Changes since 0.4:
,----
| - Introduce `global-less-minor-mode'.
| - Handle movement in image-mode specically.
| - Some bug fixes.
`----
-William
;;; less.el --- less style view mode
;; Copyright (C) 2005, 2007, 2009, 2010, 2011 William Xu
;; Author: William Xu <william.xwl <at> gmail.com>
;; Version: 0.5
;; This program 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 3, or (at your option)
;; any later version.
;;
;; This program 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 this program; if not, write to the Free Software
;; Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
;; 02110-1301 USA
;;; Commentary:
;; View file like a simple `less'. Provide limited less keys, mainly j,
;; k, f, b, g, G, etc.
;; Put this file into your load-path and the following into your ~/.emacs:
;; (require 'less)
;;
;; Then use `M-x less-minor-mode' to toggle `less-minor-mode'.
;; There's also a `view-less.el' in XEmacs. But it does too much for me,
;; i just wanna less keys like j, k, f, b, g, G, not to mess with other
;; keys in major mode.
;;; Code:
(defcustom auto-less-exclude-regexp
(regexp-opt
'("*Org Agenda*" "*code-conversion-work*" " *Compiler Input*"
" *Echo Area"
"*nntpd*" " *gnus work*" " *gnus article copy*"
" *extract address components*" " *canonical address*"
"*followup to" "*mail"))
"Do not turn on `auto-less-minor-mode' for matched files and buffers."
:type 'string
:group 'convenience)
(defcustom auto-less-exclude-modes
'(shell-mode term-mode comint-mode twittering-edit-mode calendar-mode
log-edit-mode gnus-summary-mode gnus-group-mode message-mode
dired-mode ibuffer-mode apropos-mode completion-list-mode
ediff-mode)
"Do not turn on `auto-less-minor-mode' for these major modes."
:type 'list
:group 'convenience)
;;;###autoload
(define-global-minor-mode global-less-minor-mode
less-minor-mode auto-less-minor-mode
:group 'convenience)
;;;###autoload
(define-minor-mode less-minor-mode
"Toggle less-minor-mode.
With less-minor-mode enabled, you could use `less' like keys to view files.
\\{less-minor-mode-map}"
nil " Less"
'(("j" . less-scroll-up-line)
("k" . less-scroll-down-line)
("f" . scroll-up)
("b" . scroll-down)
("g" . less-beginning-of-buffer)
("G" . less-end-of-buffer)
(" " . scroll-up)
("" . scroll-down)
("e" . less-quit))
(set (make-local-variable 'buffer-read-only) less-minor-mode))
;;;###autoload
(defun less-scroll-up-line ()
"Scroll up one line."
(interactive)
(if (eq major-mode 'image-mode)
(image-next-line 1)
(scroll-up 1)))
;;;###autoload
(defun less-scroll-down-line ()
"Scroll down one line."
(interactive)
(if (eq major-mode 'image-mode)
(image-previous-line 1)
(scroll-down 1)))
;;;###autoload
(defun less-beginning-of-buffer ()
(interactive)
(if (eq major-mode 'image-mode)
(image-bob)
(goto-char (point-min))))
;;;###autoload
(defun less-end-of-buffer ()
(interactive)
(if (eq major-mode 'image-mode)
(image-eob)
(goto-char (point-max))
;; Similar to `end-of-buffer'.
(recenter -3)))
;;;###autoload
(defun less-quit ()
"Quit `less-minor-mode'."
(interactive)
(less-minor-mode -1))
;;;###autoload
(defun auto-less-minor-mode ()
"Turn on `less-minor-mode' for files not matching `auto-less-exclude-regexp'.
This is a useful hook to add to `find-file-hook'."
(unless (or (and (not (string= auto-less-exclude-regexp ""))
(string-match auto-less-exclude-regexp
(or buffer-file-name (buffer-name))))
(memq major-mode auto-less-exclude-modes)
(minibufferp)
(not (if buffer-file-name (file-exists-p buffer-file-name) t)))
(less-minor-mode 1)))
;;;###autoload
(defun less-minor-mode-on ()
"Turn on `less-minor-mode'."
(less-minor-mode 1))
;;;###autoload
(defun less-minor-mode-off ()
"Turn off `less-minor-mode'."
(less-minor-mode -1))
(provide 'less)
;;; less.el ends here
