diff options
Diffstat (limited to 'lisp/hscroll.el')
| -rw-r--r-- | lisp/hscroll.el | 233 |
1 files changed, 0 insertions, 233 deletions
diff --git a/lisp/hscroll.el b/lisp/hscroll.el deleted file mode 100644 index 7dd3674527d..00000000000 --- a/lisp/hscroll.el +++ /dev/null @@ -1,233 +0,0 @@ -;;; hscroll.el: Minor mode to automatically scroll truncated lines horizontally -;;; Copyright (C) 1992, 1993, 1995, 1996 Free Software Foundation, Inc. - -;; Author: Wayne Mesard <wmesard@esd.sgi.com> -;; Keywords: display - -;; This file is part of GNU Emacs. - -;; GNU Emacs is free software; you can redistribute it and/or modify -;; it under the terms of the GNU General Public License as published by -;; the Free Software Foundation; either version 2, or (at your option) -;; any later version. - -;; GNU Emacs is distributed in the hope that it will be useful, -;; but WITHOUT ANY WARRANTY; without even the implied warranty of -;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -;; GNU General Public License for more details. - -;; You should have received a copy of the GNU General Public License -;; along with GNU Emacs; see the file COPYING. If not, write to the -;; Free Software Foundation, Inc., 59 Temple Place - Suite 330, -;; Boston, MA 02111-1307, USA. - -;;; Commentary:a -;; -;; Automatically scroll horizontally when the point moves off the -;; left or right edge of the window. -;; -;; - Type "M-x hscroll-mode" to enable it in the current buffer. -;; - Type "M-x hscroll-global-mode" to enable it in every buffer. -;; - "turn-on-hscroll" is useful in mode hooks as in: -;; (add-hook 'text-mode-hook 'turn-on-hscroll) -;; -;; - hscroll-margin controls how close the cursor can get to the edge -;; of the window. -;; - hscroll-step-percent controls how far to jump once we decide to do so. -;; -;; Most users won't want to mess with the other variables defined -;; here. But they're all documented, and they all start with -;; "hscroll-" if you're curious. -;; -;; Oh, you should also know that if you set the hscroll-margin and -;; hscroll-step-percent large enough, you can get an interesting, but -;; undesired ping-pong effect as the point bounces from one edge to -;; the other. -;; -;; wmesard@sgi.com - -;;; Code: - -;;; -;;; PUBLIC VARIABLES -;;; - -(defvar hscroll-version "2.2") - -(defvar hscroll-margin 5 - "*How many columns away from the edge of the window point is allowed to get -before HScroll will horizontally scroll the window.") - -(defvar hscroll-snap-threshold 30 - "*When point is this many columns (or less) from the left edge of the document, -don't do any horizontal scrolling. In other words, be biased towards the left -edge of the document. - Set this variable to zero to disable this bias.") - -(defvar hscroll-step-percent 25 - "*How far away to place the point from the window's edge when scrolling. -Expressed as a percentage of the window's width.") - -(defvar hscroll-mode-name " Hscr" - "*Horizontal scrolling mode line indicator. -Set this to nil to conserve valuable mode line space.") - -(or (assq 'hscroll-mode minor-mode-alist) - (setq minor-mode-alist - (cons '(hscroll-mode hscroll-mode-name) minor-mode-alist))) - - -;;; -;;; PRIVATE VARIABLES -;;; - -(defvar hscroll-mode nil - "Non-nil if HScroll mode is enabled.") -(make-variable-buffer-local 'hscroll-mode) - - -(defvar hscroll-old-truncate-local nil) -(defvar hscroll-old-truncate-was-global nil) -(make-variable-buffer-local 'hscroll-old-truncate) -(make-variable-buffer-local 'hscroll-old-truncate-was-global) - -(defvar hscroll-old-truncate-default nil) - -;;; -;;; PUBLIC COMMANDS -;;; - -;;;###autoload -(defun turn-on-hscroll () - "Unconditionally turn on Hscroll mode in the current buffer." - (hscroll-mode 1)) - -;;;###autoload -(defun hscroll-mode (&optional arg) - "Toggle HScroll mode in the current buffer. -With ARG, turn HScroll mode on if ARG is positive, off otherwise. -In HScroll mode, truncated lines will automatically scroll left or -right when point gets near either edge of the window. - See also \\[hscroll-global-mode]." - (interactive "P") - (make-local-hook 'post-command-hook) - (let ((newmode (if (null arg) - (not hscroll-mode) - (> (prefix-numeric-value arg) 0)))) - - (if newmode - ;; turn it on - (if (not hscroll-mode) - ;; it was off - (let ((localp (local-variable-p 'truncate-lines))) - (if localp - (setq hscroll-old-truncate-local truncate-lines)) - (setq hscroll-old-truncate-was-global (not localp)) - (setq truncate-lines t) - (add-hook 'post-command-hook - (function hscroll-window-maybe) nil t) - )) - ;; turn it off - (if hscroll-mode - ;; it was on - (progn - (if hscroll-old-truncate-was-global - (kill-local-variable 'truncate-lines) - (setq truncate-lines hscroll-old-truncate-local)) - (if (not truncate-lines) - (set-window-hscroll (selected-window) 0)) - (remove-hook 'post-command-hook - (function hscroll-window-maybe) t) - )) - ) - - (setq hscroll-mode newmode) - (force-mode-line-update nil) - )) - - -;;;###autoload -(defun hscroll-global-mode (&optional arg) - "Toggle HScroll mode in all buffers. -With ARG, turn HScroll mode on if ARG is positive, off otherwise. -If a buffer ever has HScroll mode set locally (via \\[hscroll-mode]), -it will forever use the local value (i.e., \\[hscroll-global-mode] -will have no effect on it). - See also \\[hscroll-mode]." - (interactive "P") - (let* ((oldmode (default-value 'hscroll-mode)) - (newmode (if (null arg) - (not oldmode) - (> (prefix-numeric-value arg) 0)))) - - (if newmode - ;; turn it on - (if (not hscroll-mode) - ;; it was off - (progn - (setq hscroll-old-truncate-default (default-value truncate-lines)) - (setq hscroll-old-truncate-was-global t) - (setq-default truncate-lines t) - (add-hook 'post-command-hook (function hscroll-window-maybe)) - )) - ;; turn it off - (if hscroll-mode - ;; it was on - (progn - (setq-default truncate-lines hscroll-old-truncate-default) - (remove-hook 'post-command-hook (function hscroll-window-maybe)) - )) - ) - - (setq-default hscroll-mode newmode) - (force-mode-line-update t) - )) - -(defun hscroll-window-maybe () - "Scroll horizontally if point is off or nearly off the edge of the window. -This is called automatically when in HScroll mode, but it can be explicitly -invoked as well (i.e., it can be bound to a key)." - (interactive) - ;; Only consider scrolling if truncate-lines is true, - ;; the window is already scrolled or partial-widths is true and this is - ;; a partial width window. See display_text_line() in xdisp.c. - (if (and hscroll-mode - (or truncate-lines - (not (zerop (window-hscroll))) - (and truncate-partial-width-windows - (< (window-width) (frame-width))))) - (let ((linelen (save-excursion (end-of-line) (current-column))) - (rightmost-char (+ (window-width) (window-hscroll))) - ) - (if (< (current-column) hscroll-snap-threshold) - (set-window-hscroll - (selected-window) - (- (window-hscroll))) - (if (>= (current-column) - (- rightmost-char hscroll-margin - ;; Off-by-one if the left edge is scrolled - (if (not (zerop (window-hscroll))) 1 0) - ;; Off by one if the right edge is scrolled - (if (> linelen rightmost-char) 1 0) - )) - ;; Scroll to the left a proportion of the window's width. - (set-window-hscroll - (selected-window) - (- (+ (current-column) - (/ (* (window-width) hscroll-step-percent) 100)) - (window-width))) - (if (< (current-column) (+ (window-hscroll) hscroll-margin)) - ;; Scroll to the right a proportion of the window's width. - (set-window-hscroll - (selected-window) - (- (current-column) (/ (* (window-width) hscroll-step-percent) 100))) - ))) - ))) - -;;; -;;; It's not a bug, it's a *feature* -;;; - -(provide 'hscroll) - -;;; hscroll.el ends here |