lisp/dabbrev.el

   1 ;;; dabbrev.el --- dynamic abbreviation package
   2
   3 ;; Copyright (C) 1985, 1986, 1992, 1994 Free Software Foundation, Inc.
   4
   5 ;; Author: Don Morrison
   6 ;; Maintainer: Lars Lindberg <Lars.Lindberg@sypro.cap.se>
   7 ;; Created: 16 Mars 1992
   8 ;; Lindberg's last update version: 5.7
   9 ;; Keywords: abbrev expand completion
  10
  11 ;; This file is part of GNU Emacs.
  12
  13 ;; GNU Emacs is free software; you can redistribute it and/or modify
  14 ;; it under the terms of the GNU General Public License as published by
  15 ;; the Free Software Foundation; either version 2, or (at your option)
  16 ;; any later version.
  17
  18 ;; GNU Emacs is distributed in the hope that it will be useful,
  19 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  20 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21 ;; GNU General Public License for more details.
  22
  23 ;; You should have received a copy of the GNU General Public License
  24 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  25 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  26 ;; Boston, MA 02111-1307, USA.
  27
  28 ;;; Commentary:
  29
  30 ;; The purpose with this package is to let you write just a few
  31 ;; characters of words you've written earlier to be able to expand
  32 ;; them.
  33 ;;
  34 ;; To expand a word, just put the point right after the word and press
  35 ;; M-/ (dabbrev-expand) or M-C-/ (dabbrev-completion).
  36 ;;
  37 ;; Check out the customizable variables below to learn about all the
  38 ;; features of this package.
  39
  40 ;;; Hints and tips for major modes writers:
  41
  42 ;; Recommended values           C/Lisp etc      text
  43 ;; dabbrev-case-fold-search     nil             t
  44 ;; dabbrev-case-replace         nil             t
  45 ;;
  46 ;; Set the variables you want special for your mode like this:
  47 ;; (set (make-local-variable 'dabbrev-case-replace) nil)
  48 ;; Then you don't interfere with other modes.
  49 ;;
  50 ;; If your mode handles buffers that refers to other buffers
  51 ;; (i.e. compilation-mode, gud-mode), then try to set
  52 ;; `dabbrev-select-buffers-function' or `dabbrev-friend-buffer-function'
  53 ;; to a function that point out those buffers.
  54
  55 ;; Same goes for major-modes that are connected to other modes.  There
  56 ;; are for instance a number of mail-modes.  One for reading, one for
  57 ;; creating a new mail etc.  Maybe those should be connected.
  58
  59 ;; Example for GNUS (when we write a reply, we want dabbrev to look in
  60 ;; the article for expansion):
  61 ;; (set (make-local-variable 'dabbrev-friend-buffer-function)
  62 ;;      (lambda (buffer)
  63 ;;         (save-excursion
  64 ;;           (set-buffer buffer)
  65 ;;           (memq major-mode '(news-reply-mode gnus-article-mode)))))
  66
  67
  68 ;; Known bugs and limitations.
  69 ;; - Possible to do several levels of `dabbrev-completion' in the
  70 ;;   minibuffer.
  71 ;; - dabbrev-completion doesn't handle resetting the globals variables
  72 ;;   right.  It resets them after finding the abbrev.
  73
  74 ;; Future enhancements
  75 ;;  - Check the tags-files? Like tags-complete?
  76 ;;  - Add the possibility of searching both forward and backward to
  77 ;;    the nearest expansion.
  78 ;;  - Check the kill-ring when everything else fails.  (Maybe something
  79 ;;  for hippie-expand?).  [Bng] <boris@cs.rochester.edu>
  80
  81 ;;; These people gave suggestions:
  82 ;;  [hymie]     Hyman Rosen <marks!hymie@jyacc.jyacc.com>
  83 ;;  [burgett]   Steve Burgett <burgett@bizet.eecs.berkeley.edu>
  84 ;;  [jules]     Julian Gosnell <jules@x.co.uk>
  85 ;;  [kifer]     Michael Kifer <kifer@sbcs.sunysb.edu>
  86 ;;  [ake]       Ake Stenhoff <extaksf@aom.ericsson.se>
  87 ;;  [alon]      Alon Albert <al%imercury@uunet.uu.net>
  88 ;;  [tromey]    Tom Tromey <tromey@busco.lanl.gov>
  89 ;;  [Rolf]      Rolf Schreiber <rolf@mathematik.uni-stuttgart.de>
  90 ;;  [Petri]     Petri Raitio <per@tekla.fi>
  91 ;;  [ejb]       Jay Berkenbilt <ejb@ERA.COM>
  92 ;;  [hawley]    Bob Hawley <rth1@quartet.mt.att.com>
  93 ;;  ... and to all the people who have participated in the beta tests.
  94
  95 ;;; Code:
  96
  97 ;;----------------------------------------------------------------
  98 ;; Customization variables
  99 ;;----------------------------------------------------------------
 100
 101 (defgroup dabbrev nil
 102   "Dynamic Abbreviations"
 103   :tag "Dynamic Abbreviations"
 104   :group 'abbrev)
 105
 106 (defcustom dabbrev-backward-only nil
 107   "*If non-nil, `dabbrev-expand' only looks backwards."
 108   :type 'boolean
 109   :group 'dabbrev)
 110
 111 (defcustom dabbrev-limit nil
 112   "*Limits region searched by `dabbrev-expand' to this many chars away."
 113   :type '(choice (const :tag "off" nil)
 114                  integer)
 115   :group 'dabbrev)
 116
 117 (defcustom dabbrev-abbrev-skip-leading-regexp nil
 118   "*Regexp for skipping leading characters of an abbreviation.
 119
 120 Example: Set this to \"\\\\$\" for programming languages
 121 in which variable names may appear with or without a leading `$'.
 122 \(For example, in Makefiles.
 123   :type 'regexp
 124   :group 'dabbrev))
 125
 126 Set this to nil if no characters should be skipped."
 127   :type '(choice regexp
 128                  (const :tag "off" nil))
 129   :group 'dabbrev)
 130
 131 (defcustom dabbrev-case-fold-search 'case-fold-search
 132   "*Control whether dabbrev searches should ignore case.
 133 A value of nil means case is significant.
 134 A value of `case-fold-search' means case is significant
 135  if `case-fold-search' is nil.
 136 Any other non-nil version means case is not significant."
 137   :type '(choice (const :tag "off" nil)
 138                  (const :tag "on" t)
 139                  (const :tag "like search" 'case-fold-search))
 140   :group 'dabbrev)
 141
 142 (defcustom dabbrev-upcase-means-case-search nil
 143   "*The significance of an uppercase character in an abbreviation.
 144 nil means case fold search, non-nil means case sensitive search.
 145
 146 This variable has an effect only when the value of
 147 `dabbrev-case-fold-search' says to ignore case."
 148   :type 'boolean
 149   :group 'dabbrev)
 150
 151 (defcustom dabbrev-case-replace 'case-replace
 152   "*Controls whether dabbrev preserves case when expanding the abbreviation.
 153 A value of nil means preserve case.
 154 A value of `case-replace' means preserve case if `case-replace' is nil.
 155 Any other non-nil version means do not preserve case.
 156
 157 This variable has an effect only when the value of
 158 `dabbrev-case-fold-search' specifies to ignore case."
 159   :type '(choice (const :tag "off" nil)
 160                  (const :tag "on" t)
 161                  (const :tag "like M-x query-replace" 'case-replace))
 162   :group 'dabbrev)
 163
 164 (defcustom dabbrev-abbrev-char-regexp nil
 165   "*Regexp to recognize a character in an abbreviation or expansion.
 166 This regexp will be surrounded with \\\\( ... \\\\) when actually used.
 167
 168 Set this variable to \"\\\\sw\" if you want ordinary words or
 169 \"\\\\sw\\\\|\\\\s_\" if you want symbols (including characters whose
 170 syntax is \"symbol\" as well as those whose syntax is \"word\".
 171
 172 The value nil has a special meaning: the abbreviation is from point to
 173 previous word-start, but the search is for symbols.
 174
 175 For instance, if you are programming in Lisp, `yes-or-no-p' is a symbol,
 176 while `yes', `or', `no' and `p' are considered words.  If this
 177 variable is nil, then expanding `yes-or-no-' looks for a symbol
 178 starting with or containing `no-'.  If you set this variable to
 179 \"\\\\sw\\\\|\\\\s_\", that expansion looks for a symbol starting with
 180 `yes-or-no-'.  Finally, if you set this variable to \"\\\\sw\", then
 181 expanding `yes-or-no-' signals an error because `-' is not part of a word;
 182 but expanding `yes-or-no' looks for a word starting with `no'.
 183
 184 The recommended value is \"\\\\sw\\\\|\\\\s_\"."
 185   :type '(choice (const nil)
 186                  regexp)
 187   :group 'dabbrev)
 188
 189 (defcustom dabbrev-check-all-buffers t
 190   "*Non-nil means dabbrev package should search *all* buffers.
 191
 192 Dabbrev always searches the current buffer first.  Then, if
 193 `dabbrev-check-other-buffers' says so, it searches the buffers
 194 designated by `dabbrev-select-buffers-function'.
 195
 196 Then, if `dabbrev-check-all-buffers' is non-nil, dabbrev searches
 197 all the other buffers."
 198   :type 'boolean
 199   :group 'dabbrev)
 200
 201 (defcustom dabbrev-check-other-buffers t
 202   "*Should \\[dabbrev-expand] look in other buffers?\
 203
 204 nil: Don't look in other buffers.
 205 t: Also look for expansions in the buffers pointed out by
 206    `dabbrev-select-buffers-function'.
 207 Anything else: When we can't find any more expansions in
 208 the current buffer, then ask the user whether to look in other
 209 buffers too.
 210
 211 The default value is t."
 212   :type '(choice (const :tag "off" nil)
 213                  (const :tag "on" t)
 214                  (const :tag "ask" other))
 215   :group 'dabbrev)
 216
 217 ;; I guess setting this to a function that selects all C- or C++-
 218 ;; mode buffers would be a good choice for a debugging buffer,
 219 ;; when debugging C- or C++-code.
 220 (defvar dabbrev-select-buffers-function 'dabbrev--select-buffers
 221   "A function that selects buffers that should be searched by dabbrev.
 222 The function should take no arguments and return a list of buffers to
 223 search for expansions.  Have a look at `dabbrev--select-buffers' for
 224 an example.
 225
 226 A mode setting this variable should make it buffer local.")
 227
 228 (defcustom dabbrev-friend-buffer-function 'dabbrev--same-major-mode-p
 229   "*A function to decide whether dabbrev should search OTHER-BUFFER.
 230 The function should take one argument, OTHER-BUFFER, and return
 231 non-nil if that buffer should be searched.  Have a look at
 232 `dabbrev--same-major-mode-p' for an example.
 233
 234 The value of `dabbrev-friend-buffer-function' has an effect only if
 235 the value of `dabbrev-select-buffers-function' uses it.  The function
 236 `dabbrev--select-buffers' is one function you can use here.
 237
 238 A mode setting this variable should make it buffer local."
 239   :type 'function
 240   :group 'dabbrev)
 241
 242 (defcustom dabbrev-search-these-buffers-only nil
 243   "If non-nil, a list of buffers which dabbrev should search.
 244 If this variable is non-nil, dabbrev will only look in these buffers.
 245 It will not even look in the current buffer if it is not a member of
 246 this list.")
 247
 248 ;;----------------------------------------------------------------
 249 ;; Internal variables
 250 ;;----------------------------------------------------------------
 251
 252 ;; Last obarray of completions in `dabbrev-completion'
 253 (defvar dabbrev--last-obarray nil)
 254
 255 ;; Table of expansions seen so far
 256 (defvar dabbrev--last-table nil)
 257
 258 ;; Last string we tried to expand.
 259 (defvar dabbrev--last-abbreviation nil)
 260
 261 ;; Location last abbreviation began
 262 (defvar dabbrev--last-abbrev-location nil)
 263
 264 ;; Direction of last dabbrevs search
 265 (defvar dabbrev--last-direction 0)
 266
 267 ;; Last expansion of an abbreviation.
 268 (defvar dabbrev--last-expansion nil)
 269
 270 ;; Location the last expansion was found.
 271 (defvar dabbrev--last-expansion-location nil)
 272
 273 ;; The list of remaining buffers with the same mode as current buffer.
 274 (defvar dabbrev--friend-buffer-list nil)
 275
 276 ;; The buffer we looked in last.
 277 (defvar dabbrev--last-buffer nil)
 278
 279 ;; The buffer we found the expansion last time.
 280 (defvar dabbrev--last-buffer-found nil)
 281
 282 ;; The buffer we last did a completion in.
 283 (defvar dabbrev--last-completion-buffer nil)
 284
 285 ;; Non-nil means we should upcase
 286 ;; when copying successive words.
 287 (defvar dabbrev--last-case-pattern nil)
 288
 289 ;; Same as dabbrev-check-other-buffers, but is set for every expand.
 290 (defvar dabbrev--check-other-buffers dabbrev-check-other-buffers)
 291
 292 ;; The regexp for recognizing a character in an abbreviation.
 293 (defvar dabbrev--abbrev-char-regexp nil)
 294
 295 ;;----------------------------------------------------------------
 296 ;; Macros
 297 ;;----------------------------------------------------------------
 298
 299 ;;; Get the buffer that mini-buffer was activated from
 300 (defsubst dabbrev--minibuffer-origin ()
 301   (car (cdr (buffer-list))))
 302
 303 ;; Make a list of some of the elements of LIST.
 304 ;; Check each element of LIST, storing it temporarily in the
 305 ;; variable ELEMENT, and include it in the result
 306 ;; if CONDITION evaluates non-nil.
 307 (defmacro dabbrev-filter-elements (element list condition)
 308   (` (let (dabbrev-result dabbrev-tail (, element))
 309        (setq dabbrev-tail (, list))
 310        (while dabbrev-tail
 311          (setq (, element) (car dabbrev-tail))
 312          (if (, condition)
 313              (setq dabbrev-result (cons (, element) dabbrev-result)))
 314          (setq dabbrev-tail (cdr dabbrev-tail)))
 315        (nreverse dabbrev-result))))
 316
 317 ;;----------------------------------------------------------------
 318 ;; Exported functions
 319 ;;----------------------------------------------------------------
 320
 321 ;;;###autoload
 322 (define-key esc-map "/" 'dabbrev-expand)
 323 ;;;??? Do we want this?
 324 ;;;###autoload
 325 (define-key esc-map [?\C-/] 'dabbrev-completion)
 326
 327 ;;;###autoload
 328 (defun dabbrev-completion (&optional arg)
 329   "Completion on current word.
 330 Like \\[dabbrev-expand] but finds all expansions in the current buffer
 331 and presents suggestions for completion.
 332
 333 With a prefix argument, it searches all buffers accepted by the
 334 function pointed out by `dabbrev-friend-buffer-function' to find the
 335 completions.
 336
 337 If the prefix argument is 16 (which comes from C-u C-u),
 338 then it searches *all* buffers.
 339
 340 With no prefix argument, it reuses an old completion list
 341 if there is a suitable one already."
 342
 343   (interactive "*P")
 344   (dabbrev--reset-global-variables)
 345   (let* ((dabbrev-check-other-buffers (and arg t))
 346          (dabbrev-check-all-buffers
 347           (and arg (= (prefix-numeric-value arg) 16)))
 348          (abbrev (dabbrev--abbrev-at-point))
 349          (ignore-case-p (and (if (eq dabbrev-case-fold-search 'case-fold-search)
 350                                  case-fold-search
 351                                dabbrev-case-fold-search)
 352                              (or (not dabbrev-upcase-means-case-search)
 353                                  (string= abbrev (downcase abbrev)))))
 354          (my-obarray dabbrev--last-obarray)
 355          init)
 356     (save-excursion
 357       (if (and (null arg)
 358                my-obarray
 359                (or (eq dabbrev--last-completion-buffer (current-buffer))
 360                    (and (window-minibuffer-p (selected-window))
 361                         (eq dabbrev--last-completion-buffer
 362                             (dabbrev--minibuffer-origin))))
 363                dabbrev--last-abbreviation
 364                (>= (length abbrev) (length dabbrev--last-abbreviation))
 365                (string= dabbrev--last-abbreviation
 366                         (substring abbrev 0
 367                                    (length dabbrev--last-abbreviation)))
 368                (setq init (try-completion abbrev my-obarray)))
 369           ;; We can reuse the existing completion list.
 370           nil
 371         ;;--------------------------------
 372         ;; New abbreviation to expand.
 373         ;;--------------------------------
 374         (setq dabbrev--last-abbreviation abbrev)
 375         ;; Find all expansion
 376         (let ((completion-list
 377                (dabbrev--find-all-expansions abbrev ignore-case-p))
 378               (completion-ignore-case ignore-case-p))
 379           ;; Make an obarray with all expansions
 380           (setq my-obarray (make-vector (length completion-list) 0))
 381           (or (> (length my-obarray) 0)
 382               (error "No dynamic expansion for \"%s\" found%s"
 383                      abbrev
 384                      (if dabbrev--check-other-buffers "" " in this-buffer")))
 385           (cond
 386            ((or (not ignore-case-p)
 387                 (not dabbrev-case-replace))
 388             (mapcar (function (lambda (string)
 389                                 (intern string my-obarray)))
 390                     completion-list))
 391            ((string= abbrev (upcase abbrev))
 392             (mapcar (function (lambda (string)
 393                                 (intern (upcase string) my-obarray)))
 394                     completion-list))
 395            ((string= (substring abbrev 0 1)
 396                      (upcase (substring abbrev 0 1)))
 397             (mapcar (function (lambda (string)
 398                                 (intern (capitalize string) my-obarray)))
 399                     completion-list))
 400            (t
 401             (mapcar (function (lambda (string)
 402                                 (intern (downcase string) my-obarray)))
 403                     completion-list)))
 404           (setq dabbrev--last-obarray my-obarray)
 405           (setq dabbrev--last-completion-buffer (current-buffer))
 406           ;; Find the longest common string.
 407           (setq init (try-completion abbrev my-obarray)))))
 408     ;;--------------------------------
 409     ;; Let the user choose between the expansions
 410     ;;--------------------------------
 411     (or (stringp init)
 412         (setq init abbrev))
 413     (cond
 414      ;; * Replace string fragment with matched common substring completion.
 415      ((and (not (string-equal init ""))
 416            (not (string-equal (downcase init) (downcase abbrev))))
 417       (if (> (length (all-completions init my-obarray)) 1)
 418           (message "Repeat `%s' to see all completions"
 419                    (key-description (this-command-keys)))
 420         (message "The only possible completion"))
 421       (dabbrev--substitute-expansion nil abbrev init))
 422      (t
 423       ;; * String is a common substring completion already.  Make list.
 424       (message "Making completion list...")
 425       (with-output-to-temp-buffer " *Completions*"
 426         (display-completion-list (all-completions init my-obarray)))
 427       (message "Making completion list...done")))
 428     (and (window-minibuffer-p (selected-window))
 429          (message nil))))
 430
 431 ;;;###autoload
 432 (defun dabbrev-expand (arg)
 433   "Expand previous word \"dynamically\".
 434
 435 Expands to the most recent, preceding word for which this is a prefix.
 436 If no suitable preceding word is found, words following point are
 437 considered.  If still no suitable word is found, then look in the
 438 buffers accepted by the function pointed out by variable
 439 `dabbrev-friend-buffer-function'.
 440
 441 A positive prefix argument, N, says to take the Nth backward *distinct*
 442 possibility.  A negative argument says search forward.
 443
 444 If the cursor has not moved from the end of the previous expansion and
 445 no argument is given, replace the previously-made expansion
 446 with the next possible expansion not yet tried.
 447
 448 The variable `dabbrev-backward-only' may be used to limit the
 449 direction of search to backward if set non-nil.
 450
 451 See also `dabbrev-abbrev-char-regexp' and \\[dabbrev-completion]."
 452   (interactive "*P")
 453   (let (abbrev record-case-pattern
 454                expansion old direction (orig-point (point)))
 455     ;; abbrev -- the abbrev to expand
 456     ;; expansion -- the expansion found (eventually) or nil until then
 457     ;; old -- the text currently in the buffer
 458     ;;    (the abbrev, or the previously-made expansion)
 459     (save-excursion
 460       (if (and (null arg)
 461                (markerp dabbrev--last-abbrev-location)
 462                (marker-position dabbrev--last-abbrev-location)
 463                (or (eq last-command this-command)
 464                    (and (window-minibuffer-p (selected-window))
 465                         (= dabbrev--last-abbrev-location
 466                            (point)))))
 467           ;; Find a different expansion for the same abbrev as last time.
 468           (progn
 469             (setq abbrev dabbrev--last-abbreviation)
 470             (setq old dabbrev--last-expansion)
 471             (setq direction dabbrev--last-direction))
 472         ;; If the user inserts a space after expanding
 473         ;; and then asks to expand again, always fetch the next word.
 474         (if (and (eq (preceding-char) ?\ )
 475                  (markerp dabbrev--last-abbrev-location)
 476                  (marker-position dabbrev--last-abbrev-location)
 477                  (= (point) (1+ dabbrev--last-abbrev-location)))
 478             (progn
 479               ;; The "abbrev" to expand is just the space.
 480               (setq abbrev " ")
 481               (save-excursion
 482                 (if dabbrev--last-buffer
 483                     (set-buffer dabbrev--last-buffer))
 484                 ;; Find the end of the last "expansion" word.
 485                 (if (or (eq dabbrev--last-direction 1)
 486                         (and (eq dabbrev--last-direction 0)
 487                              (< dabbrev--last-expansion-location (point))))
 488                     (setq dabbrev--last-expansion-location
 489                           (+ dabbrev--last-expansion-location
 490                              (length dabbrev--last-expansion))))
 491                 (goto-char dabbrev--last-expansion-location)
 492                 ;; Take the following word, with intermediate separators,
 493                 ;; as our expansion this time.
 494                 (re-search-forward
 495                  (concat "\\(\\(" dabbrev--abbrev-char-regexp "\\)+\\)"))
 496                 (setq expansion (buffer-substring-no-properties
 497                                  dabbrev--last-expansion-location (point)))
 498                 (if dabbrev--last-case-pattern
 499                     (setq expansion (upcase expansion)))
 500
 501                 ;; Record the end of this expansion, in case we repeat this.
 502                 (setq dabbrev--last-expansion-location (point)))
 503               ;; Indicate that dabbrev--last-expansion-location is
 504               ;; at the end of the expansion.
 505               (setq dabbrev--last-direction -1))
 506
 507           ;; We have a different abbrev to expand.
 508           (dabbrev--reset-global-variables)
 509           (setq direction (if (null arg)
 510                               (if dabbrev-backward-only 1 0)
 511                             (prefix-numeric-value arg)))
 512           (setq abbrev (dabbrev--abbrev-at-point))
 513           (setq record-case-pattern t)
 514           (setq old nil)))
 515
 516       ;;--------------------------------
 517       ;; Find the expansion
 518       ;;--------------------------------
 519       (or expansion
 520           (setq expansion
 521                 (dabbrev--find-expansion abbrev direction
 522                                          (and (if (eq dabbrev-case-fold-search 'case-fold-search)
 523                                                   case-fold-search
 524                                                 dabbrev-case-fold-search)
 525                                               (or (not dabbrev-upcase-means-case-search)
 526                                                   (string= abbrev (downcase abbrev))))))))
 527     (cond
 528      ((not expansion)
 529       (dabbrev--reset-global-variables)
 530       (if old
 531           (save-excursion
 532             (setq buffer-undo-list (cons orig-point buffer-undo-list))
 533             ;; Put back the original abbrev with its original case pattern.
 534             (search-backward old)
 535             (insert abbrev)
 536             (delete-region (point) (+ (point) (length old)))))
 537       (error "No%s dynamic expansion for `%s' found"
 538              (if old " further" "") abbrev))
 539      (t
 540       (if (not (eq dabbrev--last-buffer dabbrev--last-buffer-found))
 541           (progn
 542             (message "Expansion found in '%s'"
 543                      (buffer-name dabbrev--last-buffer))
 544             (setq dabbrev--last-buffer-found dabbrev--last-buffer))
 545         (message nil))
 546       (if (and (or (eq (current-buffer) dabbrev--last-buffer)
 547                    (null dabbrev--last-buffer))
 548                (numberp dabbrev--last-expansion-location)
 549                (and (> dabbrev--last-expansion-location (point))))
 550           (setq dabbrev--last-expansion-location
 551                 (copy-marker dabbrev--last-expansion-location)))
 552       ;; Success: stick it in and return.
 553       (setq buffer-undo-list (cons orig-point buffer-undo-list))
 554       (dabbrev--substitute-expansion old abbrev expansion)
 555
 556       ;; If we are not copying successive words now,
 557       ;; set dabbrev--last-case-pattern.
 558       (and record-case-pattern
 559            (setq dabbrev--last-case-pattern
 560                  (and (if (eq dabbrev-case-fold-search 'case-fold-search)
 561                           case-fold-search
 562                         dabbrev-case-fold-search)
 563                       (not dabbrev-upcase-means-case-search)
 564                       (equal abbrev (upcase abbrev)))))
 565
 566       ;; Save state for re-expand.
 567       (setq dabbrev--last-expansion expansion)
 568       (setq dabbrev--last-abbreviation abbrev)
 569       (setq dabbrev--last-abbrev-location (point-marker))))))
 570
 571 ;;----------------------------------------------------------------
 572 ;; Local functions
 573 ;;----------------------------------------------------------------
 574
 575 ;;; Checks if OTHER-BUFFER has the same major mode as current buffer.
 576 (defun dabbrev--same-major-mode-p (other-buffer)
 577   (eq major-mode
 578       (save-excursion
 579         (set-buffer other-buffer)
 580         major-mode)))
 581
 582 ;;; Back over all abbrev type characters and then moves forward over
 583 ;;; all skip characters.
 584 (defun dabbrev--goto-start-of-abbrev ()
 585   ;; Move backwards over abbrev chars
 586   (save-match-data
 587     (if (not (bobp))
 588         (progn
 589           (forward-char -1)
 590           (while (and (looking-at dabbrev--abbrev-char-regexp)
 591                       (not (bobp)))
 592             (forward-char -1))
 593           (or (looking-at dabbrev--abbrev-char-regexp)
 594               (forward-char 1))))
 595     (and dabbrev-abbrev-skip-leading-regexp
 596          (while (looking-at dabbrev-abbrev-skip-leading-regexp)
 597            (forward-char 1)))))
 598
 599 ;;; Extract the symbol at point to serve as abbreviation.
 600 (defun dabbrev--abbrev-at-point ()
 601   ;; Check for error
 602   (if (bobp)
 603       (error "No possible abbreviation preceding point"))
 604   ;; Return abbrev at point
 605   (save-excursion
 606     ;; Record the end of the abbreviation.
 607     (setq dabbrev--last-abbrev-location (point))
 608     ;; If we aren't right after an abbreviation,
 609     ;; move point back to just after one.
 610     ;; This is so the user can get successive words
 611     ;; by typing the punctuation followed by M-/.
 612     (save-match-data
 613       (if (save-excursion
 614             (forward-char -1)
 615             (not (looking-at (concat "\\("
 616                                      (or dabbrev-abbrev-char-regexp
 617                                          "\\sw\\|\\s_")
 618                                      "\\)+"))))
 619           (if (re-search-backward (or dabbrev-abbrev-char-regexp
 620                                       "\\sw\\|\\s_")
 621                                   nil t)
 622               (forward-char 1)
 623             (error "No possible abbreviation preceding point"))))
 624     ;; Now find the beginning of that one.
 625     (dabbrev--goto-start-of-abbrev)
 626     (buffer-substring-no-properties
 627      dabbrev--last-abbrev-location (point))))
 628
 629 ;;; Initializes all global variables
 630 (defun dabbrev--reset-global-variables ()
 631   ;; dabbrev--last-obarray and dabbrev--last-completion-buffer
 632   ;; must not be reset here.
 633   (setq dabbrev--last-table nil
 634         dabbrev--last-abbreviation nil
 635         dabbrev--last-abbrev-location nil
 636         dabbrev--last-direction nil
 637         dabbrev--last-expansion nil
 638         dabbrev--last-expansion-location nil
 639         dabbrev--friend-buffer-list nil
 640         dabbrev--last-buffer nil
 641         dabbrev--last-buffer-found nil
 642         dabbrev--abbrev-char-regexp (or dabbrev-abbrev-char-regexp
 643                                         "\\sw\\|\\s_")
 644         dabbrev--check-other-buffers dabbrev-check-other-buffers))
 645
 646 ;;; Find all buffers that are considered "friends" according to the
 647 ;;; function pointed out by dabbrev-friend-buffer-function.
 648 (defun dabbrev--select-buffers ()
 649   (save-excursion
 650     (and (window-minibuffer-p (selected-window))
 651          (set-buffer (dabbrev--minibuffer-origin)))
 652     (let ((orig-buffer (current-buffer)))
 653       (dabbrev-filter-elements
 654        buffer (buffer-list)
 655        (and (not (eq orig-buffer buffer))
 656             (boundp 'dabbrev-friend-buffer-function)
 657             (funcall dabbrev-friend-buffer-function buffer))))))
 658
 659 ;;; Search for ABBREV, N times, normally looking forward,
 660 ;;; but looking in reverse instead if REVERSE is non-nil.
 661 (defun dabbrev--try-find (abbrev reverse n ignore-case)
 662   (save-excursion
 663     (save-restriction
 664       (widen)
 665       (let ((expansion nil))
 666         (and dabbrev--last-expansion-location
 667              (goto-char dabbrev--last-expansion-location))
 668         (let ((case-fold-search ignore-case)
 669               (count n))
 670           (while (and (> count 0)
 671                       (setq expansion (dabbrev--search abbrev
 672                                                        reverse
 673                                                        ignore-case)))
 674             (setq count (1- count))))
 675         (and expansion
 676              (setq dabbrev--last-expansion-location (point)))
 677         expansion))))
 678
 679 ;;; Find all expansions of ABBREV
 680 (defun dabbrev--find-all-expansions (abbrev ignore-case)
 681   (let ((all-expansions nil)
 682         expansion)
 683     (save-excursion
 684       (goto-char (point-min))
 685       (while (setq expansion (dabbrev--find-expansion abbrev -1 ignore-case))
 686         (setq all-expansions (cons expansion all-expansions))))
 687     all-expansions))
 688
 689 (defun dabbrev--scanning-message ()
 690   (message "Scanning `%s'" (buffer-name (current-buffer))))
 691
 692 ;;; Find one occasion of ABBREV.
 693 ;;; DIRECTION > 0 means look that many times backwards.
 694 ;;; DIRECTION < 0 means look that many times forward.
 695 ;;; DIRECTION = 0 means try both backward and forward.
 696 ;;; IGNORE-CASE non-nil means ignore case when searching.
 697 (defun dabbrev--find-expansion (abbrev direction ignore-case)
 698   (let (expansion)
 699     (save-excursion
 700       (cond
 701        (dabbrev--last-buffer
 702         (set-buffer dabbrev--last-buffer)
 703         (dabbrev--scanning-message))
 704        ((and (not dabbrev-search-these-buffers-only)
 705              (window-minibuffer-p (selected-window)))
 706         (set-buffer (dabbrev--minibuffer-origin))
 707         ;; In the minibuffer-origin buffer we will only search from
 708         ;; the top and down.
 709         (goto-char (point-min))
 710         (setq direction -1)
 711         (dabbrev--scanning-message)))
 712       (cond
 713        ;; ------------------------------------------
 714        ;; Look backwards
 715        ;; ------------------------------------------
 716        ((and (not dabbrev-search-these-buffers-only)
 717              (>= direction 0)
 718              (setq dabbrev--last-direction (min 1 direction))
 719              (setq expansion (dabbrev--try-find abbrev t
 720                                                 (max 1 direction)
 721                                                 ignore-case)))
 722         expansion)
 723        ;; ------------------------------------------
 724        ;; Look forward
 725        ;; ------------------------------------------
 726        ((and (or (not dabbrev-search-these-buffers-only)
 727                  dabbrev--last-buffer)
 728              (<= direction 0)
 729              (setq dabbrev--last-direction -1)
 730              (setq expansion (dabbrev--try-find abbrev nil
 731                                                 (max 1 (- direction))
 732                                                 ignore-case)))
 733         expansion)
 734        ;; ------------------------------------------
 735        ;; Look in other buffers.
 736        ;; Start at (point-min) and look forward.
 737        ;; ------------------------------------------
 738        (t
 739         (setq dabbrev--last-direction -1)
 740         ;; Make sure that we should check other buffers
 741         (or dabbrev--friend-buffer-list
 742             dabbrev--last-buffer
 743             (setq dabbrev--friend-buffer-list
 744                   (mapcar (function get-buffer)
 745                           dabbrev-search-these-buffers-only))
 746             (not dabbrev--check-other-buffers)
 747             (not (or (eq dabbrev--check-other-buffers t)
 748                      (progn
 749                        (setq dabbrev--check-other-buffers
 750                              (y-or-n-p "Scan other buffers also? ")))))
 751             (let* (friend-buffer-list non-friend-buffer-list)
 752               (setq dabbrev--friend-buffer-list
 753                     (funcall dabbrev-select-buffers-function))
 754               (if dabbrev-check-all-buffers
 755                   (setq non-friend-buffer-list
 756                         (nreverse
 757                          (dabbrev-filter-elements
 758                           buffer (buffer-list)
 759                           (not (memq buffer dabbrev--friend-buffer-list))))
 760                         dabbrev--friend-buffer-list
 761                         (append dabbrev--friend-buffer-list
 762                                 non-friend-buffer-list)))))
 763         ;; Move buffers that are visible on the screen
 764         ;; to the front of the list.
 765         (if dabbrev--friend-buffer-list
 766             (let ((w (next-window (selected-window))))
 767               (while (not (eq w (selected-window)))
 768                 (setq dabbrev--friend-buffer-list
 769                       (cons (window-buffer w)
 770                             (delq (window-buffer w) dabbrev--friend-buffer-list)))
 771                 (setq w (next-window w)))))
 772         ;; Walk through the buffers
 773         (while (and (not expansion) dabbrev--friend-buffer-list)
 774           (setq dabbrev--last-buffer
 775                 (car dabbrev--friend-buffer-list))
 776           (setq dabbrev--friend-buffer-list
 777                 (cdr dabbrev--friend-buffer-list))
 778           (set-buffer dabbrev--last-buffer)
 779           (dabbrev--scanning-message)
 780           (setq dabbrev--last-expansion-location (point-min))
 781           (setq expansion (dabbrev--try-find abbrev nil 1 ignore-case)))
 782         expansion)))))
 783
 784 (defun dabbrev--safe-replace-match (string &optional fixedcase literal)
 785   (if (eq major-mode 'picture-mode)
 786       (picture-replace-match string fixedcase literal)
 787     (replace-match string fixedcase literal)))
 788
 789 ;;;----------------------------------------------------------------
 790 ;;; Substitute the current string in buffer with the expansion
 791 ;;; OLD is nil or the last expansion substring.
 792 ;;; ABBREV is the abbreviation we are working with.
 793 ;;; EXPANSION is the expansion substring.
 794 (defun dabbrev--substitute-expansion (old abbrev expansion)
 795   ;;(undo-boundary)
 796   (let ((use-case-replace (and (if (eq dabbrev-case-fold-search 'case-fold-search)
 797                                    case-fold-search
 798                                  dabbrev-case-fold-search)
 799                                (or (not dabbrev-upcase-means-case-search)
 800                                    (string= abbrev (downcase abbrev)))
 801                                (if (eq dabbrev-case-replace 'case-replace)
 802                                    case-replace
 803                                  dabbrev-case-replace))))
 804     (and nil use-case-replace
 805          (setq old (concat abbrev (or old "")))
 806          (setq expansion (concat abbrev expansion)))
 807     ;; If the expansion has mixed case
 808     ;; and it is not simply a capitalized word,
 809     ;; or if the abbrev has mixed case,
 810     ;; and if the given abbrev's case pattern
 811     ;; matches the start of the expansion,
 812     ;; copy the expansion's case
 813     ;; instead of downcasing all the rest.
 814     (let ((expansion-rest (substring expansion 1)))
 815       (if (and (not (and (or (string= expansion-rest (downcase expansion-rest))
 816                              (string= expansion-rest (upcase expansion-rest)))
 817                          (or (string= abbrev (downcase abbrev))
 818                              (string= abbrev (upcase abbrev)))))
 819                (string= abbrev
 820                         (substring expansion 0 (length abbrev))))
 821           (setq use-case-replace nil)))
 822     (if (equal abbrev " ")
 823         (setq use-case-replace nil))
 824     (if use-case-replace
 825         (setq expansion (downcase expansion)))
 826     (if old
 827         (save-excursion
 828           (search-backward old))
 829       ;;(store-match-data (list (point-marker) (point-marker)))
 830       (search-backward abbrev))
 831     ;; Make case of replacement conform to case of abbreviation
 832     ;; provided (1) that kind of thing is enabled in this buffer
 833     ;; and (2) the replacement itself is all lower case.
 834     (dabbrev--safe-replace-match expansion
 835                                  (not use-case-replace)
 836                                  t)))
 837
 838
 839 ;;;----------------------------------------------------------------
 840 ;;; Search function used by dabbrevs library.
 841
 842 ;;; ABBREV is string to find as prefix of word.  Second arg, REVERSE,
 843 ;;; is t for reverse search, nil for forward.  Variable dabbrev-limit
 844 ;;; controls the maximum search region size.  Third argument IGNORE-CASE
 845 ;;; non-nil means treat case as insignificant while looking for a match
 846 ;;; and when comparing with previous matches.  Also if that's non-nil
 847 ;;; and the match is found at the beginning of a sentence and is in
 848 ;;; lower case except for the initial then it is converted to all lower
 849 ;;; case for return.
 850
 851 ;;; Table of expansions already seen is examined in buffer
 852 ;;; `dabbrev--last-table' so that only distinct possibilities are found
 853 ;;; by dabbrev-re-expand.
 854
 855 ;;; Value is the expansion, or nil if not found.
 856
 857 (defun dabbrev--search (abbrev reverse ignore-case)
 858   (save-match-data
 859     (let ((pattern1 (concat (regexp-quote abbrev)
 860                             "\\(" dabbrev--abbrev-char-regexp "\\)"))
 861           (pattern2 (concat (regexp-quote abbrev)
 862                            "\\(\\(" dabbrev--abbrev-char-regexp "\\)+\\)"))
 863           (found-string nil))
 864       ;; Limited search.
 865       (save-restriction
 866         (and dabbrev-limit
 867              (narrow-to-region dabbrev--last-expansion-location
 868                                (+ (point)
 869                                   (if reverse (- dabbrev-limit) dabbrev-limit))))
 870         ;;--------------------------------
 871         ;; Look for a distinct expansion, using dabbrev--last-table.
 872         ;;--------------------------------
 873         (while (and (not found-string)
 874                     (if reverse
 875                         (re-search-backward pattern1 nil t)
 876                       (re-search-forward pattern1 nil t)))
 877           (goto-char (match-beginning 0))
 878           ;; In case we matched in the middle of a word,
 879           ;; back up to start of word and verify we still match.
 880           (dabbrev--goto-start-of-abbrev)
 881
 882           (if (not (looking-at pattern1))
 883               nil
 884             ;; We have a truly valid match.  Find the end.
 885             (re-search-forward pattern2)
 886             (setq found-string (buffer-substring-no-properties
 887                                 (match-beginning 1) (match-end 1)))
 888             (and ignore-case (setq found-string (downcase found-string)))
 889             ;; Ignore this match if it's already in the table.
 890             (if (dabbrev-filter-elements
 891                  table-string dabbrev--last-table
 892                  (string= found-string table-string))
 893                 (setq found-string nil)))
 894           ;; Prepare to continue searching.
 895           (if reverse
 896               (goto-char (match-beginning 0))
 897             (goto-char (match-end 0))))
 898         ;; If we found something, use it.
 899         (if found-string
 900             ;; Put it into `dabbrev--last-table'
 901             ;; and return it (either downcased, or as is).
 902             (let ((result (buffer-substring-no-properties
 903                            (match-beginning 0) (match-end 0))))
 904               (setq dabbrev--last-table
 905                     (cons found-string dabbrev--last-table))
 906               (if (and ignore-case (eval dabbrev-case-replace))
 907                   result
 908                 result)))))))
 909
 910 (provide 'dabbrev)
 911
 912 ;;; dabbrev.el ends here