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help-fns+.el
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help-fns+.el
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;;; help-fns+.el --- Extensions to `help-fns.el'.
;;
;; Filename: help-fns+.el
;; Description: Extensions to `help-fns.el'.
;; Author: Drew Adams
;; Maintainer: Drew Adams (concat "drew.adams" "@" "oracle" ".com")
;; Copyright (C) 2007-2018, Drew Adams, all rights reserved.
;; Created: Sat Sep 01 11:01:42 2007
;; Version: 0
;; Package-Requires: ()
;; Last-Updated: Mon Jan 1 13:13:48 2018 (-0800)
;; By: dradams
;; Update #: 2227
;; URL: https://www.emacswiki.org/emacs/download/help-fns%2b.el
;; Doc URL: https://emacswiki.org/emacs/HelpPlus
;; Keywords: help, faces, characters, packages, description
;; Compatibility: GNU Emacs: 22.x, 23.x, 24.x, 25.x, 26.x
;;
;; Features that might be required by this library:
;;
;; `button', `cl', `help-fns', `help-mode', `naked', `view',
;; `wid-edit', `wid-edit+'.
;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;
;;; Commentary:
;;
;; Extensions to `help-fns.el'. Also includes a redefinition of
;; `describe-face', which is from `faces.el'.
;;
;; Note: As of Emacs 24.4, byte-compiling this file in one Emacs
;; version and using the compiled file in another Emacs version
;; does not work.
;;
;;
;; Keys bound here:
;;
;; `C-h B' `describe-buffer'
;; `C-h c' `describe-command' (replaces `describe-key-briefly')
;; `C-h o' `describe-option'
;; `C-h C-c' `describe-key-briefly' (replaces `C-h c')
;; `C-h C-o' `describe-option-of-type'
;; `C-h M-c' `describe-copying' (replaces `C-h C-c')
;; `C-h M-f' `describe-file'
;; `C-h M-k' `describe-keymap'
;; `C-h M-l' `find-function-on-key'
;;
;; Commands defined here:
;;
;; `describe-buffer', `describe-command', `describe-file',
;; `describe-keymap', `describe-option', `describe-option-of-type'.
;;
;; User options defined here:
;;
;; `help-cross-reference-manuals' (Emacs 23.2+).
;;
;; Faces defined here:
;;
;; `describe-variable-value' (Emacs 24+).
;;
;; Non-interactive functions defined here:
;;
;; `describe-mode-1', `help-all-exif-data',
;; `help-commands-to-key-buttons', `help-custom-type',
;; `help-documentation', `help-documentation-property' (Emacs 23+),
;; `help-key-button-string', `help-remove-duplicates',
;; `help-substitute-command-keys', `help-value-satisfies-type-p',
;; `help-var-inherits-type-p', `help-var-is-of-type-p',
;; `help-var-matches-type-p', `help-var-val-satisfies-type-p',
;; `Info-first-index-occurrence' (Emacs 23.2+),
;; `Info-indexed-find-file' (Emacs 23.2+), `Info-indexed-find-node'
;; (Emacs 23.2+), `Info-index-entries-across-manuals' (Emacs
;; 23.2+), `Info-index-occurrences' (Emacs 23.2+),
;; `Info-make-manuals-xref' (Emacs 23.2+).
;;
;; Internal variables defined here:
;;
;; `Info-indexed-file' (Emacs 23.2+), `Info-indexed-nodes' (Emacs
;; 23.2+), `variable-name-history'.
;;
;;
;; ***** NOTE: The following command defined in `faces.el'
;; has been REDEFINED HERE:
;;
;; `describe-face'.
;;
;;
;; ***** NOTE: The following command defined in `help.el'
;; has been REDEFINED HERE:
;;
;; `describe-mode'.
;;
;;
;; ***** NOTE: The following functions defined in `help-fns.el'
;; have been REDEFINED HERE:
;;
;; `describe-function', `describe-function-1', `describe-variable',
;; `help-fns--key-bindings', `help-fns--signature',
;;
;;
;; ***** NOTE: The following command defined in `package.el'
;; has been REDEFINED HERE:
;;
;; `describe-package'.
;;
;;
;; Put this in your initialization file (`~/.emacs'):
;;
;; (require 'help-fns+)
;;
;; Acknowledgement: Passing text properties on doc strings to the
;; *Help* buffer is an idea from Johan bockgard. He sent it on
;; 2007-01-24 to [email protected], Subject
;; "display-completion-list should not strip text properties".
;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;
;;; Change Log:
;;
;; 2016/09/17 dadams
;; describe-function: Fix Emacs bug #24221: let FUNCTION be anonymous.
;; 2015/12/15 dadams
;; describe-file: Remove `' around file name in title.
;; 2015/09/09 dadams
;; describe-variable: Fixed test order for non-"" VARDOC, so it does not become t.
;; 2015/09/08 dadams
;; describe-keymap: Added optional arg SEARCH-SYMBOLS-P. Follow alias chain of symbol, and describe last one.
;; describe-variable: Pick up doc from alias, if help-documentation-property returns "".
;; 2015/08/30 dadams
;; describe-function-1: Typo: auto-do-load -> autoload-do-load.
;; 2015/08/22 dadams
;; describe-keymap:
;; Allow arg to be a keymap (not a keymap variable), when not interactive. Suggestion by erjoalgo.
;; 2015/08/13 dadams
;; describe-variable:
;; PREDICATE arg to completing-read needs to use original buffer, not minibuffer, when test boundp.
;; Fixes Emacs BUG #21252.
;; 2015/08/02 dadams
;; Updated for Emacs 25
;; help-fns--signature:
;; Added arg RAW. Return DOC if FUNCTION is a keymap. Use help--make-usage-docstring.
;; Use help--docstring-quote. Insert "`X", not "(\` X)", when documenting `X. Use substitute-command-keys
;; on args to help-highlight-arguments.
;; describe-function-1:
;; Use indirect-function if subr (SIG-KEY). Moved autoloads forward). Use help-fns-short-filename.
;; Use auto-do-load. But do NOT use curly quotes - e.g., no extra substitute-command-name calls.
;; 2015/04/03 dadams
;; Use char-before in place of looking-back, for chars before. See Emacs bug #17284.
;; 2015/03/26 dadams
;; describe-package: Fix guard to use emacs-minor-version 3, not 24. Thx to Roshan Shariff.
;; 2015/03/23 dadams
;; describe-variable (Emacs 24+): Fix terpri's so appearance is better. Fill region for global value.
;; 2014/11/29 dadams
;; Info-make-manuals-xref: Control number of newlines before.
;; describe-function-1: Use same def for Emacs 25.
;; describe-variable-value: Changed the default colors.
;; describe-variable: Use face describe-variable-value always. Fill region for value always.
;; Control number of newlines before and after Value:, and after manuals xref.
;; 2014/11/12 dadams
;; describe-package:
;; Added version for Emacs 24.4+ - Use package-alist, package--builtins, or package-archive-contents.
;; 2014/11/08 dadams
;; describe-mode-1: Show major-mode and mode-function also, on a separate line (Emacs bug #18992), filling.
;; 2014/08/10 dadams
;; describe-command: Bind completion-annotate-function for use with Icicles.
;; 2014/05/11 dadams
;; help-substitute-command-keys: Bug: \= was not being removed - C-h f replace-regexp showed \=\N, not \N.
;; Small loop for \=: changed \\\\=$ to \\\\=.
;; Main loop, when escaped (\=) and odd: Skip the \=: concat before \= with after \=.
;; 2014/05/04 dadams
;; Use called-interactively only for Emacs 23.2+, since we pass it an arg.
;; 2014/05/02 dadams
;; describe-package: Updated for Emacs 24.4 - defstruct package-desc.
;; 2014/04/21 dadams
;; with-selected-frame: Updated for Emacs 24.4.
;; describe-face: Updated for Emacs 24.4: Try face-at-point for read-face-name default.
;; describe-file, describe-keymap, describe-function:
;; Updated for Emacs 24.4: Use with-help-window, not with-output-to-temp-buffer. See bug #17109.
;; describe-function-1: Created version for Emacs 24.4+
;; help-key-button-string: Do not quote :type.
;; describe-buffer, describe-mode-1, describe-function: Use called-interactively, if available.
;; Removed autoload cookie for describe-function, describe-keymap (but why?).
;; 2014/03/06 dadams
;; describe-variable: Fixed typo in regexp: [n] -> [\n].
;; 2014/01/04 dadams
;; Added: describe-variable-value.
;; describe-variable (Emacs 24+): Highlight the value with face describe-variable-value.
;; 2013/08/06 dadams
;; describe-function: Ensure arg is a defined function before calling describe-function-1 (for Emacs 24+).
;; 2013/07/01 dadams
;; Revert the filling part of yesterday's update.
;; 2013/06/30 dadams
;; describe-variable for Emacs 24+:
;; Update for vanilla Emacs 24.4. Update for Emacs bug #14754: fill printed value so no long lines.
;; 2013/06/16 dadams
;; describe-(variable|option(-of-type)): Fixed for dumb variable-at-point, which returns 0 for no var.
;; 2013/04/29 dadams
;; describe-(function|command|variable|option|option-of-type):
;; Provide default only if symbol is of the right type. Put default in prompt.
;; 2013/02/08 dadams
;; describe-variable: Updated wrt Emacs 24 build of 2013-01-30.
;; 2012/11/18 dadams
;; describe-(variable|function): Add completion-candidate annotation: (option|command).
;; 2012/10/28 dadams
;; help-fns--key-bindings: Fixed: forgot to mapconcat over keys.
;; 2012/10/26 dadams
;; Added: help-fns--key-bindings, help-fns--signature,
;; Added Emacs 24.3+ version of describe-function-1. Updated version for 23.2-24.2.
;; help-substitute-command-keys: Fix for \= when no match for \[, \<, \{ past it.
;; 2012/09/24 dadams
;; describe-file: Added optional arg NO-ERROR-P.
;; 2012/09/22 dadams
;; Info-index-occurrences, Info-first-index-occurrence:
;; Replace Info-directory call by short version. Better Searching msg.
;; 2012/09/21 dadams
;; Renamed Info-any-index-occurrences-p to Info-first-index-occurrence.
;; Info-any-index-occurrences-p: Return the first successful lookup, not t.
;; Info-index-entries-across-manuals, Info-index-occurrences, Info-any-index-occurrences-p:
;; Added optional arg INDEX-NODES.
;; Adjust calls to those fns accordingly, e.g., in define-button-type for help-info-manual-lookup
;; and help-insert-xref-button in Info-make-manuals-xref.
;; 2012/07/20 dadams
;; Added: describe-buffer, describe-mode-1. Bound describe-buffer to C-h B.
;; describe-mode: Redefined to use describe-mode-1.
;; 2012/07/03 dadams
;; Info-make-manuals-xref, Info-index-entries-across-manuals, Info-index-occurrences,
;; Info-any-index-occurrences-p:
;; Added optional arg NOMSG.
;; describe-(function|variable|file|package): No message if not interactive-p.
;; describe-function-1: pass MSGP to Info-make-manuals-xref (i.e. msg always).
;; describe-(mode|variable|face|keymap|package): Pass proper NOMSG arg to Info-make-manuals-xref.
;; 2012/01/11 dadams
;; describe-variable: Remove * from beginning of doc string.
;; 2011/11/25 dadams
;; Reverted yesterday's change and added IMPORTANT note to Commentary.
;; 2011/11/24 dadams
;; Added Emacs 24 version of with-help-window. They changed the signature of help-window-setup.
;; 2011/10/14 dadams
;; describe-mode: Call help-documentation while in mode's buffer, in case no \\<...>.
;; 2011/10/08 dadams
;; Info-make-manuals-xref: Do nothing if OBJECT is not a string or a symbol (e.g. is a keymap).
;; 2011/10/07 dadams
;; Added soft require of naked.el.
;; help-substitute-command-keys, describe-function-1: Use naked-key-description if available.
;; 2011/08/22 dadams
;; describe-variable (Emacs 23+): Added terpri after Value: (for multiline value).
;; 2011/07/25 dadams
;; describe-mode:
;; Put call to help-documentation inside let for maj: else major-mode gets changed to help-mode.
;; 2011/06/26 dadams
;; Added: help-commands-to-key-buttons, help-documentation(-property),
;; help-key-button-string, help-substitute-command-keys (Emacs 23+).
;; describe-(mode|variable|function-1|keymap) for Emacs 23+:
;; Use help-documentation (with insert and button arg), instead of documentation (with princ).
;; 2011/06/22 dadams
;; Info-make-manuals-xref: Added optional arg MANUALS.
;; 2011/06/20 dadams
;; Info(-any)-index-occurrences(-p): Fix pattern: remove arbitrary prefix [^\n]*.
;; Added, for Emacs 24+: describe-package.
;; 2011/06/14 dadams
;; Added, for Emacs 23.2+: describe-mode.
;; Info-make-manuals-xref: Added optional arg NO-NEWLINES-AFTER-P.
;; 2011/06/13 dadams
;; Added: Info-any-index-occurrences-p.
;; Info-make-manuals-xref: Use Info-any-index-occurrences-p, not Info-index-occurrences.
;; 2011/06/11 dadams
;; Added, for Emacs 23.2+:
;; describe-face, describe-function-1, help-cross-reference-manuals, Info-indexed-find-file,
;; Info-indexed-find-node, Info-index-entries-across-manuals, Info-index-occurrences,
;; Info-make-manuals-xref, Info-indexed-file, Info-indexed-nodes.
;; describe-keymap: Emacs 23.2+: Added link to manuals.
;; describe-variable: Updated Emacs 23 version, per vanilla.
;; Emacs 23.2+: Added link to manuals.
;; Require info.el for Emacs 23.2+.
;; 2011/04/25 dadams
;; describe-file: Incorporate autofile bookmark description. Added optional arg.
;; 2011/03/31 dadams
;; help-var-(matches|inherits)-type-p: Wrap string-match with save-match-data.
;; 2011/03/17 dadams
;; describe-file: Added clickable thumbnail image to the help for an image file.
;; 2011/03/02 dadams
;; Added: help-all-exif-data
;; describe-file: Show all EXIF data, using help-all-exif-data.
;; 2011/02/22 dadams
;; describe-file: Show also EXIF data for an image file.
;; 2011/01/04 dadams
;; Removed autoload cookies from non def* sexps and define-key.
;; 2010/02/12 dadams
;; Added variable-name-history.
;; 2009/08/30 dadams
;; describe-keymap: Don't print nil if the map has no doc.
;; 2009/05/26 dadams
;; describe-variable: Updated wrt latest Emacs 23:
;; Added file-name-non-directory; removed substitute-command-keys.
;; 2008/09/13 dadams
;; Updated for latest Emacs 23 CVS.
;; describe-variable: Create separate version for Emacs 23.
;; describe-function-1: No longer needed for Emacs 23, since my patch added.
;; Added: with-selected-frame, with-help-window, at least temporarily.
;; Require wid-edit.el.
;; 2008/09/02 dadams
;; describe-function-1, describe-variable:
;; Emacs 23 uses find-lisp-object-file-name. Thx to Per Nordlow.
;; 2008/08/19 dadams
;; describe-keymap: Use insert instead of princ for map part. Thx to Chong Yidong.
;; 2008/05/20 dadams
;; describe-function: Different prompt if prefix arg.
;; 2008/03/02 dadams
;; Moved describe-file here from misc-cmds.el. Bound to C-h M-f.
;; Require cl.el at compile time.
;; 2008/02/01 dadams
;; Bound M-l to find-function-on-key.
;; 2008/01/03 dadams
;; Added: describe-function-1. The redefinition fills overlong lines.
;; 2007/12/25 dadams
;; help-var-inherits-type-p:
;; Recheck var-type match after set var-type to its car.
;; Handle string (regexp) TYPES elements.
;; help-value-satisfies-type-p: Skip type check for string type (regexp).
;; help-var-is-of-type-p: Doc string. Use help-var-matches-type-p.
;; Added: help-var-matches-type-p.
;; 2007/12/24 dadams
;; help-var-inherits-type-p: Recheck type match after set var-type to its car.
;; Added: help-custom-type.
;; 2007/12/23 dadams
;; help-var-is-of-type-p:
;; Added MODE arg. Use help-var-inherits-type-p, help-var-val-satisfies-type-p.
;; Redefined as MODE choice, not just a simple or. Treat more cases.
;; Added: help-var-inherits-type-p, help-var-val-satisfies-type-p,
;; help-value-satisfies-type-p.
;; describe-option-of-type: Prefix arg means use mode inherit-or-value.
;; 2007/12/22 dadams
;; help-var-is-of-type-p:
;; Check supertypes also. Use both :validate and :match.
;; Wrap type check in condition-case. Use widget-put instead of plist-put.
;; Added soft require of wid-edit+.el.
;; 2007/12/21 dadams
;; help-var-is-of-type-p: Use :validate, not :match, for the test.
;; 2007/12/20 dadams
;; Moved describe-option-of-type to C-h C-o.
;; 2007/12/15 dadams
;; Bound C-h c to describe-command and C-h C-c to describe-key-briefly.
;; 2007/12/07 dadams
;; describe-option-of-type:
;; Call describe-variable with nil buffer. Use "nil" as default value.
;; 2007/12/06 dadams
;; describe-option-of-type:
;; If nil type, all defcustom vars are candidates. Use custom-variable-p.
;; Specific error if no such custom type.
;; 2007/12/04 dadams
;; Added: describe-option-of-type, help-remove-duplicates, help-var-is-of-type-p.
;; Bound o to describe-option, M-o to describe-option-of-type,
;; C-c to describe-command, M-c to describe-copying.
;; 2007/11/28 dadams
;; Renamed describe-bindings-in-map to describe-keymap. Added keymap's doc string.
;; 2007/11/22 dadams
;; Added: describe-bindings-in-map. Bound to C-h M-k.
;; 2007/11/01 dadams
;; Corrected require typo: help-mode -> help-fns.
;; 2007/10/18 dadams
;; Created.
;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;
;; 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 2, 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; see the file COPYING. If not, write to
;; the Free Software Foundation, Inc., 51 Franklin Street, Fifth
;; Floor, Boston, MA 02110-1301, USA.
;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;
;;; Code:
(require 'help-fns)
(require 'wid-edit+ nil t) ;; (no error if not found):
;; redefined color widget (for help-var-is-of-type-p)
(require 'wid-edit) ;; widget-convert
(require 'naked nil t) ;; (no error if not found): naked-key-description
(when (or (> emacs-major-version 23) (and (= emacs-major-version 23) (> emacs-minor-version 1)))
(require 'info)) ;; Info-virtual-files
;; [2022-05-27 Fri] comment out. It looks like the cl- version of case is used,
;; and I replaced gentemp with cl-gentemp.
;; (eval-when-compile (require 'cl))
;; case, gentemp
;; Quiet the byte-compiler.
(defvar advertised-signature-table)
(defvar dir-local-variables-alist)
(defvar dir-locals-file)
(defvar file-local-variables-alist)
(defvar icicle-mode) ; In `icicles-mode.el'
(defvar icicle-pre-minibuffer-buffer) ; In `icicles-var.el'
(defvar Info-indexed-nodes) ; In `info.el'
(defvar help-cross-reference-manuals) ; For Emacs < 23.2
(defvar help-enable-auto-load) ; For Emacs < 24.3
(defvar package-alist)
(defvar package-archive-contents)
(defvar package--builtins)
(defvar package--initialized)
;;;;;;;;;;;;;;;;;;;;;;;;
(defvar variable-name-history () "Minibuffer history for variable names.")
(define-key help-map "B" 'describe-buffer)
(define-key help-map "c" 'describe-command)
(define-key help-map "o" 'describe-option)
(define-key help-map "\C-c" 'describe-key-briefly)
(define-key help-map "\C-o" 'describe-option-of-type)
(define-key help-map "\M-c" 'describe-copying)
(define-key help-map "\M-f" 'describe-file)
(define-key help-map "\M-k" 'describe-keymap)
(define-key help-map "\M-l" 'find-function-on-key)
;; Need Emacs 23 for version of `make-text-button' that accepts a string.
(when (> emacs-major-version 22)
(defun help-documentation (function &optional raw add-help-buttons)
"Same as `documentation', but optionally adds buttons for help.
Non-nil optional arg ADD-HELP-BUTTONS does that, adding buttons to key
descriptions, which link to the key's command help."
(let ((raw-doc (documentation function 'RAW)))
(if raw raw-doc (help-substitute-command-keys raw-doc add-help-buttons))))
(defun help-documentation-property (symbol prop &optional raw add-help-buttons)
"Same as `documentation-property', but optionally adds buttons for help.
Non-nil optional arg ADD-HELP-BUTTONS does that, adding buttons to key
descriptions, which link to the key's command help."
(let ((raw-doc (documentation-property symbol prop 'RAW)))
(if raw raw-doc (help-substitute-command-keys raw-doc add-help-buttons))))
(defun help-commands-to-key-buttons (string)
"Like `substitute-command-keys', but adds buttons for help on keys.
Key descriptions become links to help about their commands."
(help-substitute-command-keys string 'ADD-HELP-BUTTONS))
(defun help-substitute-command-keys (string &optional add-help-buttons)
"Same as `substitute-command-keys', but optionally adds buttons for help.
Non-nil optional arg ADD-HELP-BUTTONS does that, adding buttons to key
descriptions, which link to the key's command help."
;; REPEAT:
;; Search for first occurrence of any of the patterns: \[...], \{...}, or \<...>.
;; Handle escaping via \=, if present before the pattern or if there is no pattern match.
;; If pattern is a keymap (\<...>): use it from then on.
;; If pattern is a command (\[...]): (a) substitute its key description, (b) put a button on it.
;; If pattern is a bindings spec (\{...}): just substitute the usual text.
(with-syntax-table emacs-lisp-mode-syntax-table
(let* ((strg (copy-sequence string))
(len-strg (length strg))
(ii 0)
(jj 0)
(newstrg "")
(re-command "\\\\\\[\\(\\(\\sw\\|\\s_\\)+\\)\\]")
(re-keymap "\\\\<\\(\\(\\sw\\|\\s_\\)+\\)>")
(re-bindings "\\\\{\\(\\(\\sw\\|\\s_\\)+\\)}")
(re-any (concat "\\(" re-command "\\|" re-keymap "\\|" re-bindings "\\)"))
(keymap (or overriding-terminal-local-map overriding-local-map))
(msg nil)
key bindings ma mc mk mb)
(while (< ii len-strg)
(setq key nil
bindings ()
strg (substring strg ii))
(save-match-data ; ANY
(setq ma (string-match re-any strg))
(cond ((not ma) ; No \[...], \{...}, or \<...>, but we need to handle \=
(setq jj 0
newstrg (concat newstrg (replace-regexp-in-string
"\\\\=\\(.\\)" "\\1" strg nil nil nil jj)))
(when (match-beginning 1) (setq jj (match-beginning 1)))
(setq ii len-strg))
(t
(let ((escaped nil)
(odd nil))
(save-match-data
(let ((ma/= ma))
(setq ii ma)
(while (string-match "\\\\=" (substring strg 0 ma/=))
(setq odd (not odd)
ma/= (match-beginning 0))
(when odd (setq ii (- ii 2)
escaped ma/=)))))
(if (not escaped)
(setq ii ma
jj (match-end 0)
ma (match-string-no-properties 0 strg)
newstrg (concat newstrg (substring strg 0 ii)))
(setq jj (match-end 0) ; End of \[...], \{...}, or \<...>
ma (and (not odd) (match-string-no-properties 0 strg))
newstrg (if odd
(concat newstrg
(substring strg 0 escaped) ; Before \='s
(substring strg (+ 2 escaped) ii)) ; After \='s
(concat newstrg (substring strg 0 ii)))))))))
(when ma
(save-match-data ; KEYMAP
(setq ma (copy-sequence ma))
(setq mk (string-match re-keymap ma))
(setq mk (and mk (match-string-no-properties 0 ma)))
(when mk
(setq keymap (intern (match-string-no-properties 1 ma)))
(if (boundp keymap)
(setq keymap (symbol-value keymap))
(setq msg (format "\nUses keymap \"%s\", which is not currently defined.\n" keymap))
(setq keymap (or overriding-terminal-local-map overriding-local-map)))))
(unless mk ; COMMAND
(save-match-data
(setq ma (copy-sequence ma))
(setq mc (string-match re-command ma))
(setq mc (and mc (match-string-no-properties 0 ma)))
(setq mc (and mc (intern (substring mc 2 -1)))) ; Remove \[...] envelope
(when mc
(let ((follow-remap t))
(while (and (setq key (where-is-internal mc keymap 'FIRSTONLY))
(vectorp key) (> (length key) 1) (eq 'remap (aref key 0))
(symbolp (aref key 1)) follow-remap)
(setq mc (aref key 1)
follow-remap nil)))
(setq key (if key
(if (fboundp 'naked-key-description)
(naked-key-description key)
(key-description key))
(concat "M-x " (symbol-name mc))))
(when add-help-buttons (setq key (help-key-button-string key mc))))))
(unless (or mk mc) ; BINDINGS
(save-match-data
(setq ma (copy-sequence ma))
(setq mb (string-match re-bindings ma))
(setq mb (and mb (match-string-no-properties 0 ma)))
(when mb
(setq bindings (intern (match-string-no-properties 1 ma)))
(cond ((boundp bindings)
(setq bindings (substitute-command-keys mb))) ; Use original - no buttons.
(t
(setq msg (format "\nUses keymap \"%s\", which is not currently defined.\n"
bindings))
(setq bindings nil))))))
(unless mk (setq newstrg (concat newstrg (or key bindings (substring strg ii jj)))))
(setq ii (or jj len-strg))))
(if (string= string newstrg)
string ; Return original string, not a copy, if no changes.
newstrg))))
(defun help-key-button-string (key-description command)
"Return a button for KEY-DESCRIPTION that links to the COMMAND description.
KEY-DESCRIPTION is a key-description string.
COMMAND is the command (a symbol) associated with the key described.
Return a copy of string KEY-DESCRIPTION with button properties added.
Clicking the button shows the help for COMMAND."
(let ((new-key (copy-sequence key-description)))
(make-text-button new-key nil 'button (list t) :type 'help-function 'help-args (list command))
new-key)))
(when (boundp 'Info-virtual-files) ; Emacs 23.2+
(defcustom help-cross-reference-manuals '(("emacs" "elisp"))
"*Manuals to search, for a `*Help*' buffer link to the manuals.
A cons.
The car is a list of manuals to search, or the symbol `all', to
search all. If nil, then do not create a cross-reference link.
The cdr is a boolean:
Non-`nil' means search the manuals, then create a cross-ref link:
create it only if some search hits are found.
`nil' means create a cross-ref link without searching manuals
first (but only if there are some manuals to search)."
:set #'(lambda (sym defs) (custom-set-default sym defs) (setq Info-indexed-nodes ()))
:type '(cons
(choice :tag "Which Manuals"
(repeat :tag "Specific Manuals (files)" string)
(const :tag "All Manuals" all))
(boolean :tag "Search Before Creating Button?"))
:group 'help)
(defvar Info-indexed-file "*Indexed*"
"Info file for virtual manual from `Info-index-entries-across-manuals'.")
(defvar Info-indexed-nodes ()
"Alist of cached nodes with matching index entries.
Each element is (NODENAME STRING MATCHES), where:
NODENAME is the name of the node that is indexed,
STRING is the search string passed to `Info-index-occurrences',
MATCHES is a list of index matches found by `Info-index-occurrences'.
This has the same structure as `Info-apropos-nodes', but the search
was made by `Info-index-occurrences', not by `Info-apropos-matches',
so that matches are exact (ignoring case).")
(defun Info-indexed-find-file (filename &optional _noerror)
"Index-search implementation of `Info-find-file'."
filename)
(defun Info-indexed-find-node (_filename nodename &optional _no-going-back)
"Index-search implementation of `Info-find-node-2'."
(let* ((nodeinfo (assoc nodename Info-indexed-nodes))
(matches (nth 2 nodeinfo)))
(when matches
(insert (format "\n\^_\nFile: %s, Node: %s, Up: Top\n\n" Info-indexed-file nodename))
(insert "Index Matches\n")
(insert "*************\n\n")
(insert "Index entries that match `" (nth 1 nodeinfo) "':\n\n")
(insert "\0\b[index\0\b]\n")
(if (eq matches t)
(insert "No matches found.\n")
(insert "* Menu:\n\n")
(dolist (entry matches)
(insert (format "* %-38s (%s)%s.%s\n" (format "%s [%s]:" (nth 1 entry) (nth 0 entry))
(nth 0 entry) (nth 2 entry)
(if (nth 3 entry) (format " (line %s)" (nth 3 entry)) ""))))))))
(add-to-list 'Info-virtual-files '("\\`\\*Indexed\\*\\'"
(find-file . Info-indexed-find-file)
(find-node . Info-indexed-find-node)
;; (slow . t) ; $$$$$$ Useless here?
))
(defun Info-make-manuals-xref (object &optional no-newlines-after-p manuals-spec nomsg)
"Create a cross-ref link for index entries for OBJECT in manuals.
Non-`nil' optional arg NO-NEWLINES-AFTER-P means do not add two
newlines after the cross reference.
Optional arg MANUALS-SPEC controls which manuals to search. It has
the same form as option `help-cross-reference-manuals', and it
defaults to the value of that option.
Do nothing if the car of MANUALS-SPEC is nil (no manuals to search).
If its cdr is `nil' then create the link without first searching any
manuals. Otherwise, create the link only if there are search hits in
the manuals."
(when (or (stringp object) (symbolp object)) ; Exclude, e.g., a keymap as OBJECT.
(unless manuals-spec (setq manuals-spec help-cross-reference-manuals))
(when (car manuals-spec) ; Create no link if no manuals to search.
(let ((books (car manuals-spec))
(search-now-p (cdr manuals-spec))
(symb-name (if (stringp object) object (symbol-name object))))
(when (or (not search-now-p)
(save-current-buffer (Info-first-index-occurrence symb-name () books nomsg)))
(let ((buffer-read-only nil)
(nl-before (cond ((and (eq ?\n (char-before)) ; Quicker than `looking-back', apparently.
(eq ?\n (char-before (1- (point))))) "")
((eq ?\n (char-before)) "\n")
(t "\n\n"))))
(insert (format "%sFor more information %s the " nl-before (if (cdr manuals-spec) "see" "check")))
(help-insert-xref-button "manuals" 'help-info-manual-lookup symb-name () books)
(insert ".")
(unless no-newlines-after-p (insert "\n\n"))))))))
(when (and (> emacs-major-version 21)
(condition-case nil (require 'help-mode nil t) (error nil))
(get 'help-xref 'button-category-symbol)) ; In `button.el'
(define-button-type 'help-info-manual-lookup
:supertype 'help-xref
'help-function #'(lambda (string &optional index-nodes books nomsg)
(Info-index-entries-across-manuals string () books nomsg))
'help-echo "mouse-2, RET: Look it up in the manuals"))
(defun Info-index-entries-across-manuals (string &optional index-nodes manuals nomsg)
"Look up STRING in Info MANUALS on your system.
Looks for exact matches (ignoring case): STRING is expected to be an
index entry. Build an Info menu of the possible matches.
Optional arg INDEX-NODES are the index nodes in MANUALS to search.
By default (nil value), all indexes are searched.
Optional arg MANUALS is the list of manuals to search, or the symbol
`all', to search all.
Optional arg NOMSG non-nil means do not display a progress message."
(let ((nodes Info-indexed-nodes)
nodename)
(while (and nodes (not (equal string (nth 1 (car nodes))))) (setq nodes (cdr nodes)))
(if nodes
(Info-find-node Info-indexed-file (car (car nodes)))
(setq nodename (format "Index for `%s'" string))
(push (list nodename string (Info-index-occurrences string index-nodes manuals nomsg))
Info-indexed-nodes)
(Info-find-node Info-indexed-file nodename))))
;; Similar to `Info-apropos-matches', but using exact matches (ignoring case).
(defun Info-index-occurrences (index-entry &optional index-nodes manuals nomsg)
"Collect occurrences of INDEX-ENTRY in INDEX-NODES of MANUALS.
Return a list of the form ((FILE INDEX-ENTRY NODE LINE) ...), where:
FILE is the name of an Info file,
NODE is an Info node name,
LINE is the line number of the INDEX-ENTRY occurrence in that node.
Optional arg INDEX-NODES are the index nodes in MANUALS to search.
By default (nil value), search all indexes of each manual.
Optional arg MANUALS is the list of manuals to search, or the symbol
`all', to search all.
Optional arg NOMSG non-nil means do not display a progress message."
(unless (string= index-entry "")
;; Unlike `Info-apropos-matches', we match only the exact string as an index entry.
(let ((pattern (format "\n\\* +\\(%s\\):[ \t]+\\([^\n]+\\)\
\\.\\(?:[ \t\n]*(line +\\([0-9]+\\))\\)?"
(regexp-quote index-entry)))
matches node)
(unless nomsg
(message "Searching indexes of %s..."
(cond ((eq manuals 'all) "all manuals")
((null (cadr manuals)) (concat (car manuals) " manual"))
(t (concat "manuals " (mapconcat #'identity manuals ", "))))))
(condition-case nil
(with-temp-buffer
(when (eq manuals 'all) (setq manuals ()))
(Info-mode)
;; Next two lines are essentially `(Info-directory)'.
(info-initialize)
(Info-find-node-2 "dir" "top" 'NO-GOING-BACK)
(unless manuals
(goto-char (point-min))
(re-search-forward "\\* Menu: *\n" nil t)
(let (manual)
(while (re-search-forward "\\*.*: *(\\([^)]+\\))" nil t)
;; `add-to-list' ensures no dups in `manuals', so the `dolist' runs faster.
(setq manual (match-string 1))
(set-text-properties 0 (length manual) nil manual)
(add-to-list 'manuals manual))))
(dolist (manual manuals)
(unless nomsg (message "Searching indexes of manual `%s'..." manual))
(when (or index-nodes
(setq index-nodes (Info-index-nodes (Info-find-file manual))))
(Info-find-node manual (car index-nodes))
(while (progn (goto-char (point-min))
(while (re-search-forward pattern nil t)
(setq matches (cons (list manual
(match-string-no-properties 1)
(match-string-no-properties 2)
(match-string-no-properties 3))
matches)))
(setq index-nodes (cdr index-nodes)
node (car index-nodes)))
(Info-goto-node node)))))
(error nil))
matches)))
;; Like `Info-index-occurrences', but return only the first occurrence found.
(defun Info-first-index-occurrence (index-entry &optional index-nodes manuals nomsg)
"Return nil or an occurrence of INDEX-ENTRY in INDEX-NODES of MANUALS.
Search INDEX-NODES and MANUALS in order.
A non-nil return value is the first first successful index lookup, in
the form (FILE INDEX-ENTRY NODE LINE) - see `Info-index-occurrences'.
Optional arg INDEX-NODES are the index nodes of MANUALS to search.
By default (nil value), search all indexes of each manual.
Optional arg MANUALS is the list of manuals to search, or the symbol
`all', to search all.
Optional arg NOMSG non-nil means do not display a progress message."
(and (not (string= index-entry ""))
;; Unlike `Info-apropos-matches', we match only the exact string as an index entry.
(let ((pattern (format "\n\\* +\\(%s\\):[ \t]+\\([^\n]+\\)\
\\.\\(?:[ \t\n]*(line +\\([0-9]+\\))\\)?"
(regexp-quote index-entry)))
(found nil)
node)
(unless nomsg
(message "Searching indexes of %s..."
(cond ((eq manuals 'all) "all manuals")
((null (cadr manuals)) (concat (car manuals) " manual"))
(t (concat "manuals " (mapconcat #'identity manuals ", "))))))
(condition-case nil
(with-temp-buffer
(when (eq manuals 'all) (setq manuals ()))
(Info-mode)
;; Next two lines are essentially `(Info-directory)'.
(info-initialize)
(Info-find-node-2 "dir" "top" 'NO-GOING-BACK)
(unless manuals
(goto-char (point-min))
(re-search-forward "\\* Menu: *\n" nil t)
(let (manual)
(while (re-search-forward "\\*.*: *(\\([^)]+\\))" nil t)
;; `add-to-list' ensures no dups in `manuals', so the `dolist' runs faster.
(setq manual (match-string 1))
(set-text-properties 0 (length manual) nil manual)
(add-to-list 'manuals manual))))
(setq found (catch 'Info-first-index-occurrence
(dolist (manual manuals)
(unless nomsg
(message "Searching indexes of manual `%s'..." manual))
(when (or index-nodes
(setq index-nodes (Info-index-nodes
(Info-find-file manual))))
(Info-find-node manual (car index-nodes))
(while (progn (goto-char (point-min))
(when (re-search-forward pattern nil t)
(throw 'Info-first-index-occurrence
(list manual
(match-string-no-properties 1)
(match-string-no-properties 2)
(match-string-no-properties 3))))
(setq index-nodes (cdr index-nodes)
node (car index-nodes)))
(Info-goto-node node))))
nil)))
(error nil))
found)))
(defun describe-buffer (&optional buffer-name) ; Bound to `C-h B'
"Describe the existing buffer named BUFFER-NAME.
The description includes the information provided by `describe-mode'.
By default, describe the current buffer."
;; (interactive "bDescribe buffer: ")
(interactive "@")
(unless buffer-name (setq buffer-name (buffer-name)))
(help-setup-xref `(describe-buffer ,buffer-name) (called-interactively-p 'interactive))
(let ((buf (get-buffer buffer-name)))
(unless (and buf (buffer-live-p buf)) (error(format "No such live buffer `%s'" buffer-name)))
(let* ((file (or (buffer-file-name buf)
(with-current-buffer buf
(and (eq major-mode 'dired-mode) default-directory))))
(help-text (concat
(format "Buffer `%s'\n%s\n\n" buffer-name (make-string
(+ 9 (length buffer-name)) ?-))
(and file (format "File/directory:\t%s\n" file))
(format "Mode:\t\t%s\n"
(with-current-buffer buf (format-mode-line mode-name)))
(format "Size in chars:\t%g\n" (buffer-size buf))
(with-current-buffer buf
(if (not buffer-display-time)
"Never displayed\n"
(format "Last displayed:\t%s\n"
(format-time-string
;; Could use this, for short format: "%02H:%02M:%02S"
;; Or this, for a bit longer: "%_3a %_2l:%02M:%02S %_2p"
"%a %b %e %T %Y (%z)"
buffer-display-time))))
(format "Modified:\t%s\n" (if (buffer-modified-p buf) "yes" "no"))
(with-current-buffer buf
(format "Read-only:\t%s\n\n\n" (if buffer-read-only "yes" "no"))))))
(with-help-window (help-buffer)
(describe-mode-1 buf))
(with-current-buffer (help-buffer)
(let ((inhibit-read-only t))
(goto-char (point-min))
(insert help-text))))))
;; REPLACE ORIGINAL
;;
;; Use `describe-mode-1', which is different from the original `describe-mode' in these ways:
;;
;; 1. Call `Info-make-manuals-xref' to create a cross-ref link to manuals.
;; 2. Add key-description buttons to command help. Use `insert', not `princ'.
;;
(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 "@")
(unless buffer (setq buffer (current-buffer)))
(help-setup-xref (list #'describe-mode buffer) (called-interactively-p 'interactive))
(with-help-window (help-buffer) (describe-mode-1 buffer))
nil) ; For the sake of IELM and maybe others
(defun describe-mode-1 (buffer)
"Helper for `describe-mode'.
Does everything except create the help window and set up the
back/forward buttons, so you can use this in other help commands that
have their own back/forward buttons."
;; For the sake of `help-do-xref' and `help-xref-go-back', do not switch buffers before calling `help-buffer'.
(with-current-buffer buffer
(let (minor-modes)
;; Older packages do not register in minor-mode-list but only in `minor-mode-alist'.
(dolist (x minor-mode-alist)
(setq x (car x))
(unless (memq x minor-mode-list) (push x minor-mode-list)))
(dolist (mode minor-mode-list) ; Find enabled minor mode we will want to mention.
;; Document minor mode if listed in `minor-mode-alist', non-nil, and has a function def.
(let ((fmode (or (get mode :minor-mode-function) mode)))
(and (boundp mode) (symbol-value mode) (fboundp fmode)
(let ((pretty-minor-mode (if (string-match "\\(\\(-minor\\)?-mode\\)?\\'"
(symbol-name fmode))
(capitalize (substring (symbol-name fmode)
0 (match-beginning 0)))
fmode)))
(push (list fmode pretty-minor-mode
(format-mode-line (assq mode minor-mode-alist)))
minor-modes)))))
(setq minor-modes (sort minor-modes (lambda (a b) (string-lessp (cadr a) (cadr b)))))
(when minor-modes
(princ "Enabled minor modes:\n")
(make-local-variable 'help-button-cache)
(with-current-buffer standard-output
(dolist (mode minor-modes)
(let ((mode-function (nth 0 mode))
(pretty-minor-mode (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:\n(`%s'; %s)\n" mode-function (if (zerop (length indicator))
"no indicator"
(format "indicator%s" indicator))))
(save-excursion
(fill-region-as-paragraph (line-beginning-position 0) (line-end-position 0) nil t t))
(with-current-buffer standard-output
(insert (help-documentation mode-function nil 'ADD-HELP-BUTTONS)))
(Info-make-manuals-xref mode-function
t nil (not (called-interactively-p 'interactive)))) ; Link manuals.
(insert-button pretty-minor-mode 'action (car help-button-cache)
'follow-link t 'help-echo "mouse-2, RET: show full information")
(newline)))
(forward-line -1)
(fill-paragraph nil)
(forward-line 1))
(princ "\n(Information about these minor modes follows the major mode info.)\n\n"))
(let ((mode mode-name)) ; Document the major mode.
(with-current-buffer standard-output
(let ((start (point)))
(insert (format-mode-line mode nil nil buffer))
(add-text-properties start (point) '(face bold)))))
(princ " mode")
(let* ((mode major-mode)
(file-name (find-lisp-object-file-name mode nil)))
(when file-name
(princ (concat " defined in `" (file-name-nondirectory file-name) "'"))
(with-current-buffer standard-output ; Make a hyperlink to the library.
(save-excursion (re-search-backward "`\\([^`']+\\)'" nil t)
(help-xref-button 1 'help-function-def mode file-name))))
(with-current-buffer standard-output
(insert (format " (`%s'):\n" mode))
(save-excursion
(fill-region-as-paragraph (line-beginning-position 0) (line-end-position 0) nil t t))))
(let* ((maj major-mode)
(maj-doc (help-documentation maj nil 'ADD-HELP-BUTTONS)))
(with-current-buffer standard-output
(insert maj-doc)
(Info-make-manuals-xref
maj t nil (not (called-interactively-p 'interactive)))))))) ; Link to manuals.
)
;; REPLACE ORIGINAL in `help-fns.el':
;;
;; 1. Preferred candidate is `symbol-nearest-point'.
;; 2. With a prefix argument, candidates are commands only.
;; 3. No no-function message if not called interactively.
;; 4. Works for anonymous functions too: lambda forms and byte-compiled functions. (Fixes Emacs bug #24221.)
;;
(defun describe-function (function &optional commandp)
"Display the full documentation of FUNCTION (a symbol).
FUNCTION names an Emacs Lisp function, possibly a user command.
With a prefix argument, candidates are only commands (interactive).
Default candidate is: preferably the `symbol-nearest-point', or else
the innermost function call surrounding point
\(`function-called-at-point').
Return the description that was displayed, as a string."
(interactive
(let* ((fn (or (and (fboundp 'symbol-nearest-point) (symbol-nearest-point))
(function-called-at-point)))
(enable-recursive-minibuffers t)
(completion-annotate-function (lambda (fn) (and (commandp (intern-soft fn)) " (command)")))
(type (if current-prefix-arg 'command 'function))
(prompt (format "Describe %s%s: " type
(if (if current-prefix-arg (commandp fn) (fboundp fn))
(format " (default %s)" fn)
"")))
val)
(setq val (completing-read prompt obarray (if current-prefix-arg 'commandp 'fboundp) t nil nil
(and (if current-prefix-arg (commandp fn) (fboundp fn)) (symbol-name fn))))
(list (if (equal val "") fn (intern val)) current-prefix-arg)))
(let* ((interactivep (if (or (> emacs-major-version 23) ; Emacs 23.1 `called-interactively' accepts no arg.
(and (= emacs-major-version 23) (> emacs-minor-version 1)))
(called-interactively-p 'interactive)