lisp/array.el

   1 ;;; array.el --- array editing commands for GNU Emacs
   2
   3 ;; Copyright (C) 1987, 2000-2015 Free Software Foundation, Inc.
   4
   5 ;; Author: David M. Brown
   6 ;; Maintainer: emacs-devel@gnu.org
   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 3 of the License, or
  14 ;; (at your option) 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.  If not, see <http://www.gnu.org/licenses/>.
  23
  24 ;;; Commentary:
  25
  26 ;; Commands for editing a buffer interpreted as a rectangular array
  27 ;; or matrix of whitespace-separated strings.  You specify the array
  28 ;; dimensions and some other parameters at startup time.
  29
  30 ;;  Written by dmb%morgoth@harvard.harvard.edu (address is old)
  31 ;;   (David M. Brown at Goldberg-Zoino & Associates, Inc.)
  32 ;;  Thanks to cph@kleph.ai.mit.edu for assistance
  33
  34 ;; To do:
  35 ;;   Smooth initialization process by grokking local variables list
  36 ;;     at end of buffer or parsing buffer using whitespace as delimiters.
  37 ;;   Make 'array-copy-column-right faster.
  38
  39 \f
  40 ;;; Code:
  41
  42 (defvar array-max-column nil "Number of columns in the array.")
  43 (defvar array-columns-per-line nil "Number of array columns per line.")
  44 (defvar array-buffer-column nil "Current column number of point in the buffer.")
  45 (defvar array-line-length nil "Length of a line in the array.")
  46 (defvar array-buffer-line nil "Current line number of point in the buffer.")
  47 (defvar array-lines-per-row nil "Number of lines per array row.")
  48 (defvar array-max-row nil "Number of rows in the array.")
  49 (defvar array-field-width nil "Width of a field in the array.")
  50 (defvar array-row nil "Current array row location of point.")
  51 (defvar array-column nil "Current array column location of point.")
  52 (defvar array-rows-numbered nil "Are rows numbered in the buffer?")
  53 (defvar array-copy-string nil "Current field string being copied.")
  54 (defvar array-respect-tabs nil "Should TAB conversion be prevented?")
  55
  56 ;;; Internal information functions.
  57
  58 (defun array-cursor-in-array-range ()
  59   "Return t if the cursor is in a valid array cell.
  60 Its ok to be on a row number line."
  61   (let ((columns-last-line (% array-max-column array-columns-per-line)))
  62     ;; Requires array-buffer-line and array-buffer-column to be current.
  63     (not (or
  64           ;; The cursor is too far to the right.
  65           (>= array-buffer-column array-line-length)
  66           ;; The cursor is below the last row.
  67           (>= array-buffer-line (* array-lines-per-row array-max-row))
  68           ;; The cursor is on the last line of the row, the line is smaller
  69           ;;  than the others, and the cursor is after the last array column
  70           ;;  on the line.
  71           (and (zerop (% (1+ array-buffer-line) array-lines-per-row))
  72                (not (zerop columns-last-line))
  73                (>= array-buffer-column (* columns-last-line array-field-width)))))))
  74
  75 (defun array-current-row ()
  76   "Return the array row of the field in which the cursor is located."
  77   ;; Requires array-buffer-line and array-buffer-column to be current.
  78   (and (array-cursor-in-array-range)
  79        (1+ (floor array-buffer-line array-lines-per-row))))
  80
  81 (defun array-current-column ()
  82   "Return the array column of the field in which the cursor is located."
  83   ;; Requires array-buffer-line and array-buffer-column to be current.
  84   (and (array-cursor-in-array-range)
  85        ;; It's not okay to be on a row number line.
  86        (not (and array-rows-numbered
  87                  (zerop (% array-buffer-line array-lines-per-row))))
  88        (+
  89         ;; Array columns due to line differences.
  90         (* array-columns-per-line
  91            (if array-rows-numbered
  92                (1- (% array-buffer-line array-lines-per-row))
  93              (% array-buffer-line array-lines-per-row)))
  94         ;; Array columns on the current line.
  95         (1+ (floor array-buffer-column array-field-width)))))
  96
  97 (defun array-update-array-position (&optional a-row a-column)
  98   "Set `array-row' and `array-column' to their current values.
  99 Set them to the optional arguments A-ROW and A-COLUMN if those are supplied."
 100   ;; Requires that array-buffer-line and array-buffer-column be current.
 101   (setq array-row (or a-row (array-current-row))
 102         array-column (or a-column (array-current-column))))
 103
 104 (defun array-update-buffer-position ()
 105   "Set `array-buffer-line' and `array-buffer-column' to their current values."
 106   (setq array-buffer-line (current-line)
 107         array-buffer-column (current-column)))
 108
 109 \f
 110
 111 ;;; Information commands.
 112
 113 (defun array-what-position ()
 114   "Display the row and column in which the cursor is positioned."
 115   (interactive)
 116   (let ((array-buffer-line (current-line))
 117         (array-buffer-column (current-column)))
 118     (message "Array row: %s  Array column: %s"
 119              (prin1-to-string (array-current-row))
 120              (prin1-to-string (array-current-column)))))
 121
 122 (defun array-display-local-variables ()
 123   "Display the current state of the local variables in the minibuffer."
 124   (interactive)
 125   (let ((buf (buffer-name (current-buffer))))
 126     (with-output-to-temp-buffer "*Local Variables*"
 127       (buffer-disable-undo standard-output)
 128       (terpri)
 129       (princ (format " Buffer:             %s\n\n" buf))
 130       (princ (format "  max-row:           %s\n"
 131                      (prin1-to-string array-max-row)))
 132       (princ (format "  max-column:        %s\n"
 133                      (prin1-to-string array-max-column)))
 134       (princ (format "  columns-per-line:  %s\n"
 135                      (prin1-to-string array-columns-per-line)))
 136       (princ (format "  field-width:       %s\n"
 137                      (prin1-to-string array-field-width)))
 138       (princ (format "  rows-numbered:     %s\n"
 139                      (prin1-to-string array-rows-numbered)))
 140       (princ (format "  lines-per-row:     %s\n"
 141                      (prin1-to-string array-lines-per-row)))
 142       (princ (format "  line-length:       %s\n"
 143                      (prin1-to-string array-line-length))))))
 144
 145 \f
 146
 147 ;;; Internal movement functions.
 148
 149 (defun array-beginning-of-field (&optional go-there)
 150    "Return the column of the beginning of the current field.
 151 Optional argument GO-THERE, if non-nil, means go there too."
 152    ;; Requires that array-buffer-column be current.
 153    (let ((goal-column (- array-buffer-column (% array-buffer-column array-field-width))))
 154      (if go-there
 155          (move-to-column-untabify goal-column)
 156        goal-column)))
 157
 158 (defun array-end-of-field (&optional go-there)
 159   "Return the column of the end of the current array field.
 160 If optional argument GO-THERE is non-nil, go there too."
 161   ;; Requires that array-buffer-column be current.
 162   (let ((goal-column (+ (- array-buffer-column (% array-buffer-column array-field-width))
 163                         array-field-width)))
 164     (if go-there
 165         (move-to-column-untabify goal-column)
 166       goal-column)))
 167
 168 (defun array-move-to-cell (a-row a-column)
 169   "Move to array row A-ROW and array column A-COLUMN.
 170 Leave point at the beginning of the field and return the new buffer column."
 171   (let ((goal-line (+ (* array-lines-per-row (1- a-row))
 172                       (if array-rows-numbered 1 0)
 173                       (floor (1- a-column) array-columns-per-line)))
 174         (goal-column (* array-field-width (% (1- a-column) array-columns-per-line))))
 175     (goto-char (point-min))
 176     (forward-line goal-line)
 177     (move-to-column-untabify goal-column)))
 178
 179 (defun array-move-to-row (a-row)
 180   "Move to array row A-ROW preserving the current array column.
 181 Leave point at the beginning of the field and return the new array row."
 182   ;; Requires that array-buffer-line and array-buffer-column be current.
 183   (let ((goal-line (+ (* array-lines-per-row (1- a-row))
 184                       (% array-buffer-line array-lines-per-row)))
 185         (goal-column (- array-buffer-column (% array-buffer-column array-field-width))))
 186     (forward-line (- goal-line array-buffer-line))
 187     (move-to-column-untabify goal-column)
 188     a-row))
 189
 190 (defun array-move-to-column (a-column)
 191   "Move to array column A-COLUMN preserving the current array row.
 192 Leave point at the beginning of the field and return the new array column."
 193   ;; Requires that array-buffer-line and array-buffer-column be current.
 194   (let ((goal-line (+ (- array-buffer-line (% array-buffer-line array-lines-per-row))
 195                       (if array-rows-numbered 1 0)
 196                       (floor (1- a-column) array-columns-per-line)))
 197         (goal-column (* array-field-width (% (1- a-column) array-columns-per-line))))
 198     (forward-line (- goal-line array-buffer-line))
 199     (move-to-column-untabify goal-column)
 200     a-column))
 201
 202 (defun array-move-one-row (sign)
 203   "Move one array row in direction SIGN (1 or -1).
 204 Leave point at the beginning of the field and return the new array row.
 205 If requested to move beyond the array bounds, signal an error."
 206   ;; Requires that array-buffer-line and array-buffer-column be current.
 207   (let ((goal-column (array-beginning-of-field))
 208         (array-row (or (array-current-row)
 209                        (error "Cursor is not in a valid array cell"))))
 210     (cond ((and (= array-row array-max-row) (= sign 1))
 211            (error "End of array"))
 212           ((and (= array-row 1) (= sign -1))
 213            (error "Beginning of array"))
 214           (t
 215            (progn
 216              (forward-line (* sign array-lines-per-row))
 217              (move-to-column-untabify goal-column)
 218              (+ array-row sign))))))
 219
 220 (defun array-move-one-column (sign)
 221   "Move one array column in direction SIGN (1 or -1).
 222 Leave point at the beginning of the field and return the new array column.
 223 If requested to move beyond the array bounds, signal an error."
 224   ;; Requires that array-buffer-line and array-buffer-column be current.
 225   (let ((array-column (or (array-current-column)
 226                       (error "Cursor is not in a valid array cell"))))
 227     (cond ((and (= array-column array-max-column) (= sign 1))
 228            (error "End of array"))
 229           ((and (= array-column 1) (= sign -1))
 230            (error "Beginning of array"))
 231           (t
 232            (cond
 233             ;; Going backward from first column on the line.
 234             ((and (= sign -1) (= 1 (% array-column array-columns-per-line)))
 235              (forward-line -1)
 236              (move-to-column-untabify
 237               (* array-field-width (1- array-columns-per-line))))
 238             ;; Going forward from last column on the line.
 239             ((and (= sign 1) (zerop (% array-column array-columns-per-line)))
 240              (forward-line 1))
 241             ;; Somewhere in the middle of the line.
 242             (t
 243              (move-to-column-untabify (+ (array-beginning-of-field)
 244                                          (* array-field-width sign)))))
 245            (+ array-column sign)))))
 246
 247 (defun array-normalize-cursor ()
 248   "Move the cursor to the first non-whitespace character in the field.
 249 If necessary, scroll horizontally to keep the cursor in view."
 250   ;; Assumes point is at the beginning of the field.
 251   (let ((array-buffer-column (current-column)))
 252     (skip-chars-forward " \t"
 253                         (1- (save-excursion (array-end-of-field t) (point))))
 254     (array-maybe-scroll-horizontally)))
 255
 256 (defun array-maybe-scroll-horizontally ()
 257   "If necessary, scroll horizontally to keep the cursor in view."
 258   ;; This is only called from array-normalize-cursor so
 259   ;;  array-buffer-column will always be current.
 260   (let ((w-hscroll (window-hscroll))
 261         (w-width (window-width)))
 262     (cond
 263      ((and (>= array-buffer-column w-hscroll)
 264            (<= array-buffer-column (+ w-hscroll w-width)))
 265       ;; It's already visible.  Do nothing.
 266       nil)
 267      ((> array-buffer-column (+ w-hscroll w-width))
 268       ;; It's to the right.  Scroll left.
 269       (scroll-left (- (- array-buffer-column w-hscroll)
 270                       (/ w-width 2))))
 271      (t
 272       ;; It's to the left.  Scroll right.
 273       (scroll-right (+ (- w-hscroll array-buffer-column)
 274                        (/ w-width 2)))))))
 275
 276 \f
 277
 278 ;;; Movement commands.
 279
 280 (defun array-next-row (&optional arg)
 281   "Move down one array row, staying in the current array column.
 282 If optional ARG is given, move down ARG array rows."
 283   (interactive "p")
 284   (let ((array-buffer-line (current-line))
 285         (array-buffer-column (current-column)))
 286     (if (= (abs arg) 1)
 287         (array-move-one-row arg)
 288       (array-move-to-row
 289        (limit-index (+ (or (array-current-row)
 290                            (error "Cursor is not in an array cell"))
 291                        arg)
 292                     array-max-row))))
 293   (array-normalize-cursor))
 294
 295 (defun array-previous-row (&optional arg)
 296   "Move up one array row, staying in the current array column.
 297 If optional ARG is given, move up ARG array rows."
 298   (interactive "p")
 299   (array-next-row (- arg)))
 300
 301 (defun array-forward-column (&optional arg)
 302   "Move forward one field, staying in the current array row.
 303 If optional ARG is given, move forward ARG array columns.
 304 If necessary, keep the cursor in the window by scrolling right or left."
 305   (interactive "p")
 306   (let ((array-buffer-line (current-line))
 307         (array-buffer-column (current-column)))
 308     (if (= (abs arg) 1)
 309         (array-move-one-column arg)
 310       (array-move-to-column
 311        (limit-index (+ (or (array-current-column)
 312                            (error "Cursor is not in an array cell"))
 313                        arg)
 314                     array-max-column))))
 315   (array-normalize-cursor))
 316
 317 (defun array-backward-column (&optional arg)
 318   "Move backward one field, staying in the current array row.
 319 If optional ARG is given, move backward ARG array columns.
 320 If necessary, keep the cursor in the window by scrolling right or left."
 321   (interactive "p")
 322   (array-forward-column (- arg)))
 323
 324 (defun array-goto-cell (a-row a-column)
 325   "Go to array row A-ROW and array column A-COLUMN."
 326   (interactive "nArray row: \nnArray column: ")
 327   (array-move-to-cell
 328    (limit-index a-row array-max-row)
 329    (limit-index a-column array-max-column))
 330   (array-normalize-cursor))
 331
 332 \f
 333
 334 ;;; Internal copying functions.
 335
 336 (defun array-field-string ()
 337   "Return the field string at the current cursor location."
 338   ;; Requires that array-buffer-column be current.
 339   (buffer-substring
 340    (save-excursion (array-beginning-of-field t) (point))
 341    (save-excursion (array-end-of-field t) (point))))
 342
 343 (defun array-copy-once-vertically (sign)
 344   "Copy the current field into one array row in direction SIGN (1 or -1).
 345 Leave point at the beginning of the field and return the new array row.
 346 If requested to move beyond the array bounds, signal an error."
 347   ;; Requires that array-buffer-line, array-buffer-column, and array-copy-string be current.
 348   (let ((a-row (array-move-one-row sign)))
 349     (let ((inhibit-quit t))
 350       (delete-region (point) (save-excursion (array-end-of-field t) (point)))
 351       (insert array-copy-string))
 352     (move-to-column array-buffer-column)
 353     a-row))
 354
 355 (defun array-copy-once-horizontally (sign)
 356   "Copy the current field into one array column in direction SIGN (1 or -1).
 357 Leave point at the beginning of the field and return the new array column.
 358 If requested to move beyond the array bounds, signal an error."
 359   ;; Requires that array-buffer-line, array-buffer-column, and array-copy-string be current.
 360   (let ((a-column (array-move-one-column sign)))
 361     (array-update-buffer-position)
 362     (let ((inhibit-quit t))
 363       (delete-region (point) (save-excursion (array-end-of-field t) (point)))
 364       (insert array-copy-string))
 365     (move-to-column array-buffer-column)
 366     a-column))
 367
 368 (defun array-copy-to-row (a-row)
 369   "Copy the current field vertically into every cell up to and including A-ROW.
 370 Leave point at the beginning of the field."
 371   ;; Requires that array-buffer-line, array-buffer-column, array-row, and
 372   ;;  array-copy-string be current.
 373   (let* ((num (- a-row array-row))
 374          (count (abs num))
 375          (sign (if (zerop count) () (/ num count))))
 376     (while (> count 0)
 377       (array-move-one-row sign)
 378       (array-update-buffer-position)
 379       (let ((inhibit-quit t))
 380         (delete-region (point) (save-excursion (array-end-of-field t) (point)))
 381         (insert array-copy-string))
 382       (move-to-column array-buffer-column)
 383       (setq count (1- count)))))
 384
 385 (defun array-copy-to-column (a-column)
 386   "Copy current field horizontally into every cell up to and including A-COLUMN.
 387 Leave point at the beginning of the field."
 388   ;; Requires that array-buffer-line, array-buffer-column, array-column, and
 389   ;;  array-copy-string be current.
 390   (let* ((num (- a-column array-column))
 391          (count (abs num))
 392          (sign (if (zerop count) () (/ num count))))
 393     (while (> count 0)
 394       (array-move-one-column sign)
 395       (array-update-buffer-position)
 396       (let ((inhibit-quit t))
 397         (delete-region (point) (save-excursion (array-end-of-field t) (point)))
 398         (insert array-copy-string))
 399       (move-to-column array-buffer-column)
 400       (setq count (1- count)))))
 401
 402 (defun array-copy-to-cell (a-row a-column)
 403   "Copy the current field into the cell at A-ROW, A-COLUMN.
 404 Leave point at the beginning of the field."
 405   ;; Requires that array-copy-string be current.
 406   (array-move-to-cell a-row a-column)
 407   (array-update-buffer-position)
 408   (delete-region (point) (save-excursion (array-end-of-field t) (point)))
 409   (insert array-copy-string)
 410   (move-to-column array-buffer-column))
 411
 412 \f
 413
 414 ;;; Commands for copying.
 415
 416 (defun array-copy-down (&optional arg)
 417   "Copy the current field one array row down.
 418 If optional ARG is given, copy down through ARG array rows."
 419   (interactive "p")
 420   (let* ((array-buffer-line (current-line))
 421          (array-buffer-column (current-column))
 422          (array-row (or (array-current-row)
 423                            (error "Cursor is not in a valid array cell")))
 424          (array-copy-string (array-field-string)))
 425     (if (= (abs arg) 1)
 426         (array-copy-once-vertically arg)
 427       (array-copy-to-row
 428        (limit-index (+ array-row arg) array-max-row))))
 429   (array-normalize-cursor))
 430
 431 (defun array-copy-up (&optional arg)
 432   "Copy the current field one array row up.
 433 If optional ARG is given, copy up through ARG array rows."
 434   (interactive "p")
 435   (array-copy-down (- arg)))
 436
 437 (defun array-copy-forward (&optional arg)
 438   "Copy the current field one array column to the right.
 439 If optional ARG is given, copy through ARG array columns to the right."
 440   (interactive "p")
 441   (let* ((array-buffer-line (current-line))
 442          (array-buffer-column (current-column))
 443          (array-column (or (array-current-column)
 444                            (error "Cursor is not in a valid array cell")))
 445          (array-copy-string (array-field-string)))
 446     (if (= (abs arg) 1)
 447         (array-copy-once-horizontally arg)
 448       (array-copy-to-column
 449        (limit-index (+ array-column arg) array-max-column))))
 450   (array-normalize-cursor))
 451
 452 (defun array-copy-backward (&optional arg)
 453   "Copy the current field one array column to the left.
 454 If optional ARG is given, copy through ARG array columns to the left."
 455   (interactive "p")
 456   (array-copy-forward (- arg)))
 457
 458 (defun array-copy-column-forward (&optional arg)
 459   "Copy the entire current column in to the column to the right.
 460 If optional ARG is given, copy through ARG array columns to the right."
 461   (interactive "p")
 462   (array-update-buffer-position)
 463   (array-update-array-position)
 464   (if (not array-column)
 465       (error "Cursor is not in a valid array cell"))
 466   (message "Working...")
 467   (let ((this-row 0))
 468     (while (< this-row array-max-row)
 469       (setq this-row (1+ this-row))
 470       (array-move-to-cell this-row array-column)
 471       (array-update-buffer-position)
 472       (let ((array-copy-string (array-field-string)))
 473         (if (= (abs arg) 1)
 474             (array-copy-once-horizontally arg)
 475           (array-copy-to-column
 476            (limit-index (+ array-column arg) array-max-column))))))
 477   (message "Working...done")
 478   (array-move-to-row array-row)
 479   (array-normalize-cursor))
 480
 481 (defun array-copy-column-backward (&optional arg)
 482   "Copy the entire current column one column to the left.
 483 If optional ARG is given, copy through ARG columns to the left."
 484   (interactive "p")
 485   (array-copy-column-forward (- arg)))
 486
 487 (defun array-copy-row-down (&optional arg)
 488   "Copy the entire current row one row down.
 489 If optional ARG is given, copy through ARG rows down."
 490   (interactive "p")
 491   (array-update-buffer-position)
 492   (array-update-array-position)
 493   (if (not array-row)
 494       (error "Cursor is not in a valid array cell"))
 495   (cond
 496    ((and (= array-row 1) (= arg -1))
 497     (error "Beginning of array"))
 498    ((and (= array-row array-max-row) (= arg 1))
 499     (error "End of array"))
 500    (t
 501     (let* ((array-copy-string
 502             (buffer-substring
 503              (save-excursion (array-move-to-cell array-row 1)
 504                              (point))
 505              (save-excursion (array-move-to-cell array-row array-max-column)
 506                              (forward-line 1)
 507                              (point))))
 508            (this-row array-row)
 509            (goal-row (limit-index (+ this-row arg) array-max-row))
 510            (num (- goal-row this-row))
 511            (count (abs num))
 512            (sign (if (not (zerop count)) (/ num count))))
 513       (while (> count 0)
 514         (setq this-row (+ this-row sign))
 515         (array-move-to-cell this-row 1)
 516         (let ((inhibit-quit t))
 517           (delete-region (point)
 518                          (save-excursion
 519                            (array-move-to-cell this-row array-max-column)
 520                            (forward-line 1)
 521                            (point)))
 522           (insert array-copy-string))
 523         (setq count (1- count)))
 524       (array-move-to-cell goal-row (or array-column 1)))))
 525   (array-normalize-cursor))
 526
 527 (defun array-copy-row-up (&optional arg)
 528   "Copy the entire current array row into the row above.
 529 If optional ARG is given, copy through ARG rows up."
 530   (interactive "p")
 531   (array-copy-row-down (- arg)))
 532
 533 (defun array-fill-rectangle ()
 534   "Copy the field at mark into every cell between mark and point."
 535   (interactive)
 536   ;; Bind arguments.
 537   (array-update-buffer-position)
 538   (let ((p-row (or (array-current-row)
 539                    (error "Cursor is not in a valid array cell")))
 540         (p-column (or (array-current-column)
 541                       (error "Cursor is not in a valid array cell")))
 542         (m-row
 543          (save-excursion
 544            (exchange-point-and-mark)
 545            (array-update-buffer-position)
 546            (or (array-current-row)
 547                (error "Mark is not in a valid array cell"))))
 548         (m-column
 549          (save-excursion
 550            (exchange-point-and-mark)
 551            (array-update-buffer-position)
 552            (or (array-current-column)
 553                (error "Mark is not in a valid array cell")))))
 554     (message "Working...")
 555     (let ((top-row (min m-row p-row))
 556           (bottom-row (max m-row p-row))
 557           (left-column (min m-column p-column))
 558           (right-column (max m-column p-column)))
 559       ;; Do the first row.
 560       (let ((array-copy-string
 561              (save-excursion
 562                (array-move-to-cell m-row m-column)
 563                (array-update-buffer-position)
 564                (array-field-string))))
 565         (array-copy-to-cell top-row left-column)
 566         (array-update-array-position top-row left-column)
 567         (array-update-buffer-position)
 568         (array-copy-to-column right-column))
 569       ;; Do the rest of the rows.
 570       (array-move-to-cell top-row left-column)
 571       (let ((array-copy-string
 572              (buffer-substring
 573               (point)
 574               (save-excursion
 575                 (array-move-to-cell top-row right-column)
 576                 (setq array-buffer-column (current-column))
 577                 (array-end-of-field t)
 578                 (point))))
 579             (this-row top-row))
 580         (while (/= this-row bottom-row)
 581           (setq this-row (1+ this-row))
 582           (array-move-to-cell this-row left-column)
 583           (let ((inhibit-quit t))
 584             (delete-region
 585              (point)
 586              (save-excursion
 587                (array-move-to-cell this-row right-column)
 588                (setq array-buffer-column (current-column))
 589                (array-end-of-field t)
 590                (point)))
 591             (insert array-copy-string)))))
 592     (message "Working...done")
 593     (array-goto-cell p-row p-column)))
 594
 595 \f
 596
 597 ;;; Reconfiguration of the array.
 598
 599 (defun array-make-template ()
 600   "Create the template of an array."
 601   (interactive)
 602   ;; If there is a conflict between array-field-width and init-string, resolve it.
 603   (let ((check t)
 604         (len)
 605         init-field)
 606     (while check
 607       (setq init-field (read-string "Initial field value: "))
 608       (setq len (length init-field))
 609       (if (/= len array-field-width)
 610           (if (y-or-n-p (format "Change field width to %d? " len))
 611               (progn (setq array-field-width len)
 612                      (setq check nil)))
 613         (setq check nil)))
 614     (goto-char (point-min))
 615     (message "Working...")
 616     (let ((this-row 1))
 617       ;; Loop through the rows.
 618       (while (<= this-row array-max-row)
 619         (if array-rows-numbered
 620             (insert (format "%d:\n" this-row)))
 621         (let ((this-column 1))
 622           ;; Loop through the columns.
 623           (while (<= this-column array-max-column)
 624             (insert init-field)
 625             (if (and (zerop (% this-column array-columns-per-line))
 626                      (/= this-column array-max-column))
 627                 (newline))
 628             (setq this-column (1+ this-column))))
 629         (setq this-row (1+ this-row))
 630         (newline)))
 631     (message "Working...done"))
 632   (array-goto-cell 1 1))
 633
 634 (defun array-reconfigure-rows (new-columns-per-line new-rows-numbered)
 635   "Reconfigure the state of `array-rows-numbered' and `array-columns-per-line'.
 636 NEW-COLUMNS-PER-LINE is the desired value of `array-columns-per-line' and
 637 NEW-ROWS-NUMBERED (a character, either ?y or ?n) is the desired value
 638 of `array-rows-numbered'."
 639   (interactive "nColumns per line: \ncRows numbered? (y or n) ")
 640   ;; Check on new-columns-per-line
 641   (let ((check t))
 642     (while check
 643       (if (and (>= new-columns-per-line 1)
 644                (<= new-columns-per-line array-max-column))
 645           (setq check nil)
 646         (setq new-columns-per-line
 647               (string-to-number
 648                (read-string
 649                 (format "Columns per line (1 - %d): " array-max-column)))))))
 650   ;; Check on new-rows-numbered.  It has to be done this way
 651   ;;  because interactive does not have y-or-n-p.
 652   (cond
 653    ((eq new-rows-numbered ?y)
 654     (setq new-rows-numbered t))
 655    ((eq new-rows-numbered ?n)
 656     (setq new-rows-numbered nil))
 657    (t
 658     (setq new-rows-numbered (y-or-n-p "Rows numbered? "))))
 659   (message "Working...")
 660   (array-update-buffer-position)
 661   (let* ((main-buffer (buffer-name (current-buffer)))
 662          (temp-buffer (generate-new-buffer " *Array*"))
 663          (temp-max-row array-max-row)
 664          (temp-max-column array-max-column)
 665          (old-rows-numbered array-rows-numbered)
 666          (old-columns-per-line array-columns-per-line)
 667          (old-lines-per-row array-lines-per-row)
 668          (old-field-width array-field-width)
 669          (old-line-length array-line-length)
 670          (this-row 1))
 671     (array-update-array-position)
 672     ;; Do the cutting in a temporary buffer.
 673     (copy-to-buffer temp-buffer (point-min) (point-max))
 674     (set-buffer temp-buffer)
 675     (goto-char (point-min))
 676     (while (<= this-row temp-max-row)
 677       ;; Deal with row number.
 678       (cond
 679        ((or (and old-rows-numbered new-rows-numbered)
 680             (and (not old-rows-numbered) (not new-rows-numbered)))
 681         ;; Nothing is changed.
 682         ())
 683        ((and old-rows-numbered (not new-rows-numbered))
 684         ;; Delete the row number.
 685         (kill-line 1))
 686        (t
 687         ;; Add the row number.
 688         (insert (format "%d:\n" this-row))))
 689       ;; Deal with the array columns in this row.
 690       (cond
 691        ((= old-columns-per-line new-columns-per-line)
 692         ;; Nothing is changed.  Go to the next row.
 693         (forward-line (- old-lines-per-row (if old-rows-numbered 1 0))))
 694        (t
 695         ;; First expand the row.  Then cut it up into new pieces.
 696         (let ((newlines-to-be-removed
 697                (floor (1- temp-max-column) old-columns-per-line))
 698               (newlines-removed 0)
 699               (newlines-to-be-added
 700                (floor (1- temp-max-column) new-columns-per-line))
 701               (newlines-added 0))
 702           (while (< newlines-removed newlines-to-be-removed)
 703             (move-to-column-untabify
 704              (* (1+ newlines-removed) old-line-length))
 705             (kill-line 1)
 706             (setq newlines-removed (1+ newlines-removed)))
 707           (beginning-of-line)
 708           (while (< newlines-added newlines-to-be-added)
 709             (move-to-column-untabify (* old-field-width new-columns-per-line))
 710             (newline)
 711             (setq newlines-added (1+ newlines-added)))
 712           (forward-line 1))))
 713       (setq this-row (1+ this-row)))
 714     (let ((inhibit-quit t))
 715       (set-buffer main-buffer)
 716       (erase-buffer)
 717       (insert-buffer-substring temp-buffer)
 718       ;; Update local variables.
 719       (setq array-columns-per-line new-columns-per-line)
 720       (setq array-rows-numbered new-rows-numbered)
 721       (setq array-line-length (* old-field-width new-columns-per-line))
 722       (setq array-lines-per-row
 723             (+ (floor (1- temp-max-column) new-columns-per-line)
 724                (if new-rows-numbered 2 1)))
 725       (array-goto-cell (or array-row 1) (or array-column 1)))
 726     (kill-buffer temp-buffer))
 727   (message "Working...done"))
 728
 729 (defun array-expand-rows ()
 730   "Expand the rows so each fits on one line and remove row numbers."
 731   (interactive)
 732   (array-reconfigure-rows array-max-column ?n))
 733
 734 \f
 735
 736 ;;; Utilities.
 737
 738 (defun limit-index (index limit)
 739   (cond ((< index 1) 1)
 740         ((> index limit) limit)
 741         (t index)))
 742
 743 (defun xor (pred1 pred2)
 744   "Return the logical exclusive or of predicates PRED1 and PRED2."
 745   (and (or pred1 pred2)
 746        (not (and pred1 pred2))))
 747
 748 (defun current-line ()
 749   "Return the current buffer line at point.  The first line is 0."
 750   (count-lines (point-min) (line-beginning-position)))
 751
 752 (defun move-to-column-untabify (column)
 753   "Move to COLUMN on the current line, untabifying if necessary.
 754 Return COLUMN."
 755   (or (and (= column (move-to-column column))
 756            column)
 757       ;; There is a tab in the way.
 758       (if array-respect-tabs
 759           (error "There is a TAB character in the way")
 760         (progn
 761           (untabify-backward)
 762           (move-to-column column)))))
 763
 764 (defun untabify-backward ()
 765   "Untabify the preceding TAB."
 766   (save-excursion
 767     (let ((start (point)))
 768       (backward-char 1)
 769       (untabify (point) start))))
 770
 771 \f
 772
 773 ;;; Array mode.
 774
 775 (defvar array-mode-map
 776   (let ((map (make-keymap)))
 777     (define-key map "\M-ad"   'array-display-local-variables)
 778     (define-key map "\M-am"   'array-make-template)
 779     (define-key map "\M-ae"   'array-expand-rows)
 780     (define-key map "\M-ar"   'array-reconfigure-rows)
 781     (define-key map "\M-a="   'array-what-position)
 782     (define-key map "\M-ag"   'array-goto-cell)
 783     (define-key map "\M-af"   'array-fill-rectangle)
 784     (define-key map "\C-n"    'array-next-row)
 785     (define-key map "\C-p"    'array-previous-row)
 786     (define-key map "\C-f"    'array-forward-column)
 787     (define-key map "\C-b"    'array-backward-column)
 788     (define-key map "\M-n"    'array-copy-down)
 789     (define-key map "\M-p"    'array-copy-up)
 790     (define-key map "\M-f"    'array-copy-forward)
 791     (define-key map "\M-b"    'array-copy-backward)
 792     (define-key map "\M-\C-n" 'array-copy-row-down)
 793     (define-key map "\M-\C-p" 'array-copy-row-up)
 794     (define-key map "\M-\C-f" 'array-copy-column-forward)
 795     (define-key map "\M-\C-b" 'array-copy-column-backward)
 796     map)
 797   "Keymap used in array mode.")
 798
 799
 800 (put 'array-mode 'mode-class 'special)
 801
 802 ;;;###autoload
 803 (define-derived-mode array-mode fundamental-mode "Array"
 804   "Major mode for editing arrays.
 805
 806   Array mode is a specialized mode for editing arrays.  An array is
 807 considered to be a two-dimensional set of strings.  The strings are
 808 NOT recognized as integers or real numbers.
 809
 810   The array MUST reside at the top of the buffer.
 811
 812   TABs are not respected, and may be converted into spaces at any time.
 813 Setting the variable `array-respect-tabs' to non-nil will prevent TAB conversion,
 814 but will cause many functions to give errors if they encounter one.
 815
 816   Upon entering array mode, you will be prompted for the values of
 817 several variables.  Others will be calculated based on the values you
 818 supply.  These variables are all local to the buffer.  Other buffer
 819 in array mode may have different values assigned to the variables.
 820 The variables are:
 821
 822 Variables you assign:
 823      array-max-row:          The number of rows in the array.
 824      array-max-column:       The number of columns in the array.
 825      array-columns-per-line: The number of columns in the array per line of buffer.
 826      array-field-width:      The width of each field, in characters.
 827      array-rows-numbered:    A logical variable describing whether to ignore
 828                        row numbers in the buffer.
 829
 830 Variables which are calculated:
 831      array-line-length:      The number of characters in a buffer line.
 832      array-lines-per-row:    The number of buffer lines used to display each row.
 833
 834   The following commands are available (an asterisk indicates it may
 835 take a numeric prefix argument):
 836
 837     *   \\<array-mode-map>\\[array-forward-column]        Move forward one column.
 838     *   \\[array-backward-column]         Move backward one column.
 839     *   \\[array-next-row]        Move down one row.
 840     *   \\[array-previous-row]    Move up one row.
 841
 842     *   \\[array-copy-forward]    Copy the current field into the column to the right.
 843     *   \\[array-copy-backward]   Copy the current field into the column to the left.
 844     *   \\[array-copy-down]       Copy the current field into the row below.
 845     *   \\[array-copy-up]         Copy the current field into the row above.
 846
 847     *   \\[array-copy-column-forward]   Copy the current column into the column to the right.
 848     *   \\[array-copy-column-backward]   Copy the current column into the column to the left.
 849     *   \\[array-copy-row-down]   Copy the current row into the row below.
 850     *   \\[array-copy-row-up]   Copy the current row into the row above.
 851
 852         \\[array-fill-rectangle]   Copy the field at mark into every cell with row and column
 853                   between that of point and mark.
 854
 855         \\[array-what-position]   Display the current array row and column.
 856         \\[array-goto-cell]       Go to a particular array cell.
 857
 858         \\[array-make-template]   Make a template for a new array.
 859         \\[array-reconfigure-rows]        Reconfigure the array.
 860         \\[array-expand-rows]   Expand the array (remove row numbers and
 861                   newlines inside rows)
 862
 863         \\[array-display-local-variables]   Display the current values of local variables.
 864
 865 Entering array mode calls the function `array-mode-hook'."
 866   (make-local-variable 'array-buffer-line)
 867   (make-local-variable 'array-buffer-column)
 868   (make-local-variable 'array-row)
 869   (make-local-variable 'array-column)
 870   (make-local-variable 'array-copy-string)
 871   (set (make-local-variable 'array-respect-tabs) nil)
 872   (set (make-local-variable 'array-max-row)
 873        (read-number "Number of array rows: "))
 874   (set (make-local-variable 'array-max-column)
 875        (read-number "Number of array columns: "))
 876   (set (make-local-variable 'array-columns-per-line)
 877        (read-number "Array columns per line: "))
 878   (set (make-local-variable 'array-field-width)
 879        (read-number "Field width: "))
 880   (set (make-local-variable 'array-rows-numbered)
 881        (y-or-n-p "Rows numbered? "))
 882   (set (make-local-variable 'array-line-length)
 883        (* array-field-width array-columns-per-line))
 884   (set (make-local-variable 'array-lines-per-row)
 885        (+ (floor (1- array-max-column) array-columns-per-line)
 886           (if array-rows-numbered 2 1)))
 887   (message "")
 888   (force-mode-line-update)
 889   (set (make-local-variable 'truncate-lines) t)
 890   (setq overwrite-mode 'overwrite-mode-textual))
 891
 892 \f
 893
 894 (provide 'array)
 895
 896 ;;; array.el ends here