mirror of
https://git.savannah.gnu.org/git/emacs.git
synced 2024-11-24 07:20:37 +00:00
847 lines
32 KiB
EmacsLisp
847 lines
32 KiB
EmacsLisp
;;; help.el --- help commands for Emacs
|
||
|
||
;; Copyright (C) 1985, 1986, 1993, 1994, 1998, 1999, 2000, 2001, 2002, 2004
|
||
;; Free Software Foundation, Inc.
|
||
|
||
;; Maintainer: FSF
|
||
;; Keywords: help, internal
|
||
|
||
;; 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:
|
||
|
||
;; This code implements GNU Emacs' on-line help system, the one invoked by
|
||
;; `M-x help-for-help'.
|
||
|
||
;;; Code:
|
||
|
||
;; Get the macro make-help-screen when this is compiled,
|
||
;; or run interpreted, but not when the compiled code is loaded.
|
||
(eval-when-compile (require 'help-macro))
|
||
|
||
;; This makes `with-output-to-temp-buffer' buffers use `help-mode'.
|
||
(add-hook 'temp-buffer-setup-hook 'help-mode-setup)
|
||
(add-hook 'temp-buffer-show-hook 'help-mode-finish)
|
||
|
||
(defvar help-map (make-sparse-keymap)
|
||
"Keymap for characters following the Help key.")
|
||
|
||
(define-key global-map (char-to-string help-char) 'help-command)
|
||
(define-key global-map [help] 'help-command)
|
||
(define-key global-map [f1] 'help-command)
|
||
(fset 'help-command help-map)
|
||
|
||
(define-key help-map (char-to-string help-char) 'help-for-help)
|
||
(define-key help-map [help] 'help-for-help)
|
||
(define-key help-map [f1] 'help-for-help)
|
||
(define-key help-map "." 'display-local-help)
|
||
(define-key help-map "?" 'help-for-help)
|
||
|
||
(define-key help-map "\C-c" 'describe-copying)
|
||
(define-key help-map "\C-d" 'describe-distribution)
|
||
(define-key help-map "\C-e" 'view-emacs-problems)
|
||
(define-key help-map "\C-f" 'view-emacs-FAQ)
|
||
(define-key help-map "\C-m" 'view-order-manuals)
|
||
(define-key help-map "\C-n" 'view-emacs-news)
|
||
(define-key help-map "\C-p" 'describe-project)
|
||
(define-key help-map "\C-t" 'view-todo)
|
||
(define-key help-map "\C-w" 'describe-no-warranty)
|
||
|
||
;; This does not fit the pattern, but it is natural given the C-\ command.
|
||
(define-key help-map "\C-\\" 'describe-input-method)
|
||
|
||
(define-key help-map "C" 'describe-coding-system)
|
||
(define-key help-map "F" 'Info-goto-emacs-command-node)
|
||
(define-key help-map "I" 'describe-input-method)
|
||
(define-key help-map "K" 'Info-goto-emacs-key-command-node)
|
||
(define-key help-map "L" 'describe-language-environment)
|
||
(define-key help-map "S" 'info-lookup-symbol)
|
||
|
||
(define-key help-map "a" 'apropos-command)
|
||
|
||
(define-key help-map "b" 'describe-bindings)
|
||
|
||
(define-key help-map "c" 'describe-key-briefly)
|
||
|
||
(define-key help-map "e" 'view-echo-area-messages)
|
||
|
||
(define-key help-map "f" 'describe-function)
|
||
|
||
(define-key help-map "h" 'view-hello-file)
|
||
|
||
(define-key help-map "i" 'info)
|
||
(define-key help-map "4i" 'info-other-window)
|
||
|
||
(define-key help-map "k" 'describe-key)
|
||
|
||
(define-key help-map "l" 'view-lossage)
|
||
|
||
(define-key help-map "m" 'describe-mode)
|
||
|
||
(define-key help-map "n" 'view-emacs-news)
|
||
|
||
(define-key help-map "p" 'finder-by-keyword)
|
||
(autoload 'finder-by-keyword "finder"
|
||
"Find packages matching a given keyword." t)
|
||
|
||
(define-key help-map "r" 'info-emacs-manual)
|
||
|
||
(define-key help-map "s" 'describe-syntax)
|
||
|
||
(define-key help-map "t" 'help-with-tutorial)
|
||
|
||
(define-key help-map "w" 'where-is)
|
||
|
||
(define-key help-map "v" 'describe-variable)
|
||
|
||
(define-key help-map "q" 'help-quit)
|
||
|
||
;; insert-button makes the action nil if it is not store somewhere
|
||
(defvar help-button-cache nil)
|
||
|
||
|
||
(defun help-quit ()
|
||
"Just exit from the Help command's command loop."
|
||
(interactive)
|
||
nil)
|
||
|
||
(defvar help-return-method nil
|
||
"What to do to \"exit\" the help buffer.
|
||
This is a list
|
||
(WINDOW . t) delete the selected window, go to WINDOW.
|
||
(WINDOW . quit-window) do quit-window, then select WINDOW.
|
||
(WINDOW BUF START POINT) display BUF at START, POINT, then select WINDOW.")
|
||
|
||
(defun print-help-return-message (&optional function)
|
||
"Display or return message saying how to restore windows after help command.
|
||
This function assumes that `standard-output' is the help buffer.
|
||
It computes a message, and applies the optional argument FUNCTION to it.
|
||
If FUNCTION is nil, it applies `message', thus displaying the message."
|
||
(and (not (get-buffer-window standard-output))
|
||
(let ((first-message
|
||
(cond ((special-display-p (buffer-name standard-output))
|
||
(setq help-return-method (cons (selected-window) t))
|
||
;; If the help output buffer is a special display buffer,
|
||
;; don't say anything about how to get rid of it.
|
||
;; First of all, the user will do that with the window
|
||
;; manager, not with Emacs.
|
||
;; Secondly, the buffer has not been displayed yet,
|
||
;; so we don't know whether its frame will be selected.
|
||
nil)
|
||
(display-buffer-reuse-frames
|
||
(setq help-return-method (cons (selected-window)
|
||
'quit-window))
|
||
nil)
|
||
((not (one-window-p t))
|
||
(setq help-return-method
|
||
(cons (selected-window) 'quit-window))
|
||
"Type \\[switch-to-buffer-other-window] RET to restore the other window.")
|
||
(pop-up-windows
|
||
(setq help-return-method (cons (selected-window) t))
|
||
"Type \\[delete-other-windows] to remove help window.")
|
||
(t
|
||
(setq help-return-method
|
||
(list (selected-window) (window-buffer)
|
||
(window-start) (window-point)))
|
||
"Type \\[switch-to-buffer] RET to remove help window."))))
|
||
(funcall (or function 'message)
|
||
(concat
|
||
(if first-message
|
||
(substitute-command-keys first-message))
|
||
(if first-message " ")
|
||
;; If the help buffer will go in a separate frame,
|
||
;; it's no use mentioning a command to scroll, so don't.
|
||
(if (special-display-p (buffer-name standard-output))
|
||
nil
|
||
(if (same-window-p (buffer-name standard-output))
|
||
;; Say how to scroll this window.
|
||
(substitute-command-keys
|
||
"\\[scroll-up] to scroll the help.")
|
||
;; Say how to scroll some other window.
|
||
(substitute-command-keys
|
||
"\\[scroll-other-window] to scroll the help."))))))))
|
||
|
||
;; So keyboard macro definitions are documented correctly
|
||
(fset 'defining-kbd-macro (symbol-function 'start-kbd-macro))
|
||
|
||
(defalias 'help 'help-for-help)
|
||
(make-help-screen help-for-help
|
||
"a b c C e f F i I k C-k l L m p s t v w C-c C-d C-f C-n C-p C-t C-w . or ? :"
|
||
"You have typed %THIS-KEY%, the help character. Type a Help option:
|
||
\(Use SPC or DEL to scroll through this text. Type \\<help-map>\\[help-quit] to exit the Help command.)
|
||
|
||
a command-apropos. Give a substring, and see a list of commands
|
||
(functions interactively callable) that contain
|
||
that substring. See also the apropos command.
|
||
b describe-bindings. Display table of all key bindings.
|
||
c describe-key-briefly. Type a command key sequence;
|
||
it prints the function name that sequence runs.
|
||
C describe-coding-system. This describes either a specific coding system
|
||
(if you type its name) or the coding systems currently in use
|
||
(if you type just RET).
|
||
e view-echo-area-messages. Show the `*Messages*' buffer.
|
||
f describe-function. Type a function name and get documentation of it.
|
||
F Info-goto-emacs-command-node. Type a function name;
|
||
it takes you to the Info node for that command.
|
||
h Display the HELLO file which illustrates various scripts.
|
||
i info. The info documentation reader.
|
||
I describe-input-method. Describe a specific input method (if you type
|
||
its name) or the current input method (if you type just RET).
|
||
k describe-key. Type a command key sequence;
|
||
it displays the full documentation.
|
||
K Info-goto-emacs-key-command-node. Type a command key sequence;
|
||
it takes you to the Info node for the command bound to that key.
|
||
l view-lossage. Show last 100 characters you typed.
|
||
L describe-language-environment. This describes either a
|
||
specific language environment (if you type its name)
|
||
or the current language environment (if you type just RET).
|
||
m describe-mode. Print documentation of current minor modes,
|
||
and the current major mode, including their special commands.
|
||
p finder-by-keyword. Find packages matching a given topic keyword.
|
||
s describe-syntax. Display contents of syntax table, plus explanations.
|
||
S info-lookup-symbol. Display the definition of a specific symbol
|
||
as found in the manual for the language this buffer is written in.
|
||
t help-with-tutorial. Select the Emacs learn-by-doing tutorial.
|
||
v describe-variable. Type name of a variable;
|
||
it displays the variable's documentation and value.
|
||
w where-is. Type command name; it prints which keystrokes
|
||
invoke that command.
|
||
. display-local-help. Display any available local help at point
|
||
in the echo area.
|
||
|
||
C-c Display Emacs copying permission (GNU General Public License).
|
||
C-d Display Emacs ordering information.
|
||
C-e Display info about Emacs problems.
|
||
C-f Display the Emacs FAQ.
|
||
C-m Display how to order printed Emacs manuals.
|
||
C-n Display news of recent Emacs changes.
|
||
C-p Display information about the GNU project.
|
||
C-t Display the Emacs TODO list.
|
||
C-w Display information on absence of warranty for GNU Emacs."
|
||
help-map)
|
||
|
||
|
||
|
||
(defun function-called-at-point ()
|
||
"Return a function around point or else called by the list containing point.
|
||
If that doesn't give a function, return nil."
|
||
(or (with-syntax-table emacs-lisp-mode-syntax-table
|
||
(or (condition-case ()
|
||
(save-excursion
|
||
(or (not (zerop (skip-syntax-backward "_w")))
|
||
(eq (char-syntax (following-char)) ?w)
|
||
(eq (char-syntax (following-char)) ?_)
|
||
(forward-sexp -1))
|
||
(skip-chars-forward "'")
|
||
(let ((obj (read (current-buffer))))
|
||
(and (symbolp obj) (fboundp obj) obj)))
|
||
(error nil))
|
||
(condition-case ()
|
||
(save-excursion
|
||
(save-restriction
|
||
(narrow-to-region (max (point-min)
|
||
(- (point) 1000)) (point-max))
|
||
;; Move up to surrounding paren, then after the open.
|
||
(backward-up-list 1)
|
||
(forward-char 1)
|
||
;; If there is space here, this is probably something
|
||
;; other than a real Lisp function call, so ignore it.
|
||
(if (looking-at "[ \t]")
|
||
(error "Probably not a Lisp function call"))
|
||
(let ((obj (read (current-buffer))))
|
||
(and (symbolp obj) (fboundp obj) obj))))
|
||
(error nil))))
|
||
(let* ((str (find-tag-default))
|
||
(obj (if str (read str))))
|
||
(and (symbolp obj) (fboundp obj) obj))))
|
||
|
||
|
||
;;; `User' help functions
|
||
|
||
(defun describe-distribution ()
|
||
"Display info on how to obtain the latest version of GNU Emacs."
|
||
(interactive)
|
||
(view-file (expand-file-name "DISTRIB" data-directory)))
|
||
|
||
(defun describe-copying ()
|
||
"Display info on how you may redistribute copies of GNU Emacs."
|
||
(interactive)
|
||
(view-file (expand-file-name "COPYING" data-directory))
|
||
(goto-char (point-min)))
|
||
|
||
(defun describe-project ()
|
||
"Display info on the GNU project."
|
||
(interactive)
|
||
(view-file (expand-file-name "THE-GNU-PROJECT" data-directory))
|
||
(goto-char (point-min)))
|
||
|
||
(defun describe-no-warranty ()
|
||
"Display info on all the kinds of warranty Emacs does NOT have."
|
||
(interactive)
|
||
(describe-copying)
|
||
(let (case-fold-search)
|
||
(search-forward "NO WARRANTY")
|
||
(recenter 0)))
|
||
|
||
(defun describe-prefix-bindings ()
|
||
"Describe the bindings of the prefix used to reach this command.
|
||
The prefix described consists of all but the last event
|
||
of the key sequence that ran this command."
|
||
(interactive)
|
||
(let* ((key (this-command-keys)))
|
||
(describe-bindings
|
||
(if (stringp key)
|
||
(substring key 0 (1- (length key)))
|
||
(let ((prefix (make-vector (1- (length key)) nil))
|
||
(i 0))
|
||
(while (< i (length prefix))
|
||
(aset prefix i (aref key i))
|
||
(setq i (1+ i)))
|
||
prefix)))))
|
||
;; Make C-h after a prefix, when not specifically bound,
|
||
;; run describe-prefix-bindings.
|
||
(setq prefix-help-command 'describe-prefix-bindings)
|
||
|
||
(defun view-emacs-news (&optional arg)
|
||
"Display info on recent changes to Emacs.
|
||
With argument, display info only for the selected version."
|
||
(interactive "P")
|
||
(if (not arg)
|
||
(view-file (expand-file-name "NEWS" data-directory))
|
||
(let* ((map (sort
|
||
(delete-dups
|
||
(apply
|
||
'nconc
|
||
(mapcar
|
||
(lambda (file)
|
||
(with-temp-buffer
|
||
(insert-file-contents
|
||
(expand-file-name file data-directory))
|
||
(let (res)
|
||
(while (re-search-forward
|
||
(if (string-match "^ONEWS\\.[0-9]+$" file)
|
||
"Changes in \\(?:Emacs\\|version\\)?[ \t]*\\([0-9]+\\(?:\\.[0-9]+\\)?\\)"
|
||
"^\* [^0-9\n]*\\([0-9]+\\.[0-9]+\\)") nil t)
|
||
(setq res (cons (list (match-string-no-properties 1)
|
||
file) res)))
|
||
res)))
|
||
(append '("NEWS" "ONEWS")
|
||
(directory-files data-directory nil
|
||
"^ONEWS\\.[0-9]+$" nil)))))
|
||
(lambda (a b)
|
||
(string< (car b) (car a)))))
|
||
(current (caar map))
|
||
(version (completing-read
|
||
(format "Read NEWS for the version (default %s): " current)
|
||
(mapcar 'car map) nil nil nil nil current))
|
||
(file (cadr (assoc version map)))
|
||
res)
|
||
(if (not file)
|
||
(error "No news is good news")
|
||
(view-file (expand-file-name file data-directory))
|
||
(widen)
|
||
(goto-char (point-min))
|
||
(when (re-search-forward
|
||
(concat (if (string-match "^ONEWS\\.[0-9]+$" file)
|
||
"Changes in \\(?:Emacs\\|version\\)?[ \t]*"
|
||
"^\* [^0-9\n]*") version)
|
||
nil t)
|
||
(beginning-of-line)
|
||
(narrow-to-region
|
||
(point)
|
||
(save-excursion
|
||
(while (and (setq res
|
||
(re-search-forward
|
||
(if (string-match "^ONEWS\\.[0-9]+$" file)
|
||
"Changes in \\(?:Emacs\\|version\\)?[ \t]*\\([0-9]+\\(?:\\.[0-9]+\\)?\\)"
|
||
"^\* [^0-9\n]*\\([0-9]+\\.[0-9]+\\)") nil t))
|
||
(equal (match-string-no-properties 1) version)))
|
||
(or res (goto-char (point-max)))
|
||
(beginning-of-line)
|
||
(point))))))))
|
||
|
||
(defun view-todo (&optional arg)
|
||
"Display the Emacs TODO list."
|
||
(interactive "P")
|
||
(view-file (expand-file-name "TODO" data-directory)))
|
||
|
||
(defun view-echo-area-messages ()
|
||
"View the log of recent echo-area messages: the `*Messages*' buffer.
|
||
The number of messages retained in that buffer
|
||
is specified by the variable `message-log-max'."
|
||
(interactive)
|
||
(switch-to-buffer (get-buffer-create "*Messages*")))
|
||
|
||
(defun view-order-manuals ()
|
||
"Display the Emacs ORDERS file."
|
||
(interactive)
|
||
(view-file (expand-file-name "ORDERS" data-directory))
|
||
(goto-address))
|
||
|
||
(defun view-emacs-FAQ ()
|
||
"Display the Emacs Frequently Asked Questions (FAQ) file."
|
||
(interactive)
|
||
;; (find-file-read-only (expand-file-name "FAQ" data-directory))
|
||
(info "(efaq)"))
|
||
|
||
(defun view-emacs-problems ()
|
||
"Display info on known problems with Emacs and possible workarounds."
|
||
(interactive)
|
||
(view-file (expand-file-name "PROBLEMS" data-directory)))
|
||
|
||
(defun view-lossage ()
|
||
"Display last 100 input keystrokes.
|
||
|
||
To record all your input on a file, use `open-dribble-file'."
|
||
(interactive)
|
||
(help-setup-xref (list #'view-lossage) (interactive-p))
|
||
(with-output-to-temp-buffer (help-buffer)
|
||
(princ (mapconcat (lambda (key)
|
||
(if (or (integerp key) (symbolp key) (listp key))
|
||
(single-key-description key)
|
||
(prin1-to-string key nil)))
|
||
(recent-keys)
|
||
" "))
|
||
(with-current-buffer standard-output
|
||
(goto-char (point-min))
|
||
(while (progn (move-to-column 50) (not (eobp)))
|
||
(search-forward " " nil t)
|
||
(insert "\n")))
|
||
(print-help-return-message)))
|
||
|
||
|
||
;; Key bindings
|
||
|
||
(defun describe-bindings (&optional prefix buffer)
|
||
"Show a list of all defined keys, and their definitions.
|
||
We put that list in a buffer, and display the buffer.
|
||
|
||
The optional argument PREFIX, if non-nil, should be a key sequence;
|
||
then we display only bindings that start with that prefix.
|
||
The optional argument BUFFER specifies which buffer's bindings
|
||
to display (default, the current buffer). BUFFER can be a buffer
|
||
or a buffer name."
|
||
(interactive)
|
||
(or buffer (setq buffer (current-buffer)))
|
||
(help-setup-xref (list #'describe-bindings prefix buffer) (interactive-p))
|
||
(with-current-buffer buffer
|
||
(describe-bindings-internal nil prefix)))
|
||
|
||
;; This function used to be in keymap.c.
|
||
(defun describe-bindings-internal (&optional menus prefix)
|
||
"Show a list of all defined keys, and their definitions.
|
||
We put that list in a buffer, and display the buffer.
|
||
|
||
The optional argument MENUS, if non-nil, says to mention menu bindings.
|
||
\(Ordinarily these are omitted from the output.)
|
||
The optional argument PREFIX, if non-nil, should be a key sequence;
|
||
then we display only bindings that start with that prefix."
|
||
(interactive)
|
||
(let ((buf (current-buffer)))
|
||
(with-output-to-temp-buffer "*Help*"
|
||
(with-current-buffer standard-output
|
||
(describe-buffer-bindings buf prefix menus)))))
|
||
|
||
(defun where-is (definition &optional insert)
|
||
"Print message listing key sequences that invoke the command DEFINITION.
|
||
Argument is a command definition, usually a symbol with a function definition.
|
||
If INSERT (the prefix arg) is non-nil, insert the message in the buffer."
|
||
(interactive
|
||
(let ((fn (function-called-at-point))
|
||
(enable-recursive-minibuffers t)
|
||
val)
|
||
(setq val (completing-read
|
||
(if fn
|
||
(format "Where is command (default %s): " fn)
|
||
"Where is command: ")
|
||
obarray 'commandp t))
|
||
(list (if (equal val "") fn (intern val)) current-prefix-arg)))
|
||
(let ((func (indirect-function definition))
|
||
(defs nil)
|
||
(standard-output (if insert (current-buffer) t)))
|
||
(mapatoms (lambda (symbol)
|
||
(and (fboundp symbol)
|
||
(not (eq symbol definition))
|
||
(eq func (condition-case ()
|
||
(indirect-function symbol)
|
||
(error symbol)))
|
||
(push symbol defs))))
|
||
(princ (mapconcat
|
||
#'(lambda (symbol)
|
||
(let* ((remapped (command-remapping symbol))
|
||
(keys (where-is-internal
|
||
symbol overriding-local-map nil nil remapped))
|
||
(keys (mapconcat 'key-description keys ", ")))
|
||
(if insert
|
||
(if (> (length keys) 0)
|
||
(if remapped
|
||
(format "%s (%s) (remapped from %s)"
|
||
keys remapped symbol)
|
||
(format "%s (%s)" keys symbol))
|
||
(format "M-x %s RET" symbol))
|
||
(if (> (length keys) 0)
|
||
(if remapped
|
||
(format "%s is remapped to %s which is on %s"
|
||
definition symbol keys)
|
||
(format "%s is on %s" symbol keys))
|
||
(format "%s is not on any key" symbol)))))
|
||
(cons definition defs)
|
||
";\nand ")))
|
||
nil)
|
||
|
||
(defun string-key-binding (key)
|
||
"Value is the binding of KEY in a string.
|
||
If KEY is an event on a string, and that string has a `local-map'
|
||
or `keymap' property, return the binding of KEY in the string's keymap."
|
||
(let* ((defn nil)
|
||
(start (when (vectorp key)
|
||
(if (memq (aref key 0)
|
||
'(mode-line header-line left-margin right-margin))
|
||
(event-start (aref key 1))
|
||
(and (consp (aref key 0))
|
||
(event-start (aref key 0))))))
|
||
(string-info (and (consp start) (nth 4 start))))
|
||
(when string-info
|
||
(let* ((string (car string-info))
|
||
(pos (cdr string-info))
|
||
(local-map (and (>= pos 0)
|
||
(< pos (length string))
|
||
(or (get-text-property pos 'local-map string)
|
||
(get-text-property pos 'keymap string)))))
|
||
(setq defn (and local-map (lookup-key local-map key)))))
|
||
defn))
|
||
|
||
(defun help-key-description (key untranslated)
|
||
(let ((string (key-description key)))
|
||
(if (or (not untranslated)
|
||
(and (eq (aref untranslated 0) ?\e) (not (eq (aref key 0) ?\e))))
|
||
string
|
||
(let ((otherstring (key-description untranslated)))
|
||
(if (equal string otherstring)
|
||
string
|
||
(format "%s (translated from %s)" string otherstring))))))
|
||
|
||
(defun describe-key-briefly (key &optional insert untranslated)
|
||
"Print the name of the function KEY invokes. KEY is a string.
|
||
If INSERT (the prefix arg) is non-nil, insert the message in the buffer.
|
||
If non-nil UNTRANSLATED is a vector of the untranslated events.
|
||
It can also be a number in which case the untranslated events from
|
||
the last key hit are used."
|
||
(interactive "kDescribe key briefly: \nP\np")
|
||
(if (numberp untranslated)
|
||
(setq untranslated (this-single-command-raw-keys)))
|
||
(save-excursion
|
||
(let ((modifiers (event-modifiers (aref key 0)))
|
||
(standard-output (if insert (current-buffer) t))
|
||
window position)
|
||
;; For a mouse button event, go to the button it applies to
|
||
;; to get the right key bindings. And go to the right place
|
||
;; in case the keymap depends on where you clicked.
|
||
(if (or (memq 'click modifiers) (memq 'down modifiers)
|
||
(memq 'drag modifiers))
|
||
(setq window (posn-window (event-start (aref key 0)))
|
||
position (posn-point (event-start (aref key 0)))))
|
||
(if (windowp window)
|
||
(progn
|
||
(set-buffer (window-buffer window))
|
||
(goto-char position)))
|
||
;; Ok, now look up the key and name the command.
|
||
(let ((defn (or (string-key-binding key)
|
||
(key-binding key)))
|
||
(key-desc (help-key-description key untranslated)))
|
||
(if (or (null defn) (integerp defn) (equal defn 'undefined))
|
||
(princ (format "%s is undefined" key-desc))
|
||
(princ (format (if (windowp window)
|
||
"%s at that spot runs the command %s"
|
||
"%s runs the command %s")
|
||
key-desc
|
||
(if (symbolp defn) defn (prin1-to-string defn)))))))))
|
||
|
||
|
||
(defun describe-key (key &optional untranslated up-event)
|
||
"Display documentation of the function invoked by KEY.
|
||
KEY should be a key sequence--when calling from a program,
|
||
pass a string or a vector.
|
||
If non-nil UNTRANSLATED is a vector of the untranslated events.
|
||
It can also be a number in which case the untranslated events from
|
||
the last key hit are used."
|
||
(interactive "kDescribe key: \np\nU")
|
||
(if (numberp untranslated)
|
||
(setq untranslated (this-single-command-raw-keys)))
|
||
(save-excursion
|
||
(let ((modifiers (event-modifiers (aref key 0)))
|
||
window position)
|
||
;; For a mouse button event, go to the button it applies to
|
||
;; to get the right key bindings. And go to the right place
|
||
;; in case the keymap depends on where you clicked.
|
||
(if (or (memq 'click modifiers) (memq 'down modifiers)
|
||
(memq 'drag modifiers))
|
||
(setq window (posn-window (event-start (aref key 0)))
|
||
position (posn-point (event-start (aref key 0)))))
|
||
(when (windowp window)
|
||
(set-buffer (window-buffer window))
|
||
(goto-char position))
|
||
(let ((defn (or (string-key-binding key) (key-binding key))))
|
||
(if (or (null defn) (integerp defn) (equal defn 'undefined))
|
||
(message "%s is undefined" (help-key-description key untranslated))
|
||
(help-setup-xref (list #'describe-function defn) (interactive-p))
|
||
(with-output-to-temp-buffer (help-buffer)
|
||
(princ (help-key-description key untranslated))
|
||
(if (windowp window)
|
||
(princ " at that spot"))
|
||
(princ " runs the command ")
|
||
(prin1 defn)
|
||
(princ "\n which is ")
|
||
(describe-function-1 defn)
|
||
(when up-event
|
||
(let ((defn (or (string-key-binding up-event) (key-binding up-event))))
|
||
(unless (or (null defn) (integerp defn) (equal defn 'undefined))
|
||
(princ "\n\n-------------- up event ---------------\n\n")
|
||
(princ (key-description up-event))
|
||
(if (windowp window)
|
||
(princ " at that spot"))
|
||
(princ " runs the command ")
|
||
(prin1 defn)
|
||
(princ "\n which is ")
|
||
(describe-function-1 defn))))
|
||
(print-help-return-message)))))))
|
||
|
||
|
||
(defun describe-mode (&optional buffer)
|
||
"Display documentation of current major mode and minor modes.
|
||
A brief summary of the minor modes comes first, followed by the
|
||
major mode description. This is followed by detailed
|
||
descriptions of the minor modes, each on a separate page.
|
||
|
||
For this to work correctly for a minor mode, the mode's indicator
|
||
variable \(listed in `minor-mode-alist') must also be a function
|
||
whose documentation describes the minor mode."
|
||
(interactive)
|
||
(help-setup-xref (list #'describe-mode (or buffer (current-buffer)))
|
||
(interactive-p))
|
||
;; For the sake of help-do-xref and help-xref-go-back,
|
||
;; don't switch buffers before calling `help-buffer'.
|
||
(with-output-to-temp-buffer (help-buffer)
|
||
(save-excursion
|
||
(when buffer (set-buffer buffer))
|
||
(let (minor-modes)
|
||
;; Find enabled minor mode we will want to mention.
|
||
(dolist (mode minor-mode-list)
|
||
;; Document a minor mode if it is listed in minor-mode-alist,
|
||
;; non-nil, and has a function definition.
|
||
(and (boundp mode) (symbol-value mode)
|
||
(fboundp mode)
|
||
(let ((pretty-minor-mode mode)
|
||
indicator)
|
||
(if (string-match "\\(-minor\\)?-mode\\'"
|
||
(symbol-name mode))
|
||
(setq pretty-minor-mode
|
||
(capitalize
|
||
(substring (symbol-name mode)
|
||
0 (match-beginning 0)))))
|
||
(setq indicator (cadr (assq mode minor-mode-alist)))
|
||
(while (and indicator (symbolp indicator)
|
||
(boundp indicator)
|
||
(not (eq indicator (symbol-value indicator))))
|
||
(setq indicator (symbol-value indicator)))
|
||
(push (list pretty-minor-mode mode indicator)
|
||
minor-modes))))
|
||
(if auto-fill-function
|
||
;; copy pure string so we can add face property to it below.
|
||
(push (list (copy-sequence "Auto Fill") 'auto-fill-mode " Fill")
|
||
minor-modes))
|
||
(setq minor-modes
|
||
(sort minor-modes
|
||
(lambda (a b) (string-lessp (car a) (car b)))))
|
||
(when minor-modes
|
||
(princ "Summary of minor modes:\n")
|
||
(make-local-variable 'help-button-cache)
|
||
(with-current-buffer standard-output
|
||
(dolist (mode minor-modes)
|
||
(let ((pretty-minor-mode (nth 0 mode))
|
||
(mode-function (nth 1 mode))
|
||
(indicator (nth 2 mode)))
|
||
(add-text-properties 0 (length pretty-minor-mode)
|
||
'(face bold) pretty-minor-mode)
|
||
(save-excursion
|
||
(goto-char (point-max))
|
||
(princ "\n\f\n")
|
||
(push (point-marker) help-button-cache)
|
||
;; Document the minor modes fully.
|
||
(insert pretty-minor-mode)
|
||
(princ (format " minor mode (%s):\n"
|
||
(if indicator
|
||
(format "indicator%s" indicator)
|
||
"no indicator")))
|
||
(princ (documentation mode-function)))
|
||
(princ " ")
|
||
(insert-button pretty-minor-mode
|
||
'action (car help-button-cache)
|
||
'help-echo "mouse-2, RET: show full information")
|
||
(princ (format " minor mode (%s):\n"
|
||
(if indicator
|
||
(format "indicator%s" indicator)
|
||
"no indicator"))))))
|
||
(princ "\n(Full information about these minor modes
|
||
follows the description of the major mode.)\n\n"))
|
||
;; Document the major mode.
|
||
(let ((mode mode-name))
|
||
(with-current-buffer standard-output
|
||
(insert mode)
|
||
(add-text-properties (- (point) (length mode)) (point) '(face bold))))
|
||
(princ " mode:\n")
|
||
(princ (documentation major-mode)))
|
||
(print-help-return-message))))
|
||
|
||
|
||
(defun describe-minor-mode (minor-mode)
|
||
"Display documentation of a minor mode given as MINOR-MODE.
|
||
MINOR-MODE can be a minor mode symbol or a minor mode indicator string
|
||
appeared on the mode-line."
|
||
(interactive (list (completing-read
|
||
"Minor mode: "
|
||
(nconc
|
||
(describe-minor-mode-completion-table-for-symbol)
|
||
(describe-minor-mode-completion-table-for-indicator)
|
||
))))
|
||
(if (symbolp minor-mode)
|
||
(setq minor-mode (symbol-name minor-mode)))
|
||
(let ((symbols (describe-minor-mode-completion-table-for-symbol))
|
||
(indicators (describe-minor-mode-completion-table-for-indicator)))
|
||
(cond
|
||
((member minor-mode symbols)
|
||
(describe-minor-mode-from-symbol (intern minor-mode)))
|
||
((member minor-mode indicators)
|
||
(describe-minor-mode-from-indicator minor-mode))
|
||
(t
|
||
(error "No such minor mode: %s" minor-mode)))))
|
||
|
||
;; symbol
|
||
(defun describe-minor-mode-completion-table-for-symbol ()
|
||
;; In order to list up all minor modes, minor-mode-list
|
||
;; is used here instead of minor-mode-alist.
|
||
(delq nil (mapcar 'symbol-name minor-mode-list)))
|
||
(defun describe-minor-mode-from-symbol (symbol)
|
||
"Display documentation of a minor mode given as a symbol, SYMBOL"
|
||
(interactive (list (intern (completing-read
|
||
"Minor mode symbol: "
|
||
(describe-minor-mode-completion-table-for-symbol)))))
|
||
(if (fboundp symbol)
|
||
(describe-function symbol)
|
||
(describe-variable symbol)))
|
||
|
||
;; indicator
|
||
(defun describe-minor-mode-completion-table-for-indicator ()
|
||
(delq nil
|
||
(mapcar (lambda (x)
|
||
(let ((i (format-mode-line x)))
|
||
;; remove first space if existed
|
||
(cond
|
||
((= 0 (length i))
|
||
nil)
|
||
((eq (aref i 0) ?\ )
|
||
(substring i 1))
|
||
(t
|
||
i))))
|
||
minor-mode-alist)))
|
||
(defun describe-minor-mode-from-indicator (indicator)
|
||
"Display documentation of a minor mode specified by INDICATOR.
|
||
If you call this function interactively, you can give indicator which
|
||
is currently activated with completion."
|
||
(interactive (list
|
||
(completing-read
|
||
"Minor mode indicator: "
|
||
(describe-minor-mode-completion-table-for-indicator))))
|
||
(let ((minor-mode (lookup-minor-mode-from-indicator indicator)))
|
||
(if minor-mode
|
||
(describe-minor-mode-from-symbol minor-mode)
|
||
(error "Cannot find minor mode for `%s'" indicator))))
|
||
|
||
(defun lookup-minor-mode-from-indicator (indicator)
|
||
"Return a minor mode symbol from its indicator on the modeline."
|
||
;; remove first space if existed
|
||
(if (and (< 0 (length indicator))
|
||
(eq (aref indicator 0) ?\ ))
|
||
(setq indicator (substring indicator 1)))
|
||
(let ((minor-modes minor-mode-alist)
|
||
result)
|
||
(while minor-modes
|
||
(let* ((minor-mode (car (car minor-modes)))
|
||
(anindicator (format-mode-line
|
||
(car (cdr (car minor-modes))))))
|
||
;; remove first space if existed
|
||
(if (and (stringp anindicator)
|
||
(> (length anindicator) 0)
|
||
(eq (aref anindicator 0) ?\ ))
|
||
(setq anindicator (substring anindicator 1)))
|
||
(if (equal indicator anindicator)
|
||
(setq result minor-mode
|
||
minor-modes nil)
|
||
(setq minor-modes (cdr minor-modes)))))
|
||
result))
|
||
|
||
|
||
;;; Automatic resizing of temporary buffers.
|
||
|
||
(defcustom temp-buffer-max-height (lambda (buffer) (/ (- (frame-height) 2) 2))
|
||
"*Maximum height of a window displaying a temporary buffer.
|
||
This is the maximum height (in text lines) which `resize-temp-buffer-window'
|
||
will give to a window displaying a temporary buffer.
|
||
It can also be a function which will be called with the object corresponding
|
||
to the buffer to be displayed as argument and should return an integer
|
||
positive number."
|
||
:type '(choice integer function)
|
||
:group 'help
|
||
:version "20.4")
|
||
|
||
(define-minor-mode temp-buffer-resize-mode
|
||
"Toggle the mode which makes windows smaller for temporary buffers.
|
||
With prefix argument ARG, turn the resizing of windows displaying temporary
|
||
buffers on if ARG is positive or off otherwise.
|
||
This makes the window the right height for its contents, but never
|
||
more than `temp-buffer-max-height' nor less than `window-min-height'.
|
||
This applies to `help', `apropos' and `completion' buffers, and some others."
|
||
:global t :group 'help
|
||
(if temp-buffer-resize-mode
|
||
;; `help-make-xrefs' may add a `back' button and thus increase the
|
||
;; text size, so `resize-temp-buffer-window' must be run *after* it.
|
||
(add-hook 'temp-buffer-show-hook 'resize-temp-buffer-window 'append)
|
||
(remove-hook 'temp-buffer-show-hook 'resize-temp-buffer-window)))
|
||
|
||
(defun resize-temp-buffer-window ()
|
||
"Resize the current window to fit its contents.
|
||
Will not make it higher than `temp-buffer-max-height' nor smaller than
|
||
`window-min-height'. Do nothing if it is the only window on its frame, if it
|
||
is not as wide as the frame or if some of the window's contents are scrolled
|
||
out of view."
|
||
(unless (or (one-window-p 'nomini)
|
||
(not (pos-visible-in-window-p (point-min)))
|
||
(/= (frame-width) (window-width)))
|
||
(fit-window-to-buffer
|
||
(selected-window)
|
||
(if (functionp temp-buffer-max-height)
|
||
(funcall temp-buffer-max-height (current-buffer))
|
||
temp-buffer-max-height))))
|
||
|
||
;; Provide this for the sake of define-minor-mode which generates
|
||
;; defcustoms which require 'help'.
|
||
(provide 'help)
|
||
|
||
;;; arch-tag: cf427352-27e9-49b7-9a6f-741ebab02423
|
||
;;; help.el ends here
|