| 1 | ;;; follow.el --- Minor mode, Synchronize windows showing the same buffer. |
| 2 | |
| 3 | ;; Copyright (C) 1995, 1996, 1997, 1999 Free Software Foundation, Inc. |
| 4 | |
| 5 | ;; Author: Anders Lindgren <andersl@andersl.com> |
| 6 | ;; Maintainer: Anders Lindgren <andersl@andersl.com> |
| 7 | ;; Created: 1995-05-25 |
| 8 | ;; Keywords: display, window, minor-mode, convenience |
| 9 | ;; Last Changed: 1999-11-17 |
| 10 | |
| 11 | ;; This file is part of GNU Emacs. |
| 12 | |
| 13 | ;; GNU Emacs is free software; you can redistribute it and/or modify |
| 14 | ;; it under the terms of the GNU General Public License as published by |
| 15 | ;; the Free Software Foundation; either version 2, or (at your option) |
| 16 | ;; any later version. |
| 17 | |
| 18 | ;; GNU Emacs is distributed in the hope that it will be useful, |
| 19 | ;; but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 20 | ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 21 | ;; GNU General Public License for more details. |
| 22 | |
| 23 | ;; You should have received a copy of the GNU General Public License |
| 24 | ;; along with GNU Emacs; see the file COPYING. If not, write to the |
| 25 | ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330, |
| 26 | ;; Boston, MA 02111-1307, USA. |
| 27 | |
| 28 | ;;; Commentary: |
| 29 | |
| 30 | ;;{{{ Documentation |
| 31 | |
| 32 | ;; `Follow mode' is a minor mode for Emacs and XEmacs that |
| 33 | ;; combines windows into one tall virtual window. |
| 34 | ;; |
| 35 | ;; The feeling of a "virtual window" has been accomplished by the use |
| 36 | ;; of two major techniques: |
| 37 | ;; |
| 38 | ;; * The windows always displays adjacent sections of the buffer. |
| 39 | ;; This means that whenever one window is moved, all the |
| 40 | ;; others will follow. (Hence the name Follow Mode.) |
| 41 | ;; |
| 42 | ;; * Should the point (cursor) end up outside a window, another |
| 43 | ;; window displaying that point is selected, if possible. This |
| 44 | ;; makes it possible to walk between windows using normal cursor |
| 45 | ;; movement commands. |
| 46 | ;; |
| 47 | ;; Follow mode comes to its prime when a large screen and two |
| 48 | ;; side-by-side window are used. The user can, with the help of Follow |
| 49 | ;; mode, use two full-height windows as though they would have been |
| 50 | ;; one. Imagine yourself editing a large function, or section of text, |
| 51 | ;; and being able to use 144 lines instead of the normal 72... (your |
| 52 | ;; mileage may vary). |
| 53 | |
| 54 | ;; To test this package, make sure `follow' is loaded, or will be |
| 55 | ;; autoloaded when activated (see below). Then do the following: |
| 56 | ;; |
| 57 | ;; * Find your favorite file (preferably a long one). |
| 58 | ;; |
| 59 | ;; * Resize Emacs so that it will be wide enough for two full size |
| 60 | ;; columns. Delete the other windows and split the window with |
| 61 | ;; the commands `C-x 1 C-x 3'. |
| 62 | ;; |
| 63 | ;; * Give the command: |
| 64 | ;; M-x follow-mode <RETURN> |
| 65 | ;; |
| 66 | ;; * Now the display should look something like (assuming the text "71" |
| 67 | ;; is on line 71): |
| 68 | ;; |
| 69 | ;; +----------+----------+ |
| 70 | ;; |1 |73 | |
| 71 | ;; |2 |74 | |
| 72 | ;; |3 |75 | |
| 73 | ;; ... ... |
| 74 | ;; |71 |143 | |
| 75 | ;; |72 |144 | |
| 76 | ;; +----------+----------+ |
| 77 | ;; |
| 78 | ;; As you can see, the right-hand window starts at line 73, the line |
| 79 | ;; immediately below the end of the left-hand window. As long as |
| 80 | ;; `follow-mode' is active, the two windows will follow eachother! |
| 81 | ;; |
| 82 | ;; * Play around and enjoy! Scroll one window and watch the other. |
| 83 | ;; Jump to the beginning or end. Press `Cursor down' at the last |
| 84 | ;; line of the left-hand window. Enter new lines into the |
| 85 | ;; text. Enter long lines spanning several lines, or several |
| 86 | ;; windows. |
| 87 | ;; |
| 88 | ;; * Should you find `Follow' mode annoying, just type |
| 89 | ;; M-x follow-mode <RETURN> |
| 90 | ;; to turn it off. |
| 91 | |
| 92 | |
| 93 | ;; The command `follow-delete-other-windows-and-split' maximises the |
| 94 | ;; visible area of the current buffer. |
| 95 | ;; |
| 96 | ;; I recommend adding it, and `follow-mode', to hotkeys in the global |
| 97 | ;; key map. To do so, add the following lines (replacing `[f7]' and |
| 98 | ;; `[f8]' with your favorite keys) to the init file: |
| 99 | ;; |
| 100 | ;; (global-set-key [f8] 'follow-mode) |
| 101 | ;; (global-set-key [f7] 'follow-delete-other-windows-and-split) |
| 102 | |
| 103 | |
| 104 | ;; There exists two system variables that controls the appearence of |
| 105 | ;; lines that are wider than the window containing them. The default |
| 106 | ;; is to truncate long lines whenever a window isn't as wide as the |
| 107 | ;; frame. |
| 108 | ;; |
| 109 | ;; To make sure lines are never truncated, please place the following |
| 110 | ;; lines in your init file: |
| 111 | ;; |
| 112 | ;; (setq truncate-lines nil) |
| 113 | ;; (setq truncate-partial-width-windows nil) |
| 114 | |
| 115 | |
| 116 | ;; Since the display of XEmacs is pixel-oriented, a line could be |
| 117 | ;; clipped in half at the bottom of the window. |
| 118 | ;; |
| 119 | ;; To make XEmacs avoid clipping (normal) lines, please place the |
| 120 | ;; following line in your init-file: |
| 121 | ;; |
| 122 | ;; (setq pixel-vertical-clip-threshold 30) |
| 123 | |
| 124 | |
| 125 | ;; The correct way to cofigurate Follow mode, or any other mode for |
| 126 | ;; that matter, is to create one (or more) function that does |
| 127 | ;; whatever you would like to do. The function is then added to |
| 128 | ;; a hook. |
| 129 | ;; |
| 130 | ;; When `Follow' mode is activated, functions stored in the hook |
| 131 | ;; `follow-mode-hook' are called. When it is deactivated |
| 132 | ;; `follow-mode-off-hook' is runed. |
| 133 | ;; |
| 134 | ;; The keymap `follow-key-map' contains key bindings activated by |
| 135 | ;; `follow-mode'. |
| 136 | ;; |
| 137 | ;; Example: |
| 138 | ;; (add-hook 'follow-mode-hook 'my-follow-mode-hook) |
| 139 | ;; |
| 140 | ;; (defun my-follow-mode-hook () |
| 141 | ;; (define-key follow-mode-map "\C-ca" 'your-favorite-function) |
| 142 | ;; (define-key follow-mode-map "\C-cb" 'another-function)) |
| 143 | |
| 144 | |
| 145 | ;; Usage: |
| 146 | ;; |
| 147 | ;; To activate issue the command "M-x follow-mode" |
| 148 | ;; and press return. To deactivate, do it again. |
| 149 | ;; |
| 150 | ;; The following is a list of commands useful when follow-mode is active. |
| 151 | ;; |
| 152 | ;; follow-scroll-up C-c . C-v |
| 153 | ;; Scroll text in a Follow Mode window chain up. |
| 154 | ;; |
| 155 | ;; follow-scroll-down C-c . v |
| 156 | ;; Like `follow-scroll-up', but in the other direction. |
| 157 | ;; |
| 158 | ;; follow-delete-other-windows-and-split C-c . 1 |
| 159 | ;; Maximise the visible area of the current buffer, |
| 160 | ;; and enter Follow Mode. This is a very convenient |
| 161 | ;; way to start Follow Mode, hence it is recomended |
| 162 | ;; that this command is added to the global keymap. |
| 163 | ;; |
| 164 | ;; follow-recenter C-c . C-l |
| 165 | ;; Place the point in the center of the middle window, |
| 166 | ;; or a specified number of lines from either top or bottom. |
| 167 | ;; |
| 168 | ;; follow-switch-to-buffer C-c . b |
| 169 | ;; Switch buffer in all windows displaying the current buffer |
| 170 | ;; in this frame. |
| 171 | ;; |
| 172 | ;; follow-switch-to-buffer-all C-c . C-b |
| 173 | ;; Switch buffer in all windows in the active frame. |
| 174 | ;; |
| 175 | ;; follow-switch-to-current-buffer-all |
| 176 | ;; Show the current buffer in all windows on the current |
| 177 | ;; frame and turn on `follow-mode'. |
| 178 | ;; |
| 179 | ;; follow-first-window C-c . < |
| 180 | ;; Select the first window in the frame showing the same buffer. |
| 181 | ;; |
| 182 | ;; follow-last-window C-c . > |
| 183 | ;; Select the last window in the frame showing the same buffer. |
| 184 | ;; |
| 185 | ;; follow-next-window C-c . n |
| 186 | ;; Select the next window in the frame showing the same buffer. |
| 187 | ;; |
| 188 | ;; follow-previous-window C-c . p |
| 189 | ;; Select the previous window showing the same buffer. |
| 190 | |
| 191 | |
| 192 | ;; Well, it seems ok, but what if I really want to look at two different |
| 193 | ;; positions in the text? Here are two simple methods to use: |
| 194 | ;; |
| 195 | ;; 1) Use multiple frames; `follow' mode only affects windows displayed |
| 196 | ;; in the same frame. (My apoligies to you who can't use frames.) |
| 197 | ;; |
| 198 | ;; 2) Bind `follow-mode' to key so you can turn it off whenever |
| 199 | ;; you want to view two locations. Of course, `follow' mode can |
| 200 | ;; be reactivated by hitting the same key again. |
| 201 | ;; |
| 202 | ;; Example from my ~/.emacs: |
| 203 | ;; (global-set-key [f8] 'follow-mode) |
| 204 | |
| 205 | |
| 206 | ;; Implementation: |
| 207 | ;; |
| 208 | ;; In an ideal world, follow mode would have been implemented in the |
| 209 | ;; kernel of the display routines, making sure that the windows (using |
| 210 | ;; follow mode) ALWAYS are aligned. On planet earth, however, we must |
| 211 | ;; accept a solution where we ALMOST ALWAYS can make sure that the |
| 212 | ;; windows are aligned. |
| 213 | ;; |
| 214 | ;; Follow mode does this in three places: |
| 215 | ;; 1) After each user command. |
| 216 | ;; 2) After a process output has been perfomed. |
| 217 | ;; 3) When a scrollbar has been moved. |
| 218 | ;; |
| 219 | ;; This will cover most situations. (Let me know if there are other |
| 220 | ;; situations that should be covered.) |
| 221 | ;; |
| 222 | ;; Note that only the selected window is checked, for the reason of |
| 223 | ;; efficiency and code complexity. (I.e. it is possible to make a |
| 224 | ;; non-selected windows unaligned. It will, however, pop right back |
| 225 | ;; when it is selected.) |
| 226 | |
| 227 | ;;}}} |
| 228 | |
| 229 | ;;; Code: |
| 230 | |
| 231 | ;;{{{ Preliminaries |
| 232 | |
| 233 | ;; Make the compiler shut up! |
| 234 | ;; There are two strategies: |
| 235 | ;; 1) Shut warnings off completely. |
| 236 | ;; 2) Handle each warning separately. |
| 237 | ;; |
| 238 | ;; Since I would like to see real errors, I've selected the latter |
| 239 | ;; method. |
| 240 | ;; |
| 241 | ;; The problem with undefined variables and functions has been solved |
| 242 | ;; by using `set', `symbol-value' and `symbol-function' rather than |
| 243 | ;; `setq' and direct references to variables and functions. |
| 244 | ;; |
| 245 | ;; For example: |
| 246 | ;; (if (boundp 'foo) ... (symbol-value 'foo) ) |
| 247 | ;; (set 'foo ...) <-- XEmacs doesn't fall for this one. |
| 248 | ;; (funcall (symbol-function 'set) 'bar ...) |
| 249 | ;; |
| 250 | ;; Note: When this file is interpreted, `eval-when-compile' is |
| 251 | ;; evaluted. Since it doesn't hurt to evaluate it, but it is a bit |
| 252 | ;; annoying, we test if the byte-compiler has been loaded. This can, |
| 253 | ;; of course, lead to some occasional unintended evaluation... |
| 254 | ;; |
| 255 | ;; Should someone come up with a better solution, please let me |
| 256 | ;; know. |
| 257 | |
| 258 | (eval-when-compile |
| 259 | (if (or (featurep 'bytecomp) |
| 260 | (featurep 'byte-compile)) |
| 261 | (cond ((string-match "XEmacs" emacs-version) |
| 262 | ;; Make XEmacs shut up! I'm using standard Emacs |
| 263 | ;; functions, they are NOT obsolete! |
| 264 | (if (eq (get 'force-mode-line-update 'byte-compile) |
| 265 | 'byte-compile-obsolete) |
| 266 | (put 'force-mode-line-update 'byte-compile 'nil)) |
| 267 | (if (eq (get 'frame-first-window 'byte-compile) |
| 268 | 'byte-compile-obsolete) |
| 269 | (put 'frame-first-window 'byte-compile 'nil)))))) |
| 270 | |
| 271 | ;;}}} |
| 272 | ;;{{{ Variables |
| 273 | |
| 274 | (defgroup follow nil |
| 275 | "Synchronize windows showing the same buffer." |
| 276 | :prefix "follow-" |
| 277 | :group 'windows |
| 278 | :group 'convenience) |
| 279 | |
| 280 | (defvar follow-mode nil |
| 281 | "Variable indicating if Follow mode is active.") |
| 282 | |
| 283 | (defcustom follow-mode-hook nil |
| 284 | "*Hooks to run when follow-mode is turned on." |
| 285 | :type 'hook |
| 286 | :group 'follow) |
| 287 | |
| 288 | (defcustom follow-mode-off-hook nil |
| 289 | "*Hooks to run when follow-mode is turned off." |
| 290 | :type 'hook |
| 291 | :group 'follow) |
| 292 | |
| 293 | (defvar follow-mode-map nil |
| 294 | "*Minor mode keymap for Follow mode.") |
| 295 | |
| 296 | (defcustom follow-mode-line-text " Follow" |
| 297 | "*Text shown in the mode line when Follow mode is active. |
| 298 | Defaults to \" Follow\". Examples of other values |
| 299 | are \" Fw\", or simply \"\"." |
| 300 | :type 'string |
| 301 | :group 'follow) |
| 302 | |
| 303 | (defcustom follow-auto nil |
| 304 | "*Non-nil activates Follow mode whenever a file is loaded." |
| 305 | :type 'boolean |
| 306 | :group 'follow) |
| 307 | |
| 308 | (defcustom follow-mode-prefix "\C-c." |
| 309 | "*Prefix key to use for follow commands in Follow mode. |
| 310 | The value of this variable is checked as part of loading Follow mode. |
| 311 | After that, changing the prefix key requires manipulating keymaps." |
| 312 | :type 'string |
| 313 | :group 'follow) |
| 314 | |
| 315 | (defcustom follow-intercept-processes |
| 316 | (fboundp 'start-process) |
| 317 | "*When non-nil, Follow Mode will monitor process output." |
| 318 | :type 'boolean |
| 319 | :group 'follow) |
| 320 | |
| 321 | (defvar follow-emacs-version-xemacs-p |
| 322 | (string-match "XEmacs" emacs-version) |
| 323 | "Non-nil when running under XEmacs.") |
| 324 | |
| 325 | (defvar follow-avoid-tail-recenter-p |
| 326 | (not follow-emacs-version-xemacs-p) |
| 327 | "*When non-nil, patch emacs so that tail windows won't be recentered. |
| 328 | |
| 329 | A \"tail window\" is a window that displays only the end of |
| 330 | the buffer. Normally it is practical for the user that empty |
| 331 | windows are recentered automatically. However, when using |
| 332 | Follow Mode it breaks the display when the end is displayed |
| 333 | in a window \"above\" the last window. This is for |
| 334 | example the case when displaying a short page in info. |
| 335 | |
| 336 | Must be set before Follow Mode is loaded. |
| 337 | |
| 338 | Please note that it is not possible to fully prevent Emacs from |
| 339 | recentering empty windows. Please report if you find a repeatable |
| 340 | situation in which Emacs recenters empty windows. |
| 341 | |
| 342 | XEmacs, as of 19.12, does not recenter windows, good!") |
| 343 | |
| 344 | (defvar follow-cache-command-list |
| 345 | '(next-line previous-line forward-char backward-char) |
| 346 | "List of commands that don't require recalculation. |
| 347 | |
| 348 | In order to be able to use the cache, a command should not change the |
| 349 | contents of the buffer, nor should it change selected window or current |
| 350 | buffer. |
| 351 | |
| 352 | The commands in this list are checked at load time. |
| 353 | |
| 354 | To mark other commands as suitable for caching, set the symbol |
| 355 | property `follow-mode-use-cache' to non-nil.") |
| 356 | |
| 357 | (defvar follow-debug nil |
| 358 | "*Non-nil when debugging Follow mode.") |
| 359 | |
| 360 | |
| 361 | ;; Internal variables: |
| 362 | |
| 363 | (defvar follow-internal-force-redisplay nil |
| 364 | "True when Follow mode should redisplay the windows.") |
| 365 | |
| 366 | (defvar follow-process-filter-alist '() |
| 367 | "The original filters for processes intercepted by Follow mode.") |
| 368 | |
| 369 | (defvar follow-active-menu nil |
| 370 | "The menu visible when Follow mode is active.") |
| 371 | |
| 372 | (defvar follow-deactive-menu nil |
| 373 | "The menu visible when Follow mode is deactivated.") |
| 374 | |
| 375 | (defvar follow-inside-post-command-hook nil |
| 376 | "Non-nil when inside Follow modes `post-command-hook'. |
| 377 | Used by `follow-window-size-change'.") |
| 378 | |
| 379 | (defvar follow-windows-start-end-cache nil |
| 380 | "Cache used by `follow-window-start-end'.") |
| 381 | |
| 382 | ;;}}} |
| 383 | ;;{{{ Bug report |
| 384 | |
| 385 | (eval-when-compile (require 'reporter)) |
| 386 | |
| 387 | (defun follow-submit-feedback () |
| 388 | "Submit feedback on Follow mode to the author: andersl@andersl.com" |
| 389 | (interactive) |
| 390 | (require 'reporter) |
| 391 | (and (y-or-n-p "Do you really want to submit a report on Follow mode? ") |
| 392 | (reporter-submit-bug-report |
| 393 | "Anders Lindgren <andersl@andersl.com>" |
| 394 | "follow.el" |
| 395 | '(post-command-hook |
| 396 | post-command-idle-hook |
| 397 | pre-command-hook |
| 398 | window-size-change-functions |
| 399 | window-scroll-functions |
| 400 | follow-mode-hook |
| 401 | follow-mode-off-hook |
| 402 | follow-auto |
| 403 | follow-intercept-processes |
| 404 | follow-avoid-tail-recenter-p |
| 405 | follow-process-filter-alist) |
| 406 | nil |
| 407 | nil |
| 408 | (concat |
| 409 | "Hi Anders!\n\n" |
| 410 | "(I have read the section on how to report bugs in the " |
| 411 | "Emacs manual.)\n\n" |
| 412 | "Even though I know you are busy, I thought you might " |
| 413 | "want to know...\n\n")))) |
| 414 | |
| 415 | ;;}}} |
| 416 | ;;{{{ Debug messages |
| 417 | |
| 418 | ;; This inline function must be as small as possible! |
| 419 | ;; Maybe we should define a macro that expands to nil if |
| 420 | ;; the variable is not set. |
| 421 | |
| 422 | (defsubst follow-debug-message (&rest args) |
| 423 | "Like message, but only active when `follow-debug' is non-nil." |
| 424 | (if (and (boundp 'follow-debug) follow-debug) |
| 425 | (apply 'message args))) |
| 426 | |
| 427 | ;;}}} |
| 428 | |
| 429 | ;;{{{ Keymap/Menu |
| 430 | |
| 431 | ;;; Define keys for the follow-mode minor mode map and replace some |
| 432 | ;;; functions in the global map. All `follow' mode special functions |
| 433 | ;;; can be found on (the somewhat cumbersome) "C-c . <key>" |
| 434 | ;;; (Control-C dot <key>). (As of Emacs 19.29 the keys |
| 435 | ;;; C-c <punctuation character> are reserved for minor modes.) |
| 436 | ;;; |
| 437 | ;;; To change the prefix, redefine `follow-mode-prefix' before |
| 438 | ;;; `follow' is loaded, or see the section on `follow-mode-hook' |
| 439 | ;;; above for an example of how to bind the keys the way you like. |
| 440 | ;;; |
| 441 | ;;; Please note that the keymap is defined the first time this file is |
| 442 | ;;; loaded. Also note that the only legal way to manipulate the |
| 443 | ;;; keymap is to use `define-key'. Don't change it using `setq' or |
| 444 | ;;; similar! |
| 445 | |
| 446 | |
| 447 | (if follow-mode-map |
| 448 | nil |
| 449 | (setq follow-mode-map (make-sparse-keymap)) |
| 450 | (let ((map (make-sparse-keymap))) |
| 451 | (define-key map "\C-v" 'follow-scroll-up) |
| 452 | (define-key map "\M-v" 'follow-scroll-down) |
| 453 | (define-key map "v" 'follow-scroll-down) |
| 454 | (define-key map "1" 'follow-delete-other-windows-and-split) |
| 455 | (define-key map "b" 'follow-switch-to-buffer) |
| 456 | (define-key map "\C-b" 'follow-switch-to-buffer-all) |
| 457 | (define-key map "\C-l" 'follow-recenter) |
| 458 | (define-key map "<" 'follow-first-window) |
| 459 | (define-key map ">" 'follow-last-window) |
| 460 | (define-key map "n" 'follow-next-window) |
| 461 | (define-key map "p" 'follow-previous-window) |
| 462 | |
| 463 | (define-key follow-mode-map follow-mode-prefix map) |
| 464 | |
| 465 | ;; Replace the standard `end-of-buffer', when in Follow Mode. (I |
| 466 | ;; don't see the point in trying to replace every function that |
| 467 | ;; could be enhanced in Follow mode. End-of-buffer is a special |
| 468 | ;; case since it is very simple to define and it greatly enhances |
| 469 | ;; the look and feel of Follow mode.) |
| 470 | ;; |
| 471 | ;; (The function `substitute-key-definition' does not work |
| 472 | ;; in all versions of Emacs.) |
| 473 | (mapcar |
| 474 | (function |
| 475 | (lambda (pair) |
| 476 | (let ((old (car pair)) |
| 477 | (new (cdr pair))) |
| 478 | (mapcar (function (lambda (key) |
| 479 | (define-key follow-mode-map key new))) |
| 480 | (where-is-internal old global-map))))) |
| 481 | '((end-of-buffer . follow-end-of-buffer) |
| 482 | (fkey-end-of-buffer . follow-end-of-buffer))) |
| 483 | |
| 484 | ;;; |
| 485 | ;;; The menu. |
| 486 | ;;; |
| 487 | |
| 488 | (if (not follow-emacs-version-xemacs-p) |
| 489 | |
| 490 | ;; |
| 491 | ;; Emacs |
| 492 | ;; |
| 493 | (let ((menumap (funcall (symbol-function 'make-sparse-keymap) |
| 494 | "Follow")) |
| 495 | (count 0) |
| 496 | id) |
| 497 | (mapcar |
| 498 | (function |
| 499 | (lambda (item) |
| 500 | (setq id |
| 501 | (or (cdr item) |
| 502 | (progn |
| 503 | (setq count (+ count 1)) |
| 504 | (intern (format "separator-%d" count))))) |
| 505 | (define-key menumap (vector id) item) |
| 506 | (or (eq id 'follow-mode) |
| 507 | (put id 'menu-enable 'follow-mode)))) |
| 508 | ;; In reverse order: |
| 509 | '(("Toggle Follow mode" . follow-mode) |
| 510 | ("--") |
| 511 | ("Recenter" . follow-recenter) |
| 512 | ("--") |
| 513 | ("Previous Window" . follow-previous-window) |
| 514 | ("Next Windows" . follow-next-window) |
| 515 | ("Last Window" . follow-last-window) |
| 516 | ("First Window" . follow-first-window) |
| 517 | ("--") |
| 518 | ("Switch To Buffer (all windows)" |
| 519 | . follow-switch-to-buffer-all) |
| 520 | ("Switch To Buffer" . follow-switch-to-buffer) |
| 521 | ("--") |
| 522 | ("Delete Other Windows and Split" |
| 523 | . follow-delete-other-windows-and-split) |
| 524 | ("--") |
| 525 | ("Scroll Down" . follow-scroll-down) |
| 526 | ("Scroll Up" . follow-scroll-up))) |
| 527 | |
| 528 | ;; If there is a `tools' meny, we use it. However, we can't add a |
| 529 | ;; minor-mode specific item to it (it's broken), so we make the |
| 530 | ;; contents ghosted when not in use, and add ourselves to the |
| 531 | ;; global map. If no `tools' menu is present, just make a |
| 532 | ;; top-level menu visible when the mode is activated. |
| 533 | |
| 534 | (let ((tools-map (lookup-key (current-global-map) [menu-bar tools])) |
| 535 | (last nil)) |
| 536 | (if (sequencep tools-map) |
| 537 | (progn |
| 538 | ;; Find the last entry in the menu and store it in `last'. |
| 539 | (mapcar (function |
| 540 | (lambda (x) |
| 541 | (setq last (or (cdr-safe |
| 542 | (cdr-safe |
| 543 | (cdr-safe x))) |
| 544 | last)))) |
| 545 | tools-map) |
| 546 | (if last |
| 547 | (progn |
| 548 | (funcall (symbol-function 'define-key-after) |
| 549 | tools-map [separator-follow] '("--") last) |
| 550 | (funcall (symbol-function 'define-key-after) |
| 551 | tools-map [follow] (cons "Follow" menumap) |
| 552 | 'separator-follow)) |
| 553 | ;; Didn't find the last item, Adding to the top of |
| 554 | ;; tools. (This will probably never happend...) |
| 555 | (define-key (current-global-map) [menu-bar tools follow] |
| 556 | (cons "Follow" menumap)))) |
| 557 | ;; No tools menu, add "Follow" to the menubar. |
| 558 | (define-key follow-mode-map [menu-bar follow] |
| 559 | (cons "Follow" menumap))))) |
| 560 | |
| 561 | ;; |
| 562 | ;; XEmacs. |
| 563 | ;; |
| 564 | |
| 565 | ;; place the menu in the `Tools' menu. |
| 566 | (let ((menu '("Follow" |
| 567 | :filter follow-menu-filter |
| 568 | ["Scroll Up" follow-scroll-up t] |
| 569 | ["Scroll Down" follow-scroll-down t] |
| 570 | ["Delete Other Windows and Split" |
| 571 | follow-delete-other-windows-and-split t] |
| 572 | ["Switch To Buffer" follow-switch-to-buffer t] |
| 573 | ["Switch To Buffer (all windows)" |
| 574 | follow-switch-to-buffer-all t] |
| 575 | ["First Window" follow-first-window t] |
| 576 | ["Last Window" follow-last-window t] |
| 577 | ["Next Windows" follow-next-window t] |
| 578 | ["Previous Window" follow-previous-window t] |
| 579 | ["Recenter" follow-recenter t] |
| 580 | ["Deactivate" follow-mode t]))) |
| 581 | |
| 582 | ;; Why not just `(set-buffer-menubar current-menubar)'? The |
| 583 | ;; question is a very good question. The reason is that under |
| 584 | ;; Emacs, neither `set-buffer-menubar' nor |
| 585 | ;; `current-menubar' is defined, hence the byte-compiler will |
| 586 | ;; warn. |
| 587 | (funcall (symbol-function 'set-buffer-menubar) |
| 588 | (symbol-value 'current-menubar)) |
| 589 | (funcall (symbol-function 'add-submenu) '("Tools") menu)) |
| 590 | |
| 591 | ;; When the mode is not activated, only one item is visible: |
| 592 | ;; "Activate". |
| 593 | (defun follow-menu-filter (menu) |
| 594 | (if follow-mode |
| 595 | menu |
| 596 | '(["Activate " follow-mode t])))))) |
| 597 | |
| 598 | |
| 599 | ;;; Register the follow mode keymap. |
| 600 | (or (assq 'follow-mode minor-mode-map-alist) |
| 601 | (setq minor-mode-map-alist |
| 602 | (cons (cons 'follow-mode follow-mode-map) minor-mode-map-alist))) |
| 603 | |
| 604 | ;;}}} |
| 605 | ;;{{{ Cache |
| 606 | |
| 607 | (let ((cmds follow-cache-command-list)) |
| 608 | (while cmds |
| 609 | (put (car cmds) 'follow-mode-use-cache t) |
| 610 | (setq cmds (cdr cmds)))) |
| 611 | |
| 612 | ;;}}} |
| 613 | |
| 614 | ;;{{{ The mode |
| 615 | |
| 616 | ;;;###autoload |
| 617 | (defun turn-on-follow-mode () |
| 618 | "Turn on Follow mode. Please see the function `follow-mode'." |
| 619 | (interactive) |
| 620 | (follow-mode 1)) |
| 621 | |
| 622 | |
| 623 | ;;;###autoload |
| 624 | (defun turn-off-follow-mode () |
| 625 | "Turn off Follow mode. Please see the function `follow-mode'." |
| 626 | (interactive) |
| 627 | (follow-mode -1)) |
| 628 | |
| 629 | |
| 630 | ;;;###autoload |
| 631 | (defun follow-mode (arg) |
| 632 | "Minor mode that combines windows into one tall virtual window. |
| 633 | |
| 634 | The feeling of a \"virtual window\" has been accomplished by the use |
| 635 | of two major techniques: |
| 636 | |
| 637 | * The windows always displays adjacent sections of the buffer. |
| 638 | This means that whenever one window is moved, all the |
| 639 | others will follow. (Hence the name Follow Mode.) |
| 640 | |
| 641 | * Should the point (cursor) end up outside a window, another |
| 642 | window displaying that point is selected, if possible. This |
| 643 | makes it possible to walk between windows using normal cursor |
| 644 | movement commands. |
| 645 | |
| 646 | Follow mode comes to its prime when used on a large screen and two |
| 647 | side-by-side window are used. The user can, with the help of Follow |
| 648 | mode, use two full-height windows as though they would have been |
| 649 | one. Imagine yourself editing a large function, or section of text, |
| 650 | and being able to use 144 lines instead of the normal 72... (your |
| 651 | mileage may vary). |
| 652 | |
| 653 | To split one large window into two side-by-side windows, the commands |
| 654 | `\\[split-window-horizontally]' or \ |
| 655 | `M-x follow-delete-other-windows-and-split' can be used. |
| 656 | |
| 657 | Only windows displayed in the same frame follow each-other. |
| 658 | |
| 659 | If the variable `follow-intercept-processes' is non-nil, Follow mode |
| 660 | will listen to the output of processes and redisplay accordingly. |
| 661 | \(This is the default.) |
| 662 | |
| 663 | When Follow mode is switched on, the hook `follow-mode-hook' |
| 664 | is called. When turned off, `follow-mode-off-hook' is called. |
| 665 | |
| 666 | Keys specific to Follow mode: |
| 667 | \\{follow-mode-map}" |
| 668 | (interactive "P") |
| 669 | (make-local-variable 'follow-mode) |
| 670 | (put 'follow-mode 'permanent-local t) |
| 671 | (let ((follow-mode-orig follow-mode)) |
| 672 | (setq follow-mode |
| 673 | (if (null arg) |
| 674 | (not follow-mode) |
| 675 | (> (prefix-numeric-value arg) 0))) |
| 676 | (if (and follow-mode follow-intercept-processes) |
| 677 | (follow-intercept-process-output)) |
| 678 | (cond ((and follow-mode (not follow-mode-orig)) ; On |
| 679 | ;; XEmacs: If this is non-nil, the window will scroll before |
| 680 | ;; the point will have a chance to get into the next window. |
| 681 | (if (boundp 'scroll-on-clipped-lines) |
| 682 | (set 'scroll-on-clipped-lines nil)) |
| 683 | (force-mode-line-update) |
| 684 | (add-hook 'post-command-hook 'follow-post-command-hook t) |
| 685 | (if (boundp 'post-command-idle-hook) |
| 686 | (add-hook 'post-command-idle-hook |
| 687 | 'follow-avoid-tail-recenter t)) |
| 688 | (run-hooks 'follow-mode-hook)) |
| 689 | |
| 690 | ((and (not follow-mode) follow-mode-orig) ; Off |
| 691 | (force-mode-line-update) |
| 692 | (run-hooks 'follow-mode-off-hook))))) |
| 693 | |
| 694 | |
| 695 | ;; Register follow-mode as a minor mode. |
| 696 | |
| 697 | (if (fboundp 'add-minor-mode) |
| 698 | ;; XEmacs |
| 699 | (funcall (symbol-function 'add-minor-mode) |
| 700 | 'follow-mode 'follow-mode-line-text) |
| 701 | (or (assq 'follow-mode minor-mode-alist) |
| 702 | (setq minor-mode-alist |
| 703 | (cons '(follow-mode follow-mode-line-text) minor-mode-alist)))) |
| 704 | |
| 705 | ;;}}} |
| 706 | ;;{{{ Find file hook |
| 707 | |
| 708 | ;; This will start follow-mode whenever a new file is loaded, if |
| 709 | ;; the variable `follow-auto' is non-nil. |
| 710 | |
| 711 | (add-hook 'find-file-hooks 'follow-find-file-hook t) |
| 712 | |
| 713 | (defun follow-find-file-hook () |
| 714 | "Find-file hook for Follow Mode. See the variable `follow-auto'." |
| 715 | (if follow-auto (follow-mode t))) |
| 716 | |
| 717 | ;;}}} |
| 718 | |
| 719 | ;;{{{ User functions |
| 720 | |
| 721 | ;;; |
| 722 | ;;; User functions usable when in Follow mode. |
| 723 | ;;; |
| 724 | |
| 725 | ;;{{{ Scroll |
| 726 | |
| 727 | ;; `scroll-up' and `-down', but for windows in Follow Mode. |
| 728 | ;; |
| 729 | ;; Almost like the real thing, excpet when the cursor ends up outside |
| 730 | ;; the top or bottom... In our case however, we end up outside the |
| 731 | ;; window and hence we are recenterd. Should we let `recenter' handle |
| 732 | ;; the point position we would never leave the selected window. To do |
| 733 | ;; it ourselves we would need to do our own redisplay, which is easier |
| 734 | ;; said than done. (Why didn't I do a real display abstraction from |
| 735 | ;; the beginning?) |
| 736 | ;; |
| 737 | ;; We must sometimes set `follow-internal-force-redisplay', otherwise |
| 738 | ;; our post-command-hook will move our windows back into the old |
| 739 | ;; position... (This would also be corrected if we would have had a |
| 740 | ;; good redisplay abstraction.) |
| 741 | |
| 742 | (defun follow-scroll-up (&optional arg) |
| 743 | "Scroll text in a Follow Mode window chain up. |
| 744 | |
| 745 | If called with no ARG, the `next-screen-context-lines' last lines of |
| 746 | the bottom window in the chain will be visible in the top window. |
| 747 | |
| 748 | If called with an argument, scroll ARG lines up. |
| 749 | Negative ARG means scroll downward. |
| 750 | |
| 751 | Works like `scroll-up' when not in Follow Mode." |
| 752 | (interactive "P") |
| 753 | (cond ((not (and (boundp 'follow-mode) follow-mode)) |
| 754 | (scroll-up arg)) |
| 755 | (arg |
| 756 | (save-excursion (scroll-up arg)) |
| 757 | (setq follow-internal-force-redisplay t)) |
| 758 | (t |
| 759 | (let* ((windows (follow-all-followers)) |
| 760 | (end (window-end (car (reverse windows))))) |
| 761 | (if (eq end (point-max)) |
| 762 | (signal 'end-of-buffer nil) |
| 763 | (select-window (car windows)) |
| 764 | ;; `window-end' might return nil. |
| 765 | (if end |
| 766 | (goto-char end)) |
| 767 | (vertical-motion (- next-screen-context-lines)) |
| 768 | (set-window-start (car windows) (point))))))) |
| 769 | |
| 770 | |
| 771 | (defun follow-scroll-down (&optional arg) |
| 772 | "Scroll text in a Follow Mode window chain down. |
| 773 | |
| 774 | If called with no ARG, the `next-screen-context-lines' top lines of |
| 775 | the top window in the chain will be visible in the bottom window. |
| 776 | |
| 777 | If called with an argument, scroll ARG lines down. |
| 778 | Negative ARG means scroll upward. |
| 779 | |
| 780 | Works like `scroll-up' when not in Follow Mode." |
| 781 | (interactive "P") |
| 782 | (cond ((not (and (boundp 'follow-mode) follow-mode)) |
| 783 | (scroll-up arg)) |
| 784 | (arg |
| 785 | (save-excursion (scroll-down arg))) |
| 786 | (t |
| 787 | (let* ((windows (follow-all-followers)) |
| 788 | (win (car (reverse windows))) |
| 789 | (start (window-start (car windows)))) |
| 790 | (if (eq start (point-min)) |
| 791 | (signal 'beginning-of-buffer nil) |
| 792 | (select-window win) |
| 793 | (goto-char start) |
| 794 | (vertical-motion (- (- (window-height win) |
| 795 | 1 |
| 796 | next-screen-context-lines))) |
| 797 | (set-window-start win (point)) |
| 798 | (goto-char start) |
| 799 | (vertical-motion (- next-screen-context-lines 1)) |
| 800 | (setq follow-internal-force-redisplay t)))))) |
| 801 | |
| 802 | ;;}}} |
| 803 | ;;{{{ Buffer |
| 804 | |
| 805 | ;;;###autoload |
| 806 | (defun follow-delete-other-windows-and-split (&optional arg) |
| 807 | "Create two side by side windows and enter Follow Mode. |
| 808 | |
| 809 | Execute this command to display as much as possible of the text |
| 810 | in the selected window. All other windows, in the current |
| 811 | frame, are deleted and the selected window is split in two |
| 812 | side-by-side windows. Follow Mode is activated, hence the |
| 813 | two windows always will display two successive pages. |
| 814 | \(If one window is moved, the other one will follow.) |
| 815 | |
| 816 | If ARG is positive, the leftmost window is selected. If it negative, |
| 817 | the rightmost is selected. If ARG is nil, the leftmost window is |
| 818 | selected if the original window is the first one in the frame. |
| 819 | |
| 820 | To bind this command to a hotkey, place the following line |
| 821 | in your `~/.emacs' file, replacing [f7] by your favourite key: |
| 822 | (global-set-key [f7] 'follow-delete-other-windows-and-split)" |
| 823 | (interactive "P") |
| 824 | (let ((other (or (and (null arg) |
| 825 | (not (eq (selected-window) |
| 826 | (frame-first-window (selected-frame))))) |
| 827 | (and arg |
| 828 | (< (prefix-numeric-value arg) 0)))) |
| 829 | (start (window-start))) |
| 830 | (delete-other-windows) |
| 831 | (split-window-horizontally) |
| 832 | (if other |
| 833 | (progn |
| 834 | (other-window 1) |
| 835 | (set-window-start (selected-window) start) |
| 836 | (setq follow-internal-force-redisplay t))) |
| 837 | (follow-mode 1))) |
| 838 | |
| 839 | (defun follow-switch-to-buffer (buffer) |
| 840 | "Show BUFFER in all windows in the current Follow Mode window chain." |
| 841 | (interactive "BSwitch to Buffer: ") |
| 842 | (let ((orig-window (selected-window)) |
| 843 | (windows (follow-all-followers))) |
| 844 | (while windows |
| 845 | (select-window (car windows)) |
| 846 | (switch-to-buffer buffer) |
| 847 | (setq windows (cdr windows))) |
| 848 | (select-window orig-window))) |
| 849 | |
| 850 | |
| 851 | (defun follow-switch-to-buffer-all (&optional buffer) |
| 852 | "Show BUFFER in all windows on this frame. |
| 853 | Defaults to current buffer." |
| 854 | (interactive (list (read-buffer "Switch to Buffer: " |
| 855 | (current-buffer)))) |
| 856 | (or buffer (setq buffer (current-buffer))) |
| 857 | (let ((orig-window (selected-window))) |
| 858 | (walk-windows |
| 859 | (function |
| 860 | (lambda (win) |
| 861 | (select-window win) |
| 862 | (switch-to-buffer buffer)))) |
| 863 | (select-window orig-window) |
| 864 | (follow-redisplay))) |
| 865 | |
| 866 | |
| 867 | (defun follow-switch-to-current-buffer-all () |
| 868 | "Show current buffer in all windows on this frame, and enter Follow Mode. |
| 869 | |
| 870 | To bind this command to a hotkey place the following line |
| 871 | in your `~/.emacs' file: |
| 872 | (global-set-key [f7] 'follow-switch-to-current-buffer-all)" |
| 873 | (interactive) |
| 874 | (or (and (boundp 'follow-mode) follow-mode) |
| 875 | (follow-mode 1)) |
| 876 | (follow-switch-to-buffer-all)) |
| 877 | |
| 878 | ;;}}} |
| 879 | ;;{{{ Movement |
| 880 | |
| 881 | ;; Note, these functions are not very useful, atleast not unless you |
| 882 | ;; rebind the rather cumbersome key sequence `C-c . p'. |
| 883 | |
| 884 | (defun follow-next-window () |
| 885 | "Select the next window showing the same buffer." |
| 886 | (interactive) |
| 887 | (let ((succ (cdr (follow-split-followers (follow-all-followers))))) |
| 888 | (if succ |
| 889 | (select-window (car succ)) |
| 890 | (error "%s" "No more windows")))) |
| 891 | |
| 892 | |
| 893 | (defun follow-previous-window () |
| 894 | "Select the previous window showing the same buffer." |
| 895 | (interactive) |
| 896 | (let ((pred (car (follow-split-followers (follow-all-followers))))) |
| 897 | (if pred |
| 898 | (select-window (car pred)) |
| 899 | (error "%s" "No more windows")))) |
| 900 | |
| 901 | |
| 902 | (defun follow-first-window () |
| 903 | "Select the first window in the frame showing the same buffer." |
| 904 | (interactive) |
| 905 | (select-window (car (follow-all-followers)))) |
| 906 | |
| 907 | |
| 908 | (defun follow-last-window () |
| 909 | "Select the last window in the frame showing the same buffer." |
| 910 | (interactive) |
| 911 | (select-window (car (reverse (follow-all-followers))))) |
| 912 | |
| 913 | ;;}}} |
| 914 | ;;{{{ Redraw |
| 915 | |
| 916 | (defun follow-recenter (&optional arg) |
| 917 | "Recenter the middle window around point. |
| 918 | Rearrange all other windows around the middle window. |
| 919 | |
| 920 | With a positive argument, place the current line ARG lines |
| 921 | from the top. With a negative, place it -ARG lines from the |
| 922 | bottom." |
| 923 | (interactive "P") |
| 924 | (if arg |
| 925 | (let ((p (point)) |
| 926 | (arg (prefix-numeric-value arg))) |
| 927 | (if (>= arg 0) |
| 928 | ;; Recenter relative to the top. |
| 929 | (progn |
| 930 | (follow-first-window) |
| 931 | (goto-char p) |
| 932 | (recenter arg)) |
| 933 | ;; Recenter relative to the bottom. |
| 934 | (follow-last-window) |
| 935 | (goto-char p) |
| 936 | (recenter arg) |
| 937 | ;; Otherwise, our post-command-hook will move the window |
| 938 | ;; right back. |
| 939 | (setq follow-internal-force-redisplay t))) |
| 940 | ;; Recenter in the middle. |
| 941 | (let* ((dest (point)) |
| 942 | (windows (follow-all-followers)) |
| 943 | (win (nth (/ (- (length windows) 1) 2) windows))) |
| 944 | (select-window win) |
| 945 | (goto-char dest) |
| 946 | (recenter) |
| 947 | ;;(setq follow-internal-force-redisplay t) |
| 948 | ))) |
| 949 | |
| 950 | |
| 951 | (defun follow-redraw () |
| 952 | "Arrange windows displaying the same buffer in successor order. |
| 953 | This function can be called even if the buffer is not in Follow mode. |
| 954 | |
| 955 | Hopefully, there should be no reason to call this function when in |
| 956 | Follow mode since the windows should always be aligned." |
| 957 | (interactive) |
| 958 | (sit-for 0) |
| 959 | (follow-redisplay)) |
| 960 | |
| 961 | ;;}}} |
| 962 | ;;{{{ End of buffer |
| 963 | |
| 964 | (defun follow-end-of-buffer (&optional arg) |
| 965 | "Move point to the end of the buffer, Follow Mode style. |
| 966 | |
| 967 | If the end is not visible, it will be displayed in the last possible |
| 968 | window in the Follow Mode window chain. |
| 969 | |
| 970 | The mark is left at the previous position. With arg N, put point N/10 |
| 971 | of the way from the true end." |
| 972 | (interactive "P") |
| 973 | (let ((followers (follow-all-followers)) |
| 974 | (pos (point))) |
| 975 | (cond (arg |
| 976 | (select-window (car (reverse followers)))) |
| 977 | ((follow-select-if-end-visible |
| 978 | (follow-windows-start-end followers))) |
| 979 | (t |
| 980 | (select-window (car (reverse followers))))) |
| 981 | (goto-char pos) |
| 982 | (end-of-buffer arg))) |
| 983 | |
| 984 | ;;}}} |
| 985 | |
| 986 | ;;}}} |
| 987 | |
| 988 | ;;{{{ Display |
| 989 | |
| 990 | ;;;; The display routines |
| 991 | |
| 992 | ;;{{{ Information gathering functions |
| 993 | |
| 994 | (defun follow-all-followers (&optional testwin) |
| 995 | "Return all windows displaying the same buffer as the TESTWIN. |
| 996 | The list contains only windows displayed in the same frame as TESTWIN. |
| 997 | If TESTWIN is nil the selected window is used." |
| 998 | (or (and testwin (window-live-p testwin)) |
| 999 | (setq testwin (selected-window))) |
| 1000 | (let* ((top (frame-first-window (window-frame testwin))) |
| 1001 | (win top) |
| 1002 | (done nil) |
| 1003 | (windows '()) |
| 1004 | (buffer (window-buffer testwin))) |
| 1005 | (while (and (not done) win) |
| 1006 | (if (eq (window-buffer win) buffer) |
| 1007 | (setq windows (cons win windows))) |
| 1008 | (setq win (next-window win 'not)) |
| 1009 | (if (eq win top) |
| 1010 | (setq done t))) |
| 1011 | (nreverse windows))) |
| 1012 | |
| 1013 | |
| 1014 | (defun follow-split-followers (windows &optional win) |
| 1015 | "Split the WINDOWS into the sets: predecessors and successors. |
| 1016 | Return `(PRED . SUCC)' where `PRED' and `SUCC' are ordered starting |
| 1017 | from the selected window." |
| 1018 | (or win |
| 1019 | (setq win (selected-window))) |
| 1020 | (let ((pred '())) |
| 1021 | (while (not (eq (car windows) win)) |
| 1022 | (setq pred (cons (car windows) pred)) |
| 1023 | (setq windows (cdr windows))) |
| 1024 | (cons pred (cdr windows)))) |
| 1025 | |
| 1026 | |
| 1027 | ;; This function is optimized function for speed! |
| 1028 | |
| 1029 | (defun follow-calc-win-end (&optional win) |
| 1030 | "Calculate the presumed window end for WIN. |
| 1031 | |
| 1032 | Actually, the position returned is the start of the next |
| 1033 | window, normally is the end plus one. |
| 1034 | |
| 1035 | If WIN is nil, the selected window is used. |
| 1036 | |
| 1037 | Returns (end-pos end-of-buffer-p)" |
| 1038 | (if follow-emacs-version-xemacs-p |
| 1039 | ;; XEmacs can calculate the end of the window by using |
| 1040 | ;; the 'guarantee options. GOOD! |
| 1041 | (let ((end (window-end win t))) |
| 1042 | (if (= end (funcall (symbol-function 'point-max) |
| 1043 | (window-buffer win))) |
| 1044 | (list end t) |
| 1045 | (list (+ end 1) nil))) |
| 1046 | ;; Emacs: We have to calculate the end by ourselves. |
| 1047 | ;; This code works on both XEmacs and Emacs, but now |
| 1048 | ;; that XEmacs has got custom-written code, this could |
| 1049 | ;; be optimized for Emacs. |
| 1050 | (let ((orig-win (and win (selected-window))) |
| 1051 | height |
| 1052 | buffer-end-p) |
| 1053 | (if win (select-window win)) |
| 1054 | (prog1 |
| 1055 | (save-excursion |
| 1056 | (goto-char (window-start)) |
| 1057 | (setq height (- (window-height) 1)) |
| 1058 | (setq buffer-end-p |
| 1059 | (if (bolp) |
| 1060 | (not (= height (vertical-motion height))) |
| 1061 | (save-restriction |
| 1062 | ;; Fix a mis-feature in `vertical-motion': |
| 1063 | ;; The start of the window is assumed to |
| 1064 | ;; coinside with the start of a line. |
| 1065 | (narrow-to-region (point) (point-max)) |
| 1066 | (not (= height (vertical-motion height)))))) |
| 1067 | (list (point) buffer-end-p)) |
| 1068 | (if orig-win |
| 1069 | (select-window orig-win)))))) |
| 1070 | |
| 1071 | |
| 1072 | ;; Can't use `save-window-excursion' since it triggers a redraw. |
| 1073 | (defun follow-calc-win-start (windows pos win) |
| 1074 | "Calculate where WIN will start if the first in WINDOWS start at POS. |
| 1075 | |
| 1076 | If WIN is nil the point below all windows is returned." |
| 1077 | (let (start) |
| 1078 | (while (and windows (not (eq (car windows) win))) |
| 1079 | (setq start (window-start (car windows))) |
| 1080 | (set-window-start (car windows) pos 'noforce) |
| 1081 | (setq pos (car (inline (follow-calc-win-end (car windows))))) |
| 1082 | (set-window-start (car windows) start 'noforce) |
| 1083 | (setq windows (cdr windows))) |
| 1084 | pos)) |
| 1085 | |
| 1086 | |
| 1087 | ;; The result from `follow-windows-start-end' is cached when using |
| 1088 | ;; a handful simple commands, like cursor movement commands. |
| 1089 | |
| 1090 | (defsubst follow-cache-valid-p (windows) |
| 1091 | "Test if the cached value of `follow-windows-start-end' can be used. |
| 1092 | Note that this handles the case when the cache has been set to nil." |
| 1093 | (let ((res t) |
| 1094 | (cache follow-windows-start-end-cache)) |
| 1095 | (while (and res windows cache) |
| 1096 | (setq res (and (eq (car windows) |
| 1097 | (car (car cache))) |
| 1098 | (eq (window-start (car windows)) |
| 1099 | (car (cdr (car cache)))))) |
| 1100 | (setq windows (cdr windows)) |
| 1101 | (setq cache (cdr cache))) |
| 1102 | (and res (null windows) (null cache)))) |
| 1103 | |
| 1104 | |
| 1105 | (defsubst follow-invalidate-cache () |
| 1106 | "Force `follow-windows-start-end' to recalculate the end of the window." |
| 1107 | (setq follow-windows-start-end-cache nil)) |
| 1108 | |
| 1109 | |
| 1110 | ;; Build a list of windows and their start and end positions. |
| 1111 | ;; Useful to avoid calculating start/end position whenever they are needed. |
| 1112 | ;; The list has the format: |
| 1113 | ;; ((Win Start End End-of-buffer-visible-p) ...) |
| 1114 | |
| 1115 | ;; Used to have a `save-window-excursion', but it obviously triggered |
| 1116 | ;; redraws of the display. Check if I used it for anything. |
| 1117 | |
| 1118 | |
| 1119 | (defun follow-windows-start-end (windows) |
| 1120 | "Builds a list of (WIN START END BUFFER-END-P) for every window in WINDOWS." |
| 1121 | (if (follow-cache-valid-p windows) |
| 1122 | follow-windows-start-end-cache |
| 1123 | (let ((win-start-end '()) |
| 1124 | (orig-win (selected-window))) |
| 1125 | (while windows |
| 1126 | (select-window (car windows)) |
| 1127 | (setq win-start-end |
| 1128 | (cons (cons (car windows) |
| 1129 | (cons (window-start) |
| 1130 | (follow-calc-win-end))) |
| 1131 | win-start-end)) |
| 1132 | (setq windows (cdr windows))) |
| 1133 | (select-window orig-win) |
| 1134 | (setq follow-windows-start-end-cache (nreverse win-start-end)) |
| 1135 | follow-windows-start-end-cache))) |
| 1136 | |
| 1137 | |
| 1138 | (defsubst follow-pos-visible (pos win win-start-end) |
| 1139 | "Non-nil when POS is visible in WIN." |
| 1140 | (let ((wstart-wend-bend (cdr (assq win win-start-end)))) |
| 1141 | (and (>= pos (car wstart-wend-bend)) |
| 1142 | (or (< pos (car (cdr wstart-wend-bend))) |
| 1143 | (nth 2 wstart-wend-bend))))) |
| 1144 | |
| 1145 | |
| 1146 | ;; By `aligned' we mean that for all adjecent windows, the end of the |
| 1147 | ;; first is equal with the start of the successor. The first window |
| 1148 | ;; should start at a full screen line. |
| 1149 | |
| 1150 | (defsubst follow-windows-aligned-p (win-start-end) |
| 1151 | "Non-nil if the follower WINDOWS are aligned." |
| 1152 | (let ((res t)) |
| 1153 | (save-excursion |
| 1154 | (goto-char (window-start (car (car win-start-end)))) |
| 1155 | (if (bolp) |
| 1156 | nil |
| 1157 | (vertical-motion 0 (car (car win-start-end))) |
| 1158 | (setq res (eq (point) (window-start (car (car win-start-end))))))) |
| 1159 | (while (and res (cdr win-start-end)) |
| 1160 | ;; At least two followers left |
| 1161 | (setq res (eq (car (cdr (cdr (car win-start-end)))) |
| 1162 | (car (cdr (car (cdr win-start-end)))))) |
| 1163 | (setq win-start-end (cdr win-start-end))) |
| 1164 | res)) |
| 1165 | |
| 1166 | |
| 1167 | ;; Check if the point is visible in all windows. (So that |
| 1168 | ;; no one will be recentered.) |
| 1169 | |
| 1170 | (defun follow-point-visible-all-windows-p (win-start-end) |
| 1171 | "Non-nil when the window-point is visible in all windows." |
| 1172 | (let ((res t)) |
| 1173 | (while (and res win-start-end) |
| 1174 | (setq res (follow-pos-visible (window-point (car (car win-start-end))) |
| 1175 | (car (car win-start-end)) |
| 1176 | win-start-end)) |
| 1177 | (setq win-start-end (cdr win-start-end))) |
| 1178 | res)) |
| 1179 | |
| 1180 | |
| 1181 | ;; Make sure WIN always starts at the beginning of an whole screen |
| 1182 | ;; line. If WIN is not aligned the start is updated which probably |
| 1183 | ;; will lead to a redisplay of the screen later on. |
| 1184 | ;; |
| 1185 | ;; This is used with the first window in a follow chain. The reason |
| 1186 | ;; is that we want to detect that the point is outside the window. |
| 1187 | ;; (Without the update, the start of the window will move as the |
| 1188 | ;; user presses BackSpace, and the other window redisplay routines |
| 1189 | ;; will move the start of the window in the wrong direction.) |
| 1190 | |
| 1191 | (defun follow-update-window-start (win) |
| 1192 | "Make sure that the start of WIN starts at a full screen line." |
| 1193 | (save-excursion |
| 1194 | (goto-char (window-start win)) |
| 1195 | (if (bolp) |
| 1196 | nil |
| 1197 | (vertical-motion 0 win) |
| 1198 | (if (eq (point) (window-start win)) |
| 1199 | nil |
| 1200 | (vertical-motion 1 win) |
| 1201 | (set-window-start win (point) 'noforce))))) |
| 1202 | |
| 1203 | ;;}}} |
| 1204 | ;;{{{ Selection functions |
| 1205 | |
| 1206 | ;; Make a window in WINDOWS selected if it currently |
| 1207 | ;; is displaying the position DEST. |
| 1208 | ;; |
| 1209 | ;; We don't select a window if it just has been moved. |
| 1210 | |
| 1211 | (defun follow-select-if-visible (dest win-start-end) |
| 1212 | "Select and return a window, if DEST is visible in it. |
| 1213 | Return the selected window." |
| 1214 | (let ((win nil)) |
| 1215 | (while (and (not win) win-start-end) |
| 1216 | ;; Don't select a window that was just moved. This makes it |
| 1217 | ;; possible to later select the last window after a `end-of-buffer' |
| 1218 | ;; command. |
| 1219 | (if (follow-pos-visible dest (car (car win-start-end)) win-start-end) |
| 1220 | (progn |
| 1221 | (setq win (car (car win-start-end))) |
| 1222 | (select-window win))) |
| 1223 | (setq win-start-end (cdr win-start-end))) |
| 1224 | win)) |
| 1225 | |
| 1226 | |
| 1227 | ;; Lets select a window showing the end. Make sure we only select it if it |
| 1228 | ;; it wasn't just moved here. (i.e. M-> shall not unconditionally place |
| 1229 | ;; the point in the selected window.) |
| 1230 | ;; |
| 1231 | ;; (Compability cludge: in Emacs `window-end' is equal to `point-max'; |
| 1232 | ;; in XEmacs, it is equal to `point-max + 1'. Should I really bother |
| 1233 | ;; checking `window-end' now when I check `end-of-buffer' explicitly?) |
| 1234 | |
| 1235 | (defun follow-select-if-end-visible (win-start-end) |
| 1236 | "Select and return a window, if end is visible in it." |
| 1237 | (let ((win nil)) |
| 1238 | (while (and (not win) win-start-end) |
| 1239 | ;; Don't select a window that was just moved. This makes it |
| 1240 | ;; possible to later select the last window after a `end-of-buffer' |
| 1241 | ;; command. |
| 1242 | (if (and (eq (point-max) (nth 2 (car win-start-end))) |
| 1243 | (nth 3 (car win-start-end)) |
| 1244 | ;; `window-end' might return nil. |
| 1245 | (let ((end (window-end (car (car win-start-end))))) |
| 1246 | (and end |
| 1247 | (eq (point-max) (min (point-max) end))))) |
| 1248 | (progn |
| 1249 | (setq win (car (car win-start-end))) |
| 1250 | (select-window win))) |
| 1251 | (setq win-start-end (cdr win-start-end))) |
| 1252 | win)) |
| 1253 | |
| 1254 | |
| 1255 | ;; Select a window that will display the point if the windows would |
| 1256 | ;; be redisplayed with the first window fixed. This is useful for |
| 1257 | ;; example when the user has pressed return at the bottom of a window |
| 1258 | ;; as the point is not visible in any window. |
| 1259 | |
| 1260 | (defun follow-select-if-visible-from-first (dest windows) |
| 1261 | "Select and return a window with DEST, if WINDOWS are redrawn from top." |
| 1262 | (let ((win nil) |
| 1263 | end-pos-end-p) |
| 1264 | (save-excursion |
| 1265 | (goto-char (window-start (car windows))) |
| 1266 | ;; Make sure the line start in the beginning of a real screen |
| 1267 | ;; line. |
| 1268 | (vertical-motion 0 (car windows)) |
| 1269 | (if (< dest (point)) |
| 1270 | ;; Above the start, not visible. |
| 1271 | nil |
| 1272 | ;; At or below the start. Check the windows. |
| 1273 | (save-window-excursion |
| 1274 | (while (and (not win) windows) |
| 1275 | (set-window-start (car windows) (point) 'noforce) |
| 1276 | (setq end-pos-end-p (follow-calc-win-end (car windows))) |
| 1277 | (goto-char (car end-pos-end-p)) |
| 1278 | ;; Visible, if dest above end, or if eob is visible inside |
| 1279 | ;; the window. |
| 1280 | (if (or (car (cdr end-pos-end-p)) |
| 1281 | (< dest (point))) |
| 1282 | (setq win (car windows)) |
| 1283 | (setq windows (cdr windows))))))) |
| 1284 | (if win |
| 1285 | (select-window win)) |
| 1286 | win)) |
| 1287 | |
| 1288 | |
| 1289 | ;;}}} |
| 1290 | ;;{{{ Redisplay |
| 1291 | |
| 1292 | ;; Redraw all the windows on the screen, starting with the top window. |
| 1293 | ;; The window used as as marker is WIN, or the selcted window if WIN |
| 1294 | ;; is nil. |
| 1295 | |
| 1296 | (defun follow-redisplay (&optional windows win) |
| 1297 | "Reposition the WINDOWS around WIN. |
| 1298 | Should the point be too close to the roof we redisplay everything |
| 1299 | from the top. WINDOWS should contain a list of windows to |
| 1300 | redisplay, it is assumed that WIN is a member of the list. |
| 1301 | Should WINDOWS be nil, the windows displaying the |
| 1302 | same buffer as WIN, in the current frame, are used. |
| 1303 | Should WIN be nil, the selected window is used." |
| 1304 | (or win |
| 1305 | (setq win (selected-window))) |
| 1306 | (or windows |
| 1307 | (setq windows (follow-all-followers win))) |
| 1308 | (follow-downward windows (follow-calculate-first-window-start windows win))) |
| 1309 | |
| 1310 | |
| 1311 | ;; Redisplay a chain of windows. Start every window directly after the |
| 1312 | ;; end of the previous window, to make sure long lines are displayed |
| 1313 | ;; correctly. |
| 1314 | |
| 1315 | (defun follow-downward (windows pos) |
| 1316 | "Redisplay all WINDOWS starting at POS." |
| 1317 | (while windows |
| 1318 | (set-window-start (car windows) pos) |
| 1319 | (setq pos (car (follow-calc-win-end (car windows)))) |
| 1320 | (setq windows (cdr windows)))) |
| 1321 | |
| 1322 | |
| 1323 | ;;(defun follow-downward (windows pos) |
| 1324 | ;; "Redisplay all WINDOWS starting at POS." |
| 1325 | ;; (let (p) |
| 1326 | ;; (while windows |
| 1327 | ;; (setq p (window-point (car windows))) |
| 1328 | ;; (set-window-start (car windows) pos) |
| 1329 | ;; (set-window-point (car windows) (max p pos)) |
| 1330 | ;; (setq pos (car (follow-calc-win-end (car windows)))) |
| 1331 | ;; (setq windows (cdr windows))))) |
| 1332 | |
| 1333 | |
| 1334 | ;; Return the start of the first window. |
| 1335 | ;; |
| 1336 | ;; First, estimate the position. It the value is not perfect (i.e. we |
| 1337 | ;; have somewhere splited a line between windows) we try to enhance |
| 1338 | ;; the value. |
| 1339 | ;; |
| 1340 | ;; The guess is always perfect if no long lines is split between |
| 1341 | ;; windows. |
| 1342 | ;; |
| 1343 | ;; The worst case peformace of probably very bad, but it is very |
| 1344 | ;; unlikely that we ever will miss the correct start by more than one |
| 1345 | ;; or two lines. |
| 1346 | |
| 1347 | (defun follow-calculate-first-window-start (windows &optional win start) |
| 1348 | "Calculate the start of the first window. |
| 1349 | |
| 1350 | WINDOWS is a chain of windows to work with. WIN is the window |
| 1351 | to recenter around. It is assumed that WIN starts at position |
| 1352 | START." |
| 1353 | (or win |
| 1354 | (setq win (selected-window))) |
| 1355 | (or start |
| 1356 | (setq start (window-start win))) |
| 1357 | (let ((guess (follow-estimate-first-window-start windows win start))) |
| 1358 | (if (car guess) |
| 1359 | (cdr guess) |
| 1360 | ;; The guess wasn't exact, try to enhance it. |
| 1361 | (let ((win-start (follow-calc-win-start windows (cdr guess) win))) |
| 1362 | (cond ((= win-start start) |
| 1363 | (follow-debug-message "exact") |
| 1364 | (cdr guess)) |
| 1365 | ((< win-start start) |
| 1366 | (follow-debug-message "above") |
| 1367 | (follow-calculate-first-window-start-from-above |
| 1368 | windows (cdr guess) win start)) |
| 1369 | (t |
| 1370 | (follow-debug-message "below") |
| 1371 | (follow-calculate-first-window-start-from-below |
| 1372 | windows (cdr guess) win start))))))) |
| 1373 | |
| 1374 | |
| 1375 | ;; `exact' is disabled due to XEmacs and fonts of variable |
| 1376 | ;; height. |
| 1377 | (defun follow-estimate-first-window-start (windows win start) |
| 1378 | "Estimate the position of the first window. |
| 1379 | |
| 1380 | Returns (EXACT . POS). If EXACT is non-nil, POS is the starting |
| 1381 | position of the first window. Otherwise it is a good guess." |
| 1382 | (let ((pred (car (follow-split-followers windows win))) |
| 1383 | (exact nil)) |
| 1384 | (save-excursion |
| 1385 | (goto-char start) |
| 1386 | ;(setq exact (bolp)) |
| 1387 | (vertical-motion 0 win) |
| 1388 | (while pred |
| 1389 | (vertical-motion (- 1 (window-height (car pred))) (car pred)) |
| 1390 | (if (not (bolp)) |
| 1391 | (setq exact nil)) |
| 1392 | (setq pred (cdr pred))) |
| 1393 | (cons exact (point))))) |
| 1394 | |
| 1395 | |
| 1396 | ;; Find the starting point, start at GUESS and search downward. |
| 1397 | ;; The returned point is always a point below GUESS. |
| 1398 | |
| 1399 | (defun follow-calculate-first-window-start-from-above |
| 1400 | (windows guess win start) |
| 1401 | (save-excursion |
| 1402 | (let ((done nil) |
| 1403 | win-start |
| 1404 | res) |
| 1405 | (goto-char guess) |
| 1406 | (while (not done) |
| 1407 | (if (not (= (vertical-motion 1 (car windows)) 1)) |
| 1408 | ;; Hit bottom! (Can we really do this?) |
| 1409 | ;; We'll keep it, since it ensures termination. |
| 1410 | (progn |
| 1411 | (setq done t) |
| 1412 | (setq res (point-max))) |
| 1413 | (setq win-start (follow-calc-win-start windows (point) win)) |
| 1414 | (if (>= win-start start) |
| 1415 | (progn |
| 1416 | (setq done t) |
| 1417 | (setq res (point)))))) |
| 1418 | res))) |
| 1419 | |
| 1420 | |
| 1421 | ;; Find the starting point, start at GUESS and search upward. Return |
| 1422 | ;; a point on the same line as GUESS, or above. |
| 1423 | ;; |
| 1424 | ;; (Is this ever used? I must make sure it works just in case it is |
| 1425 | ;; ever called.) |
| 1426 | |
| 1427 | (defun follow-calculate-first-window-start-from-below |
| 1428 | (windows guess &optional win start) |
| 1429 | (setq win (or win (selected-window))) |
| 1430 | (setq start (or start (window-start win))) |
| 1431 | (save-excursion |
| 1432 | (let ((done nil) |
| 1433 | win-start |
| 1434 | res) |
| 1435 | ;; Always calculate what happend when no line is displayed in the first |
| 1436 | ;; window. (The `previous' res is needed below!) |
| 1437 | (goto-char guess) |
| 1438 | (vertical-motion 0 (car windows)) |
| 1439 | (setq res (point)) |
| 1440 | (while (not done) |
| 1441 | (if (not (= (vertical-motion -1 (car windows)) -1)) |
| 1442 | ;; Hit roof! |
| 1443 | (progn |
| 1444 | (setq done t) |
| 1445 | (setq res (point-min))) |
| 1446 | (setq win-start (follow-calc-win-start windows (point) win)) |
| 1447 | (cond ((= win-start start) ; Perfect match, use this value |
| 1448 | (setq done t) |
| 1449 | (setq res (point))) |
| 1450 | ((< win-start start) ; Walked to far, use preious result |
| 1451 | (setq done t)) |
| 1452 | (t ; Store result for next iteration |
| 1453 | (setq res (point)))))) |
| 1454 | res))) |
| 1455 | |
| 1456 | ;;}}} |
| 1457 | ;;{{{ Avoid tail recenter |
| 1458 | |
| 1459 | ;; This sets the window internal flag `force_start'. The effect is that |
| 1460 | ;; windows only displaying the tail isn't recentered. |
| 1461 | ;; Has to be called before every redisplay... (Great isn't it?) |
| 1462 | ;; |
| 1463 | ;; XEmacs doesn't recenter the tail, GOOD! |
| 1464 | ;; |
| 1465 | ;; A window displaying only the tail, is a windows whose |
| 1466 | ;; window-start position is equal to (point-max) of the buffer it |
| 1467 | ;; displays. |
| 1468 | ;; |
| 1469 | ;; This function is also added to `post-command-idle-hook', introduced |
| 1470 | ;; in Emacs 19.30. This is needed since the vaccine injected by the |
| 1471 | ;; call from `post-command-hook' only works until the next redisplay. |
| 1472 | ;; It is possible that the functions in the `post-command-idle-hook' |
| 1473 | ;; can cause a redisplay, and hence a new vaccine is needed. |
| 1474 | ;; |
| 1475 | ;; Sometimes, calling this function could actually cause a redisplay, |
| 1476 | ;; especially if it is placed in the debug filter section. I must |
| 1477 | ;; investigate this further... |
| 1478 | |
| 1479 | (defun follow-avoid-tail-recenter (&rest rest) |
| 1480 | "Make sure windows displaying the end of a buffer aren't recentered. |
| 1481 | |
| 1482 | This is done by reading and rewriting the start positon of |
| 1483 | non-first windows in Follow Mode." |
| 1484 | (if follow-avoid-tail-recenter-p |
| 1485 | (let* ((orig-buffer (current-buffer)) |
| 1486 | (top (frame-first-window (selected-frame))) |
| 1487 | (win top) |
| 1488 | (who '()) ; list of (buffer . frame) |
| 1489 | start |
| 1490 | pair) ; (buffer . frame) |
| 1491 | ;; If the only window in the frame is a minibuffer |
| 1492 | ;; window, `next-window' will never find it again... |
| 1493 | (if (window-minibuffer-p top) |
| 1494 | nil |
| 1495 | (while ;; look, no body! |
| 1496 | (progn |
| 1497 | (setq start (window-start win)) |
| 1498 | (set-buffer (window-buffer win)) |
| 1499 | (setq pair (cons (window-buffer win) (window-frame win))) |
| 1500 | (if (member pair who) |
| 1501 | (if (and (boundp 'follow-mode) follow-mode |
| 1502 | (eq (point-max) start)) |
| 1503 | ;; Write the same window start back, but don't |
| 1504 | ;; set the NOFORCE flag. |
| 1505 | (set-window-start win start)) |
| 1506 | (setq who (cons pair who))) |
| 1507 | (setq win (next-window win 'not t)) |
| 1508 | (not (eq win top)))) ;; Loop while this is true. |
| 1509 | (set-buffer orig-buffer))))) |
| 1510 | |
| 1511 | ;;}}} |
| 1512 | |
| 1513 | ;;}}} |
| 1514 | ;;{{{ Post Command Hook |
| 1515 | |
| 1516 | ;;; The magic little box. This function is called after every command. |
| 1517 | |
| 1518 | ;; This is not as complicated as it seems. It is simply a list of common |
| 1519 | ;; display situations and the actions to take, plus commands for redrawing |
| 1520 | ;; the screen if it should be unaligned. |
| 1521 | ;; |
| 1522 | ;; We divide the check into two parts; whether we are at the end or not. |
| 1523 | ;; This is due to the fact that the end can actaually be visible |
| 1524 | ;; in several window even though they are aligned. |
| 1525 | |
| 1526 | (defun follow-post-command-hook () |
| 1527 | "Ensure that the windows in Follow mode are adjacent after each command." |
| 1528 | (setq follow-inside-post-command-hook t) |
| 1529 | (if (or (not (input-pending-p)) |
| 1530 | ;; Sometimes, in XEmacs, mouse events are not handled |
| 1531 | ;; properly by `input-pending-p'. A typical example is |
| 1532 | ;; when clicking on a node in `info'. |
| 1533 | (and (boundp 'current-mouse-event) |
| 1534 | (symbol-value 'current-mouse-event) |
| 1535 | (fboundp 'button-event-p) |
| 1536 | (funcall (symbol-function 'button-event-p) |
| 1537 | (symbol-value 'current-mouse-event)))) |
| 1538 | ;; Work in the selected window, not in the current buffer. |
| 1539 | (let ((orig-buffer (current-buffer)) |
| 1540 | (win (selected-window))) |
| 1541 | (set-buffer (window-buffer win)) |
| 1542 | (or (and (symbolp this-command) |
| 1543 | (get this-command 'follow-mode-use-cache)) |
| 1544 | (follow-invalidate-cache)) |
| 1545 | (if (and (boundp 'follow-mode) follow-mode |
| 1546 | (not (window-minibuffer-p win))) |
| 1547 | ;; The buffer shown in the selected window is in follow |
| 1548 | ;; mode, lets find the current state of the display and |
| 1549 | ;; cache the result for speed (i.e. `aligned' and `visible'.) |
| 1550 | (let* ((windows (inline (follow-all-followers win))) |
| 1551 | (dest (point)) |
| 1552 | (win-start-end (inline |
| 1553 | (follow-update-window-start (car windows)) |
| 1554 | (follow-windows-start-end windows))) |
| 1555 | (aligned (follow-windows-aligned-p win-start-end)) |
| 1556 | (visible (follow-pos-visible dest win win-start-end))) |
| 1557 | (if (not (and aligned visible)) |
| 1558 | (follow-invalidate-cache)) |
| 1559 | (inline (follow-avoid-tail-recenter)) |
| 1560 | ;; Select a window to display the point. |
| 1561 | (or follow-internal-force-redisplay |
| 1562 | (progn |
| 1563 | (if (eq dest (point-max)) |
| 1564 | ;; We're at the end, we have be be careful since |
| 1565 | ;; the display can be aligned while `dest' can |
| 1566 | ;; be visible in several windows. |
| 1567 | (cond |
| 1568 | ;; Select the current window, but only when |
| 1569 | ;; the display is correct. (When inserting |
| 1570 | ;; character in a tail window, the display is |
| 1571 | ;; not correct, as they are shown twice.) |
| 1572 | ;; |
| 1573 | ;; Never stick to the current window after a |
| 1574 | ;; deletion. The reason is cosmetic, when |
| 1575 | ;; typing `DEL' in a window showing only the |
| 1576 | ;; end of the file, character are removed |
| 1577 | ;; from the window above, which is very |
| 1578 | ;; unintuitive. |
| 1579 | ((and visible |
| 1580 | aligned |
| 1581 | (not (memq this-command |
| 1582 | '(backward-delete-char |
| 1583 | delete-backward-char |
| 1584 | backward-delete-char-untabify |
| 1585 | kill-region)))) |
| 1586 | (follow-debug-message "Max: same")) |
| 1587 | ;; If the end is visible, and the window |
| 1588 | ;; doesn't seems like it just has been moved, |
| 1589 | ;; select it. |
| 1590 | ((follow-select-if-end-visible win-start-end) |
| 1591 | (follow-debug-message "Max: end visible") |
| 1592 | (setq visible t) |
| 1593 | (setq aligned nil) |
| 1594 | (goto-char dest)) |
| 1595 | ;; Just show the end... |
| 1596 | (t |
| 1597 | (follow-debug-message "Max: default") |
| 1598 | (select-window (car (reverse windows))) |
| 1599 | (goto-char dest) |
| 1600 | (setq visible nil) |
| 1601 | (setq aligned nil))) |
| 1602 | |
| 1603 | ;; We're not at the end, here life is much simpler. |
| 1604 | (cond |
| 1605 | ;; This is the normal case! |
| 1606 | ;; It should be optimized for speed. |
| 1607 | ((and visible aligned) |
| 1608 | (follow-debug-message "same")) |
| 1609 | ;; Pick a position in any window. If the |
| 1610 | ;; display is ok, this will pick the `correct' |
| 1611 | ;; window. If the display is wierd do this |
| 1612 | ;; anyway, this will be the case after a delete |
| 1613 | ;; at the beginning of the window. |
| 1614 | ((follow-select-if-visible dest win-start-end) |
| 1615 | (follow-debug-message "visible") |
| 1616 | (setq visible t) |
| 1617 | (goto-char dest)) |
| 1618 | ;; Not visible anywhere else, lets pick this one. |
| 1619 | ;; (Is this case used?) |
| 1620 | (visible |
| 1621 | (follow-debug-message "visible in selected.")) |
| 1622 | ;; Far out! |
| 1623 | ((eq dest (point-min)) |
| 1624 | (follow-debug-message "min") |
| 1625 | (select-window (car windows)) |
| 1626 | (goto-char dest) |
| 1627 | (set-window-start (selected-window) (point-min)) |
| 1628 | (setq win-start-end (follow-windows-start-end windows)) |
| 1629 | (follow-invalidate-cache) |
| 1630 | (setq visible t) |
| 1631 | (setq aligned nil)) |
| 1632 | ;; If we can position the cursor without moving the first |
| 1633 | ;; window, do it. This is the case that catches `RET' |
| 1634 | ;; at the bottom of a window. |
| 1635 | ((follow-select-if-visible-from-first dest windows) |
| 1636 | (follow-debug-message "Below first") |
| 1637 | (setq visible t) |
| 1638 | (setq aligned t) |
| 1639 | (follow-redisplay windows (car windows)) |
| 1640 | (goto-char dest)) |
| 1641 | ;; None of the above. For simplicity, we stick to the |
| 1642 | ;; selected window. |
| 1643 | (t |
| 1644 | (follow-debug-message "None") |
| 1645 | (setq visible nil) |
| 1646 | (setq aligned nil)))) |
| 1647 | ;; If a new window has been selected, make sure that the |
| 1648 | ;; old is not scrolled when the point is outside the |
| 1649 | ;; window. |
| 1650 | (or (eq win (selected-window)) |
| 1651 | (let ((p (window-point win))) |
| 1652 | (set-window-start win (window-start win) nil) |
| 1653 | (set-window-point win p))))) |
| 1654 | ;; Make sure the point is visible in the selected window. |
| 1655 | ;; (This could lead to a scroll.) |
| 1656 | (if (or visible |
| 1657 | (follow-pos-visible dest win win-start-end)) |
| 1658 | nil |
| 1659 | (sit-for 0) |
| 1660 | (follow-avoid-tail-recenter) |
| 1661 | (setq win-start-end (follow-windows-start-end windows)) |
| 1662 | (follow-invalidate-cache) |
| 1663 | (setq aligned nil)) |
| 1664 | ;; Redraw the windows whenever needed. |
| 1665 | (if (or follow-internal-force-redisplay |
| 1666 | (not (or aligned |
| 1667 | (follow-windows-aligned-p win-start-end))) |
| 1668 | (not (inline (follow-point-visible-all-windows-p |
| 1669 | win-start-end)))) |
| 1670 | (progn |
| 1671 | (setq follow-internal-force-redisplay nil) |
| 1672 | (follow-redisplay windows (selected-window)) |
| 1673 | (setq win-start-end (follow-windows-start-end windows)) |
| 1674 | (follow-invalidate-cache) |
| 1675 | ;; When the point ends up in another window. This |
| 1676 | ;; happends when dest is in the beginning of the |
| 1677 | ;; file and the selected window is not the first. |
| 1678 | ;; It can also, in rare situations happend when |
| 1679 | ;; long lines are used and there is a big |
| 1680 | ;; difference between the width of the windows. |
| 1681 | ;; (When scrolling one line in a wide window which |
| 1682 | ;; will cause a move larger that an entire small |
| 1683 | ;; window.) |
| 1684 | (if (follow-pos-visible dest win win-start-end) |
| 1685 | nil |
| 1686 | (follow-select-if-visible dest win-start-end) |
| 1687 | (goto-char dest)))) |
| 1688 | |
| 1689 | ;; If the region is visible, make it look good when spanning |
| 1690 | ;; multiple windows. |
| 1691 | (if (or (and (boundp 'mark-active) (symbol-value 'mark-active)) |
| 1692 | (and (fboundp 'region-active-p) |
| 1693 | (funcall (symbol-function 'region-active-p)))) |
| 1694 | (follow-maximize-region |
| 1695 | (selected-window) windows win-start-end)) |
| 1696 | |
| 1697 | (inline (follow-avoid-tail-recenter)) |
| 1698 | ;; DEBUG |
| 1699 | ;;(if (not (follow-windows-aligned-p |
| 1700 | ;; (follow-windows-start-end windows))) |
| 1701 | ;; (message "follow-mode: windows still unaligend!")) |
| 1702 | ;; END OF DEBUG |
| 1703 | ) ; Matches (let* |
| 1704 | ;; Buffer not in follow mode: |
| 1705 | ;; We still must update the windows displaying the tail so that |
| 1706 | ;; Emacs won't recenter them. |
| 1707 | (follow-avoid-tail-recenter)) |
| 1708 | (set-buffer orig-buffer))) |
| 1709 | (setq follow-inside-post-command-hook nil)) |
| 1710 | |
| 1711 | ;;}}} |
| 1712 | ;;{{{ The region |
| 1713 | |
| 1714 | ;; Tries to make the highlighted area representing the region look |
| 1715 | ;; good when spanning several windows. |
| 1716 | ;; |
| 1717 | ;; Not perfect, as the point can't be placed at window end, only at |
| 1718 | ;; end-1. This will highlight a little bit in windows above |
| 1719 | ;; the current. |
| 1720 | |
| 1721 | (defun follow-maximize-region (win windows win-start-end) |
| 1722 | "Make a highlighted region stretching multiple windows look good." |
| 1723 | (let* ((all (follow-split-followers windows win)) |
| 1724 | (pred (car all)) |
| 1725 | (succ (cdr all)) |
| 1726 | data) |
| 1727 | (while pred |
| 1728 | (setq data (assq (car pred) win-start-end)) |
| 1729 | (set-window-point (car pred) (max (nth 1 data) (- (nth 2 data) 1))) |
| 1730 | (setq pred (cdr pred))) |
| 1731 | (while succ |
| 1732 | (set-window-point (car succ) (nth 1 (assq (car succ) win-start-end))) |
| 1733 | (setq succ (cdr succ))))) |
| 1734 | |
| 1735 | ;;}}} |
| 1736 | ;;{{{ Scroll bar |
| 1737 | |
| 1738 | ;;;; Scroll-bar support code. |
| 1739 | |
| 1740 | ;;; Why is it needed? Well, if the selected window is in follow mode, |
| 1741 | ;;; all its follower stick to it blindly. If one of them is scrolled, |
| 1742 | ;;; it immediately returns to the original position when the mouse is |
| 1743 | ;;; released. If the selected window is not a follower of the dragged |
| 1744 | ;;; window the windows will be unaligned. |
| 1745 | |
| 1746 | ;;; The advices doesn't get compiled. Aestetically, this might be a |
| 1747 | ;;; problem but in practical life it isn't. |
| 1748 | |
| 1749 | ;;; Discussion: Now when the other windows in the chain follow the |
| 1750 | ;;; dragged, should we really select it? |
| 1751 | |
| 1752 | (cond ((fboundp 'scroll-bar-drag) |
| 1753 | ;;; |
| 1754 | ;;; Emacs style scrollbars. |
| 1755 | ;;; |
| 1756 | |
| 1757 | ;; Select the dragged window if it is a follower of the |
| 1758 | ;; selected window. |
| 1759 | ;; |
| 1760 | ;; Generate advices of the form: |
| 1761 | ;; (defadvice scroll-bar-drag (after follow-scroll-bar-drag activate) |
| 1762 | ;; "Adviced by `follow-mode'." |
| 1763 | ;; (follow-redraw-after-event (ad-get-arg 0))) |
| 1764 | (let ((cmds '(scroll-bar-drag |
| 1765 | scroll-bar-drag-1 ; Executed at every move. |
| 1766 | scroll-bar-scroll-down |
| 1767 | scroll-bar-scroll-up |
| 1768 | scroll-bar-set-window-start))) |
| 1769 | (while cmds |
| 1770 | (eval |
| 1771 | `(defadvice ,(intern (symbol-name (car cmds))) |
| 1772 | (after |
| 1773 | ,(intern (concat "follow-" (symbol-name (car cmds)))) |
| 1774 | activate) |
| 1775 | "Adviced by Follow Mode." |
| 1776 | (follow-redraw-after-event (ad-get-arg 0)))) |
| 1777 | (setq cmds (cdr cmds)))) |
| 1778 | |
| 1779 | |
| 1780 | (defun follow-redraw-after-event (event) |
| 1781 | "Adviced by Follow mode." |
| 1782 | (condition-case nil |
| 1783 | (let* ((orig-win (selected-window)) |
| 1784 | (win (nth 0 (funcall |
| 1785 | (symbol-function 'event-start) event))) |
| 1786 | (fmode (assq 'follow-mode |
| 1787 | (buffer-local-variables |
| 1788 | (window-buffer win))))) |
| 1789 | (if (and fmode (cdr fmode)) |
| 1790 | ;; The selected window is in follow-mode |
| 1791 | (progn |
| 1792 | ;; Recenter around the dragged window. |
| 1793 | (select-window win) |
| 1794 | (follow-redisplay) |
| 1795 | (select-window orig-win)))) |
| 1796 | (error nil)))) |
| 1797 | |
| 1798 | |
| 1799 | ((fboundp 'scrollbar-vertical-drag) |
| 1800 | ;;; |
| 1801 | ;;; XEmacs style scrollbars. |
| 1802 | ;;; |
| 1803 | |
| 1804 | ;; Advice all scrollbar functions on the form: |
| 1805 | ;; |
| 1806 | ;; (defadvice scrollbar-line-down |
| 1807 | ;; (after follow-scrollbar-line-down activate) |
| 1808 | ;; (follow-xemacs-scrollbar-support (ad-get-arg 0))) |
| 1809 | |
| 1810 | (let ((cmds '(scrollbar-line-down ; Window |
| 1811 | scrollbar-line-up |
| 1812 | scrollbar-page-down ; Object |
| 1813 | scrollbar-page-up |
| 1814 | scrollbar-to-bottom ; Window |
| 1815 | scrollbar-to-top |
| 1816 | scrollbar-vertical-drag ; Object |
| 1817 | ))) |
| 1818 | |
| 1819 | (while cmds |
| 1820 | (eval |
| 1821 | `(defadvice ,(intern (symbol-name (car cmds))) |
| 1822 | (after |
| 1823 | ,(intern (concat "follow-" (symbol-name (car cmds)))) |
| 1824 | activate) |
| 1825 | "Adviced by `follow-mode'." |
| 1826 | (follow-xemacs-scrollbar-support (ad-get-arg 0)))) |
| 1827 | (setq cmds (cdr cmds)))) |
| 1828 | |
| 1829 | |
| 1830 | (defun follow-xemacs-scrollbar-support (window) |
| 1831 | "Redraw windows showing the same buffer as shown in WINDOW. |
| 1832 | WINDOW is either the dragged window, or a cons containing the |
| 1833 | window as its first element. This is called while the user drags |
| 1834 | the scrollbar. |
| 1835 | |
| 1836 | WINDOW can be an object or a window." |
| 1837 | (condition-case nil |
| 1838 | (progn |
| 1839 | (if (consp window) |
| 1840 | (setq window (car window))) |
| 1841 | (let ((fmode (assq 'follow-mode |
| 1842 | (buffer-local-variables |
| 1843 | (window-buffer window)))) |
| 1844 | (orig-win (selected-window))) |
| 1845 | (if (and fmode (cdr fmode)) |
| 1846 | (progn |
| 1847 | ;; Recenter around the dragged window. |
| 1848 | (select-window window) |
| 1849 | (follow-redisplay) |
| 1850 | (select-window orig-win))))) |
| 1851 | (error nil))))) |
| 1852 | |
| 1853 | ;;}}} |
| 1854 | ;;{{{ Process output |
| 1855 | |
| 1856 | ;;; The following sections installs a spy that listens to process |
| 1857 | ;;; output and tries to reposition the windows whose buffers are in |
| 1858 | ;;; Follow mode. We play safe as much as possible... |
| 1859 | ;;; |
| 1860 | ;;; When follow-mode is activated all active processes are |
| 1861 | ;;; intercepted. All new processes that change their filter function |
| 1862 | ;;; using `set-process-filter' are also intercepted. The reason is |
| 1863 | ;;; that a process can cause a redisplay recentering "tail" windows. |
| 1864 | ;;; Note that it doesn't hurt to spy on more processes than needed. |
| 1865 | ;;; |
| 1866 | ;;; Technically, we set the process filter to `follow-generic-filter'. |
| 1867 | ;;; The original filter is stored in `follow-process-filter-alist'. |
| 1868 | ;;; Our generic filter calls the original filter, or inserts the |
| 1869 | ;;; output into the buffer, if the buffer originally didn't have an |
| 1870 | ;;; output filter. It also makes sure that the windows connected to |
| 1871 | ;;; the buffer are aligned. |
| 1872 | ;;; |
| 1873 | ;;; Discussion: How do we find processes that don't call |
| 1874 | ;;; `set-process-filter'? (How often are processes created in a |
| 1875 | ;;; buffer after Follow mode are activated?) |
| 1876 | ;;; |
| 1877 | ;;; Discussion: Should we also advice `process-filter' to make our |
| 1878 | ;;; filter invisible to others? |
| 1879 | |
| 1880 | ;;{{{ Advice for `set-process-filter' |
| 1881 | |
| 1882 | ;; Do not call this with 'follow-generic-filter as the name of the |
| 1883 | ;; filter... |
| 1884 | |
| 1885 | (defadvice set-process-filter (before follow-set-process-filter activate) |
| 1886 | "Ensure process output will be displayed correctly in Follow Mode buffers. |
| 1887 | |
| 1888 | Follow Mode inserts its own process filter to do its |
| 1889 | magic stuff before the real process filter is called." |
| 1890 | (if follow-intercept-processes |
| 1891 | (progn |
| 1892 | (setq follow-process-filter-alist |
| 1893 | (delq (assq (ad-get-arg 0) follow-process-filter-alist) |
| 1894 | follow-process-filter-alist)) |
| 1895 | (follow-tidy-process-filter-alist) |
| 1896 | (cond ((eq (ad-get-arg 1) t)) |
| 1897 | ((eq (ad-get-arg 1) nil) |
| 1898 | (ad-set-arg 1 'follow-generic-filter)) |
| 1899 | (t |
| 1900 | (setq follow-process-filter-alist |
| 1901 | (cons (cons (ad-get-arg 0) (ad-get-arg 1)) |
| 1902 | follow-process-filter-alist)) |
| 1903 | (ad-set-arg 1 'follow-generic-filter)))))) |
| 1904 | |
| 1905 | |
| 1906 | (defun follow-call-set-process-filter (proc filter) |
| 1907 | "Call original `set-process-filter' without the Follow mode advice." |
| 1908 | (ad-disable-advice 'set-process-filter 'before |
| 1909 | 'follow-set-process-filter) |
| 1910 | (ad-activate 'set-process-filter) |
| 1911 | (prog1 |
| 1912 | (set-process-filter proc filter) |
| 1913 | (ad-enable-advice 'set-process-filter 'before |
| 1914 | 'follow-set-process-filter) |
| 1915 | (ad-activate 'set-process-filter))) |
| 1916 | |
| 1917 | |
| 1918 | (defadvice process-filter (after follow-process-filter activate) |
| 1919 | "Return the original process filter, not `follow-generic-filter'." |
| 1920 | (cond ((eq ad-return-value 'follow-generic-filter) |
| 1921 | (setq ad-return-value |
| 1922 | (cdr-safe (assq (ad-get-arg 0) |
| 1923 | follow-process-filter-alist)))))) |
| 1924 | |
| 1925 | |
| 1926 | (defun follow-call-process-filter (proc) |
| 1927 | "Call original `process-filter' without the Follow mode advice." |
| 1928 | (ad-disable-advice 'process-filter 'after |
| 1929 | 'follow-process-filter) |
| 1930 | (ad-activate 'process-filter) |
| 1931 | (prog1 |
| 1932 | (process-filter proc) |
| 1933 | (ad-enable-advice 'process-filter 'after |
| 1934 | 'follow-process-filter) |
| 1935 | (ad-activate 'process-filter))) |
| 1936 | |
| 1937 | |
| 1938 | (defun follow-tidy-process-filter-alist () |
| 1939 | "Remove old processes from `follow-process-filter-alist'." |
| 1940 | (let ((alist follow-process-filter-alist) |
| 1941 | (ps (process-list)) |
| 1942 | (new ())) |
| 1943 | (while alist |
| 1944 | (if (and (not (memq (process-status (car (car alist))) |
| 1945 | '(exit signal closed nil))) |
| 1946 | (memq (car (car alist)) ps)) |
| 1947 | (setq new (cons (car alist) new))) |
| 1948 | (setq alist (cdr alist))) |
| 1949 | (setq follow-process-filter-alist new))) |
| 1950 | |
| 1951 | ;;}}} |
| 1952 | ;;{{{ Start/stop interception of processes. |
| 1953 | |
| 1954 | ;; Normally, all new processed are intercepted by our `set-process-filter'. |
| 1955 | ;; This is needed to intercept old processed that were started before we were |
| 1956 | ;; loaded, and processes we have forgotten by calling |
| 1957 | ;; `follow-stop-intercept-process-output'. |
| 1958 | |
| 1959 | (defun follow-intercept-process-output () |
| 1960 | "Intercept all active processes. |
| 1961 | |
| 1962 | This is needed so that Follow Mode can track all display events in the |
| 1963 | system. (See `follow-mode')" |
| 1964 | (interactive) |
| 1965 | (let ((list (process-list))) |
| 1966 | (while list |
| 1967 | (if (eq (process-filter (car list)) 'follow-generic-filter) |
| 1968 | nil |
| 1969 | ;; The custom `set-process-filter' defined above. |
| 1970 | (set-process-filter (car list) (process-filter (car list)))) |
| 1971 | (setq list (cdr list)))) |
| 1972 | (setq follow-intercept-processes t)) |
| 1973 | |
| 1974 | |
| 1975 | (defun follow-stop-intercept-process-output () |
| 1976 | "Stop Follow Mode from spying on processes. |
| 1977 | |
| 1978 | All current spypoints are removed and no new will be added. |
| 1979 | |
| 1980 | The effect is that Follow mode won't be able to handle buffers |
| 1981 | connected to processes. |
| 1982 | |
| 1983 | The only reason to call this function is if the Follow mode spy filter |
| 1984 | would interfere with some other package. If this happens, please |
| 1985 | report this using the `follow-submit-feedback' function." |
| 1986 | (interactive) |
| 1987 | (follow-tidy-process-filter-alist) |
| 1988 | (let ((list (process-list))) |
| 1989 | (while list |
| 1990 | (if (eq (process-filter (car list)) 'follow-generic-filter) |
| 1991 | (progn |
| 1992 | (follow-call-set-process-filter |
| 1993 | (car list) |
| 1994 | (cdr-safe (assq (car list) follow-process-filter-alist))) |
| 1995 | (setq follow-process-filter-alist |
| 1996 | (delq (assq (car list) follow-process-filter-alist) |
| 1997 | follow-process-filter-alist)))) |
| 1998 | (setq list (cdr list)))) |
| 1999 | (setq follow-intercept-processes nil)) |
| 2000 | |
| 2001 | ;;}}} |
| 2002 | ;;{{{ The filter |
| 2003 | |
| 2004 | ;;; The following section is a naive method to make buffers with |
| 2005 | ;;; process output to work with Follow mode. Whenever the start of the |
| 2006 | ;;; window displaying the buffer is moved, we moves it back to its |
| 2007 | ;;; original position and try to select a new window. (If we fail, |
| 2008 | ;;; the normal redisplay functions of Emacs will scroll it right |
| 2009 | ;;; back!) |
| 2010 | |
| 2011 | (defun follow-generic-filter (proc output) |
| 2012 | "Process output filter for process connected to buffers in Follow mode." |
| 2013 | (let* ((old-buffer (current-buffer)) |
| 2014 | (orig-win (selected-window)) |
| 2015 | (buf (process-buffer proc)) |
| 2016 | (win (and buf (if (eq buf (window-buffer orig-win)) |
| 2017 | orig-win |
| 2018 | (get-buffer-window buf t)))) |
| 2019 | (return-to-orig-win (and win (not (eq win orig-win)))) |
| 2020 | (orig-window-start (and win (window-start win)))) |
| 2021 | |
| 2022 | ;; If input is pending, the `sit-for' below won't redraw the |
| 2023 | ;; display. In that case, calling `follow-avoid-tail-recenter' may |
| 2024 | ;; provoke the process hadnling code to sceduling a redisplay. |
| 2025 | ;(or (input-pending-p) |
| 2026 | ; (follow-avoid-tail-recenter)) |
| 2027 | |
| 2028 | ;; Output the `output'. |
| 2029 | (let ((filter (cdr-safe (assq proc follow-process-filter-alist)))) |
| 2030 | (cond |
| 2031 | ;; Call the original filter function |
| 2032 | (filter |
| 2033 | (funcall filter proc output)) |
| 2034 | |
| 2035 | ;; No filter, but we've got a buffer. Just output into it. |
| 2036 | (buf |
| 2037 | (set-buffer buf) |
| 2038 | (if (not (marker-buffer (process-mark proc))) |
| 2039 | (set-marker (process-mark proc) (point-max))) |
| 2040 | (let ((moving (= (point) (process-mark proc))) |
| 2041 | (odeactivate (and (boundp 'deactivate-mark) |
| 2042 | (symbol-value 'deactivate-mark))) |
| 2043 | (old-buffer-read-only buffer-read-only)) |
| 2044 | (setq buffer-read-only nil) |
| 2045 | (save-excursion |
| 2046 | (goto-char (process-mark proc)) |
| 2047 | ;; `insert-before-markers' just in case the users next |
| 2048 | ;; command is M-y. |
| 2049 | (insert-before-markers output) |
| 2050 | (set-marker (process-mark proc) (point))) |
| 2051 | (if moving (goto-char (process-mark proc))) |
| 2052 | (if (boundp 'deactivate-mark) |
| 2053 | ;; This could really be |
| 2054 | ;; (setq deactivate-mark odeactivate) |
| 2055 | ;; but this raises an error when compiling on XEmacs. |
| 2056 | (funcall (symbol-function 'set) |
| 2057 | 'deactivate-mark odeactivate)) |
| 2058 | (setq buffer-read-only old-buffer-read-only))))) |
| 2059 | |
| 2060 | ;; If we're in follow mode, do our stuff. Select a new window and |
| 2061 | ;; redisplay. (Actually, it is redundant to check `buf', but I |
| 2062 | ;; feel it's more correct.) |
| 2063 | (if (and buf win (window-live-p win)) |
| 2064 | (progn |
| 2065 | (set-buffer buf) |
| 2066 | (if (and (boundp 'follow-mode) follow-mode) |
| 2067 | (progn |
| 2068 | (select-window win) |
| 2069 | (let* ((windows (follow-all-followers win)) |
| 2070 | (win-start-end (follow-windows-start-end windows)) |
| 2071 | (new-window-start (window-start win)) |
| 2072 | (new-window-point (window-point win))) |
| 2073 | (cond |
| 2074 | ;; The window was moved. Move it back and |
| 2075 | ;; select a new. If no better could be found, |
| 2076 | ;; we stick the the new start position. This |
| 2077 | ;; is used when the original process filter |
| 2078 | ;; tries to position the cursor at the bottom |
| 2079 | ;; of the window. Example: `lyskom'. |
| 2080 | ((not (eq orig-window-start new-window-start)) |
| 2081 | (follow-debug-message "filter: Moved") |
| 2082 | (set-window-start win orig-window-start) |
| 2083 | (follow-redisplay windows win) |
| 2084 | (setq win-start-end (follow-windows-start-end windows)) |
| 2085 | (follow-select-if-visible new-window-point |
| 2086 | win-start-end) |
| 2087 | (goto-char new-window-point) |
| 2088 | (if (eq win (selected-window)) |
| 2089 | (set-window-start win new-window-start)) |
| 2090 | (setq win-start-end (follow-windows-start-end windows))) |
| 2091 | ;; Stick to this window, if point is visible in it. |
| 2092 | ((pos-visible-in-window-p new-window-point) |
| 2093 | (follow-debug-message "filter: Visible in window")) |
| 2094 | ;; Avoid redisplaying the first window. If the |
| 2095 | ;; point is visible at a window below, |
| 2096 | ;; redisplay and select it. |
| 2097 | ((follow-select-if-visible-from-first |
| 2098 | new-window-point windows) |
| 2099 | (follow-debug-message "filter: Seen from first") |
| 2100 | (follow-redisplay windows (car windows)) |
| 2101 | (goto-char new-window-point) |
| 2102 | (setq win-start-end |
| 2103 | (follow-windows-start-end windows))) |
| 2104 | ;; None of the above. We stick to the current window. |
| 2105 | (t |
| 2106 | (follow-debug-message "filter: nothing"))) |
| 2107 | |
| 2108 | ;; Here we have slected a window. Make sure the |
| 2109 | ;; windows are aligned and the point is visible |
| 2110 | ;; in the selected window. |
| 2111 | (if (and (not (follow-pos-visible |
| 2112 | (point) (selected-window) win-start-end)) |
| 2113 | (not return-to-orig-win)) |
| 2114 | (progn |
| 2115 | (sit-for 0) |
| 2116 | (setq win-start-end |
| 2117 | (follow-windows-start-end windows)))) |
| 2118 | |
| 2119 | (if (or follow-internal-force-redisplay |
| 2120 | (not (follow-windows-aligned-p win-start-end))) |
| 2121 | (follow-redisplay windows))))))) |
| 2122 | |
| 2123 | ;; return to the original window. |
| 2124 | (if return-to-orig-win |
| 2125 | (select-window orig-win)) |
| 2126 | ;; Restore the orignal buffer, unless the filter explicitly |
| 2127 | ;; changed buffer or killed the old buffer. |
| 2128 | (if (and (eq buf (current-buffer)) |
| 2129 | (buffer-name old-buffer)) |
| 2130 | (set-buffer old-buffer))) |
| 2131 | |
| 2132 | (follow-invalidate-cache) |
| 2133 | |
| 2134 | ;; Normally, if the display has been changed, it is redrawn. All |
| 2135 | ;; windows showing only the end of a buffer is unconditionally |
| 2136 | ;; recentered, we can't prevent it by calling |
| 2137 | ;; `follow-avoid-tail-recenter'. |
| 2138 | ;; |
| 2139 | ;; By performing a redisplay on our own, Emacs need not perform |
| 2140 | ;; the above described redisplay. (However, bu performing it when |
| 2141 | ;; there are input available just seems to make things worse.) |
| 2142 | (if (and follow-avoid-tail-recenter-p |
| 2143 | (not (input-pending-p))) |
| 2144 | (sit-for 0))) |
| 2145 | |
| 2146 | ;;}}} |
| 2147 | |
| 2148 | ;;}}} |
| 2149 | ;;{{{ Window size change |
| 2150 | |
| 2151 | ;; In Emacs 19.29, the functions in `window-size-change-functions' are |
| 2152 | ;; called every time a window in a frame changes size. Most notably, it |
| 2153 | ;; is called after the frame has been resized. |
| 2154 | ;; |
| 2155 | ;; We basically call our post-command-hook for every buffer that is |
| 2156 | ;; visible in any window in the resized frame, which is in follow-mode. |
| 2157 | ;; |
| 2158 | ;; Since this function can be called indirectly from |
| 2159 | ;; `follow-post-command-hook' we have a potential infinite loop. We |
| 2160 | ;; handle this problem by simply not doing anything at all in this |
| 2161 | ;; situation. The variable `follow-inside-post-command-hook' contains |
| 2162 | ;; information about whether the execution actually is inside the |
| 2163 | ;; post-command-hook or not. |
| 2164 | |
| 2165 | (if (boundp 'window-size-change-functions) |
| 2166 | (add-hook 'window-size-change-functions 'follow-window-size-change)) |
| 2167 | |
| 2168 | |
| 2169 | (defun follow-window-size-change (frame) |
| 2170 | "Redraw all windows in FRAME, when in Follow mode." |
| 2171 | ;; Below, we call `post-command-hook'. This makes sure that we |
| 2172 | ;; doesn't start a mutally recursive endless loop. |
| 2173 | (if follow-inside-post-command-hook |
| 2174 | nil |
| 2175 | (let ((buffers '()) |
| 2176 | (orig-window (selected-window)) |
| 2177 | (orig-buffer (current-buffer)) |
| 2178 | (orig-frame (selected-frame)) |
| 2179 | windows |
| 2180 | buf) |
| 2181 | (select-frame frame) |
| 2182 | (unwind-protect |
| 2183 | (walk-windows |
| 2184 | (function |
| 2185 | (lambda (win) |
| 2186 | (setq buf (window-buffer win)) |
| 2187 | (if (memq buf buffers) |
| 2188 | nil |
| 2189 | (set-buffer buf) |
| 2190 | (if (and (boundp 'follow-mode) |
| 2191 | follow-mode) |
| 2192 | (progn |
| 2193 | (setq windows (follow-all-followers win)) |
| 2194 | (if (memq orig-window windows) |
| 2195 | (progn |
| 2196 | ;; Make sure we're redrawing around the |
| 2197 | ;; selected window. |
| 2198 | ;; |
| 2199 | ;; We must be really careful not to do this |
| 2200 | ;; when we are (indirectly) called by |
| 2201 | ;; `post-command-hook'. |
| 2202 | (select-window orig-window) |
| 2203 | (follow-post-command-hook) |
| 2204 | (setq orig-window (selected-window))) |
| 2205 | (follow-redisplay windows win)) |
| 2206 | (setq buffers (cons buf buffers)))))))) |
| 2207 | (select-frame orig-frame) |
| 2208 | (set-buffer orig-buffer) |
| 2209 | (select-window orig-window))))) |
| 2210 | |
| 2211 | ;;}}} |
| 2212 | |
| 2213 | ;;{{{ XEmacs isearch |
| 2214 | |
| 2215 | ;; In XEmacs, isearch often finds matches in other windows than the |
| 2216 | ;; currently selected. However, when exiting the old window |
| 2217 | ;; configuration is restored, with the exception of the beginning of |
| 2218 | ;; the start of the window for the selected window. This is not much |
| 2219 | ;; help for us. |
| 2220 | ;; |
| 2221 | ;; We overwrite the stored window configuration with the current, |
| 2222 | ;; unless we are in `slow-search-mode', i.e. only a few lines |
| 2223 | ;; of text is visible. |
| 2224 | |
| 2225 | (if follow-emacs-version-xemacs-p |
| 2226 | (defadvice isearch-done (before follow-isearch-done activate) |
| 2227 | (if (and (boundp 'follow-mode) |
| 2228 | follow-mode |
| 2229 | (boundp 'isearch-window-configuration) |
| 2230 | isearch-window-configuration |
| 2231 | (boundp 'isearch-slow-terminal-mode) |
| 2232 | (not isearch-slow-terminal-mode)) |
| 2233 | (let ((buf (current-buffer))) |
| 2234 | (setq isearch-window-configuration |
| 2235 | (current-window-configuration)) |
| 2236 | (set-buffer buf))))) |
| 2237 | |
| 2238 | ;;}}} |
| 2239 | ;;{{{ Tail window handling |
| 2240 | |
| 2241 | ;;; In Emacs (not XEmacs) windows showing nothing are sometimes |
| 2242 | ;;; recentered. When in Follow Mode, this is not desireable for |
| 2243 | ;;; non-first windows in the window chain. This section tries to |
| 2244 | ;;; make the windows stay where they should be. |
| 2245 | ;;; |
| 2246 | ;;; If the display is updated, all windows starting at (point-max) are |
| 2247 | ;;; going to be recentered at the next redisplay, unless we do a |
| 2248 | ;;; read-and-write cycle to update the `force' flag inside the windows. |
| 2249 | ;;; |
| 2250 | ;;; In 19.30, a new varible `window-scroll-functions' is called every |
| 2251 | ;;; time a window is recentered. It is not perfect for our situation, |
| 2252 | ;;; since when it is called for a tail window, it is to late. However, |
| 2253 | ;;; if it is called for another window, we can try to update our |
| 2254 | ;;; windows. |
| 2255 | ;;; |
| 2256 | ;;; By patching `sit-for' we can make sure that to catch all explicit |
| 2257 | ;;; updates initiated by lisp programs. Internal calls, on the other |
| 2258 | ;;; hand, are not handled. |
| 2259 | ;;; |
| 2260 | ;;; Please note that the function `follow-avoid-tail-recenter' is also |
| 2261 | ;;; called from other places, e.g. `post-command-hook' and |
| 2262 | ;;; `post-command-idle-hook'. |
| 2263 | |
| 2264 | ;; If this function is called it is too late for this window, but |
| 2265 | ;; we might save other windows from being recentered. |
| 2266 | |
| 2267 | (if (and follow-avoid-tail-recenter-p (boundp 'window-scroll-functions)) |
| 2268 | (add-hook 'window-scroll-functions 'follow-avoid-tail-recenter t)) |
| 2269 | |
| 2270 | |
| 2271 | ;; This prevents all packages that calls `sit-for' directly |
| 2272 | ;; to recenter tail windows. |
| 2273 | |
| 2274 | (if follow-avoid-tail-recenter-p |
| 2275 | (defadvice sit-for (before follow-sit-for activate) |
| 2276 | "Adviced by Follow Mode. |
| 2277 | |
| 2278 | Avoid to recenter windows displaying only the end of a file as when |
| 2279 | displaying a short file in two windows, using Follow Mode." |
| 2280 | (follow-avoid-tail-recenter))) |
| 2281 | |
| 2282 | |
| 2283 | ;; Without this advice, `mouse-drag-region' would start to recenter |
| 2284 | ;; tail windows. |
| 2285 | |
| 2286 | (if (and follow-avoid-tail-recenter-p |
| 2287 | (fboundp 'move-overlay)) |
| 2288 | (defadvice move-overlay (before follow-move-overlay activate) |
| 2289 | "Adviced by Follow Mode. |
| 2290 | Don't recenter windows showing only the end of a buffer. |
| 2291 | This prevents `mouse-drag-region' from messing things up." |
| 2292 | (follow-avoid-tail-recenter))) |
| 2293 | |
| 2294 | ;;}}} |
| 2295 | ;;{{{ profile support |
| 2296 | |
| 2297 | ;; The following (non-evaluated) section can be used to |
| 2298 | ;; profile this package using `elp'. |
| 2299 | ;; |
| 2300 | ;; Invalid indentation on purpose! |
| 2301 | |
| 2302 | (cond (nil |
| 2303 | (setq elp-function-list |
| 2304 | '(window-end |
| 2305 | vertical-motion |
| 2306 | ; sit-for ;; elp can't handle advices... |
| 2307 | follow-mode |
| 2308 | follow-all-followers |
| 2309 | follow-split-followers |
| 2310 | follow-redisplay |
| 2311 | follow-downward |
| 2312 | follow-calculate-first-window-start |
| 2313 | follow-estimate-first-window-start |
| 2314 | follow-calculate-first-window-start-from-above |
| 2315 | follow-calculate-first-window-start-from-below |
| 2316 | follow-calc-win-end |
| 2317 | follow-calc-win-start |
| 2318 | follow-pos-visible |
| 2319 | follow-windows-start-end |
| 2320 | follow-cache-valid-p |
| 2321 | follow-select-if-visible |
| 2322 | follow-select-if-visible-from-first |
| 2323 | follow-windows-aligned-p |
| 2324 | follow-point-visible-all-windows-p |
| 2325 | follow-avoid-tail-recenter |
| 2326 | follow-update-window-start |
| 2327 | follow-post-command-hook |
| 2328 | )))) |
| 2329 | |
| 2330 | ;;}}} |
| 2331 | |
| 2332 | ;;{{{ The end |
| 2333 | |
| 2334 | ;;; |
| 2335 | ;;; We're done! |
| 2336 | ;;; |
| 2337 | |
| 2338 | (provide 'follow) |
| 2339 | |
| 2340 | ;;}}} |
| 2341 | |
| 2342 | ;; /------------------------------------------------------------------------\ |
| 2343 | ;; | "I [..] am rarely happier then when spending an entire day programming | |
| 2344 | ;; | my computer to perform automatically a task that it would otherwise | |
| 2345 | ;; | take me a good ten seconds to do by hand. Ten seconds, I tell myself, | |
| 2346 | ;; | is ten seconds. Time is valuable and ten seconds' worth of it is well | |
| 2347 | ;; | worth the investment of a day's happy activity working out a way to | |
| 2348 | ;; | save it". -- Douglas Adams, "Last Chance to See" | |
| 2349 | ;; \------------------------------------------------------------------------/ |
| 2350 | |
| 2351 | ;;; follow.el ends here |