lisp/array.el

   1 ;;; array.el --- array editing commands for Gnu Emacs
   2
   3 ;; Copyright (C) 1987, 2000 Free Software Foundation, Inc.
   4
   5 ;; Author David M. Brown
   6 ;; Maintainer: FSF
   7 ;; Keywords: extensions
   8
   9 ;; This file is part of GNU Emacs.
  10
  11 ;; GNU Emacs is free software; you can redistribute it and/or modify
  12 ;; it under the terms of the GNU General Public License as published by
  13 ;; the Free Software Foundation; either version 2, or (at your option)
  14 ;; any later version.
  15
  16 ;; GNU Emacs is distributed in the hope that it will be useful,
  17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 ;; GNU General Public License for more details.
  20
  21 ;; You should have received a copy of the GNU General Public License
  22 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  23 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  24 ;; Boston, MA 02111-1307, USA.
  25
  26 ;;; Commentary:
  27
  28 ;; Commands for editing a buffer interpreted as a rectangular array
  29 ;; or matrix of whitespace-separated strings.  You specify the array
  30 ;; dimensions and some other parameters at startup time.
  31
  32 ;;  Written by dmb%morgoth@harvard.harvard.edu (address is old)
  33 ;;   (David M. Brown at Goldberg-Zoino & Associates, Inc.)
  34 ;;  Thanks to cph@kleph.ai.mit.edu for assistance
  35
  36 ;; To do:
  37 ;;   Smooth initialization process by grokking local variables list
  38 ;;     at end of buffer or parsing buffer using whitespace as delimiters.
  39 ;;   Make 'array-copy-column-right faster.
  40
  41 \f
  42 ;;; Code:
  43
  44 (eval-when-compile
  45   (defvar array-max-column)
  46   (defvar array-columns-per-line)
  47   (defvar array-buffer-column)
  48   (defvar array-line-length)
  49   (defvar array-buffer-line)
  50   (defvar array-lines-per-row)
  51   (defvar array-max-row)
  52   (defvar array-field-width)
  53   (defvar array-row)
  54   (defvar array-column)
  55   (defvar array-rows-numbered)
  56   (defvar array-copy-string)
  57   (defvar array-init-field)
  58   (defvar array-respect-tabs))
  59
  60 ;;; Internal information functions.
  61
  62 (defun array-cursor-in-array-range ()
  63   "Return t if the cursor is in a valid array cell.
  64 Its ok to be on a row number line."
  65   (let ((columns-last-line (% array-max-column array-columns-per-line)))
  66     ;; Requires array-buffer-line and array-buffer-column to be current.
  67     (not (or
  68           ;; The cursor is too far to the right.
  69           (>= array-buffer-column array-line-length)
  70           ;; The cursor is below the last row.
  71           (>= array-buffer-line (* array-lines-per-row array-max-row))
  72           ;; The cursor is on the last line of the row, the line is smaller
  73           ;;  than the others, and the cursor is after the last array column
  74           ;;  on the line.
  75           (and (zerop (% (1+ array-buffer-line) array-lines-per-row))
  76                (not (zerop columns-last-line))
  77                (>= array-buffer-column (* columns-last-line array-field-width)))))))
  78
  79 (defun array-current-row ()
  80   "Return the array row of the field in which the cursor is located."
  81   ;; Requires array-buffer-line and array-buffer-column to be current.
  82   (and (array-cursor-in-array-range)
  83        (1+ (floor array-buffer-line array-lines-per-row))))
  84
  85 (defun array-current-column ()
  86   "Return the array column of the field in which the cursor is located."
  87   ;; Requires array-buffer-line and array-buffer-column to be current.
  88   (and (array-cursor-in-array-range)
  89        ;; It's not okay to be on a row number line.
  90        (not (and array-rows-numbered
  91                  (zerop (% array-buffer-line array-lines-per-row))))
  92        (+
  93         ;; Array columns due to line differences.
  94         (* array-columns-per-line
  95            (if array-rows-numbered
  96                (1- (% array-buffer-line array-lines-per-row))
  97              (% array-buffer-line array-lines-per-row)))
  98         ;; Array columns on the current line.
  99         (1+ (floor array-buffer-column array-field-width)))))
 100
 101 (defun array-update-array-position (&optional a-row a-column)
 102   "Set `array-row' and `array-column' to their current values.
 103 Set them to the optional arguments A-ROW and A-COLUMN if those are supplied."
 104   ;; Requires that array-buffer-line and array-buffer-column be current.
 105   (setq array-row (or a-row (array-current-row))
 106         array-column (or a-column (array-current-column))))
 107
 108 (defun array-update-buffer-position ()
 109   "Set array-buffer-line and array-buffer-column to their current values."
 110   (setq array-buffer-line (current-line)
 111         array-buffer-column (current-column)))
 112
 113 \f
 114
 115 ;;; Information commands.
 116
 117 (defun array-what-position ()
 118   "Display the row and column in which the cursor is positioned."
 119   (interactive)
 120   (let ((array-buffer-line (current-line))
 121         (array-buffer-column (current-column)))
 122     (message "Array row: %s  Array column: %s"
 123              (prin1-to-string (array-current-row))
 124              (prin1-to-string (array-current-column)))))
 125
 126 (defun array-display-local-variables ()
 127   "Display the current state of the local variables in the minibuffer."
 128   (interactive)
 129   (let ((buf (buffer-name (current-buffer))))
 130     (with-output-to-temp-buffer "*Local Variables*"
 131       (buffer-disable-undo standard-output)
 132       (terpri)
 133       (princ (format " Buffer:             %s\n\n" buf))
 134       (princ (format "  max-row:           %s\n"
 135                      (prin1-to-string array-max-row)))
 136       (princ (format "  max-column:        %s\n"
 137                      (prin1-to-string array-max-column)))
 138       (princ (format "  columns-per-line:  %s\n"
 139                      (prin1-to-string array-columns-per-line)))
 140       (princ (format "  field-width:       %s\n"
 141                      (prin1-to-string array-field-width)))
 142       (princ (format "  rows-numbered:     %s\n"
 143                      (prin1-to-string array-rows-numbered)))
 144       (princ (format "  lines-per-row:     %s\n"
 145                      (prin1-to-string array-lines-per-row)))
 146       (princ (format "  line-length:       %s\n"
 147                      (prin1-to-string array-line-length))))))
 148
 149 \f
 150
 151 ;;; Internal movement functions.
 152
 153 (defun array-beginning-of-field (&optional go-there)
 154    "Return the column of the beginning of the current field.
 155 Optional argument GO-THERE, if non-nil, means go there too."
 156    ;; Requires that array-buffer-column be current.
 157    (let ((goal-column (- array-buffer-column (% array-buffer-column array-field-width))))
 158      (if go-there
 159          (move-to-column-untabify goal-column)
 160        goal-column)))
 161
 162 (defun array-end-of-field (&optional go-there)
 163   "Return the column of the end of the current array field.
 164 If optional argument GO-THERE is non-nil, go there too."
 165   ;; Requires that array-buffer-column be current.
 166   (let ((goal-column (+ (- array-buffer-column (% array-buffer-column array-field-width))
 167                         array-field-width)))
 168     (if go-there
 169         (move-to-column-untabify goal-column)
 170       goal-column)))
 171
 172 (defun array-move-to-cell (a-row a-column)
 173   "Move to array row A-ROW and array column A-COLUMN.
 174 Leave point at the beginning of the field and return the new buffer column."
 175   (let ((goal-line (+ (* array-lines-per-row (1- a-row))
 176                       (if array-rows-numbered 1 0)
 177                       (floor (1- a-column) array-columns-per-line)))
 178         (goal-column (* array-field-width (% (1- a-column) array-columns-per-line))))
 179     (goto-char (point-min))
 180     (forward-line goal-line)
 181     (move-to-column-untabify goal-column)))
 182
 183 (defun array-move-to-row (a-row)
 184   "Move to array row A-ROW preserving the current array column.
 185 Leave point at the beginning of the field and return the new array row."
 186   ;; Requires that array-buffer-line and array-buffer-column be current.
 187   (let ((goal-line (+ (* array-lines-per-row (1- a-row))
 188                       (% array-buffer-line array-lines-per-row)))
 189         (goal-column (- array-buffer-column (% array-buffer-column array-field-width))))
 190     (forward-line (- goal-line array-buffer-line))
 191     (move-to-column-untabify goal-column)
 192     a-row))
 193
 194 (defun array-move-to-column (a-column)
 195   "Move to array column A-COLUMN preserving the current array row.
 196 Leave point at the beginning of the field and return the new array column."
 197   ;; Requires that array-buffer-line and array-buffer-column be current.
 198   (let ((goal-line (+ (- array-buffer-line (% array-buffer-line array-lines-per-row))
 199                       (if array-rows-numbered 1 0)
 200                       (floor (1- a-column) array-columns-per-line)))
 201         (goal-column (* array-field-width (% (1- a-column) array-columns-per-line))))
 202     (forward-line (- goal-line array-buffer-line))
 203     (move-to-column-untabify goal-column)
 204     a-column))
 205
 206 (defun array-move-one-row (sign)
 207   "Move one array row in direction SIGN (1 or -1).
 208 Leave point at the beginning of the field and return the new array row.
 209 If requested to move beyond the array bounds, signal an error."
 210   ;; Requires that array-buffer-line and array-buffer-column be current.
 211   (let ((goal-column (array-beginning-of-field))
 212         (array-row (or (array-current-row)
 213                        (error "Cursor is not in a valid array cell"))))
 214     (cond ((and (= array-row array-max-row) (= sign 1))
 215            (error "End of array"))
 216           ((and (= array-row 1) (= sign -1))
 217            (error "Beginning of array"))
 218           (t
 219            (progn
 220              (forward-line (* sign array-lines-per-row))
 221              (move-to-column-untabify goal-column)
 222              (+ array-row sign))))))
 223
 224 (defun array-move-one-column (sign)
 225   "Move one array column in direction SIGN (1 or -1).
 226 Leave point at the beginning of the field and return the new array column.
 227 If requested to move beyond the array bounds, signal an error."
 228   ;; Requires that array-buffer-line and array-buffer-column be current.
 229   (let ((array-column (or (array-current-column)
 230                       (error "Cursor is not in a valid array cell"))))
 231     (cond ((and (= array-column array-max-column) (= sign 1))
 232            (error "End of array"))
 233           ((and (= array-column 1) (= sign -1))
 234            (error "Beginning of array"))
 235           (t
 236            (cond
 237             ;; Going backward from first column on the line.
 238             ((and (= sign -1) (= 1 (% array-column array-columns-per-line)))
 239              (forward-line -1)
 240              (move-to-column-untabify
 241               (* array-field-width (1- array-columns-per-line))))
 242             ;; Going forward from last column on the line.
 243             ((and (= sign 1) (zerop (% array-column array-columns-per-line)))
 244              (forward-line 1))
 245             ;; Somewhere in the middle of the line.
 246             (t
 247              (move-to-column-untabify (+ (array-beginning-of-field)
 248                                          (* array-field-width sign)))))
 249            (+ array-column sign)))))
 250
 251 (defun array-normalize-cursor ()
 252   "Move the cursor to the first non-whitespace character in the field.
 253 If necessary, scroll horizontally to keep the cursor in view."
 254   ;; Assumes point is at the beginning of the field.
 255   (let ((array-buffer-column (current-column)))
 256     (skip-chars-forward " \t"
 257                         (1- (save-excursion (array-end-of-field t) (point))))
 258     (array-maybe-scroll-horizontally)))
 259
 260 (defun array-maybe-scroll-horizontally ()
 261   "If necessary, scroll horizontally to keep the cursor in view."
 262   ;; This is only called from array-normalize-cursor so
 263   ;;  array-buffer-column will always be current.
 264   (let ((w-hscroll (window-hscroll))
 265         (w-width (window-width)))
 266     (cond
 267      ((and (>= array-buffer-column w-hscroll)
 268            (<= array-buffer-column (+ w-hscroll w-width)))
 269       ;; It's already visible.  Do nothing.
 270       nil)
 271      ((> array-buffer-column (+ w-hscroll w-width))
 272       ;; It's to the right.  Scroll left.
 273       (scroll-left (- (- array-buffer-column w-hscroll)
 274                       (/ w-width 2))))
 275      (t
 276       ;; It's to the left.  Scroll right.
 277       (scroll-right (+ (- w-hscroll array-buffer-column)
 278                        (/ w-width 2)))))))
 279
 280 \f
 281
 282 ;;; Movement commands.
 283
 284 (defun array-next-row (&optional arg)
 285   "Move down one array row, staying in the current array column.
 286 If optional ARG is given, move down ARG array rows."
 287   (interactive "p")
 288   (let ((array-buffer-line (current-line))
 289         (array-buffer-column (current-column)))
 290     (if (= (abs arg) 1)
 291         (array-move-one-row arg)
 292       (array-move-to-row
 293        (limit-index (+ (or (array-current-row)
 294                            (error "Cursor is not in an array cell"))
 295                        arg)
 296                     array-max-row))))
 297   (array-normalize-cursor))
 298
 299 (defun array-previous-row (&optional arg)
 300   "Move up one array row, staying in the current array column.
 301 If optional ARG is given, move up ARG array rows."
 302   (interactive "p")
 303   (array-next-row (- arg)))
 304
 305 (defun array-forward-column (&optional arg)
 306   "Move forward one field, staying in the current array row.
 307 If optional ARG is given, move forward ARG array columns.
 308 If necessary, keep the cursor in the window by scrolling right or left."
 309   (interactive "p")
 310   (let ((array-buffer-line (current-line))
 311         (array-buffer-column (current-column)))
 312     (if (= (abs arg) 1)
 313         (array-move-one-column arg)
 314       (array-move-to-column
 315        (limit-index (+ (or (array-current-column)
 316                            (error "Cursor is not in an array cell"))
 317                        arg)
 318                     array-max-column))))
 319   (array-normalize-cursor))
 320
 321 (defun array-backward-column (&optional arg)
 322   "Move backward one field, staying in the current array row.
 323 If optional ARG is given, move backward ARG array columns.
 324 If necessary, keep the cursor in the window by scrolling right or left."
 325   (interactive "p")
 326   (array-forward-column (- arg)))
 327
 328 (defun array-goto-cell (a-row a-column)
 329   "Go to array row A-ROW and array column A-COLUMN."
 330   (interactive "nArray row: \nnArray column: ")
 331   (array-move-to-cell
 332    (limit-index a-row array-max-row)
 333    (limit-index a-column array-max-column))
 334   (array-normalize-cursor))
 335
 336 \f
 337
 338 ;;; Internal copying functions.
 339
 340 (defun array-field-string ()
 341   "Return the field string at the current cursor location."
 342   ;; Requires that array-buffer-column be current.
 343   (buffer-substring
 344    (save-excursion (array-beginning-of-field t) (point))
 345    (save-excursion (array-end-of-field t) (point))))
 346
 347 (defun array-copy-once-vertically (sign)
 348   "Copy the current field into one array row in direction SIGN (1 or -1).
 349 Leave point at the beginning of the field and return the new array row.
 350 If requested to move beyond the array bounds, signal an error."
 351   ;; Requires that array-buffer-line, array-buffer-column, and array-copy-string be current.
 352   (let ((a-row (array-move-one-row sign)))
 353     (let ((inhibit-quit t))
 354       (delete-region (point) (save-excursion (array-end-of-field t) (point)))
 355       (insert array-copy-string))
 356     (move-to-column array-buffer-column)
 357     a-row))
 358
 359 (defun array-copy-once-horizontally (sign)
 360   "Copy the current field into one array column in direction SIGN (1 or -1).
 361 Leave point at the beginning of the field and return the new array column.
 362 If requested to move beyond the array bounds, signal an error."
 363   ;; Requires that array-buffer-line, array-buffer-column, and array-copy-string be current.
 364   (let ((a-column (array-move-one-column sign)))
 365     (array-update-buffer-position)
 366     (let ((inhibit-quit t))
 367       (delete-region (point) (save-excursion (array-end-of-field t) (point)))
 368       (insert array-copy-string))
 369     (move-to-column array-buffer-column)
 370     a-column))
 371
 372 (defun array-copy-to-row (a-row)
 373   "Copy the current field vertically into every cell up to and including A-ROW.
 374 Leave point at the beginning of the field."
 375   ;; Requires that array-buffer-line, array-buffer-column, array-row, and
 376   ;;  array-copy-string be current.
 377   (let* ((num (- a-row array-row))
 378          (count (abs num))
 379          (sign (if (zerop count) () (/ num count))))
 380     (while (> count 0)
 381       (array-move-one-row sign)
 382       (array-update-buffer-position)
 383       (let ((inhibit-quit t))
 384         (delete-region (point) (save-excursion (array-end-of-field t) (point)))
 385         (insert array-copy-string))
 386       (move-to-column array-buffer-column)
 387       (setq count (1- count)))))
 388
 389 (defun array-copy-to-column (a-column)
 390   "Copy current field horizontally into every cell up to and including A-COLUMN.
 391 Leave point at the beginning of the field."
 392   ;; Requires that array-buffer-line, array-buffer-column, array-column, and
 393   ;;  array-copy-string be current.
 394   (let* ((num (- a-column array-column))
 395          (count (abs num))
 396          (sign (if (zerop count) () (/ num count))))
 397     (while (> count 0)
 398       (array-move-one-column sign)
 399       (array-update-buffer-position)
 400       (let ((inhibit-quit t))
 401         (delete-region (point) (save-excursion (array-end-of-field t) (point)))
 402         (insert array-copy-string))
 403       (move-to-column array-buffer-column)
 404       (setq count (1- count)))))
 405
 406 (defun array-copy-to-cell (a-row a-column)
 407   "Copy the current field into the cell at A-ROW, A-COLUMN.
 408 Leave point at the beginning of the field."
 409   ;; Requires that array-copy-string be current.
 410   (array-move-to-cell a-row a-column)
 411   (array-update-buffer-position)
 412   (delete-region (point) (save-excursion (array-end-of-field t) (point)))
 413   (insert array-copy-string)
 414   (move-to-column array-buffer-column))
 415
 416 \f
 417
 418 ;;; Commands for copying.
 419
 420 (defun array-copy-down (&optional arg)
 421   "Copy the current field one array row down.
 422 If optional ARG is given, copy down through ARG array rows."
 423   (interactive "p")
 424   (let* ((array-buffer-line (current-line))
 425          (array-buffer-column (current-column))
 426          (array-row (or (array-current-row)
 427                            (error "Cursor is not in a valid array cell")))
 428          (array-copy-string (array-field-string)))
 429     (if (= (abs arg) 1)
 430         (array-copy-once-vertically arg)
 431       (array-copy-to-row
 432        (limit-index (+ array-row arg) array-max-row))))
 433   (array-normalize-cursor))
 434
 435 (defun array-copy-up (&optional arg)
 436   "Copy the current field one array row up.
 437 If optional ARG is given, copy up through ARG array rows."
 438   (interactive "p")
 439   (array-copy-down (- arg)))
 440
 441 (defun array-copy-forward (&optional arg)
 442   "Copy the current field one array column to the right.
 443 If optional ARG is given, copy through ARG array columns to the right."
 444   (interactive "p")
 445   (let* ((array-buffer-line (current-line))
 446          (array-buffer-column (current-column))
 447          (array-column (or (array-current-column)
 448                            (error "Cursor is not in a valid array cell")))
 449          (array-copy-string (array-field-string)))
 450     (if (= (abs arg) 1)
 451         (array-copy-once-horizontally arg)
 452       (array-copy-to-column
 453        (limit-index (+ array-column arg) array-max-column))))
 454   (array-normalize-cursor))
 455
 456 (defun array-copy-backward (&optional arg)
 457   "Copy the current field one array column to the left.
 458 If optional ARG is given, copy through ARG array columns to the left."
 459   (interactive "p")
 460   (array-copy-forward (- arg)))
 461
 462 (defun array-copy-column-forward (&optional arg)
 463   "Copy the entire current column in to the column to the right.
 464 If optional ARG is given, copy through ARG array columns to the right."
 465   (interactive "p")
 466   (array-update-buffer-position)
 467   (array-update-array-position)
 468   (if (not array-column)
 469       (error "Cursor is not in a valid array cell"))
 470   (message "Working...")
 471   (let ((this-row 0))
 472     (while (< this-row array-max-row)
 473       (setq this-row (1+ this-row))
 474       (array-move-to-cell this-row array-column)
 475       (array-update-buffer-position)
 476       (let ((array-copy-string (array-field-string)))
 477         (if (= (abs arg) 1)
 478             (array-copy-once-horizontally arg)
 479           (array-copy-to-column
 480            (limit-index (+ array-column arg) array-max-column))))))
 481   (message "Working...done")
 482   (array-move-to-row array-row)
 483   (array-normalize-cursor))
 484
 485 (defun array-copy-column-backward (&optional arg)
 486   "Copy the entire current column one column to the left.
 487 If optional ARG is given, copy through ARG columns to the left."
 488   (interactive "p")
 489   (array-copy-column-forward (- arg)))
 490
 491 (defun array-copy-row-down (&optional arg)
 492   "Copy the entire current row one row down.
 493 If optional ARG is given, copy through ARG rows down."
 494   (interactive "p")
 495   (array-update-buffer-position)
 496   (array-update-array-position)
 497   (if (not array-row)
 498       (error "Cursor is not in a valid array cell"))
 499   (cond
 500    ((and (= array-row 1) (= arg -1))
 501     (error "Beginning of array"))
 502    ((and (= array-row array-max-row) (= arg 1))
 503     (error "End of array"))
 504    (t
 505     (let* ((array-copy-string
 506             (buffer-substring
 507              (save-excursion (array-move-to-cell array-row 1)
 508                              (point))
 509              (save-excursion (array-move-to-cell array-row array-max-column)
 510                              (forward-line 1)
 511                              (point))))
 512            (this-row array-row)
 513            (goal-row (limit-index (+ this-row arg) array-max-row))
 514            (num (- goal-row this-row))
 515            (count (abs num))
 516            (sign (if (not (zerop count)) (/ num count))))
 517       (while (> count 0)
 518         (setq this-row (+ this-row sign))
 519         (array-move-to-cell this-row 1)
 520         (let ((inhibit-quit t))
 521           (delete-region (point)
 522                          (save-excursion
 523                            (array-move-to-cell this-row array-max-column)
 524                            (forward-line 1)
 525                            (point)))
 526           (insert array-copy-string))
 527         (setq count (1- count)))
 528       (array-move-to-cell goal-row (or array-column 1)))))
 529   (array-normalize-cursor))
 530
 531 (defun array-copy-row-up (&optional arg)
 532   "Copy the entire current array row into the row above.
 533 If optional ARG is given, copy through ARG rows up."
 534   (interactive "p")
 535   (array-copy-row-down (- arg)))
 536
 537 (defun array-fill-rectangle ()
 538   "Copy the field at mark into every cell between mark and point."
 539   (interactive)
 540   ;; Bind arguments.
 541   (array-update-buffer-position)
 542   (let ((p-row (or (array-current-row)
 543                    (error "Cursor is not in a valid array cell")))
 544         (p-column (or (array-current-column)
 545                       (error "Cursor is not in a valid array cell")))
 546         (m-row
 547          (save-excursion
 548            (exchange-point-and-mark)
 549            (array-update-buffer-position)
 550            (or (array-current-row)
 551                (error "Mark is not in a valid array cell"))))
 552         (m-column
 553          (save-excursion
 554            (exchange-point-and-mark)
 555            (array-update-buffer-position)
 556            (or (array-current-column)
 557                (error "Mark is not in a valid array cell")))))
 558     (message "Working...")
 559     (let ((top-row (min m-row p-row))
 560           (bottom-row (max m-row p-row))
 561           (left-column (min m-column p-column))
 562           (right-column (max m-column p-column)))
 563       ;; Do the first row.
 564       (let ((array-copy-string
 565              (save-excursion
 566                (array-move-to-cell m-row m-column)
 567                (array-update-buffer-position)
 568                (array-field-string))))
 569         (array-copy-to-cell top-row left-column)
 570         (array-update-array-position top-row left-column)
 571         (array-update-buffer-position)
 572         (array-copy-to-column right-column))
 573       ;; Do the rest of the rows.
 574       (array-move-to-cell top-row left-column)
 575       (let ((array-copy-string
 576              (buffer-substring
 577               (point)
 578               (save-excursion
 579                 (array-move-to-cell top-row right-column)
 580                 (setq array-buffer-column (current-column))
 581                 (array-end-of-field t)
 582                 (point))))
 583             (this-row top-row))
 584         (while (/= this-row bottom-row)
 585           (setq this-row (1+ this-row))
 586           (array-move-to-cell this-row left-column)
 587           (let ((inhibit-quit t))
 588             (delete-region
 589              (point)
 590              (save-excursion
 591                (array-move-to-cell this-row right-column)
 592                (setq array-buffer-column (current-column))
 593                (array-end-of-field t)
 594                (point)))
 595             (insert array-copy-string)))))
 596     (message "Working...done")
 597     (array-goto-cell p-row p-column)))
 598
 599 \f
 600
 601 ;;; Reconfiguration of the array.
 602
 603 (defun array-make-template ()
 604   "Create the template of an array."
 605   (interactive)
 606   ;; If there is a conflict between array-field-width and init-string, resolve it.
 607   (let ((check t)
 608         (len))
 609     (while check
 610       (setq array-init-field (read-input "Initial field value: "))
 611       (setq len (length array-init-field))
 612       (if (/= len array-field-width)
 613           (if (y-or-n-p (format "Change field width to %d? " len))
 614               (progn (setq array-field-width len)
 615                      (setq check nil)))
 616         (setq check nil))))
 617   (goto-char (point-min))
 618   (message "Working...")
 619   (let ((this-row 1))
 620     ;; Loop through the rows.
 621     (while (<= this-row array-max-row)
 622       (if array-rows-numbered
 623           (insert (format "%d:\n" this-row)))
 624       (let ((this-column 1))
 625         ;; Loop through the columns.
 626         (while (<= this-column array-max-column)
 627           (insert array-init-field)
 628           (if (and (zerop (% this-column array-columns-per-line))
 629                    (/= this-column array-max-column))
 630               (newline))
 631           (setq this-column (1+ this-column))))
 632       (setq this-row (1+ this-row))
 633       (newline)))
 634   (message "Working...done")
 635   (array-goto-cell 1 1))
 636
 637 (defun array-reconfigure-rows (new-columns-per-line new-rows-numbered)
 638   "Reconfigure the state of `array-rows-numbered' and `array-columns-per-line'.
 639 NEW-COLUMNS-PER-LINE is the desired value of `array-columns-per-line' and
 640 NEW-ROWS-NUMBERED (a character, either ?y or ?n) is the desired value
 641 of array-rows-numbered."
 642   (interactive "nColumns per line: \ncRows numbered? (y or n) ")
 643   ;; Check on new-columns-per-line
 644   (let ((check t))
 645     (while check
 646       (if (and (>= new-columns-per-line 1)
 647                (<= new-columns-per-line array-max-column))
 648           (setq check nil)
 649         (setq new-columns-per-line
 650               (string-to-int
 651                (read-input
 652                 (format "Columns per line (1 - %d): " array-max-column)))))))
 653   ;; Check on new-rows-numbered.  It has to be done this way
 654   ;;  because interactive does not have y-or-n-p.
 655   (cond
 656    ((eq new-rows-numbered ?y)
 657     (setq new-rows-numbered t))
 658    ((eq new-rows-numbered ?n)
 659     (setq new-rows-numbered nil))
 660    (t
 661     (setq new-rows-numbered (y-or-n-p "Rows numbered? "))))
 662   (message "Working...")
 663   (array-update-buffer-position)
 664   (let* ((main-buffer (buffer-name (current-buffer)))
 665          (temp-buffer (generate-new-buffer " *Array*"))
 666          (temp-max-row array-max-row)
 667          (temp-max-column array-max-column)
 668          (old-rows-numbered array-rows-numbered)
 669          (old-columns-per-line array-columns-per-line)
 670          (old-lines-per-row array-lines-per-row)
 671          (old-field-width array-field-width)
 672          (old-line-length array-line-length)
 673          (this-row 1))
 674     (array-update-array-position)
 675     ;; Do the cutting in a temporary buffer.
 676     (copy-to-buffer temp-buffer (point-min) (point-max))
 677     (set-buffer temp-buffer)
 678     (goto-char (point-min))
 679     (while (<= this-row temp-max-row)
 680       ;; Deal with row number.
 681       (cond
 682        ((or (and old-rows-numbered new-rows-numbered)
 683             (and (not old-rows-numbered) (not new-rows-numbered)))
 684         ;; Nothing is changed.
 685         ())
 686        ((and old-rows-numbered (not new-rows-numbered))
 687         ;; Delete the row number.
 688         (kill-line 1))
 689        (t
 690         ;; Add the row number.
 691         (insert-string (format "%d:\n" this-row))))
 692       ;; Deal with the array columns in this row.
 693       (cond
 694        ((= old-columns-per-line new-columns-per-line)
 695         ;; Nothing is changed.  Go to the next row.
 696         (forward-line (- old-lines-per-row (if old-rows-numbered 1 0))))
 697        (t
 698         ;; First expand the row.  Then cut it up into new pieces.
 699         (let ((newlines-to-be-removed
 700                (floor (1- temp-max-column) old-columns-per-line))
 701               (newlines-removed 0)
 702               (newlines-to-be-added
 703                (floor (1- temp-max-column) new-columns-per-line))
 704               (newlines-added 0))
 705           (while (< newlines-removed newlines-to-be-removed)
 706             (move-to-column-untabify
 707              (* (1+ newlines-removed) old-line-length))
 708             (kill-line 1)
 709             (setq newlines-removed (1+ newlines-removed)))
 710           (beginning-of-line)
 711           (while (< newlines-added newlines-to-be-added)
 712             (move-to-column-untabify (* old-field-width new-columns-per-line))
 713             (newline)
 714             (setq newlines-added (1+ newlines-added)))
 715           (forward-line 1))))
 716       (setq this-row (1+ this-row)))
 717     (let ((inhibit-quit t))
 718       (set-buffer main-buffer)
 719       (erase-buffer)
 720       (insert-buffer temp-buffer)
 721       ;; Update local variables.
 722       (setq array-columns-per-line new-columns-per-line)
 723       (setq array-rows-numbered new-rows-numbered)
 724       (setq array-line-length (* old-field-width new-columns-per-line))
 725       (setq array-lines-per-row
 726             (+ (floor (1- temp-max-column) new-columns-per-line)
 727                (if new-rows-numbered 2 1)))
 728       (array-goto-cell (or array-row 1) (or array-column 1)))
 729     (kill-buffer temp-buffer))
 730   (message "Working...done"))
 731
 732 (defun array-expand-rows ()
 733   "Expand the rows so each fits on one line and remove row numbers."
 734   (interactive)
 735   (array-reconfigure-rows array-max-column ?n))
 736
 737 \f
 738
 739 ;;; Utilities.
 740
 741 (defun limit-index (index limit)
 742   (cond ((< index 1) 1)
 743         ((> index limit) limit)
 744         (t index)))
 745
 746 (defun xor (pred1 pred2)
 747   "Return the logical exclusive or of predicates PRED1 and PRED2."
 748   (and (or pred1 pred2)
 749        (not (and pred1 pred2))))
 750
 751 (defun current-line ()
 752   "Return the current buffer line at point.  The first line is 0."
 753   (save-excursion
 754     (beginning-of-line)
 755     (count-lines (point-min) (point))))
 756
 757 (defun move-to-column-untabify (column)
 758   "Move to COLUMN on the current line, untabifying if necessary.
 759 Return COLUMN."
 760   (or (and (= column (move-to-column column))
 761            column)
 762       ;; There is a tab in the way.
 763       (if array-respect-tabs
 764           (error "There is a TAB character in the way")
 765         (progn
 766           (untabify-backward)
 767           (move-to-column column)))))
 768
 769 (defun untabify-backward ()
 770   "Untabify the preceding tab."
 771   (save-excursion
 772     (let ((start (point)))
 773       (backward-char 1)
 774       (untabify (point) start))))
 775
 776 \f
 777
 778 ;;; Array mode.
 779
 780 (defvar array-mode-map nil
 781   "Keymap used in array mode.")
 782
 783 (if array-mode-map
 784     ()
 785   (setq array-mode-map (make-keymap))
 786   ;; Bind keys.
 787   (define-key array-mode-map "\M-ad"   'array-display-local-variables)
 788   (define-key array-mode-map "\M-am"   'array-make-template)
 789   (define-key array-mode-map "\M-ae"   'array-expand-rows)
 790   (define-key array-mode-map "\M-ar"   'array-reconfigure-rows)
 791   (define-key array-mode-map "\M-a="   'array-what-position)
 792   (define-key array-mode-map "\M-ag"   'array-goto-cell)
 793   (define-key array-mode-map "\M-af"   'array-fill-rectangle)
 794   (define-key array-mode-map "\C-n"    'array-next-row)
 795   (define-key array-mode-map "\C-p"    'array-previous-row)
 796   (define-key array-mode-map "\C-f"    'array-forward-column)
 797   (define-key array-mode-map "\C-b"    'array-backward-column)
 798   (define-key array-mode-map "\M-n"    'array-copy-down)
 799   (define-key array-mode-map "\M-p"    'array-copy-up)
 800   (define-key array-mode-map "\M-f"    'array-copy-forward)
 801   (define-key array-mode-map "\M-b"    'array-copy-backward)
 802   (define-key array-mode-map "\M-\C-n" 'array-copy-row-down)
 803   (define-key array-mode-map "\M-\C-p" 'array-copy-row-up)
 804   (define-key array-mode-map "\M-\C-f" 'array-copy-column-forward)
 805   (define-key array-mode-map "\M-\C-b" 'array-copy-column-backward))
 806
 807 (put 'array-mode 'mode-class 'special)
 808
 809 ;;;###autoload
 810 (defun array-mode ()
 811   "Major mode for editing arrays.
 812
 813   Array mode is a specialized mode for editing arrays.  An array is
 814 considered to be a two-dimensional set of strings.  The strings are
 815 NOT recognized as integers or real numbers.
 816
 817   The array MUST reside at the top of the buffer.
 818
 819   TABs are not respected, and may be converted into spaces at any time.
 820 Setting the variable 'array-respect-tabs to non-nil will prevent TAB conversion,
 821 but will cause many functions to give errors if they encounter one.
 822
 823   Upon entering array mode, you will be prompted for the values of
 824 several variables.  Others will be calculated based on the values you
 825 supply.  These variables are all local the the buffer.  Other buffer
 826 in array mode may have different values assigned to the variables.
 827 The variables are:
 828
 829 Variables you assign:
 830      array-max-row:          The number of rows in the array.
 831      array-max-column:       The number of columns in the array.
 832      array-columns-per-line: The number of columns in the array per line of buffer.
 833      array-field-width:      The width of each field, in characters.
 834      array-rows-numbered:    A logical variable describing whether to ignore
 835                        row numbers in the buffer.
 836
 837 Variables which are calculated:
 838      array-line-length:      The number of characters in a buffer line.
 839      array-lines-per-row:    The number of buffer lines used to display each row.
 840
 841   The following commands are available (an asterisk indicates it may
 842 take a numeric prefix argument):
 843
 844     *   \\<array-mode-map>\\[array-forward-column]        Move forward one column.
 845     *   \\[array-backward-column]         Move backward one column.
 846     *   \\[array-next-row]        Move down one row.
 847     *   \\[array-previous-row]    Move up one row.
 848
 849     *   \\[array-copy-forward]    Copy the current field into the column to the right.
 850     *   \\[array-copy-backward]   Copy the current field into the column to the left.
 851     *   \\[array-copy-down]       Copy the current field into the row below.
 852     *   \\[array-copy-up]         Copy the current field into the row above.
 853
 854     *   \\[array-copy-column-forward]   Copy the current column into the column to the right.
 855     *   \\[array-copy-column-backward]   Copy the current column into the column to the left.
 856     *   \\[array-copy-row-down]   Copy the current row into the row below.
 857     *   \\[array-copy-row-up]   Copy the current row into the row above.
 858
 859         \\[array-fill-rectangle]   Copy the field at mark into every cell with row and column
 860                   between that of point and mark.
 861
 862         \\[array-what-position]   Display the current array row and column.
 863         \\[array-goto-cell]       Go to a particular array cell.
 864
 865         \\[array-make-template]   Make a template for a new array.
 866         \\[array-reconfigure-rows]        Reconfigure the array.
 867         \\[array-expand-rows]   Expand the array (remove row numbers and
 868                   newlines inside rows)
 869
 870         \\[array-display-local-variables]   Display the current values of local variables.
 871
 872 Entering array mode calls the function `array-mode-hook'."
 873
 874   (interactive)
 875   ;; Number of rows in the array.
 876   (make-local-variable 'array-max-row)
 877   ;; Number of columns in the array.
 878   (make-local-variable 'array-max-column)
 879   ;; Number of array columns per line.
 880   (make-local-variable 'array-columns-per-line)
 881   ;; Width of a field in the array.
 882   (make-local-variable 'array-field-width)
 883   ;; Are rows numbered in the buffer?
 884   (make-local-variable 'array-rows-numbered)
 885   ;; Length of a line in the array.
 886   (make-local-variable 'array-line-length)
 887   ;; Number of lines per array row.
 888   (make-local-variable 'array-lines-per-row)
 889   ;; Current line number of point in the buffer.
 890   (make-local-variable 'array-buffer-line)
 891   ;; Current column number of point in the buffer.
 892   (make-local-variable 'array-buffer-column)
 893   ;; Current array row location of point.
 894   (make-local-variable 'array-row)
 895   ;; Current array column location of point.
 896   (make-local-variable 'array-column)
 897   ;; Current field string being copied.
 898   (make-local-variable 'array-copy-string)
 899   ;; Should TAB conversion be prevented?
 900   (make-local-variable 'array-respect-tabs)
 901   (setq array-respect-tabs nil)
 902   (array-init-local-variables)
 903   (setq major-mode 'array-mode)
 904   (setq mode-name "Array")
 905   (force-mode-line-update)
 906   (make-local-variable 'truncate-lines)
 907   (setq truncate-lines t)
 908   (setq overwrite-mode 'overwrite-mode-textual)
 909   (use-local-map array-mode-map)
 910   (run-hooks 'array-mode-hook))
 911
 912 \f
 913
 914 ;;; Initialization functions.  These are not interactive.
 915
 916 (defun array-init-local-variables ()
 917   "Initialize the variables associated with the array in this buffer."
 918   (array-init-max-row)
 919   (array-init-max-column)
 920   (array-init-columns-per-line)
 921   (array-init-field-width)
 922   (array-init-rows-numbered)
 923   (array-init-line-length)
 924   (array-init-lines-per-row)
 925   (message ""))
 926
 927 (defun array-init-max-row (&optional arg)
 928   "Initialize the value of `array-max-row'."
 929   (setq array-max-row
 930         (or arg (string-to-int (read-input "Number of array rows: ")))))
 931
 932 (defun array-init-max-column (&optional arg)
 933   "Initialize the value of `array-max-column'."
 934   (setq array-max-column
 935         (or arg (string-to-int (read-input "Number of array columns: ")))))
 936
 937 (defun array-init-columns-per-line (&optional arg)
 938   "Initialize the value of `array-columns-per-line'."
 939   (setq array-columns-per-line
 940         (or arg (string-to-int (read-input "Array columns per line: ")))))
 941
 942 (defun array-init-field-width (&optional arg)
 943   "Initialize the value of `array-field-width'."
 944   (setq array-field-width
 945         (or arg (string-to-int (read-input "Field width: ")))))
 946
 947 (defun array-init-rows-numbered (&optional arg)
 948   "Initialize the value of `array-rows-numbered'."
 949   (setq array-rows-numbered
 950         (or arg (y-or-n-p "Rows numbered? "))))
 951
 952 (defun array-init-line-length (&optional arg)
 953   "Initialize the value of `array-line-length'."
 954   (setq array-line-length
 955         (or arg
 956           (* array-field-width array-columns-per-line))))
 957
 958 (defun array-init-lines-per-row (&optional arg)
 959   "Initialize the value of `array-lines-per-row'."
 960   (setq array-lines-per-row
 961         (or arg
 962           (+ (floor (1- array-max-column) array-columns-per-line)
 963              (if array-rows-numbered 2 1)))))
 964
 965 (provide 'array)
 966
 967 ;;; array.el ends here