;;; ehelp.el --- bindings for electric-help mode
-;; Copyright (C) 1986 Free Software Foundation, Inc.
+;; Copyright (C) 1986, 1995, 2000, 2001, 2002, 2003, 2004,
+;; 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
;; Maintainer: FSF
;; Keywords: help, extensions
;; 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)
+;; the Free Software Foundation; either version 3, or (at your option)
;; any later version.
;; GNU Emacs is distributed in the hope that it will be useful,
;; 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, 675 Mass Ave, Cambridge, MA 02139, USA.
+;; along with GNU Emacs; see the file COPYING. If not, write to the
+;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+;; Boston, MA 02110-1301, USA.
;;; Commentary:
;; This package provides a pre-packaged `Electric Help Mode' for
;; browsing on-line help screens. There is one entry point,
-;; `with-electric-help'; All you have to give it is a no-argument
-;; function that generates the actual text of the help into the urrent
+;; `with-electric-help'; all you have to give it is a no-argument
+;; function that generates the actual text of the help into the current
;; buffer.
+;; To make this the default, you must do
+;; (require 'ehelp)
+;; (define-key global-map "\C-h" 'ehelp-command)
+;; (define-key global-map [help] 'ehelp-command)
+;; (define-key global-map [f1] 'ehelp-command)
+
;;; Code:
(require 'electric)
(defvar electric-help-map ()
"Keymap defining commands available in `electric-help-mode'.")
+(defvar electric-help-form-to-execute nil)
+
+(defgroup electric-help ()
+ "Electric help facility."
+ :version "21.1"
+ :group 'help)
+
+(defcustom electric-help-shrink-window t
+ "If set, adjust help window sizes to buffer sizes when displaying help."
+ :type 'boolean
+ :group 'electric-help)
+
+(defcustom electric-help-mode-hook nil
+ "Hook run by `with-electric-help' after initializing the buffer."
+ :type 'hook
+ :group 'electric-help)
+
(put 'electric-help-undefined 'suppress-keymap t)
(if electric-help-map
()
(let ((map (make-keymap)))
- (fillarray (car (cdr map)) 'electric-help-undefined)
- (define-key map (char-to-string meta-prefix-char) (copy-keymap map))
+ ;; allow all non-self-inserting keys - search, scroll, etc, but
+ ;; let M-x and C-x exit ehelp mode and retain buffer:
+ (suppress-keymap map)
+ (define-key map "\C-u" 'electric-help-undefined)
+ (define-key map [?\C-0] 'electric-help-undefined)
+ (define-key map [?\C-1] 'electric-help-undefined)
+ (define-key map [?\C-2] 'electric-help-undefined)
+ (define-key map [?\C-3] 'electric-help-undefined)
+ (define-key map [?\C-4] 'electric-help-undefined)
+ (define-key map [?\C-5] 'electric-help-undefined)
+ (define-key map [?\C-6] 'electric-help-undefined)
+ (define-key map [?\C-7] 'electric-help-undefined)
+ (define-key map [?\C-8] 'electric-help-undefined)
+ (define-key map [?\C-9] 'electric-help-undefined)
(define-key map (char-to-string help-char) 'electric-help-help)
(define-key map "?" 'electric-help-help)
(define-key map " " 'scroll-up)
(define-key map "<" 'beginning-of-buffer)
(define-key map ">" 'end-of-buffer)
;(define-key map "\C-g" 'electric-help-exit)
- (define-key map "q" 'electric-help-exit)
(define-key map "Q" 'electric-help-exit)
+ (define-key map "q" 'electric-help-exit)
;;a better key than this?
+ (define-key map "R" 'electric-help-retain)
(define-key map "r" 'electric-help-retain)
+ (define-key map "\ex" 'electric-help-execute-extended)
+ (define-key map "\C-x" 'electric-help-ctrl-x-prefix)
(setq electric-help-map map)))
-
+
(defun electric-help-mode ()
"`with-electric-help' temporarily places its buffer in this mode.
\(On exit from `with-electric-help', the buffer is put in `default-major-mode'.)"
(setq major-mode 'help)
(setq mode-line-buffer-identification '(" Help: %b"))
(use-local-map electric-help-map)
+ (add-hook 'mouse-leave-buffer-hook 'electric-help-retain)
+ (view-mode -1)
;; this is done below in with-electric-help
;(run-hooks 'electric-help-mode-hook)
)
-(defun with-electric-help (thunk &optional buffer noerase)
- "Arguments are THUNK &optional BUFFER NOERASE. BUFFER defaults to \"*Help*\"
-THUNK is a function of no arguments which is called to initialize
-the contents of BUFFER. BUFFER will be erased before THUNK is called unless
-NOERASE is non-nil. THUNK will be called with `standard-output' bound to
-the buffer specified by BUFFER
+;;;###autoload
+(defun with-electric-help (thunk &optional buffer noerase minheight)
+ "Pop up an \"electric\" help buffer.
+THUNK is a function of no arguments which is called to initialize the
+contents of BUFFER. BUFFER defaults to `*Help*'. BUFFER will be
+erased before THUNK is called unless NOERASE is non-nil. THUNK will
+be called while BUFFER is current and with `standard-output' bound to
+the buffer specified by BUFFER.
+
+If THUNK returns nil, we display BUFFER starting at the top, and
+shrink the window to fit. If THUNK returns non-nil, we don't do those things.
After THUNK has been called, this function \"electrically\" pops up a window
in which BUFFER is displayed and allows the user to scroll through that buffer
-in electric-help-mode.
-When the user exits (with `electric-help-exit', or otherwise) the help
-buffer's window disappears (i.e., we use `save-window-excursion')
-BUFFER is put into `default-major-mode' (or `fundamental-mode') when we exit"
+in `electric-help-mode'. The window's height will be at least MINHEIGHT if
+this value is non-nil.
+
+If THUNK returns nil, we display BUFFER starting at the top, and
+shrink the window to fit if `electric-help-shrink-window' is non-nil.
+If THUNK returns non-nil, we don't do those things.
+
+When the user exits (with `electric-help-exit', or otherwise), the help
+buffer's window disappears (i.e., we use `save-window-excursion'), and
+BUFFER is put into `default-major-mode' (or `fundamental-mode')."
(setq buffer (get-buffer-create (or buffer "*Help*")))
(let ((one (one-window-p t))
(config (current-window-configuration))
- (bury nil))
+ (bury nil)
+ (electric-help-form-to-execute nil))
(unwind-protect
(save-excursion
- (if one (goto-char (window-start (selected-window))))
+ (when one
+ (goto-char (window-start (selected-window))))
(let ((pop-up-windows t))
(pop-to-buffer buffer))
(save-excursion
(set-buffer buffer)
+ (when (and minheight (< (window-height) minheight))
+ (enlarge-window (- minheight (window-height))))
(electric-help-mode)
- (setq buffer-read-only nil)
- (or noerase (erase-buffer)))
+ (setq buffer-read-only nil)
+ (unless noerase
+ (erase-buffer)))
(let ((standard-output buffer))
- (if (not (funcall thunk))
- (progn
- (set-buffer buffer)
- (set-buffer-modified-p nil)
- (goto-char (point-min))
- (if one (shrink-window-if-larger-than-buffer (selected-window))))))
+ (unless (funcall thunk)
+ (set-buffer buffer)
+ (set-buffer-modified-p nil)
+ (goto-char (point-min))
+ (when (and one electric-help-shrink-window)
+ (shrink-window-if-larger-than-buffer))))
(set-buffer buffer)
(run-hooks 'electric-help-mode-hook)
- (if (eq (car-safe (electric-help-command-loop))
- 'retain)
+ (setq buffer-read-only t)
+ (if (eq (car-safe (electric-help-command-loop)) 'retain)
(setq config (current-window-configuration))
- (setq bury t)))
+ (setq bury t))
+ ;; Remove the hook.
+ (when (memq 'electric-help-retain mouse-leave-buffer-hook)
+ (remove-hook 'mouse-leave-buffer-hook 'electric-help-retain)))
(message "")
(set-buffer buffer)
(setq buffer-read-only nil)
+
+ ;; We should really get a usable *Help* buffer when retaining
+ ;; the electric one with `r'. The problem is that a simple
+ ;; call to help-mode won't cut it; at least RET is bound wrong
+ ;; afterwards. It's also not clear that `help-mode' is always
+ ;; the right thing, maybe we should add an optional parameter.
(condition-case ()
(funcall (or default-major-mode 'fundamental-mode))
(error nil))
+
(set-window-configuration config)
- (if bury
- (progn
- ;;>> Perhaps this shouldn't be done.
- ;; so that when we say "Press space to bury" we mean it
- (replace-buffer-in-windows buffer)
- ;; must do this outside of save-window-excursion
- (bury-buffer buffer))))))
+ (when bury
+ ;;>> Perhaps this shouldn't be done,
+ ;; so that when we say "Press space to bury" we mean it
+ (replace-buffer-in-windows buffer)
+ ;; must do this outside of save-window-excursion
+ (bury-buffer buffer))
+ (eval electric-help-form-to-execute))))
(defun electric-help-command-loop ()
(catch 'exit
(if (pos-visible-in-window-p (point-max))
- (progn (message "<<< Press Space to bury the help buffer >>>")
+ (progn (message "%s" (substitute-command-keys "<<< Press Space to bury the help buffer, Press \\[electric-help-retain] to retain it >>>"))
(if (equal (setq unread-command-events (list (read-event)))
- '(?\ ))
+ '(?\s))
(progn (setq unread-command-events nil)
(throw 'exit t)))))
(let (up down both neither
- (standard (and (eq (key-binding " ")
+ (standard (and (eq (key-binding " " nil t)
'scroll-up)
- (eq (key-binding "\^?")
+ (eq (key-binding "\^?" nil t)
'scroll-down)
- (eq (key-binding "Q")
+ (eq (key-binding "q" nil t)
'electric-help-exit)
- (eq (key-binding "q")
- 'electric-help-exit))))
+ (eq (key-binding "r" nil t)
+ 'electric-help-retain))))
(Electric-command-loop
'exit
(function (lambda ()
+ (sit-for 0) ;necessary if last command was end-of-buffer or
+ ;beginning-of-buffer - otherwise pos-visible-in-window-p
+ ;will yield a wrong result.
(let ((min (pos-visible-in-window-p (point-min)))
- (max (pos-visible-in-window-p (point-max))))
- (cond ((and min max)
- (cond (standard "Press Q to exit ")
+ (max (pos-visible-in-window-p (1- (point-max)))))
+ (cond (isearch-mode 'noprompt)
+ ((and min max)
+ (cond (standard "Press q to exit, r to retain ")
(neither)
- (t (setq neither (substitute-command-keys "Press \\[scroll-up] to exit ")))))
+ (t (setq neither (substitute-command-keys "Press \\[electric-help-exit] to exit, \\[electric-help-retain] to retain ")))))
(min
- (cond (standard "Press SPC to scroll, Q to exit ")
+ (cond (standard "Press SPC to scroll, q to exit, r to retain ")
(up)
- (t (setq up (substitute-command-keys "Press \\[scroll-up] to scroll; \\[electric-help-exit] to exit ")))))
+ (t (setq up (substitute-command-keys "Press \\[scroll-up] to scroll, \\[electric-help-exit] to exit, \\[electric-help-retain] to retain ")))))
(max
- (cond (standard "Press DEL to scroll back, Q to exit ")
+ (cond (standard "Press DEL to scroll back, q to exit, r to retain ")
(down)
- (t (setq down (substitute-command-keys "Press \\[scroll-down] to scroll back, \\[scroll-up] to exit ")))))
+ (t (setq down (substitute-command-keys "Press \\[scroll-down] to scroll back, \\[electric-help-exit] to exit, \\[electric-help-retain] to retain ")))))
(t
- (cond (standard "Press SPC to scroll, DEL to scroll back, Q to exit ")
+ (cond (standard "Press SPC to scroll, DEL to scroll back, q to exit, r to retain ")
(both)
- (t (setq both (substitute-command-keys "Press \\[scroll-up] to scroll, \\[scroll-down] to scroll back, \\[electric-help-exit] to exit ")))))))))
+ (t (setq both (substitute-command-keys "Press \\[scroll-up] to scroll, \\[scroll-down] to scroll back, \\[electric-help-exit] to exit, \\[electric-help-retain] to retain ")))))))))
t))))
; (scroll-up arg)))
(defun electric-help-exit ()
- ">>>Doc"
+ "Exit `with-electric-help', restoring the previous window/buffer configuration.
+\(The *Help* buffer will be buried.)"
(interactive)
- (throw 'exit t))
+ ;; Make sure that we don't throw twice, even if two events cause
+ ;; calling this function:
+ (if (memq 'electric-help-retain mouse-leave-buffer-hook)
+ (progn
+ (remove-hook 'mouse-leave-buffer-hook 'electric-help-retain)
+ (throw 'exit t))))
(defun electric-help-retain ()
- "Exit `electric-help', retaining the current window/buffer configuration.
+ "Exit `with-electric-help', retaining the current window/buffer configuration.
\(The *Help* buffer will not be selected, but \\[switch-to-buffer-other-window] RET
will select it.)"
(interactive)
- (throw 'exit '(retain)))
+ ;; Make sure that we don't throw twice, even if two events cause
+ ;; calling this function:
+ (if (memq 'electric-help-retain mouse-leave-buffer-hook)
+ (progn
+ (remove-hook 'mouse-leave-buffer-hook 'electric-help-retain)
+ (throw 'exit '(retain)))))
(defun electric-help-undefined ()
(interactive)
(error "%s is undefined -- Press %s to exit"
(mapconcat 'single-key-description (this-command-keys) " ")
- (if (eq (key-binding "Q") 'electric-help-exit)
- "Q"
+ (if (eq (key-binding "q" nil t) 'electric-help-exit)
+ "q"
(substitute-command-keys "\\[electric-help-exit]"))))
;>>> this needs to be hairified (recursive help, anybody?)
(defun electric-help-help ()
(interactive)
- (if (and (eq (key-binding "Q") 'electric-help-exit)
- (eq (key-binding " ") 'scroll-up)
- (eq (key-binding "\^?") 'scroll-down))
- (message "SPC scrolls forward, DEL scrolls back, Q exits and burys help buffer")
- ;; to give something for user to look at while slow substitute-cmd-keys
- ;; grinds away
- (message "Help...")
- (message "%s" (substitute-command-keys "\\[scroll-up] scrolls forward, \\[scroll-down] scrolls back, \\[electric-help-exit] exits.")))
+ (if (and (eq (key-binding "q" nil t) 'electric-help-exit)
+ (eq (key-binding " " nil t) 'scroll-up)
+ (eq (key-binding "\^?" nil t) 'scroll-down)
+ (eq (key-binding "r" nil t) 'electric-help-retain))
+ (message "SPC scrolls up, DEL scrolls down, q exits burying help buffer, r exits")
+ (message "%s" (substitute-command-keys "\\[scroll-up] scrolls up, \\[scroll-down] scrolls down, \\[electric-help-exit] exits burying help buffer, \\[electric-help-retain] exits")))
(sit-for 2))
\f
-(defun electric-helpify (fun)
- (let ((name "*Help*"))
+;;;###autoload
+(defun electric-helpify (fun &optional name)
+ (let ((name (or name "*Help*")))
(if (save-window-excursion
;; kludge-o-rama
(let* ((p (symbol-function 'print-help-return-message))
(set-buffer-modified-p m))))))
(with-electric-help 'ignore name t))))
+\f
+
+;; This is to be bound to M-x in ehelp mode. Retains ehelp buffer and then
+;; continues with execute-extended-command.
+(defun electric-help-execute-extended (prefixarg)
+ (interactive "p")
+ (setq electric-help-form-to-execute '(execute-extended-command nil))
+ (electric-help-retain))
+
+;; This is to be buond to C-x in ehelp mode. Retains ehelp buffer and then
+;; continues with ctrl-x prefix.
+(defun electric-help-ctrl-x-prefix (prefixarg)
+ (interactive "p")
+ (setq electric-help-form-to-execute '(progn (message nil) (setq unread-command-char ?\C-x)))
+ (electric-help-retain))
+
\f
(defun electric-describe-key ()
(interactive)
(defun electric-command-apropos ()
(interactive)
- (electric-helpify 'command-apropos))
+ (electric-helpify 'command-apropos "*Apropos*"))
;(define-key help-map "a" 'electric-command-apropos)
+(defun electric-apropos ()
+ (interactive)
+ (electric-helpify 'apropos))
\f
;;;; ehelp-map
(defvar ehelp-map ())
(if ehelp-map
nil
- (let ((map (copy-keymap help-map)))
+ (let ((map (copy-keymap help-map)))
+ (substitute-key-definition 'apropos 'electric-apropos map)
+ (substitute-key-definition 'command-apropos 'electric-command-apropos map)
(substitute-key-definition 'describe-key 'electric-describe-key map)
(substitute-key-definition 'describe-mode 'electric-describe-mode map)
(substitute-key-definition 'view-lossage 'electric-view-lossage map)
(substitute-key-definition 'describe-bindings 'electric-describe-bindings map)
(substitute-key-definition 'describe-syntax 'electric-describe-syntax map)
- (setq ehelp-map map)
- (fset 'ehelp-command map)))
+ (setq ehelp-map map)))
-;; Do (define-key global-map "\C-h" 'ehelp-command) if you want to win
+;;;###(autoload 'ehelp-command "ehelp" "Prefix command for ehelp." t 'keymap)
+(defalias 'ehelp-command ehelp-map)
+(put 'ehelp-command 'documentation "Prefix command for ehelp.")
-(provide 'ehelp)
+(provide 'ehelp)
+;;; arch-tag: e0e3037f-42c0-433e-ba18-322c5d951f46
;;; ehelp.el ends here