lisp/emulation/viper-util.el

   1 ;;; viper-util.el --- Utilities used by viper.el
   2
   3 ;; Copyright (C) 1994, 95, 96, 97, 99, 2000, 01, 02, 2005 Free Software Foundation, Inc.
   4
   5 ;; Author: Michael Kifer <kifer@cs.stonybrook.edu>
   6
   7 ;; This file is part of GNU Emacs.
   8
   9 ;; GNU Emacs is free software; you can redistribute it and/or modify
  10 ;; it under the terms of the GNU General Public License as published by
  11 ;; the Free Software Foundation; either version 2, or (at your option)
  12 ;; any later version.
  13
  14 ;; GNU Emacs is distributed in the hope that it will be useful,
  15 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 ;; GNU General Public License for more details.
  18
  19 ;; You should have received a copy of the GNU General Public License
  20 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  21 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  22 ;; Boston, MA 02111-1307, USA.
  23
  24 ;;; Commentary:
  25
  26 ;;; Code:
  27
  28 ;; Compiler pacifier
  29 (defvar viper-overriding-map)
  30 (defvar pm-color-alist)
  31 (defvar zmacs-region-stays)
  32 (defvar viper-minibuffer-current-face)
  33 (defvar viper-minibuffer-insert-face)
  34 (defvar viper-minibuffer-vi-face)
  35 (defvar viper-minibuffer-emacs-face)
  36 (defvar viper-replace-overlay-face)
  37 (defvar viper-fast-keyseq-timeout)
  38 (defvar ex-unix-type-shell)
  39 (defvar ex-unix-type-shell-options)
  40 (defvar viper-ex-tmp-buf-name)
  41 (defvar viper-syntax-preference)
  42 (defvar viper-saved-mark)
  43
  44 (require 'cl)
  45 (require 'ring)
  46
  47 (if noninteractive
  48     (eval-when-compile
  49       (let ((load-path (cons (expand-file-name ".") load-path)))
  50         (or (featurep 'viper-init)
  51             (load "viper-init.el" nil nil 'nosuffix))
  52         )))
  53 ;; end pacifier
  54
  55 (require 'viper-init)
  56
  57
  58 ;; A fix for NeXT Step
  59 ;; Should go away, when NS people fix the design flaw, which leaves the
  60 ;; two x-* functions undefined.
  61 (if (and (not (fboundp 'x-display-color-p)) (fboundp 'ns-display-color-p))
  62     (fset 'x-display-color-p (symbol-function 'ns-display-color-p)))
  63 (if (and (not (fboundp 'x-color-defined-p)) (fboundp 'ns-color-defined-p))
  64       (fset 'x-color-defined-p (symbol-function 'ns-color-defined-p)))
  65
  66 \f
  67 ;;; XEmacs support
  68
  69
  70 (viper-cond-compile-for-xemacs-or-emacs
  71  (progn ; xemacs
  72    (fset 'viper-overlay-p (symbol-function 'extentp))
  73    (fset 'viper-make-overlay (symbol-function 'make-extent))
  74    (fset 'viper-overlay-live-p (symbol-function 'extent-live-p))
  75    (fset 'viper-move-overlay (symbol-function 'set-extent-endpoints))
  76    (fset 'viper-overlay-start (symbol-function 'extent-start-position))
  77    (fset 'viper-overlay-end (symbol-function 'extent-end-position))
  78    (fset 'viper-overlay-get (symbol-function 'extent-property))
  79    (fset 'viper-overlay-put (symbol-function 'set-extent-property))
  80    (fset 'viper-read-event (symbol-function 'next-command-event))
  81    (fset 'viper-characterp (symbol-function 'characterp))
  82    (fset 'viper-int-to-char (symbol-function 'int-to-char))
  83    (if (viper-window-display-p)
  84        (fset 'viper-iconify (symbol-function 'iconify-frame)))
  85    (cond ((viper-has-face-support-p)
  86           (fset 'viper-get-face (symbol-function 'get-face))
  87           (fset 'viper-color-defined-p (symbol-function 'valid-color-name-p))
  88           )))
  89  (progn ; emacs
  90    (fset 'viper-overlay-p (symbol-function 'overlayp))
  91    (fset 'viper-make-overlay (symbol-function 'make-overlay))
  92    (fset 'viper-overlay-live-p (symbol-function 'overlayp))
  93    (fset 'viper-move-overlay (symbol-function 'move-overlay))
  94    (fset 'viper-overlay-start (symbol-function 'overlay-start))
  95    (fset 'viper-overlay-end (symbol-function 'overlay-end))
  96    (fset 'viper-overlay-get (symbol-function 'overlay-get))
  97    (fset 'viper-overlay-put (symbol-function 'overlay-put))
  98    (fset 'viper-read-event (symbol-function 'read-event))
  99    (fset 'viper-characterp (symbol-function 'integerp))
 100    (fset 'viper-int-to-char (symbol-function 'identity))
 101    (if (viper-window-display-p)
 102        (fset 'viper-iconify (symbol-function 'iconify-or-deiconify-frame)))
 103    (cond ((viper-has-face-support-p)
 104           (fset 'viper-get-face (symbol-function 'internal-get-face))
 105           (fset 'viper-color-defined-p (symbol-function 'x-color-defined-p))
 106           )))
 107  )
 108
 109
 110
 111 ;; CHAR is supposed to be a char or an integer (positive or negative)
 112 ;; LIST is a list of chars, nil, and negative numbers
 113 ;; Check if CHAR is a member by trying to convert in characters, if necessary.
 114 ;; Introduced for compatibility with XEmacs, where integers are not the same as
 115 ;; chars.
 116 (defun viper-memq-char (char list)
 117   (cond ((and (integerp char) (>= char 0))
 118          (memq (viper-int-to-char char) list))
 119         ((memq char list))))
 120
 121 ;; Check if char-or-int and char are the same as characters
 122 (defun viper-char-equal (char-or-int char)
 123   (cond ((and (integerp char-or-int) (>= char-or-int 0))
 124          (= (viper-int-to-char char-or-int) char))
 125         ((eq char-or-int char))))
 126
 127 ;; Like =, but accommodates null and also is t for eq-objects
 128 (defun viper= (char char1)
 129   (cond ((eq char char1) t)
 130         ((and (viper-characterp char) (viper-characterp char1))
 131          (= char char1))
 132         (t nil)))
 133
 134 (defsubst viper-color-display-p ()
 135   (viper-cond-compile-for-xemacs-or-emacs
 136    (eq (device-class (selected-device)) 'color) ; xemacs
 137    (x-display-color-p)  ; emacs
 138    ))
 139
 140 (defsubst viper-get-cursor-color ()
 141   (viper-cond-compile-for-xemacs-or-emacs
 142    ;; xemacs
 143    (color-instance-name (frame-property (selected-frame) 'cursor-color))
 144    (cdr (assoc 'cursor-color (frame-parameters))) ; emacs
 145    ))
 146
 147
 148 ;; OS/2
 149 (cond ((eq (viper-device-type) 'pm)
 150        (fset 'viper-color-defined-p
 151              (lambda (color) (assoc color pm-color-alist)))))
 152
 153
 154 ;; cursor colors
 155 (defun viper-change-cursor-color (new-color)
 156   (if (and (viper-window-display-p)  (viper-color-display-p)
 157            (stringp new-color) (viper-color-defined-p new-color)
 158            (not (string= new-color (viper-get-cursor-color))))
 159       (viper-cond-compile-for-xemacs-or-emacs
 160        (set-frame-property
 161         (selected-frame) 'cursor-color (make-color-instance new-color))
 162        (modify-frame-parameters
 163         (selected-frame) (list (cons 'cursor-color new-color)))
 164        )
 165     ))
 166
 167 ;; By default, saves current frame cursor color in the
 168 ;; viper-saved-cursor-color-in-replace-mode property of viper-replace-overlay
 169 (defun viper-save-cursor-color (before-which-mode)
 170   (if (and (viper-window-display-p) (viper-color-display-p))
 171       (let ((color (viper-get-cursor-color)))
 172         (if (and (stringp color) (viper-color-defined-p color)
 173                  (not (string= color viper-replace-overlay-cursor-color)))
 174             (modify-frame-parameters
 175              (selected-frame)
 176              (list
 177               (cons
 178                (if (eq before-which-mode 'before-replace-mode)
 179                    'viper-saved-cursor-color-in-replace-mode
 180                  'viper-saved-cursor-color-in-insert-mode)
 181                color)))
 182           ))))
 183
 184
 185 (defsubst viper-get-saved-cursor-color-in-replace-mode ()
 186   (or
 187    (funcall
 188     (if viper-emacs-p 'frame-parameter 'frame-property)
 189     (selected-frame)
 190     'viper-saved-cursor-color-in-replace-mode)
 191    viper-vi-state-cursor-color))
 192
 193 (defsubst viper-get-saved-cursor-color-in-insert-mode ()
 194   (or
 195    (funcall
 196     (if viper-emacs-p 'frame-parameter 'frame-property)
 197     (selected-frame)
 198     'viper-saved-cursor-color-in-insert-mode)
 199    viper-vi-state-cursor-color))
 200
 201 ;; restore cursor color from replace overlay
 202 (defun viper-restore-cursor-color(after-which-mode)
 203   (if (viper-overlay-p viper-replace-overlay)
 204       (viper-change-cursor-color
 205        (if (eq after-which-mode 'after-replace-mode)
 206            (viper-get-saved-cursor-color-in-replace-mode)
 207          (viper-get-saved-cursor-color-in-insert-mode))
 208        )))
 209
 210 \f
 211 ;; Check the current version against the major and minor version numbers
 212 ;; using op: cur-vers op major.minor If emacs-major-version or
 213 ;; emacs-minor-version are not defined, we assume that the current version
 214 ;; is hopelessly outdated.  We assume that emacs-major-version and
 215 ;; emacs-minor-version are defined.  Otherwise, for Emacs/XEmacs 19, if the
 216 ;; current minor version is < 10 (xemacs) or < 23 (emacs) the return value
 217 ;; will be nil (when op is =, >, or >=) and t (when op is <, <=), which may be
 218 ;; incorrect.  However, this gives correct result in our cases, since we are
 219 ;; testing for sufficiently high Emacs versions.
 220 (defun viper-check-version (op major minor &optional type-of-emacs)
 221   (if (and (boundp 'emacs-major-version) (boundp 'emacs-minor-version))
 222       (and (cond ((eq type-of-emacs 'xemacs) viper-xemacs-p)
 223                  ((eq type-of-emacs 'emacs) viper-emacs-p)
 224                  (t t))
 225            (cond ((eq op '=) (and (= emacs-minor-version minor)
 226                                   (= emacs-major-version major)))
 227                  ((memq op '(> >= < <=))
 228                   (and (or (funcall op emacs-major-version major)
 229                            (= emacs-major-version major))
 230                        (if (= emacs-major-version major)
 231                            (funcall op emacs-minor-version minor)
 232                          t)))
 233                  (t
 234                   (error "%S: Invalid op in viper-check-version" op))))
 235     (cond ((memq op '(= > >=)) nil)
 236           ((memq op '(< <=)) t))))
 237
 238
 239 (defun viper-get-visible-buffer-window (wind)
 240   (if viper-xemacs-p
 241       (get-buffer-window wind t)
 242     (get-buffer-window wind 'visible)))
 243
 244
 245 ;; Return line position.
 246 ;; If pos is 'start then returns position of line start.
 247 ;; If pos is 'end, returns line end.  If pos is 'mid, returns line center.
 248 ;; Pos = 'indent returns beginning of indentation.
 249 ;; Otherwise, returns point.  Current point is not moved in any case."
 250 (defun viper-line-pos (pos)
 251   (let ((cur-pos (point))
 252         (result))
 253     (cond
 254      ((equal pos 'start)
 255       (beginning-of-line))
 256      ((equal pos 'end)
 257       (end-of-line))
 258      ((equal pos 'mid)
 259       (goto-char (+ (viper-line-pos 'start) (viper-line-pos 'end) 2)))
 260      ((equal pos 'indent)
 261       (back-to-indentation))
 262      (t   nil))
 263     (setq result (point))
 264     (goto-char cur-pos)
 265     result))
 266
 267 ;; Emacs used to count each multibyte character as several positions in the buffer,
 268 ;; so we had to use Emacs' chars-in-region to count characters. Since 20.3,
 269 ;; Emacs counts multibyte characters as 1 position.  XEmacs has always been
 270 ;; counting each char as just one pos. So, now we can simply subtract beg from
 271 ;; end to determine the number of characters in a region.
 272 (defun viper-chars-in-region (beg end &optional preserve-sign)
 273   ;;(let ((count (abs (if (fboundp 'chars-in-region)
 274   ;;                    (chars-in-region beg end)
 275   ;;                  (- end beg)))))
 276   (let ((count (abs (- end beg))))
 277     (if (and (< end beg) preserve-sign)
 278         (- count)
 279       count)))
 280
 281 ;; Test if POS is between BEG and END
 282 (defsubst viper-pos-within-region (pos beg end)
 283   (and (>= pos (min beg end)) (>= (max beg end) pos)))
 284
 285
 286 ;; Like move-marker but creates a virgin marker if arg isn't already a marker.
 287 ;; The first argument must eval to a variable name.
 288 ;; Arguments: (var-name position &optional buffer).
 289 ;;
 290 ;; This is useful for moving markers that are supposed to be local.
 291 ;; For this, VAR-NAME should be made buffer-local with nil as a default.
 292 ;; Then, each time this var is used in `viper-move-marker-locally' in a new
 293 ;; buffer, a new marker will be created.
 294 (defun viper-move-marker-locally (var pos &optional buffer)
 295   (if (markerp (eval var))
 296       ()
 297     (set var (make-marker)))
 298   (move-marker (eval var) pos buffer))
 299
 300
 301 ;; Print CONDITIONS as a message.
 302 (defun viper-message-conditions (conditions)
 303   (let ((case (car conditions)) (msg (cdr conditions)))
 304     (if (null msg)
 305         (message "%s" case)
 306       (message "%s: %s" case (mapconcat 'prin1-to-string msg " ")))
 307     (beep 1)))
 308
 309
 310 \f
 311 ;;; List/alist utilities
 312
 313 ;; Convert LIST to an alist
 314 (defun viper-list-to-alist (lst)
 315   (let ((alist))
 316     (while lst
 317       (setq alist (cons (list (car lst)) alist))
 318       (setq lst (cdr lst)))
 319     alist))
 320
 321 ;; Convert ALIST to a list.
 322 (defun viper-alist-to-list (alst)
 323   (let ((lst))
 324     (while alst
 325       (setq lst (cons (car (car alst)) lst))
 326       (setq alst (cdr alst)))
 327     lst))
 328
 329 ;; Filter ALIST using REGEXP.  Return alist whose elements match the regexp.
 330 (defun viper-filter-alist (regexp alst)
 331   (interactive "s x")
 332   (let ((outalst) (inalst alst))
 333     (while (car inalst)
 334       (if (string-match regexp (car (car inalst)))
 335           (setq outalst (cons (car inalst) outalst)))
 336       (setq inalst (cdr inalst)))
 337     outalst))
 338
 339 ;; Filter LIST using REGEXP.  Return list whose elements match the regexp.
 340 (defun viper-filter-list (regexp lst)
 341   (interactive "s x")
 342   (let ((outlst) (inlst lst))
 343     (while (car inlst)
 344       (if (string-match regexp (car inlst))
 345           (setq outlst (cons (car inlst) outlst)))
 346       (setq inlst (cdr inlst)))
 347     outlst))
 348
 349
 350 ;; Append LIS2 to LIS1, both alists, by side-effect and returns LIS1
 351 ;; LIS2 is modified by filtering it: deleting its members of the form
 352 ;; \(car elt\) such that (car elt') is in LIS1.
 353 (defun viper-append-filter-alist (lis1 lis2)
 354   (let ((temp lis1)
 355         elt)
 356     ;;filter-append the second list
 357     (while temp
 358       ;; delete all occurrences
 359       (while (setq elt (assoc (car (car temp)) lis2))
 360         (setq lis2 (delq elt lis2)))
 361       (setq temp (cdr temp)))
 362
 363     (nconc lis1 lis2)))
 364
 365
 366 \f
 367 ;;; Support for :e, :r, :w file globbing
 368
 369 ;; Glob the file spec.
 370 ;; This function is designed to work under Unix.  It might also work under VMS.
 371 (defun viper-glob-unix-files (filespec)
 372   (let ((gshell
 373          (cond (ex-unix-type-shell shell-file-name)
 374                ((memq system-type '(vax-vms axp-vms)) "*dcl*") ; VAX VMS
 375                (t "sh"))) ; probably Unix anyway
 376         (gshell-options
 377          ;; using cond in anticipation of further additions
 378          (cond (ex-unix-type-shell-options)
 379                ))
 380         (command (cond (viper-ms-style-os-p (format "\"ls -1 -d %s\"" filespec))
 381                        (t (format "ls -1 -d %s" filespec))))
 382         status)
 383     (save-excursion
 384       (set-buffer (get-buffer-create viper-ex-tmp-buf-name))
 385       (erase-buffer)
 386       (setq status
 387             (if gshell-options
 388                 (call-process gshell nil t nil
 389                               gshell-options
 390                               "-c"
 391                               command)
 392               (call-process gshell nil t nil
 393                             "-c"
 394                             command)))
 395       (goto-char (point-min))
 396       ;; Issue an error, if no match.
 397       (unless (eq 0 status)
 398         (save-excursion
 399           (skip-chars-forward " \t\n\j")
 400           (if (looking-at "ls:")
 401               (viper-forward-Word 1))
 402           (error "%s: %s"
 403                  (if (stringp  gshell)
 404                      gshell
 405                    "shell")
 406                  (buffer-substring (point) (viper-line-pos 'end)))
 407           ))
 408       (goto-char (point-min))
 409       (viper-get-filenames-from-buffer 'one-per-line))
 410     ))
 411
 412
 413 ;; Interpret the stuff in the buffer as a list of file names
 414 ;; return a list of file names listed in the buffer beginning at point
 415 ;; If optional arg is supplied, assume each filename is listed on a separate
 416 ;; line
 417 (defun viper-get-filenames-from-buffer (&optional one-per-line)
 418   (let ((skip-chars (if one-per-line "\t\n" " \t\n"))
 419          result fname delim)
 420     (skip-chars-forward skip-chars)
 421     (while (not (eobp))
 422       (if (cond ((looking-at "\"")
 423                  (setq delim ?\")
 424                  (re-search-forward "[^\"]+" nil t)) ; noerror
 425                 ((looking-at "'")
 426                  (setq delim ?')
 427                  (re-search-forward "[^']+" nil t)) ; noerror
 428                 (t
 429                  (re-search-forward
 430                   (concat "[^" skip-chars "]+") nil t))) ;noerror
 431           (setq fname
 432                 (buffer-substring (match-beginning 0) (match-end 0))))
 433       (if delim
 434           (forward-char 1))
 435       (skip-chars-forward " \t\n")
 436       (setq result (cons fname result)))
 437     result))
 438
 439 ;; convert MS-DOS wildcards to regexp
 440 (defun viper-wildcard-to-regexp (wcard)
 441   (save-excursion
 442     (set-buffer (get-buffer-create viper-ex-tmp-buf-name))
 443     (erase-buffer)
 444     (insert wcard)
 445     (goto-char (point-min))
 446     (while (not (eobp))
 447       (skip-chars-forward "^*?.\\\\")
 448       (cond ((eq (char-after (point)) ?*) (insert ".")(forward-char 1))
 449             ((eq (char-after (point)) ?.) (insert "\\")(forward-char 1))
 450             ((eq (char-after (point)) ?\\) (insert "\\")(forward-char 1))
 451             ((eq (char-after (point)) ??) (delete-char 1)(insert ".")))
 452       )
 453     (buffer-string)
 454     ))
 455
 456
 457 ;; glob windows files
 458 ;; LIST is expected to be in reverse order
 459 (defun viper-glob-mswindows-files (filespec)
 460   (let ((case-fold-search t)
 461         tmp tmp2)
 462     (save-excursion
 463       (set-buffer (get-buffer-create viper-ex-tmp-buf-name))
 464       (erase-buffer)
 465       (insert filespec)
 466       (goto-char (point-min))
 467       (setq tmp (viper-get-filenames-from-buffer))
 468       (while tmp
 469         (setq tmp2 (cons (directory-files
 470                           ;; the directory part
 471                           (or (file-name-directory (car tmp))
 472                               "")
 473                           t  ; return full names
 474                           ;; the regexp part: globs the file names
 475                           (concat "^"
 476                                   (viper-wildcard-to-regexp
 477                                    (file-name-nondirectory (car tmp)))
 478                                   "$"))
 479                          tmp2))
 480         (setq tmp (cdr tmp)))
 481       (reverse (apply 'append tmp2)))))
 482
 483 \f
 484 ;;; Insertion ring
 485
 486 ;; Rotate RING's index.  DIRection can be positive or negative.
 487 (defun viper-ring-rotate1 (ring dir)
 488   (if (and (ring-p ring) (> (ring-length ring) 0))
 489       (progn
 490         (setcar ring (cond ((> dir 0)
 491                             (ring-plus1 (car ring) (ring-length ring)))
 492                            ((< dir 0)
 493                             (ring-minus1 (car ring) (ring-length ring)))
 494                            ;; don't rotate if dir = 0
 495                            (t (car ring))))
 496         (viper-current-ring-item ring)
 497         )))
 498
 499 (defun viper-special-ring-rotate1 (ring dir)
 500   (if (memq viper-intermediate-command
 501             '(repeating-display-destructive-command
 502               repeating-insertion-from-ring))
 503       (viper-ring-rotate1 ring dir)
 504     ;; don't rotate otherwise
 505     (viper-ring-rotate1 ring 0)))
 506
 507 ;; current ring item; if N is given, then so many items back from the
 508 ;; current
 509 (defun viper-current-ring-item (ring &optional n)
 510   (setq n (or n 0))
 511   (if (and (ring-p ring) (> (ring-length ring) 0))
 512       (aref (cdr (cdr ring)) (mod (- (car ring) 1 n) (ring-length ring)))))
 513
 514 ;; Push item onto ring.  The second argument is a ring-variable, not value.
 515 (defun viper-push-onto-ring (item ring-var)
 516   (or (ring-p (eval ring-var))
 517       (set ring-var (make-ring (eval (intern (format "%S-size" ring-var))))))
 518   (or (null item) ; don't push nil
 519       (and (stringp item) (string= item "")) ; or empty strings
 520       (equal item (viper-current-ring-item (eval ring-var))) ; or old stuff
 521       ;; Since viper-set-destructive-command checks if we are inside
 522       ;; viper-repeat, we don't check whether this-command-keys is a `.'.  The
 523       ;; cmd viper-repeat makes a call to the current function only if `.' is
 524       ;; executing a command from the command history.  It doesn't call the
 525       ;; push-onto-ring function if `.' is simply repeating the last
 526       ;; destructive command.  We only check for ESC (which happens when we do
 527       ;; insert with a prefix argument, or if this-command-keys doesn't give
 528       ;; anything meaningful (in that case we don't know what to show to the
 529       ;; user).
 530       (and (eq ring-var 'viper-command-ring)
 531            (string-match "\\([0-9]*\e\\|^[ \t]*$\\|escape\\)"
 532                          (viper-array-to-string (this-command-keys))))
 533       (viper-ring-insert (eval ring-var) item))
 534   )
 535
 536
 537 ;; removing elts from ring seems to break it
 538 (defun viper-cleanup-ring (ring)
 539   (or (< (ring-length ring) 2)
 540       (null (viper-current-ring-item ring))
 541       ;; last and previous equal
 542       (if (equal (viper-current-ring-item ring)
 543                  (viper-current-ring-item ring 1))
 544           (viper-ring-pop ring))))
 545
 546 ;; ring-remove seems to be buggy, so we concocted this for our purposes.
 547 (defun viper-ring-pop (ring)
 548   (let* ((ln (ring-length ring))
 549          (vec (cdr (cdr ring)))
 550          (veclen (length vec))
 551          (hd (car ring))
 552          (idx (max 0 (ring-minus1 hd ln)))
 553          (top-elt (aref vec idx)))
 554
 555         ;; shift elements
 556         (while (< (1+ idx) veclen)
 557           (aset vec idx (aref vec (1+ idx)))
 558           (setq idx (1+ idx)))
 559         (aset vec idx nil)
 560
 561         (setq hd (max 0 (ring-minus1 hd ln)))
 562         (if (= hd (1- ln)) (setq hd 0))
 563         (setcar ring hd) ; move head
 564         (setcar (cdr ring) (max 0 (1- ln))) ; adjust length
 565         top-elt
 566         ))
 567
 568 (defun viper-ring-insert (ring item)
 569   (let* ((ln (ring-length ring))
 570          (vec (cdr (cdr ring)))
 571          (veclen (length vec))
 572          (hd (car ring))
 573          (vecpos-after-hd (if (= hd 0) ln hd))
 574          (idx ln))
 575
 576     (if (= ln veclen)
 577         (progn
 578           (aset vec hd item) ; hd is always 1+ the actual head index in vec
 579           (setcar ring (ring-plus1 hd ln)))
 580       (setcar (cdr ring) (1+ ln))
 581       (setcar ring (ring-plus1 vecpos-after-hd (1+ ln)))
 582       (while (and (>= idx vecpos-after-hd) (> ln 0))
 583         (aset vec idx (aref vec (1- idx)))
 584         (setq idx (1- idx)))
 585       (aset vec vecpos-after-hd item))
 586     item))
 587
 588 \f
 589 ;;; String utilities
 590
 591 ;; If STRING is longer than MAX-LEN, truncate it and print ...... instead
 592 ;; PRE-STRING is a string to prepend to the abbrev string.
 593 ;; POST-STRING is a string to append to the abbrev string.
 594 ;; ABBREV_SIGN is a string to be inserted before POST-STRING
 595 ;; if the orig string was truncated.
 596 (defun viper-abbreviate-string (string max-len
 597                                      pre-string post-string abbrev-sign)
 598   (let (truncated-str)
 599     (setq truncated-str
 600           (if (stringp string)
 601               (substring string 0 (min max-len (length string)))))
 602     (cond ((null truncated-str) "")
 603           ((> (length string) max-len)
 604            (format "%s%s%s%s"
 605                    pre-string truncated-str abbrev-sign post-string))
 606           (t (format "%s%s%s" pre-string truncated-str post-string)))))
 607
 608 ;; tells if we are over a whitespace-only line
 609 (defsubst viper-over-whitespace-line ()
 610   (save-excursion
 611     (beginning-of-line)
 612     (looking-at "^[ \t]*$")))
 613
 614 \f
 615 ;;; Saving settings in custom file
 616
 617 ;; Save the current setting of VAR in CUSTOM-FILE.
 618 ;; If given, MESSAGE is a message to be displayed after that.
 619 ;; This message is erased after 2 secs, if erase-msg is non-nil.
 620 ;; Arguments: var message custom-file &optional erase-message
 621 (defun viper-save-setting (var message custom-file &optional erase-msg)
 622   (let* ((var-name (symbol-name var))
 623          (var-val (if (boundp var) (eval var)))
 624          (regexp (format "^[^;]*%s[ \t\n]*[a-zA-Z---_']*[ \t\n)]" var-name))
 625          (buf (find-file-noselect (substitute-in-file-name custom-file)))
 626         )
 627     (message message)
 628     (save-excursion
 629       (set-buffer buf)
 630       (goto-char (point-min))
 631       (if (re-search-forward regexp nil t)
 632           (let ((reg-end (1- (match-end 0))))
 633             (search-backward var-name)
 634             (delete-region (match-beginning 0) reg-end)
 635             (goto-char (match-beginning 0))
 636             (insert (format "%s  '%S" var-name var-val)))
 637         (goto-char (point-max))
 638         (if (not (bolp)) (insert "\n"))
 639         (insert (format "(setq %s '%S)\n" var-name var-val)))
 640       (save-buffer))
 641       (kill-buffer buf)
 642       (if erase-msg
 643           (progn
 644             (sit-for 2)
 645             (message "")))
 646       ))
 647
 648 ;; Save STRING in CUSTOM-FILE.  If PATTERN is non-nil, remove strings that
 649 ;; match this pattern.
 650 (defun viper-save-string-in-file (string custom-file &optional pattern)
 651   (let ((buf (find-file-noselect (substitute-in-file-name custom-file))))
 652     (save-excursion
 653       (set-buffer buf)
 654       (let (buffer-read-only)
 655         (goto-char (point-min))
 656         (if pattern (delete-matching-lines pattern))
 657         (goto-char (point-max))
 658         (if string (insert string))
 659         (save-buffer)))
 660     (kill-buffer buf)
 661     ))
 662
 663
 664 ;; define remote file test
 665 (defun viper-file-remote-p (file-name)
 666   (file-remote-p file-name))
 667
 668
 669 ;; This is a simple-minded check for whether a file is under version control.
 670 ;; If file,v exists but file doesn't, this file is considered to be not checked
 671 ;; in and not checked out for the purpose of patching (since patch won't be
 672 ;; able to read such a file anyway).
 673 ;; FILE is a string representing file name
 674 ;;(defun viper-file-under-version-control (file)
 675 ;;  (let* ((filedir (file-name-directory file))
 676 ;;       (file-nondir (file-name-nondirectory file))
 677 ;;       (trial (concat file-nondir ",v"))
 678 ;;       (full-trial (concat filedir trial))
 679 ;;       (full-rcs-trial (concat filedir "RCS/" trial)))
 680 ;;    (and (stringp file)
 681 ;;       (file-exists-p file)
 682 ;;       (or
 683 ;;        (and
 684 ;;         (file-exists-p full-trial)
 685 ;;         ;; in FAT FS, `file,v' and `file' may turn out to be the same!
 686 ;;         ;; don't be fooled by this!
 687 ;;         (not (equal (file-attributes file)
 688 ;;                     (file-attributes full-trial))))
 689 ;;        ;; check if a version is in RCS/ directory
 690 ;;        (file-exists-p full-rcs-trial)))
 691 ;;       ))
 692
 693
 694 (defsubst viper-file-checked-in-p (file)
 695   (and (featurep 'vc-hooks)
 696        ;; CVS files are considered not checked in
 697        (not (memq (vc-backend file) '(nil CVS)))
 698        (if (fboundp 'vc-state)
 699            (and
 700              (not (memq (vc-state file) '(edited needs-merge)))
 701              (not (stringp (vc-state file))))
 702          ;; XEmacs has no vc-state
 703          (not (vc-locking-user file)))
 704        ))
 705
 706 ;; checkout if visited file is checked in
 707 (defun viper-maybe-checkout (buf)
 708   (let ((file (expand-file-name (buffer-file-name buf)))
 709         (checkout-function (key-binding "\C-x\C-q")))
 710     (if (and (viper-file-checked-in-p file)
 711              (or (beep 1) t)
 712              (y-or-n-p
 713               (format
 714                "File %s is checked in.  Check it out? "
 715                (viper-abbreviate-file-name file))))
 716         (with-current-buffer buf
 717           (command-execute checkout-function)))))
 718
 719
 720
 721 \f
 722 ;;; Overlays
 723 (defun viper-put-on-search-overlay (beg end)
 724   (if (viper-overlay-p viper-search-overlay)
 725       (viper-move-overlay viper-search-overlay beg end)
 726     (setq viper-search-overlay (viper-make-overlay beg end (current-buffer)))
 727     (viper-overlay-put
 728      viper-search-overlay 'priority viper-search-overlay-priority))
 729   (viper-overlay-put viper-search-overlay 'face viper-search-face))
 730
 731 ;; Search
 732
 733 (defun viper-flash-search-pattern ()
 734   (if (not (viper-has-face-support-p))
 735       nil
 736     (viper-put-on-search-overlay (match-beginning 0) (match-end 0))
 737     (sit-for 2)
 738     (viper-overlay-put viper-search-overlay 'face nil)))
 739
 740 (defun viper-hide-search-overlay ()
 741   (if (not (viper-overlay-p viper-search-overlay))
 742       (progn
 743         (setq viper-search-overlay
 744               (viper-make-overlay (point-min) (point-min) (current-buffer)))
 745         (viper-overlay-put
 746          viper-search-overlay 'priority viper-search-overlay-priority)))
 747   (viper-overlay-put viper-search-overlay 'face nil))
 748
 749 ;; Replace state
 750
 751 (defsubst viper-move-replace-overlay (beg end)
 752   (viper-move-overlay viper-replace-overlay beg end))
 753
 754 (defun viper-set-replace-overlay (beg end)
 755   (if (viper-overlay-live-p viper-replace-overlay)
 756       (viper-move-replace-overlay beg end)
 757     (setq viper-replace-overlay (viper-make-overlay beg end (current-buffer)))
 758     ;; never detach
 759     (viper-overlay-put
 760      viper-replace-overlay (if viper-emacs-p 'evaporate 'detachable) nil)
 761     (viper-overlay-put
 762      viper-replace-overlay 'priority viper-replace-overlay-priority)
 763     ;; If Emacs will start supporting overlay maps, as it currently supports
 764     ;; text-property maps, we could do away with viper-replace-minor-mode and
 765     ;; just have keymap attached to replace overlay.
 766     ;;(viper-overlay-put
 767     ;; viper-replace-overlay
 768     ;; (if viper-xemacs-p 'keymap 'local-map)
 769     ;; viper-replace-map)
 770     )
 771   (if (viper-has-face-support-p)
 772       (viper-overlay-put
 773        viper-replace-overlay 'face viper-replace-overlay-face))
 774   (viper-save-cursor-color 'before-replace-mode)
 775   (viper-change-cursor-color viper-replace-overlay-cursor-color)
 776   )
 777
 778
 779 (defun viper-set-replace-overlay-glyphs (before-glyph after-glyph)
 780   (or (viper-overlay-live-p viper-replace-overlay)
 781       (viper-set-replace-overlay (point-min) (point-min)))
 782   (if (or (not (viper-has-face-support-p))
 783           viper-use-replace-region-delimiters)
 784       (let ((before-name (if viper-xemacs-p 'begin-glyph 'before-string))
 785             (after-name (if viper-xemacs-p 'end-glyph 'after-string)))
 786         (viper-overlay-put viper-replace-overlay before-name before-glyph)
 787         (viper-overlay-put viper-replace-overlay after-name after-glyph))))
 788
 789 (defun viper-hide-replace-overlay ()
 790   (viper-set-replace-overlay-glyphs nil nil)
 791   (viper-restore-cursor-color 'after-replace-mode)
 792   (viper-restore-cursor-color 'after-insert-mode)
 793   (if (viper-has-face-support-p)
 794       (viper-overlay-put viper-replace-overlay 'face nil)))
 795
 796
 797 (defsubst viper-replace-start ()
 798   (viper-overlay-start viper-replace-overlay))
 799 (defsubst viper-replace-end ()
 800   (viper-overlay-end viper-replace-overlay))
 801
 802
 803 ;; Minibuffer
 804
 805 (defun viper-set-minibuffer-overlay ()
 806   (viper-check-minibuffer-overlay)
 807   (if (viper-has-face-support-p)
 808       (progn
 809         (viper-overlay-put
 810          viper-minibuffer-overlay 'face viper-minibuffer-current-face)
 811         (viper-overlay-put
 812          viper-minibuffer-overlay 'priority viper-minibuffer-overlay-priority)
 813         ;; never detach
 814         (viper-overlay-put
 815          viper-minibuffer-overlay
 816          (if viper-emacs-p 'evaporate 'detachable)
 817          nil)
 818         ;; make viper-minibuffer-overlay open-ended
 819         ;; In emacs, it is made open ended at creation time
 820         (if viper-xemacs-p
 821             (progn
 822               (viper-overlay-put viper-minibuffer-overlay 'start-open nil)
 823               (viper-overlay-put viper-minibuffer-overlay 'end-open nil)))
 824         )))
 825
 826 (defun viper-check-minibuffer-overlay ()
 827   (if (viper-overlay-live-p viper-minibuffer-overlay)
 828       (viper-move-overlay
 829        viper-minibuffer-overlay
 830        (if (fboundp 'minibuffer-prompt-end) (minibuffer-prompt-end) 1)
 831        (1+ (buffer-size)))
 832     (setq viper-minibuffer-overlay
 833           (if viper-xemacs-p
 834               (viper-make-overlay 1 (1+ (buffer-size)) (current-buffer))
 835             ;; make overlay open-ended
 836             (viper-make-overlay
 837              (if (fboundp 'minibuffer-prompt-end) (minibuffer-prompt-end) 1)
 838              (1+ (buffer-size))
 839              (current-buffer) nil 'rear-advance)))
 840     ))
 841
 842
 843 (defsubst viper-is-in-minibuffer ()
 844   (save-match-data
 845     (string-match "\*Minibuf-" (buffer-name))))
 846
 847
 848 \f
 849 ;;; XEmacs compatibility
 850
 851 (defun viper-abbreviate-file-name (file)
 852   (viper-cond-compile-for-xemacs-or-emacs
 853    ;; XEmacs requires addl argument
 854    (abbreviate-file-name file t)
 855    ;; emacs
 856    (abbreviate-file-name file)
 857    ))
 858
 859 ;; Sit for VAL milliseconds.  XEmacs doesn't support the millisecond arg
 860 ;; in sit-for, so this function smoothes out the differences.
 861 (defsubst viper-sit-for-short (val &optional nodisp)
 862   (if viper-xemacs-p
 863       (sit-for (/ val 1000.0) nodisp)
 864     (sit-for 0 val nodisp)))
 865
 866 ;; EVENT may be a single event of a sequence of events
 867 (defsubst viper-ESC-event-p (event)
 868   (let ((ESC-keys '(?\e (control \[) escape))
 869         (key (viper-event-key event)))
 870     (member key ESC-keys)))
 871
 872 ;; checks if object is a marker, has a buffer, and points to within that buffer
 873 (defun viper-valid-marker (marker)
 874   (if (and (markerp marker) (marker-buffer marker))
 875       (let ((buf (marker-buffer marker))
 876             (pos (marker-position marker)))
 877         (save-excursion
 878           (set-buffer buf)
 879           (and (<= pos (point-max)) (<= (point-min) pos))))))
 880
 881 (defsubst viper-mark-marker ()
 882   (viper-cond-compile-for-xemacs-or-emacs
 883    (mark-marker t) ; xemacs
 884    (mark-marker) ; emacs
 885    ))
 886
 887 ;; like (set-mark-command nil) but doesn't push twice, if (car mark-ring)
 888 ;; is the same as (mark t).
 889 (defsubst viper-set-mark-if-necessary ()
 890   (setq mark-ring (delete (viper-mark-marker) mark-ring))
 891   (set-mark-command nil)
 892   (setq viper-saved-mark (point)))
 893
 894 ;; In transient mark mode (zmacs mode), it is annoying when regions become
 895 ;; highlighted due to Viper's pushing marks.  So, we deactivate marks, unless
 896 ;; the user explicitly wants highlighting, e.g., by hitting '' or ``
 897 (defun viper-deactivate-mark ()
 898   (viper-cond-compile-for-xemacs-or-emacs
 899    (zmacs-deactivate-region)
 900    (deactivate-mark)
 901    ))
 902
 903 (defsubst viper-leave-region-active ()
 904   (viper-cond-compile-for-xemacs-or-emacs
 905    (setq zmacs-region-stays t)
 906    nil
 907    ))
 908
 909 ;; Check if arg is a valid character for register
 910 ;; TYPE is a list that can contain `letter', `Letter', and `digit'.
 911 ;; Letter means lowercase letters, Letter means uppercase letters, and
 912 ;; digit means digits from 1 to 9.
 913 ;; If TYPE is nil, then down/uppercase letters and digits are allowed.
 914 (defun viper-valid-register (reg &optional type)
 915   (or type (setq type '(letter Letter digit)))
 916   (or (if (memq 'letter type)
 917           (and (<= ?a reg) (<= reg ?z)))
 918       (if (memq 'digit type)
 919           (and (<= ?1 reg) (<= reg ?9)))
 920       (if (memq 'Letter type)
 921           (and (<= ?A reg) (<= reg ?Z)))
 922       ))
 923
 924
 925
 926 ;; it is suggested that an event must be copied before it is assigned to
 927 ;; last-command-event in XEmacs
 928 (defun viper-copy-event (event)
 929   (viper-cond-compile-for-xemacs-or-emacs
 930    (copy-event event) ; xemacs
 931    event ; emacs
 932    ))
 933
 934 ;; Uses different timeouts for ESC-sequences and others
 935 (defsubst viper-fast-keysequence-p ()
 936   (not (viper-sit-for-short
 937         (if (viper-ESC-event-p last-input-event)
 938             viper-ESC-keyseq-timeout
 939           viper-fast-keyseq-timeout)
 940         t)))
 941
 942 ;; like read-event, but in XEmacs also try to convert to char, if possible
 943 (defun viper-read-event-convert-to-char ()
 944   (let (event)
 945     (viper-cond-compile-for-xemacs-or-emacs
 946      (progn
 947        (setq event (next-command-event))
 948        (or (event-to-character event)
 949            event))
 950      (read-event)
 951      )
 952     ))
 953
 954 ;; Viperized read-key-sequence
 955 (defun viper-read-key-sequence (prompt &optional continue-echo)
 956   (let (inhibit-quit event keyseq)
 957     (setq keyseq (read-key-sequence prompt continue-echo))
 958     (setq event (if viper-xemacs-p
 959                     (elt keyseq 0) ; XEmacs returns vector of events
 960                   (elt (listify-key-sequence keyseq) 0)))
 961     (if (viper-ESC-event-p event)
 962         (let (unread-command-events)
 963           (if (viper-fast-keysequence-p)
 964               (let ((viper-vi-global-user-minor-mode  nil)
 965                     (viper-vi-local-user-minor-mode  nil)
 966                     (viper-vi-intercept-minor-mode nil)
 967                     (viper-insert-intercept-minor-mode nil)
 968                     (viper-replace-minor-mode nil) ; actually unnecessary
 969                     (viper-insert-global-user-minor-mode  nil)
 970                     (viper-insert-local-user-minor-mode  nil))
 971                 ;; Note: set unread-command-events only after testing for fast
 972                 ;; keysequence. Otherwise, viper-fast-keysequence-p will be
 973                 ;; always t -- whether there is anything after ESC or not
 974                 (viper-set-unread-command-events keyseq)
 975                 (setq keyseq (read-key-sequence nil)))
 976             (viper-set-unread-command-events keyseq)
 977             (setq keyseq (read-key-sequence nil)))))
 978     keyseq))
 979
 980
 981 ;; This function lets function-key-map convert key sequences into logical
 982 ;; keys.  This does a better job than viper-read-event when it comes to kbd
 983 ;; macros, since it enables certain macros to be shared between X and TTY modes
 984 ;; by correctly mapping key sequences for Left/Right/... (one an ascii
 985 ;; terminal) into logical keys left, right, etc.
 986 (defun viper-read-key ()
 987   (let ((overriding-local-map viper-overriding-map)
 988         (inhibit-quit t)
 989         help-char key)
 990     (use-global-map viper-overriding-map)
 991     (unwind-protect
 992         (setq key (elt (viper-read-key-sequence nil) 0))
 993       (use-global-map global-map))
 994     key))
 995
 996
 997 ;; Emacs has a bug in eventp, which causes (eventp nil) to return (nil)
 998 ;; instead of nil, if '(nil) was previously inadvertently assigned to
 999 ;; unread-command-events
1000 (defun viper-event-key (event)
1001   (or (and event (eventp event))
1002       (error "viper-event-key: Wrong type argument, eventp, %S" event))
1003   (when (viper-cond-compile-for-xemacs-or-emacs
1004          (or (key-press-event-p event) (mouse-event-p event)) ; xemacs
1005          t ; emacs
1006          )
1007     (let ((mod (event-modifiers event))
1008           basis)
1009       (setq basis
1010             (viper-cond-compile-for-xemacs-or-emacs
1011              ;; XEmacs
1012              (cond ((key-press-event-p event)
1013                     (event-key event))
1014                    ((button-event-p event)
1015                     (concat "mouse-" (prin1-to-string (event-button event))))
1016                    (t
1017                     (error "viper-event-key: Unknown event, %S" event)))
1018              ;; Emacs doesn't handle capital letters correctly, since
1019              ;; \S-a isn't considered the same as A (it behaves as
1020              ;; plain `a' instead).  So we take care of this here
1021              (cond ((and (viper-characterp event) (<= ?A event) (<= event ?Z))
1022                     (setq mod nil
1023                           event event))
1024                    ;; Emacs has the oddity whereby characters 128+char
1025                    ;; represent M-char *if* this appears inside a string.
1026                    ;; So, we convert them manually to (meta char).
1027                    ((and (viper-characterp event)
1028                          (< ?\C-? event) (<= event 255))
1029                     (setq mod '(meta)
1030                           event (- event ?\C-? 1)))
1031                    ((and (null mod) (eq event 'return))
1032                     (setq event ?\C-m))
1033                    ((and (null mod) (eq event 'space))
1034                     (setq event ?\ ))
1035                    ((and (null mod) (eq event 'delete))
1036                     (setq event ?\C-?))
1037                    ((and (null mod) (eq event 'backspace))
1038                     (setq event ?\C-h))
1039                    (t (event-basic-type event)))
1040              ) ; viper-cond-compile-for-xemacs-or-emacs
1041             )
1042       (if (viper-characterp basis)
1043           (setq basis
1044                 (if (viper= basis ?\C-?)
1045                     (list 'control '\?) ; taking care of an emacs bug
1046                   (intern (char-to-string basis)))))
1047       (if mod
1048           (append mod (list basis))
1049         basis))))
1050
1051 (defun viper-key-to-emacs-key (key)
1052   (let (key-name char-p modifiers mod-char-list base-key base-key-name)
1053     (cond (viper-xemacs-p key)
1054
1055           ((symbolp key)
1056            (setq key-name (symbol-name key))
1057            (cond ((= (length key-name) 1) ; character event
1058                   (string-to-char key-name))
1059                  ;; Emacs doesn't recognize `return' and `escape' as events on
1060                  ;; dumb terminals, so we translate them into characters
1061                  ((and viper-emacs-p (not (viper-window-display-p))
1062                        (string= key-name "return"))
1063                   ?\C-m)
1064                  ((and viper-emacs-p (not (viper-window-display-p))
1065                        (string= key-name "escape"))
1066                   ?\e)
1067                  ;; pass symbol-event as is
1068                  (t key)))
1069
1070           ((listp key)
1071            (setq modifiers (subseq key 0 (1- (length key)))
1072                  base-key (viper-seq-last-elt key)
1073                  base-key-name (symbol-name base-key)
1074                  char-p (= (length base-key-name) 1))
1075            (setq mod-char-list
1076                  (mapcar
1077                   '(lambda (elt) (upcase (substring (symbol-name elt) 0 1)))
1078                   modifiers))
1079            (if char-p
1080                (setq key-name
1081                      (car (read-from-string
1082                            (concat
1083                             "?\\"
1084                             (mapconcat 'identity mod-char-list "-\\")
1085                             "-"
1086                             base-key-name))))
1087              (setq key-name
1088                    (intern
1089                     (concat
1090                      (mapconcat 'identity mod-char-list "-")
1091                      "-"
1092                      base-key-name))))))
1093     ))
1094
1095
1096 ;; LIS is assumed to be a list of events of characters
1097 (defun viper-eventify-list-xemacs (lis)
1098   (mapcar
1099    (lambda (elt)
1100      (cond ((viper-characterp elt) (character-to-event elt))
1101            ((eventp elt)  elt)
1102            (t (error
1103                "viper-eventify-list-xemacs: can't convert to event, %S"
1104                elt))))
1105    lis))
1106
1107
1108 ;; Smoothes out the difference between Emacs' unread-command-events
1109 ;; and XEmacs unread-command-event.  Arg is a character, an event, a list of
1110 ;; events or a sequence of keys.
1111 ;;
1112 ;; Due to the way unread-command-events in Emacs (not XEmacs), a non-event
1113 ;; symbol in unread-command-events list may cause Emacs to turn this symbol
1114 ;; into an event.  Below, we delete nil from event lists, since nil is the most
1115 ;; common symbol that might appear in this wrong context.
1116 (defun viper-set-unread-command-events (arg)
1117   (if viper-emacs-p
1118       (setq
1119        unread-command-events
1120        (let ((new-events
1121               (cond ((eventp arg) (list arg))
1122                     ((listp arg) arg)
1123                     ((sequencep arg)
1124                      (listify-key-sequence arg))
1125                     (t (error
1126                         "viper-set-unread-command-events: Invalid argument, %S"
1127                         arg)))))
1128          (if (not (eventp nil))
1129              (setq new-events (delq nil new-events)))
1130          (append new-events unread-command-events)))
1131     ;; XEmacs
1132     (setq
1133      unread-command-events
1134      (append
1135       (cond ((viper-characterp arg) (list (character-to-event arg)))
1136             ((eventp arg)  (list arg))
1137             ((stringp arg) (mapcar 'character-to-event arg))
1138             ((vectorp arg) (append arg nil)) ; turn into list
1139             ((listp arg) (viper-eventify-list-xemacs arg))
1140             (t (error
1141                 "viper-set-unread-command-events: Invalid argument, %S" arg)))
1142       unread-command-events))))
1143
1144
1145 ;; Check if vec is a vector of key-press events representing characters
1146 ;; XEmacs only
1147 (defun viper-event-vector-p (vec)
1148   (and (vectorp vec)
1149        (eval (cons 'and (mapcar '(lambda (elt) (if (eventp elt) t)) vec)))))
1150
1151
1152 ;; check if vec is a vector of character symbols
1153 (defun viper-char-symbol-sequence-p (vec)
1154   (and
1155    (sequencep vec)
1156    (eval
1157     (cons 'and
1158           (mapcar (lambda (elt)
1159                     (and (symbolp elt) (= (length (symbol-name elt)) 1)))
1160                   vec)))))
1161
1162
1163 (defun viper-char-array-p (array)
1164   (eval (cons 'and (mapcar 'viper-characterp array))))
1165
1166
1167 ;; Args can be a sequence of events, a string, or a Viper macro.  Will try to
1168 ;; convert events to keys and, if all keys are regular printable
1169 ;; characters, will return a string.  Otherwise, will return a string
1170 ;; representing a vector of converted events.  If the input was a Viper macro,
1171 ;; will return a string that represents this macro as a vector.
1172 (defun viper-array-to-string (event-seq)
1173   (let (temp temp2)
1174     (cond ((stringp event-seq) event-seq)
1175           ((viper-event-vector-p event-seq)
1176             (setq temp (mapcar 'viper-event-key event-seq))
1177             (cond ((viper-char-symbol-sequence-p temp)
1178                    (mapconcat 'symbol-name temp ""))
1179                   ((and (viper-char-array-p
1180                          (setq temp2 (mapcar 'viper-key-to-character temp))))
1181                    (mapconcat 'char-to-string temp2 ""))
1182                   (t (prin1-to-string (vconcat temp)))))
1183           ((viper-char-symbol-sequence-p event-seq)
1184            (mapconcat 'symbol-name event-seq ""))
1185           ((and (vectorp event-seq)
1186                 (viper-char-array-p
1187                  (setq temp (mapcar 'viper-key-to-character event-seq))))
1188            (mapconcat 'char-to-string temp ""))
1189           (t (prin1-to-string event-seq)))))
1190
1191 (defun viper-key-press-events-to-chars (events)
1192   (mapconcat (viper-cond-compile-for-xemacs-or-emacs
1193               (lambda (elt) (char-to-string (event-to-character elt))) ; xemacs
1194               'char-to-string ; emacs
1195               )
1196              events
1197              ""))
1198
1199
1200 (defun viper-read-char-exclusive ()
1201   (let (char
1202         (echo-keystrokes 1))
1203     (while (null char)
1204       (condition-case nil
1205           (setq char (read-char))
1206         (error
1207          ;; skip event if not char
1208          (viper-read-event))))
1209     char))
1210
1211 ;; key is supposed to be in viper's representation, e.g., (control l), a
1212 ;; character, etc.
1213 (defun viper-key-to-character (key)
1214   (cond ((eq key 'space) ?\ )
1215         ((eq key 'delete) ?\C-?)
1216         ((eq key 'return) ?\C-m)
1217         ((eq key 'backspace) ?\C-h)
1218         ((and (symbolp key)
1219               (= 1 (length (symbol-name key))))
1220          (string-to-char (symbol-name key)))
1221         ((and (listp key)
1222               (eq (car key) 'control)
1223               (symbol-name (nth 1 key))
1224               (= 1 (length (symbol-name (nth 1 key)))))
1225          (read (format "?\\C-%s" (symbol-name (nth 1 key)))))
1226         (t key)))
1227
1228
1229 (defun viper-setup-master-buffer (&rest other-files-or-buffers)
1230   "Set up the current buffer as a master buffer.
1231 Arguments become related buffers.  This function should normally be used in
1232 the `Local variables' section of a file."
1233   (setq viper-related-files-and-buffers-ring
1234         (make-ring (1+ (length other-files-or-buffers))))
1235   (mapcar '(lambda (elt)
1236              (viper-ring-insert viper-related-files-and-buffers-ring elt))
1237           other-files-or-buffers)
1238   (viper-ring-insert viper-related-files-and-buffers-ring (buffer-name))
1239   )
1240
1241 ;;; Movement utilities
1242
1243 ;; Characters that should not be considered as part of the word, in reformed-vi
1244 ;; syntax mode.
1245 (defconst viper-non-word-characters-reformed-vi
1246   "!@#$%^&*()-+=|\\~`{}[];:'\",<.>/?")
1247 ;; These are characters that are not to be considered as parts of a word in
1248 ;; Viper.
1249 ;; Set each time state changes and at loading time
1250 (viper-deflocalvar viper-non-word-characters  nil)
1251
1252 ;; must be buffer-local
1253 (viper-deflocalvar viper-ALPHA-char-class "w"
1254   "String of syntax classes characterizing Viper's alphanumeric symbols.
1255 In addition, the symbol `_' may be considered alphanumeric if
1256 `viper-syntax-preference' is `strict-vi' or `reformed-vi'.")
1257
1258 (defconst viper-strict-ALPHA-chars "a-zA-Z0-9_"
1259   "Regexp matching the set of alphanumeric characters acceptable to strict
1260 Vi.")
1261 (defconst viper-strict-SEP-chars " \t\n"
1262   "Regexp matching the set of alphanumeric characters acceptable to strict
1263 Vi.")
1264 (defconst viper-strict-SEP-chars-sans-newline " \t"
1265   "Regexp matching the set of alphanumeric characters acceptable to strict
1266 Vi.")
1267
1268 (defconst viper-SEP-char-class " -"
1269   "String of syntax classes for Vi separators.
1270 Usually contains ` ', linefeed, TAB or formfeed.")
1271
1272
1273 ;; Set Viper syntax classes and related variables according to
1274 ;; `viper-syntax-preference'.
1275 (defun viper-update-syntax-classes (&optional set-default)
1276   (let ((preference (cond ((eq viper-syntax-preference 'emacs)
1277                            "w")   ; Viper words have only Emacs word chars
1278                           ((eq viper-syntax-preference 'extended)
1279                            "w_")  ; Viper words have Emacs word & symbol chars
1280                           (t "w"))) ; Viper words are Emacs words plus `_'
1281         (non-word-chars (cond ((eq viper-syntax-preference 'reformed-vi)
1282                                (viper-string-to-list
1283                                 viper-non-word-characters-reformed-vi))
1284                               (t nil))))
1285     (if set-default
1286         (setq-default viper-ALPHA-char-class preference
1287                       viper-non-word-characters non-word-chars)
1288       (setq viper-ALPHA-char-class preference
1289             viper-non-word-characters non-word-chars))
1290     ))
1291
1292 ;; SYMBOL is used because customize requires it, but it is ignored, unless it
1293 ;; is `nil'.  If nil, use setq.
1294 (defun viper-set-syntax-preference (&optional symbol value)
1295   "Set Viper syntax preference.
1296 If called interactively or if SYMBOL is nil, sets syntax preference in current
1297 buffer.  If called non-interactively, preferably via the customization widget,
1298 sets the default value."
1299   (interactive)
1300   (or value
1301       (setq value
1302             (completing-read
1303              "Viper syntax preference: "
1304              '(("strict-vi") ("reformed-vi") ("extended") ("emacs"))
1305              nil 'require-match)))
1306   (if (stringp value) (setq value (intern value)))
1307   (or (memq value '(strict-vi reformed-vi extended emacs))
1308       (error "Invalid Viper syntax preference, %S" value))
1309   (if symbol
1310       (setq-default viper-syntax-preference value)
1311     (setq viper-syntax-preference value))
1312   (viper-update-syntax-classes))
1313
1314 (defcustom viper-syntax-preference 'reformed-vi
1315   "*Syntax type characterizing Viper's alphanumeric symbols.
1316 Affects movement and change commands that deal with Vi-style words.
1317 Works best when set in the hooks to various major modes.
1318
1319 `strict-vi' means Viper words are (hopefully) exactly as in Vi.
1320
1321 `reformed-vi' means Viper words are like Emacs words \(as determined using
1322 Emacs syntax tables, which are different for different major modes\) with two
1323 exceptions: the symbol `_' is always part of a word and typical Vi non-word
1324 symbols, such as `,',:,\",),{, etc., are excluded.
1325 This behaves very close to `strict-vi', but also works well with non-ASCII
1326 characters from various alphabets.
1327
1328 `extended' means Viper word constituents are symbols that are marked as being
1329 parts of words OR symbols in Emacs syntax tables.
1330 This is most appropriate for major modes intended for editing programs.
1331
1332 `emacs' means Viper words are the same as Emacs words as specified by Emacs
1333 syntax tables.
1334 This option is appropriate if you like Emacs-style words."
1335   :type '(radio (const strict-vi) (const reformed-vi)
1336                  (const extended) (const emacs))
1337   :set 'viper-set-syntax-preference
1338   :group 'viper)
1339 (make-variable-buffer-local 'viper-syntax-preference)
1340
1341
1342 ;; addl-chars are characters to be temporarily considered as alphanumerical
1343 (defun viper-looking-at-alpha (&optional addl-chars)
1344   (or (stringp addl-chars) (setq addl-chars ""))
1345   (if (eq viper-syntax-preference 'reformed-vi)
1346       (setq addl-chars (concat addl-chars "_")))
1347   (let ((char (char-after (point))))
1348     (if char
1349         (if (eq viper-syntax-preference 'strict-vi)
1350             (looking-at (concat "[" viper-strict-ALPHA-chars addl-chars "]"))
1351           (or
1352            ;; or one of the additional chars being asked to include
1353            (viper-memq-char char (viper-string-to-list addl-chars))
1354            (and
1355             ;; not one of the excluded word chars (note:
1356             ;; viper-non-word-characters is a list)
1357             (not (viper-memq-char char viper-non-word-characters))
1358             ;; char of the Viper-word syntax class
1359             (viper-memq-char (char-syntax char)
1360                              (viper-string-to-list viper-ALPHA-char-class))))))
1361     ))
1362
1363 (defun viper-looking-at-separator ()
1364   (let ((char (char-after (point))))
1365     (if char
1366         (if (eq viper-syntax-preference 'strict-vi)
1367             (viper-memq-char char (viper-string-to-list viper-strict-SEP-chars))
1368           (or (eq char ?\n) ; RET is always a separator in Vi
1369               (viper-memq-char (char-syntax char)
1370                                (viper-string-to-list viper-SEP-char-class)))))
1371     ))
1372
1373 (defsubst viper-looking-at-alphasep (&optional addl-chars)
1374   (or (viper-looking-at-separator) (viper-looking-at-alpha addl-chars)))
1375
1376 (defun viper-skip-alpha-forward (&optional addl-chars)
1377   (or (stringp addl-chars) (setq addl-chars ""))
1378   (viper-skip-syntax
1379    'forward
1380    (cond ((eq viper-syntax-preference 'strict-vi)
1381           "")
1382          (t viper-ALPHA-char-class))
1383    (cond ((eq viper-syntax-preference 'strict-vi)
1384           (concat viper-strict-ALPHA-chars addl-chars))
1385          (t addl-chars))))
1386
1387 (defun viper-skip-alpha-backward (&optional addl-chars)
1388   (or (stringp addl-chars) (setq addl-chars ""))
1389   (viper-skip-syntax
1390    'backward
1391    (cond ((eq viper-syntax-preference 'strict-vi)
1392           "")
1393          (t viper-ALPHA-char-class))
1394    (cond ((eq viper-syntax-preference 'strict-vi)
1395           (concat viper-strict-ALPHA-chars addl-chars))
1396          (t addl-chars))))
1397
1398 ;; weird syntax tables may confuse strict-vi style
1399 (defsubst viper-skip-all-separators-forward (&optional within-line)
1400   (if (eq viper-syntax-preference 'strict-vi)
1401       (if within-line
1402           (skip-chars-forward viper-strict-SEP-chars-sans-newline)
1403         (skip-chars-forward viper-strict-SEP-chars))
1404     (viper-skip-syntax 'forward
1405                        viper-SEP-char-class
1406                        (or within-line "\n")
1407                        (if within-line (viper-line-pos 'end)))))
1408 (defsubst viper-skip-all-separators-backward (&optional within-line)
1409   (if (eq viper-syntax-preference 'strict-vi)
1410       (if within-line
1411           (skip-chars-backward viper-strict-SEP-chars-sans-newline)
1412         (skip-chars-backward viper-strict-SEP-chars))
1413     (viper-skip-syntax 'backward
1414                        viper-SEP-char-class
1415                        (or within-line "\n")
1416                        (if within-line (viper-line-pos 'start)))))
1417 (defun viper-skip-nonseparators (direction)
1418   (viper-skip-syntax
1419    direction
1420    (concat "^" viper-SEP-char-class)
1421    nil
1422    (viper-line-pos (if (eq direction 'forward) 'end 'start))))
1423
1424
1425 ;; skip over non-word constituents and non-separators
1426 (defun viper-skip-nonalphasep-forward ()
1427   (if (eq viper-syntax-preference 'strict-vi)
1428       (skip-chars-forward
1429        (concat "^" viper-strict-SEP-chars viper-strict-ALPHA-chars))
1430     (viper-skip-syntax
1431      'forward
1432      (concat "^" viper-ALPHA-char-class viper-SEP-char-class)
1433      ;; Emacs may consider some of these as words, but we don't want them
1434      viper-non-word-characters
1435      (viper-line-pos 'end))))
1436 (defun viper-skip-nonalphasep-backward ()
1437   (if (eq viper-syntax-preference 'strict-vi)
1438       (skip-chars-backward
1439        (concat "^" viper-strict-SEP-chars viper-strict-ALPHA-chars))
1440     (viper-skip-syntax
1441      'backward
1442      (concat "^" viper-ALPHA-char-class viper-SEP-char-class)
1443      ;; Emacs may consider some of these as words, but we don't want them
1444      viper-non-word-characters
1445      (viper-line-pos 'start))))
1446
1447 ;; Skip SYNTAX like skip-syntax-* and ADDL-CHARS like skip-chars-*
1448 ;; Return the number of chars traveled.
1449 ;; Both SYNTAX or ADDL-CHARS can be strings or lists of characters.
1450 ;; When SYNTAX is "w", then viper-non-word-characters are not considered to be
1451 ;; words, even if Emacs syntax table says they are.
1452 (defun viper-skip-syntax (direction syntax addl-chars &optional limit)
1453   (let ((total 0)
1454         (local 1)
1455         (skip-chars-func
1456          (if (eq direction 'forward)
1457              'skip-chars-forward 'skip-chars-backward))
1458         (skip-syntax-func
1459          (if (eq direction 'forward)
1460              'viper-forward-char-carefully 'viper-backward-char-carefully))
1461         char-looked-at syntax-of-char-looked-at negated-syntax)
1462     (setq addl-chars
1463           (cond ((listp addl-chars) (viper-charlist-to-string addl-chars))
1464                 ((stringp addl-chars) addl-chars)
1465                 (t "")))
1466     (setq syntax
1467           (cond ((listp syntax) syntax)
1468                 ((stringp syntax) (viper-string-to-list syntax))
1469                 (t nil)))
1470     (if (memq ?^ syntax) (setq negated-syntax t))
1471
1472     (while (and (not (= local 0))
1473                 (cond ((eq direction 'forward)
1474                        (not (eobp)))
1475                       (t (not (bobp)))))
1476       (setq char-looked-at (viper-char-at-pos direction)
1477             ;; if outside the range, set to nil
1478             syntax-of-char-looked-at (if char-looked-at
1479                                          (char-syntax char-looked-at)))
1480       (setq local
1481             (+ (if (and
1482                     (cond ((and limit (eq direction 'forward))
1483                            (< (point) limit))
1484                           (limit ; backward & limit
1485                            (> (point) limit))
1486                           (t t)) ; no limit
1487                     ;; char under/before cursor has appropriate syntax
1488                     (if negated-syntax
1489                         (not (memq syntax-of-char-looked-at syntax))
1490                       (memq syntax-of-char-looked-at syntax))
1491                     ;; if char-syntax class is "word", make sure it is not one
1492                     ;; of the excluded characters
1493                     (if (and (eq syntax-of-char-looked-at ?w)
1494                              (not negated-syntax))
1495                         (not (viper-memq-char
1496                               char-looked-at viper-non-word-characters))
1497                       t))
1498                    (funcall skip-syntax-func 1)
1499                  0)
1500                (funcall skip-chars-func addl-chars limit)))
1501       (setq total (+ total local)))
1502     total
1503     ))
1504
1505
1506
1507 (provide 'viper-util)
1508
1509
1510 ;;; Local Variables:
1511 ;;; eval: (put 'viper-deflocalvar 'lisp-indent-hook 'defun)
1512 ;;; End:
1513
1514 ;;; arch-tag: 7f023fd5-dd9e-4378-a397-9c179553b0e3
1515 ;;; viper-util.el ends here