characters without any leading whitespace become the local
408value for `2C-separator'.  This way lines that continue across both
409columns remain untouched in the first buffer.
410
411This function can be used with a prototype line, to set up things.  You
412write the first line of each column and then split that line.  E.g.:
413
414First column's text    sSs  Second column's text
415		       \\___/\\
416			/    \\
417   5 character Separator      You type  M-5 \\[2C-split]  with the point here.
418
419\(See  \\[describe-mode] .)"
420  (interactive "*p")
421  (and (2C-other)
422       (if (y-or-n-p (concat "Overwrite associated buffer `"
423			     (buffer-name (2C-other))
424			     "'? "))
425	   (save-excursion
426	     (set-buffer (2C-other))
427	     (erase-buffer))
428	 (signal 'quit nil)))
429  (let ((point (point))
430	; make next-line always come back to same column
431	(goal-column (current-column))
432	; a counter for empty lines in other buffer
433	(n (1- (count-lines (point-min) (point))))
434	chars other)
435    (save-excursion
436      (backward-char arg)
437      (setq chars (buffer-substring (point) point))
438      (skip-chars-forward " \t" point)
439      (make-local-variable '2C-separator)
440      (setq 2C-separator (buffer-substring (point) point)
441	    2C-window-width (current-column)))
442    (2C-two-columns)
443    (setq other (2C-other))
444    ; now we're ready to actually split
445    (save-excursion
446      (while (not (eobp))
447	(if (not (and (= (current-column) goal-column)
448		      (string= chars
449			       (buffer-substring (point)
450						 (save-excursion
451						   (backward-char arg)
452						   (point))))))
453	    (setq n (1+ n))
454	  (setq point (point))
455	  (backward-char arg)
456	  (skip-chars-backward " \t")
457	  (delete-region point (point))
458	  (setq point (point))
459	  (insert-char ?\n n)
460	  (append-to-buffer other point (progn (end-of-line)
461					       (if (eobp)
462						   (point)
463						 (1+ (point)))))
464	  (delete-region point (point))
465	  (setq n 0))
466	(next-line 1)))))
467
468
469
470
471(defun 2C-dissociate ()
472  "Turn off two-column minor mode in current and associated buffer.
473If the associated buffer is unmodified and empty, it is killed."
474  (interactive)
475  (let ((buffer (current-buffer)))
476    (save-excursion
477      (and (2C-other)
478	   (set-buffer (2C-other))
479	   (or (not (2C-other))
480	       (eq buffer (2C-other)))
481	   (if (and (not (buffer-modified-p))
482		    (eobp) (bobp))
483	       (kill-buffer nil)
484	     (kill-local-variable '2C-mode)
485	     (kill-local-variable '2C-window-width)
486	     (kill-local-variable '2C-separator)
487	     (kill-local-variable 'mode-line-format)
488	     (kill-local-variable 'fill-column))))
489    (kill-local-variable '2C-mode)
490    (kill-local-variable '2C-window-width)
491    (kill-local-variable '2C-separator)
492    (kill-local-variable 'mode-line-format)
493    (kill-local-variable 'fill-column)))
494
495
496
497;; this doesn't use yank-rectangle, so that the first column can
498;; contain long lines
499(defun 2C-merge ()
500  "Merges the associated buffer with the current buffer.
501They get merged at the column, which is the value of `2C-window-width',
502i.e. usually at the vertical window separator.  This separator gets
503replaced with white space.  Beyond that the value of `2C-separator' gets
504inserted on merged lines.  The two columns are thus pasted side by side,
505in a single text.  If the other buffer is not displayed to the left of
506this one, then this one becomes the left column.
507
508If you want `2C-separator' on empty lines in the second column,
509you should put just one space in them.  In the final result, you can strip
510off trailing spaces with \\[delete-trailing-whitespace]."
511  (interactive)
512  (and (> (car (window-edges)) 0)	; not touching left edge of screen
513       (eq (window-buffer (previous-window))
514	   (2C-other t))
515       (other-window -1))
516  (save-excursion
517    (let ((b1 (current-buffer))
518	  (b2 (2C-other t))
519	  string)
520      (goto-char (point-min))
521      (set-buffer b2)
522      (goto-char (point-min))
523      (while (not (eobp))
524	(setq string (buffer-substring (point)
525				       (progn (end-of-line) (point))))
526	(or (eobp)
527	    (forward-char))		; next line
528	(set-buffer b1)
529	(if (string= string "")
530	    ()
531	  (end-of-line)
532	  (indent-to-column 2C-window-width)
533	  (insert 2C-separator string))
534	(next-line 1)			; add one if necessary
535	(set-buffer b2))))
536  (if (< (window-width) (frame-width))
537      (enlarge-window 99999 t)))
538
539;;;;; utility functions ;;;;;
540
541(defun 2C-associated-buffer ()
542  "Switch to associated buffer."
543  (interactive)
544  (let ((line (+ (count-lines (point-min) (point))
545		 (if (bolp) 1 0)))
546	(col (if (eolp) (if (bolp) 0) (current-column))))
547    (if (get-buffer-window (2C-other t))
548	(select-window (get-buffer-window (2C-other)))
549      (switch-to-buffer (2C-other)))
550    (newline (goto-line line))
551    (if col
552	(move-to-column col)
553      (end-of-line 1))))
554
555(defun 2C-newline (arg)
556  "Insert ARG newlines in both buffers."
557  (interactive "P")
558  (save-window-excursion
559    (2C-associated-buffer)
560    (newline arg))
561  (newline arg))
562
563(defun 2C-toggle-autoscroll (arg)
564  "Toggle autoscrolling, or set it iff prefix ARG is non-nil and positive.
565When autoscrolling is turned on, this also realigns the two buffers."
566  (interactive "P")
567  ;(sit-for 0)
568  (setq 2C-autoscroll-start (window-start))
569  (if (setq 2C-autoscroll (if arg
570			      (>= (prefix-numeric-value arg) 0)
571			    (not 2C-autoscroll)))
572      (select-window
573       (prog1 (selected-window)
574	 (message "Autoscrolling is on.")
575	 (setq arg (count-lines (point-min) (window-start)))
576	 (if (get-buffer-window (2C-other t))
577	     (progn
578	       (select-window (get-buffer-window (2C-other)))
579	       (setq arg (- arg (count-lines (point-min) (window-start))))
580	       ;; make sure that other buffer has enough lines
581	       (save-excursion
582		 (insert-char ?\n
583			      (- arg (count-lines (window-start)
584						  (goto-char (point-max)))
585				 -1)))
586	       (scroll-up arg)))))
587    (message "Autoscrolling is off.")))
588
589
590
591(defun 2C-autoscroll ()
592  (if 2C-autoscroll
593      ;; catch a mouse scroll on non-selected scrollbar
594      (select-window
595       (prog1 (selected-window)
596	 (and (consp last-command-char)
597	      (not (eq (selected-window)
598		       (car (car (cdr last-command-char)))))
599	      (select-window (car (car (cdr last-command-char)))))
600	 ;; In some cases scrolling causes an error, but post-command-hook
601	 ;; shouldn't, and should always stay in the original window
602	 (condition-case ()
603	     (and (or 2C-autoscroll-start (2C-toggle-autoscroll t) nil)
604		  (/= (window-start) 2C-autoscroll-start)
605		  (2C-other)
606		  (get-buffer-window (2C-other))
607		  (let ((lines (count-lines (window-start)
608					    2C-autoscroll-start)))
609		    (if (< (window-start) 2C-autoscroll-start)
610			(setq lines (- lines)))
611		    (setq 2C-autoscroll-start (window-start))
612		    (select-window (get-buffer-window (2C-other)))
613		    ;; make sure that other buffer has enough lines
614		    (save-excursion
615		      (insert-char
616		       ?\n (- lines (count-lines (window-start)
617						 (goto-char (point-max)))
618			      -1)))
619		    (scroll-up lines)
620		    (setq 2C-autoscroll-start (window-start))))
621	   (error))))))
622
623
624
625(defun 2C-enlarge-window-horizontally (arg)
626  "Make current window ARG columns wider."
627  (interactive "p")
628  (enlarge-window arg t)
629  (and (2C-other)
630       (setq 2C-window-width (+ 2C-window-width arg))
631       (set-buffer (2C-other))
632       (setq 2C-window-width (- 2C-window-width arg))))
633
634(defun 2C-shrink-window-horizontally (arg)
635  "Make current window ARG columns narrower."
636  (interactive "p")
637  (2C-enlarge-window-horizontally (- arg)))
638
639
640
641(provide 'two-column)
642
643;;; arch-tag: 2021b5ab-d3a4-4a8c-a21c-1936b0f9e6b1
644;;; two-column.el ends here
645