lisp/sort.el

   1 ;;; sort.el --- commands to sort text in an Emacs buffer
   2
   3 ;; Copyright (C) 1986, 1987, 1994, 1995, 2002, 2003,
   4 ;;   2004, 2005, 2006 Free Software Foundation, Inc.
   5
   6 ;; Author: Howie Kaye
   7 ;; Maintainer: FSF
   8 ;; Keywords: unix
   9
  10 ;; This file is part of GNU Emacs.
  11
  12 ;; GNU Emacs is free software; you can redistribute it and/or modify
  13 ;; it under the terms of the GNU General Public License as published by
  14 ;; the Free Software Foundation; either version 2, or (at your option)
  15 ;; any later version.
  16
  17 ;; GNU Emacs is distributed in the hope that it will be useful,
  18 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 ;; GNU General Public License for more details.
  21
  22 ;; You should have received a copy of the GNU General Public License
  23 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  24 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  25 ;; Boston, MA 02110-1301, USA.
  26
  27 ;;; Commentary:
  28
  29 ;; This package provides the sorting facilities documented in the Emacs
  30 ;; user's manual.
  31
  32 ;;; Code:
  33
  34 (defgroup sort nil
  35   "Commands to sort text in an Emacs buffer."
  36   :group 'data)
  37
  38 (defcustom sort-fold-case nil
  39   "*Non-nil if the buffer sort functions should ignore case."
  40   :group 'sort
  41   :type 'boolean)
  42
  43 ;;;###autoload
  44 (defun sort-subr (reverse nextrecfun endrecfun
  45                           &optional startkeyfun endkeyfun predicate)
  46   "General text sorting routine to divide buffer into records and sort them.
  47
  48 We divide the accessible portion of the buffer into disjoint pieces
  49 called sort records.  A portion of each sort record (perhaps all of
  50 it) is designated as the sort key.  The records are rearranged in the
  51 buffer in order by their sort keys.  The records may or may not be
  52 contiguous.
  53
  54 Usually the records are rearranged in order of ascending sort key.
  55 If REVERSE is non-nil, they are rearranged in order of descending sort key.
  56 The variable `sort-fold-case' determines whether alphabetic case affects
  57 the sort order.
  58
  59 The next four arguments are functions to be called to move point
  60 across a sort record.  They will be called many times from within sort-subr.
  61
  62 NEXTRECFUN is called with point at the end of the previous record.
  63 It moves point to the start of the next record.
  64 It should move point to the end of the buffer if there are no more records.
  65 The first record is assumed to start at the position of point when sort-subr
  66 is called.
  67
  68 ENDRECFUN is called with point within the record.
  69 It should move point to the end of the record.
  70
  71 STARTKEYFUN moves from the start of the record to the start of the key.
  72 It may return either a non-nil value to be used as the key, or
  73 else the key is the substring between the values of point after
  74 STARTKEYFUN and ENDKEYFUN are called.  If STARTKEYFUN is nil, the key
  75 starts at the beginning of the record.
  76
  77 ENDKEYFUN moves from the start of the sort key to the end of the sort key.
  78 ENDKEYFUN may be nil if STARTKEYFUN returns a value or if it would be the
  79 same as ENDRECFUN.
  80
  81 PREDICATE is the function to use to compare keys.  If keys are numbers,
  82 it defaults to `<', otherwise it defaults to `string<'."
  83   ;; Heuristically try to avoid messages if sorting a small amt of text.
  84   (let ((messages (> (- (point-max) (point-min)) 50000)))
  85     (save-excursion
  86       (if messages (message "Finding sort keys..."))
  87       (let* ((sort-lists (sort-build-lists nextrecfun endrecfun
  88                                            startkeyfun endkeyfun))
  89              (old (reverse sort-lists))
  90              (case-fold-search sort-fold-case))
  91         (if (null sort-lists)
  92             ()
  93           (or reverse (setq sort-lists (nreverse sort-lists)))
  94           (if messages (message "Sorting records..."))
  95           (setq sort-lists
  96                 (sort sort-lists
  97                       (cond (predicate
  98                              `(lambda (a b) (,predicate (car a) (car b))))
  99                             ((numberp (car (car sort-lists)))
 100                              'car-less-than-car)
 101                             ((consp (car (car sort-lists)))
 102                              (lambda (a b)
 103                                (> 0 (compare-buffer-substrings
 104                                      nil (car (car a)) (cdr (car a))
 105                                      nil (car (car b)) (cdr (car b))))))
 106                             (t
 107                              (lambda (a b) (string< (car a) (car b)))))))
 108           (if reverse (setq sort-lists (nreverse sort-lists)))
 109           (if messages (message "Reordering buffer..."))
 110           (sort-reorder-buffer sort-lists old)))
 111       (if messages (message "Reordering buffer... Done"))))
 112   nil)
 113
 114 ;; Parse buffer into records using the arguments as Lisp expressions;
 115 ;; return a list of records.  Each record looks like (KEY STARTPOS . ENDPOS)
 116 ;; where KEY is the sort key (a number or string),
 117 ;; and STARTPOS and ENDPOS are the bounds of this record in the buffer.
 118
 119 ;; The records appear in the list lastmost first!
 120
 121 (defun sort-build-lists (nextrecfun endrecfun startkeyfun endkeyfun)
 122   (let ((sort-lists ())
 123         (start-rec nil)
 124         done key)
 125     ;; Loop over sort records.
 126     ;(goto-char (point-min)) -- it is the caller's responsibility to
 127     ;arrange this if necessary
 128     (while (not (eobp))
 129       (setq start-rec (point))          ;save record start
 130       (setq done nil)
 131       ;; Get key value, or move to start of key.
 132       (setq key (catch 'key
 133                   (or (and startkeyfun (funcall startkeyfun))
 134                       ;; If key was not returned as value,
 135                       ;; move to end of key and get key from the buffer.
 136                       (let ((start (point)))
 137                         (funcall (or endkeyfun
 138                                      (prog1 endrecfun (setq done t))))
 139                         (cons start (point))))))
 140       ;; Move to end of this record (start of next one, or end of buffer).
 141       (cond ((prog1 done (setq done nil)))
 142             (endrecfun (funcall endrecfun))
 143             (nextrecfun (funcall nextrecfun) (setq done t)))
 144       (if key (push
 145                ;; consing optimization in case in which key is same as record.
 146                (if (and (consp key)
 147                         (equal (car key) start-rec)
 148                         (equal (cdr key) (point)))
 149                    (cons key key)
 150                  (cons key (cons start-rec (point))))
 151                sort-lists))
 152       (and (not done) nextrecfun (funcall nextrecfun)))
 153     sort-lists))
 154
 155 (defun sort-reorder-buffer (sort-lists old)
 156   (let ((last (point-min))
 157         (min (point-min)) (max (point-max))
 158         (old-buffer (current-buffer))
 159         temp-buffer)
 160     (with-temp-buffer
 161       ;; Record the temporary buffer.
 162       (setq temp-buffer (current-buffer))
 163
 164       ;; Copy the sorted text into the temporary buffer.
 165       (while sort-lists
 166         (goto-char (point-max))
 167         (insert-buffer-substring old-buffer
 168                                  last
 169                                  (nth 1 (car old)))
 170         (goto-char (point-max))
 171         (insert-buffer-substring old-buffer
 172                                  (nth 1 (car sort-lists))
 173                                  (cdr (cdr (car sort-lists))))
 174         (setq last (cdr (cdr (car old)))
 175               sort-lists (cdr sort-lists)
 176               old (cdr old)))
 177       (goto-char (point-max))
 178       (insert-buffer-substring old-buffer last max)
 179
 180       ;; Copy the reordered text from the temporary buffer
 181       ;; to the buffer we sorted (OLD-BUFFER).
 182       (set-buffer old-buffer)
 183       (let ((inhibit-quit t))
 184         ;; Make sure insertions done for reordering
 185         ;; saves any markers at the end of the sorted region,
 186         ;; by leaving the last character of the region.
 187         (delete-region min (1- max))
 188         ;; Now replace the one remaining old character with the sorted text.
 189         (goto-char (point-min))
 190         (insert-buffer-substring temp-buffer)
 191         (delete-region max (1+ max))))))
 192
 193 ;;;###autoload
 194 (defun sort-lines (reverse beg end)
 195   "Sort lines in region alphabetically; argument means descending order.
 196 Called from a program, there are three arguments:
 197 REVERSE (non-nil means reverse order), BEG and END (region to sort).
 198 The variable `sort-fold-case' determines whether alphabetic case affects
 199 the sort order."
 200   (interactive "P\nr")
 201   (save-excursion
 202     (save-restriction
 203       (narrow-to-region beg end)
 204       (goto-char (point-min))
 205       (sort-subr reverse 'forward-line 'end-of-line))))
 206
 207 ;;;###autoload
 208 (defun sort-paragraphs (reverse beg end)
 209   "Sort paragraphs in region alphabetically; argument means descending order.
 210 Called from a program, there are three arguments:
 211 REVERSE (non-nil means reverse order), BEG and END (region to sort).
 212 The variable `sort-fold-case' determines whether alphabetic case affects
 213 the sort order."
 214   (interactive "P\nr")
 215   (save-excursion
 216     (save-restriction
 217       (narrow-to-region beg end)
 218       (goto-char (point-min))
 219       (sort-subr reverse
 220                  (function
 221                   (lambda ()
 222                     (while (and (not (eobp)) (looking-at paragraph-separate))
 223                       (forward-line 1))))
 224                  'forward-paragraph))))
 225
 226 ;;;###autoload
 227 (defun sort-pages (reverse beg end)
 228   "Sort pages in region alphabetically; argument means descending order.
 229 Called from a program, there are three arguments:
 230 REVERSE (non-nil means reverse order), BEG and END (region to sort).
 231 The variable `sort-fold-case' determines whether alphabetic case affects
 232 the sort order."
 233   (interactive "P\nr")
 234   (save-excursion
 235     (save-restriction
 236       (narrow-to-region beg end)
 237       (goto-char (point-min))
 238       (sort-subr reverse
 239                  (function (lambda () (skip-chars-forward "\n")))
 240                  'forward-page))))
 241 \f
 242 (defvar sort-fields-syntax-table nil)
 243 (if sort-fields-syntax-table nil
 244   (let ((table (make-syntax-table))
 245         (i 0))
 246     (while (< i 256)
 247       (modify-syntax-entry i "w" table)
 248       (setq i (1+ i)))
 249     (modify-syntax-entry ?\  " " table)
 250     (modify-syntax-entry ?\t " " table)
 251     (modify-syntax-entry ?\n " " table)
 252     (modify-syntax-entry ?\. "_" table) ; for floating pt. numbers. -wsr
 253     (setq sort-fields-syntax-table table)))
 254
 255 (defcustom sort-numeric-base 10
 256   "*The default base used by `sort-numeric-fields'."
 257   :group 'sort
 258   :type 'integer)
 259
 260 ;;;###autoload
 261 (defun sort-numeric-fields (field beg end)
 262   "Sort lines in region numerically by the ARGth field of each line.
 263 Fields are separated by whitespace and numbered from 1 up.
 264 Specified field must contain a number in each line of the region,
 265 which may begin with \"0x\" or \"0\" for hexadecimal and octal values.
 266 Otherwise, the number is interpreted according to sort-numeric-base.
 267 With a negative arg, sorts by the ARGth field counted from the right.
 268 Called from a program, there are three arguments:
 269 FIELD, BEG and END.  BEG and END specify region to sort."
 270   (interactive "p\nr")
 271   (sort-fields-1 field beg end
 272                  (lambda ()
 273                    (sort-skip-fields field)
 274                    (let* ((case-fold-search t)
 275                           (base
 276                            (if (looking-at "\\(0x\\)[0-9a-f]\\|\\(0\\)[0-7]")
 277                                (cond ((match-beginning 1)
 278                                       (goto-char (match-end 1))
 279                                       16)
 280                                      ((match-beginning 2)
 281                                       (goto-char (match-end 2))
 282                                       8)
 283                                      (t nil)))))
 284                      (string-to-number (buffer-substring (point)
 285                                                          (save-excursion
 286                                                            (forward-sexp 1)
 287                                                            (point)))
 288                                        (or base sort-numeric-base))))
 289                  nil))
 290
 291 ;;;;;###autoload
 292 ;;(defun sort-float-fields (field beg end)
 293 ;;  "Sort lines in region numerically by the ARGth field of each line.
 294 ;;Fields are separated by whitespace and numbered from 1 up.  Specified field
 295 ;;must contain a floating point number in each line of the region.  With a
 296 ;;negative arg, sorts by the ARGth field counted from the right.  Called from a
 297 ;;program, there are three arguments: FIELD, BEG and END.  BEG and END specify
 298 ;;region to sort."
 299 ;;  (interactive "p\nr")
 300 ;;  (sort-fields-1 field beg end
 301 ;;               (function (lambda ()
 302 ;;                           (sort-skip-fields field)
 303 ;;                           (string-to-number
 304 ;;                            (buffer-substring
 305 ;;                             (point)
 306 ;;                             (save-excursion
 307 ;;                               (re-search-forward
 308 ;;                                "[+-]?[0-9]*\.?[0-9]*\\([eE][+-]?[0-9]+\\)?")
 309 ;;                               (point))))))
 310 ;;               nil))
 311
 312 ;;;###autoload
 313 (defun sort-fields (field beg end)
 314   "Sort lines in region lexicographically by the ARGth field of each line.
 315 Fields are separated by whitespace and numbered from 1 up.
 316 With a negative arg, sorts by the ARGth field counted from the right.
 317 Called from a program, there are three arguments:
 318 FIELD, BEG and END.  BEG and END specify region to sort.
 319 The variable `sort-fold-case' determines whether alphabetic case affects
 320 the sort order."
 321   (interactive "p\nr")
 322   (sort-fields-1 field beg end
 323                  (function (lambda ()
 324                              (sort-skip-fields field)
 325                              nil))
 326                  (function (lambda () (skip-chars-forward "^ \t\n")))))
 327
 328 (defun sort-fields-1 (field beg end startkeyfun endkeyfun)
 329   (let ((tbl (syntax-table)))
 330     (if (zerop field) (setq field 1))
 331     (unwind-protect
 332         (save-excursion
 333           (save-restriction
 334             (narrow-to-region beg end)
 335             (goto-char (point-min))
 336             (set-syntax-table sort-fields-syntax-table)
 337             (sort-subr nil
 338                        'forward-line 'end-of-line
 339                        startkeyfun endkeyfun)))
 340       (set-syntax-table tbl))))
 341
 342 ;; Position at the beginning of field N on the current line,
 343 ;; assuming point is initially at the beginning of the line.
 344 (defun sort-skip-fields (n)
 345   (if (> n 0)
 346       ;; Skip across N - 1 fields.
 347       (let ((i (1- n)))
 348         (while (> i 0)
 349           (skip-chars-forward " \t")
 350           (skip-chars-forward "^ \t\n")
 351           (setq i (1- i)))
 352         (skip-chars-forward " \t")
 353         (if (eolp)
 354             (error "Line has too few fields: %s"
 355                    (buffer-substring
 356                     (save-excursion (beginning-of-line) (point))
 357                     (save-excursion (end-of-line) (point))))))
 358     (end-of-line)
 359     ;; Skip back across - N - 1 fields.
 360     (let ((i (1- (- n))))
 361       (while (> i 0)
 362         (skip-chars-backward " \t")
 363         (skip-chars-backward "^ \t\n")
 364         (setq i (1- i)))
 365       (skip-chars-backward " \t"))
 366     (if (bolp)
 367         (error "Line has too few fields: %s"
 368                (buffer-substring
 369                 (save-excursion (beginning-of-line) (point))
 370                 (save-excursion (end-of-line) (point)))))
 371     ;; Position at the front of the field
 372     ;; even if moving backwards.
 373     (skip-chars-backward "^ \t\n")))
 374 \f
 375 (defvar sort-regexp-fields-regexp)
 376 (defvar sort-regexp-record-end)
 377
 378 ;; Move to the beginning of the next match for record-regexp,
 379 ;; and set sort-regexp-record-end to the end of that match.
 380 ;; If the next match is empty and does not advance point,
 381 ;; skip one character and try again.
 382 (defun sort-regexp-fields-next-record ()
 383   (let ((oldpos (point)))
 384     (and (re-search-forward sort-regexp-fields-regexp nil 'move)
 385          (setq sort-regexp-record-end (match-end 0))
 386          (if (= sort-regexp-record-end oldpos)
 387              (progn
 388                (forward-char 1)
 389                (re-search-forward sort-regexp-fields-regexp nil 'move)
 390                (setq sort-regexp-record-end (match-end 0)))
 391            t)
 392          (goto-char (match-beginning 0)))))
 393
 394 ;;;###autoload
 395 (defun sort-regexp-fields (reverse record-regexp key-regexp beg end)
 396   "Sort the region lexicographically as specified by RECORD-REGEXP and KEY.
 397 RECORD-REGEXP specifies the textual units which should be sorted.
 398   For example, to sort lines RECORD-REGEXP would be \"^.*$\"
 399 KEY specifies the part of each record (ie each match for RECORD-REGEXP)
 400   is to be used for sorting.
 401   If it is \"\\\\digit\" then the digit'th \"\\\\(...\\\\)\" match field from
 402   RECORD-REGEXP is used.
 403   If it is \"\\\\&\" then the whole record is used.
 404   Otherwise, it is a regular-expression for which to search within the record.
 405 If a match for KEY is not found within a record then that record is ignored.
 406
 407 With a negative prefix arg sorts in reverse order.
 408
 409 The variable `sort-fold-case' determines whether alphabetic case affects
 410 the sort order.
 411
 412 For example: to sort lines in the region by the first word on each line
 413  starting with the letter \"f\",
 414  RECORD-REGEXP would be \"^.*$\" and KEY would be \"\\\\=\\<f\\\\w*\\\\>\""
 415   ;; using negative prefix arg to mean "reverse" is now inconsistent with
 416   ;; other sort-.*fields functions but then again this was before, since it
 417   ;; didn't use the magnitude of the arg to specify anything.
 418   (interactive "P\nsRegexp specifying records to sort:
 419 sRegexp specifying key within record: \nr")
 420   (cond ((or (equal key-regexp "") (equal key-regexp "\\&"))
 421          (setq key-regexp 0))
 422         ((string-match "\\`\\\\[1-9]\\'" key-regexp)
 423          (setq key-regexp (- (aref key-regexp 1) ?0))))
 424   (save-excursion
 425     (save-restriction
 426       (narrow-to-region beg end)
 427       (goto-char (point-min))
 428       (let (sort-regexp-record-end
 429             (sort-regexp-fields-regexp record-regexp))
 430         (re-search-forward sort-regexp-fields-regexp nil t)
 431         (setq sort-regexp-record-end (point))
 432         (goto-char (match-beginning 0))
 433         (sort-subr reverse
 434                    'sort-regexp-fields-next-record
 435                    (function (lambda ()
 436                                (goto-char sort-regexp-record-end)))
 437                    (function (lambda ()
 438                                (let ((n 0))
 439                                  (cond ((numberp key-regexp)
 440                                         (setq n key-regexp))
 441                                        ((re-search-forward
 442                                           key-regexp sort-regexp-record-end t)
 443                                         (setq n 0))
 444                                        (t (throw 'key nil)))
 445                                  (condition-case ()
 446                                      (cons (match-beginning n)
 447                                            (match-end n))
 448                                    ;; if there was no such register
 449                                    (error (throw 'key nil)))))))))))
 450
 451 \f
 452 (defvar sort-columns-subprocess t)
 453
 454 ;;;###autoload
 455 (defun sort-columns (reverse &optional beg end)
 456   "Sort lines in region alphabetically by a certain range of columns.
 457 For the purpose of this command, the region BEG...END includes
 458 the entire line that point is in and the entire line the mark is in.
 459 The column positions of point and mark bound the range of columns to sort on.
 460 A prefix argument means sort into REVERSE order.
 461 The variable `sort-fold-case' determines whether alphabetic case affects
 462 the sort order.
 463
 464 Note that `sort-columns' rejects text that contains tabs,
 465 because tabs could be split across the specified columns
 466 and it doesn't know how to handle that.  Also, when possible,
 467 it uses the `sort' utility program, which doesn't understand tabs.
 468 Use \\[untabify] to convert tabs to spaces before sorting."
 469   (interactive "P\nr")
 470   (save-excursion
 471     (let (beg1 end1 col-beg1 col-end1 col-start col-end)
 472       (goto-char (min beg end))
 473       (setq col-beg1 (current-column))
 474       (beginning-of-line)
 475       (setq beg1 (point))
 476       (goto-char (max beg end))
 477       (setq col-end1 (current-column))
 478       (forward-line)
 479       (setq end1 (point))
 480       (setq col-start (min col-beg1 col-end1))
 481       (setq col-end (max col-beg1 col-end1))
 482       (if (search-backward "\t" beg1 t)
 483           (error "sort-columns does not work with tabs -- use M-x untabify"))
 484       (if (not (or (memq system-type '(vax-vms windows-nt))
 485                    (let ((pos beg1) plist fontified)
 486                      (catch 'found
 487                        (while (< pos end1)
 488                          (setq plist (text-properties-at pos))
 489                          (setq fontified (plist-get plist 'fontified))
 490                          (while (consp plist)
 491                            (unless (or (eq (car plist) 'fontified)
 492                                        (and (eq (car plist) 'face)
 493                                             fontified))
 494                              (throw 'found t))
 495                            (setq plist (cddr plist)))
 496                          (setq pos (next-property-change pos nil end1)))))))
 497           ;; Use the sort utility if we can; it is 4 times as fast.
 498           ;; Do not use it if there are any non-font-lock properties
 499           ;; in the region, since the sort utility would lose the
 500           ;; properties.
 501           (let ((sort-args (list (if reverse "-rt\n" "-t\n")
 502                                  (concat "+0." (int-to-string col-start))
 503                                  (concat "-0." (int-to-string col-end)))))
 504             (when sort-fold-case
 505               (push "-f" sort-args))
 506             (apply #'call-process-region beg1 end1 "sort" t t nil sort-args))
 507         ;; On VMS and ms-windows, use Emacs's own facilities.
 508         (save-excursion
 509           (save-restriction
 510             (narrow-to-region beg1 end1)
 511             (goto-char beg1)
 512             (sort-subr reverse 'forward-line 'end-of-line
 513                        #'(lambda () (move-to-column col-start) nil)
 514                        #'(lambda () (move-to-column col-end) nil))))))))
 515
 516 ;;;###autoload
 517 (defun reverse-region (beg end)
 518   "Reverse the order of lines in a region.
 519 From a program takes two point or marker arguments, BEG and END."
 520   (interactive "r")
 521   (if (> beg end)
 522       (let (mid) (setq mid end end beg beg mid)))
 523   (save-excursion
 524     ;; put beg at the start of a line and end and the end of one --
 525     ;; the largest possible region which fits this criteria
 526     (goto-char beg)
 527     (or (bolp) (forward-line 1))
 528     (setq beg (point))
 529     (goto-char end)
 530     ;; the test for bolp is for those times when end is on an empty line;
 531     ;; it is probably not the case that the line should be included in the
 532     ;; reversal; it isn't difficult to add it afterward.
 533     (or (and (eolp) (not (bolp))) (progn (forward-line -1) (end-of-line)))
 534     (setq end (point-marker))
 535     ;; the real work.  this thing cranks through memory on large regions.
 536     (let (ll (do t))
 537       (while do
 538         (goto-char beg)
 539         (setq ll (cons (buffer-substring (point) (progn (end-of-line) (point)))
 540                        ll))
 541         (setq do (/= (point) end))
 542         (delete-region beg (if do (1+ (point)) (point))))
 543       (while (cdr ll)
 544         (insert (car ll) "\n")
 545         (setq ll (cdr ll)))
 546       (insert (car ll)))))
 547
 548 (provide 'sort)
 549
 550 ;;; arch-tag: fbac12be-2a7b-4c8a-9665-264d61f70bd9
 551 ;;; sort.el ends here