;;; hl-line.el --- highlight the current line
-;; Copyright (C) 1998 Free Software Foundation, Inc.
+;; Copyright (C) 1998, 2000 Free Software Foundation, Inc.
;; Author: Dave Love <fx@gnu.org>
;; Created: 1998-09-13
-;; Keywords: faces, frames
+;; Keywords: faces, frames, emulation
-;; Hl-Line mode is free software; you can redistribute it and/or modify
+;; 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.
-;; Hl-Line mode is distributed in the hope that it will be useful,
+;; 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.
;;; Commentary:
;; Provides a global minor mode (toggled by M-x hl-line-mode) to
-;; highlight, in a windowing system, the line on which point is
-;; (except in a minibuffer window) to satisfy a request for a feature
-;; of Lesser Editors.
+;; highlight, on a suitable terminal, the line in the current window
+;; on which point is (except in a minibuffer window). Done to satisfy
+;; a request for a feature of Lesser Editors.
;; You probably don't really want this; if the cursor is difficult to
-;; spot, try changing its colour or using a cursor blinking
-;; <URL:http://www.wonderworks.com/download/blinking-cursor.el.gz> or
-;; jiggling <URL:http://www.eskimo.com/%7Eseldon> package. (Cursor
-;; blinking will be built in to Emacs 21.) The hookery involved here
-;; might slow Emacs noticeably on a slow machine.
+;; spot, try changing its colour, relying on `blink-cursor-mode' or
+;; both. The hookery used might affect response noticeably on a slow
+;; machine.
;; An overlay is used, active only on the selected window. Hooks are
;; added to `pre-command-hook' and `post-command-hook' to activate and
;; `hl-line-highlight', on `post-command-hook', activates it again
;; across the window width.
+;; You could make variable `hl-line-mode' buffer-local to avoid
+;; highlighting specific buffers.
+
;;; Code:
(defgroup hl-line nil
"Highliight the current line."
+ :version "21.1"
:group 'editing)
-(defcustom hl-line-mode nil
- "Non-nil if Hl-Line mode is enabled."
- :set (lambda (symbol value)
- (hl-line-mode (or value 0)))
- :initialize 'custom-initialize-default
- :type 'boolean
- :group 'hl-line
- :require 'hl-line)
-
(defcustom hl-line-face 'highlight
"Face with which to highlight the current line."
:type 'face
:group 'hl-line)
(defvar hl-line-overlay nil)
-(make-variable-buffer-local 'hl-line-overlay)
(defun hl-line-highlight ()
"Active the Hl-Line overlay on the current line in the current window.
\(Unless it's a minibuffer window.)"
- (unless (window-minibuffer-p (selected-window)) ; silly in minibuffer
- (unless hl-line-overlay ; new overlay for this buffer
- (setq hl-line-overlay (make-overlay 1 1)) ; to be moved
- (overlay-put hl-line-overlay 'face hl-line-face))
- (overlay-put hl-line-overlay 'window (selected-window))
- (move-overlay hl-line-overlay
- (line-beginning-position) (1+ (line-end-position)))))
+ (when hl-line-mode ; Could be made buffer-local.
+ (unless (window-minibuffer-p (selected-window)) ; silly in minibuffer
+ (unless hl-line-overlay
+ (setq hl-line-overlay (make-overlay 1 1)) ; to be moved
+ (overlay-put hl-line-overlay 'face hl-line-face))
+ (overlay-put hl-line-overlay 'window (selected-window))
+ (move-overlay hl-line-overlay
+ (line-beginning-position) (1+ (line-end-position))
+ (current-buffer)))))
(defun hl-line-unhighlight ()
"Deactivate the Hl-Line overlay on the current line in the current window."
(if hl-line-overlay
(delete-overlay hl-line-overlay)))
-(defun hl-line-mode (&optional arg)
- "Global minor mode to highlight the line about point.
-
+;;;###autoload
+(define-minor-mode hl-line-mode
+ "Global minor mode to highlight the line about point in the current window.
With ARG, turn Hl-Line mode on if ARG is positive, off otherwise.
-Only useful with a windowing system.
Uses functions `hl-line-unhighlight' and `hl-line-highlight' on
`pre-command-hook' and `post-command-hook'."
- (interactive "P")
- (setq hl-line-mode (if (null arg)
- (not hl-line-mode)
- (> (prefix-numeric-value arg) 0)))
- (cond (hl-line-mode
- (add-hook 'pre-command-hook #'hl-line-unhighlight)
- (add-hook 'post-command-hook #'hl-line-highlight))
- (t
- (hl-line-unhighlight)
- (remove-hook 'pre-command-hook #'hl-line-unhighlight)
- (remove-hook 'post-command-hook #'hl-line-highlight)))
- (if (interactive-p)
- (message "Hl-Line mode %sabled" (if hl-line-mode "en" "dis"))))
+ nil nil nil :global t
+
+ (if hl-line-mode
+ (progn
+ (add-hook 'pre-command-hook #'hl-line-unhighlight)
+ (add-hook 'post-command-hook #'hl-line-highlight))
+ (hl-line-unhighlight)
+ (remove-hook 'pre-command-hook #'hl-line-unhighlight)
+ (remove-hook 'post-command-hook #'hl-line-highlight)))
(provide 'hl-line)