diff options
author | Martin Rudalics <[email protected]> | 2008-09-08 06:36:51 +0000 |
---|---|---|
committer | Martin Rudalics <[email protected]> | 2008-09-08 06:36:51 +0000 |
commit | ed66e2353981e427c49b487cfa1a1912dcae0154 (patch) | |
tree | e537c3290deb7cf4f79dda4f8377a97f037ddc49 /lisp/help-fns.el | |
parent | 187bc86f15320f5680552b8bd692a62fb1a4b3ba (diff) |
(find-lisp-object-file-name): Handle case where
library is compressed.
Diffstat (limited to 'lisp/help-fns.el')
-rw-r--r-- | lisp/help-fns.el | 1588 |
1 files changed, 795 insertions, 793 deletions
diff --git a/lisp/help-fns.el b/lisp/help-fns.el index 7d7e9efe33..30ead87151 100644 --- a/lisp/help-fns.el +++ b/lisp/help-fns.el @@ -1,793 +1,795 @@ -;;; help-fns.el --- Complex help functions - -;; Copyright (C) 1985, 1986, 1993, 1994, 1998, 1999, 2000, 2001, -;; 2002, 2003, 2004, 2005, 2006, 2007, 2008 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 3 of the License, 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. If not, see <http://www.gnu.org/licenses/>. - -;;; Commentary: - -;; This file contains those help commands which are complicated, and -;; which may not be used in every session. For example -;; `describe-function' will probably be heavily used when doing elisp -;; programming, but not if just editing C files. Simpler help commands -;; are in help.el - -;;; Code: - -(require 'help-mode) - -;; Functions - -;;;###autoload -(defun describe-function (function) - "Display the full documentation of FUNCTION (a symbol)." - (interactive - (let ((fn (function-called-at-point)) - (enable-recursive-minibuffers t) - val) - (setq val (completing-read (if fn - (format "Describe function (default %s): " fn) - "Describe function: ") - obarray 'fboundp t nil nil - (and fn (symbol-name fn)))) - (list (if (equal val "") - fn (intern val))))) - (if (null function) - (message "You didn't specify a function") - (help-setup-xref (list #'describe-function function) (interactive-p)) - (save-excursion - (with-help-window (help-buffer) - (prin1 function) - ;; Use " is " instead of a colon so that - ;; it is easier to get out the function name using forward-sexp. - (princ " is ") - (describe-function-1 function) - (with-current-buffer standard-output - ;; Return the text we displayed. - (buffer-string)))))) - -(defun help-split-fundoc (docstring def) - "Split a function DOCSTRING into the actual doc and the usage info. -Return (USAGE . DOC) or nil if there's no usage info. -DEF is the function whose usage we're looking for in DOCSTRING." - ;; Functions can get the calling sequence at the end of the doc string. - ;; In cases where `function' has been fset to a subr we can't search for - ;; function's name in the doc string so we use `fn' as the anonymous - ;; function name instead. - (when (and docstring (string-match "\n\n(fn\\(\\( .*\\)?)\\)\\'" docstring)) - (cons (format "(%s%s" - ;; Replace `fn' with the actual function name. - (if (consp def) "anonymous" def) - (match-string 1 docstring)) - (substring docstring 0 (match-beginning 0))))) - -(defun help-add-fundoc-usage (docstring arglist) - "Add the usage info to DOCSTRING. -If DOCSTRING already has a usage info, then just return it unchanged. -The usage info is built from ARGLIST. DOCSTRING can be nil. -ARGLIST can also be t or a string of the form \"(FUN ARG1 ARG2 ...)\"." - (unless (stringp docstring) (setq docstring "Not documented")) - (if (or (string-match "\n\n(fn\\(\\( .*\\)?)\\)\\'" docstring) (eq arglist t)) - docstring - (concat docstring - (if (string-match "\n?\n\\'" docstring) - (if (< (- (match-end 0) (match-beginning 0)) 2) "\n" "") - "\n\n") - (if (and (stringp arglist) - (string-match "\\`([^ ]+\\(.*\\))\\'" arglist)) - (concat "(fn" (match-string 1 arglist) ")") - (format "%S" (help-make-usage 'fn arglist)))))) - -(defun help-function-arglist (def) - ;; Handle symbols aliased to other symbols. - (if (and (symbolp def) (fboundp def)) (setq def (indirect-function def))) - ;; If definition is a macro, find the function inside it. - (if (eq (car-safe def) 'macro) (setq def (cdr def))) - (cond - ((byte-code-function-p def) (aref def 0)) - ((eq (car-safe def) 'lambda) (nth 1 def)) - ((and (eq (car-safe def) 'autoload) (not (eq (nth 4 def) 'keymap))) - "[Arg list not available until function definition is loaded.]") - (t t))) - -(defun help-make-usage (function arglist) - (cons (if (symbolp function) function 'anonymous) - (mapcar (lambda (arg) - (if (not (symbolp arg)) - (if (and (consp arg) (symbolp (car arg))) - ;; CL style default values for optional args. - (cons (intern (upcase (symbol-name (car arg)))) - (cdr arg)) - arg) - (let ((name (symbol-name arg))) - (if (string-match "\\`&" name) arg - (intern (upcase name)))))) - arglist))) - -;; Could be this, if we make symbol-file do the work below. -;; (defun help-C-file-name (subr-or-var kind) -;; "Return the name of the C file where SUBR-OR-VAR is defined. -;; KIND should be `var' for a variable or `subr' for a subroutine." -;; (symbol-file (if (symbolp subr-or-var) subr-or-var -;; (subr-name subr-or-var)) -;; (if (eq kind 'var) 'defvar 'defun))) -;;;###autoload -(defun help-C-file-name (subr-or-var kind) - "Return the name of the C file where SUBR-OR-VAR is defined. -KIND should be `var' for a variable or `subr' for a subroutine." - (let ((docbuf (get-buffer-create " *DOC*")) - (name (if (eq 'var kind) - (concat "V" (symbol-name subr-or-var)) - (concat "F" (subr-name subr-or-var))))) - (with-current-buffer docbuf - (goto-char (point-min)) - (if (eobp) - (insert-file-contents-literally - (expand-file-name internal-doc-file-name doc-directory))) - (let ((file (catch 'loop - (while t - (let ((pnt (search-forward (concat "" name "\n")))) - (re-search-backward "S\\(.*\\)") - (let ((file (match-string 1))) - (if (member file build-files) - (throw 'loop file) - (goto-char pnt)))))))) - (if (string-match "^ns.*\\(\\.o\\|obj\\)\\'" file) - (setq file (replace-match ".m" t t file 1)) - (if (string-match "\\.\\(o\\|obj\\)\\'" file) - (setq file (replace-match ".c" t t file)))) - (if (string-match "\\.\\(c\\|m\\)\\'" file) - (concat "src/" file) - file))))) - -(defface help-argument-name '((((supports :slant italic)) :inherit italic)) - "Face to highlight argument names in *Help* buffers." - :group 'help) - -(defun help-default-arg-highlight (arg) - "Default function to highlight arguments in *Help* buffers. -It returns ARG in face `help-argument-name'; ARG is also -downcased if it displays differently than the default -face (according to `face-differs-from-default-p')." - (propertize (if (face-differs-from-default-p 'help-argument-name) - (downcase arg) - arg) - 'face 'help-argument-name)) - -(defun help-do-arg-highlight (doc args) - (with-syntax-table (make-syntax-table emacs-lisp-mode-syntax-table) - (modify-syntax-entry ?\- "w") - (dolist (arg args doc) - (setq doc (replace-regexp-in-string - ;; This is heuristic, but covers all common cases - ;; except ARG1-ARG2 - (concat "\\<" ; beginning of word - "\\(?:[a-z-]*-\\)?" ; for xxx-ARG - "\\(" - (regexp-quote arg) - "\\)" - "\\(?:es\\|s\\|th\\)?" ; for ARGth, ARGs - "\\(?:-[a-z0-9-]+\\)?" ; for ARG-xxx, ARG-n - "\\(?:-[{([<`\"].*?\\)?"; for ARG-{x}, (x), <x>, [x], `x' - "\\>") ; end of word - (help-default-arg-highlight arg) - doc t t 1))))) - -(defun help-highlight-arguments (usage doc &rest args) - (when usage - (with-temp-buffer - (insert usage) - (goto-char (point-min)) - (let ((case-fold-search nil) - (next (not (or args (looking-at "\\[")))) - (opt nil)) - ;; Make a list of all arguments - (skip-chars-forward "^ ") - (while next - (or opt (not (looking-at " &")) (setq opt t)) - (if (not (re-search-forward " \\([\\[(]*\\)\\([^] &)\.]+\\)" nil t)) - (setq next nil) - (setq args (cons (match-string 2) args)) - (when (and opt (string= (match-string 1) "(")) - ;; A pesky CL-style optional argument with default value, - ;; so let's skip over it - (search-backward "(") - (goto-char (scan-sexps (point) 1))))) - ;; Highlight aguments in the USAGE string - (setq usage (help-do-arg-highlight (buffer-string) args)) - ;; Highlight arguments in the DOC string - (setq doc (and doc (help-do-arg-highlight doc args)))))) - ;; Return value is like the one from help-split-fundoc, but highlighted - (cons usage doc)) - -;; The following function was compiled from the former functions -;; `describe-simplify-lib-file-name' and `find-source-lisp-file' with -;; some excerpts from `describe-function-1' and `describe-variable'. -;; The only additional twists provided are (1) locate the defining file -;; for autoloaded functions, and (2) give preference to files in the -;; "install directory" (directories found via `load-path') rather than -;; to files in the "compile directory" (directories found by searching -;; the loaddefs.el file). We autoload it because it's also used by -;; `describe-face' (instead of `describe-simplify-lib-file-name'). - -;;;###autoload -(defun find-lisp-object-file-name (object type) - "Guess the file that defined the Lisp object OBJECT, of type TYPE. -OBJECT should be a symbol associated with a function, variable, or face; - alternatively, it can be a function definition. -If TYPE is `variable', search for a variable definition. -If TYPE is `face', search for a face definition. -If TYPE is the value returned by `symbol-function' for a function symbol, - search for a function definition. - -The return value is the absolute name of a readable file where OBJECT is -defined. If several such files exist, preference is given to a file -found via `load-path'. The return value can also be `C-source', which -means that OBJECT is a function or variable defined in C. If no -suitable file is found, return nil." - (let* ((autoloaded (eq (car-safe type) 'autoload)) - (file-name (or (and autoloaded (nth 1 type)) - (symbol-file - object (if (memq type (list 'defvar 'defface)) - type - 'defun))))) - (cond - (autoloaded - ;; An autoloaded function: Locate the file since `symbol-function' - ;; has only returned a bare string here. - (setq file-name - (locate-file file-name load-path '(".el" ".elc") 'readable))) - ((and (stringp file-name) - (string-match "[.]*loaddefs.el\\'" file-name)) - ;; An autoloaded variable or face. Visit loaddefs.el in a buffer - ;; and try to extract the defining file. The following form is - ;; from `describe-function-1' and `describe-variable'. - (let ((location - (condition-case nil - (find-function-search-for-symbol object nil file-name) - (error nil)))) - (when location - (with-current-buffer (car location) - (goto-char (cdr location)) - (when (re-search-backward - "^;;; Generated autoloads from \\(.*\\)" nil t) - (setq file-name - (locate-file - (match-string-no-properties 1) - load-path nil 'readable)))))))) - - (cond - ((and (not file-name) (subrp type)) - ;; A built-in function. The form is from `describe-function-1'. - (if (get-buffer " *DOC*") - (help-C-file-name type 'subr) - 'C-source)) - ((and (not file-name) (symbolp object) - (integerp (get object 'variable-documentation))) - ;; A variable defined in C. The form is from `describe-variable'. - (if (get-buffer " *DOC*") - (help-C-file-name object 'var) - 'C-source)) - ((not (stringp file-name)) - ;; If we don't have a file-name string by now, we lost. - nil) - ((let ((lib-name - (if (string-match "[.]elc\\'" file-name) - (substring-no-properties file-name 0 -1) - file-name))) - ;; When the Elisp source file can be found in the install - ;; directory return the name of that file - `file-name' should - ;; have become an absolute file name ny now. - (and (file-readable-p lib-name) lib-name))) - ((let* ((lib-name (file-name-nondirectory file-name)) - ;; The next form is from `describe-simplify-lib-file-name'. - (file-name - ;; Try converting the absolute file name to a library - ;; name, convert that back to a file name and see if we - ;; get the original one. If so, they are equivalent. - (if (equal file-name (locate-file lib-name load-path '(""))) - (if (string-match "[.]elc\\'" lib-name) - (substring-no-properties lib-name 0 -1) - lib-name) - file-name)) - ;; The next three forms are from `find-source-lisp-file'. - (elc-file (locate-file - (concat file-name - (if (string-match "\\.el\\'" file-name) - "c" - ".elc")) - load-path nil 'readable)) - (str (when elc-file - (with-temp-buffer - (insert-file-contents-literally elc-file nil 0 256) - (buffer-string)))) - (src-file (and str - (string-match ";;; from file \\(.*\\.el\\)" str) - (match-string 1 str)))) - (and src-file (file-readable-p src-file) src-file)))))) - -(declare-function ad-get-advice-info "advice" (function)) - -;;;###autoload -(defun describe-function-1 (function) - (let* ((advised (and (symbolp function) (featurep 'advice) - (ad-get-advice-info function))) - ;; If the function is advised, use the symbol that has the - ;; real definition, if that symbol is already set up. - (real-function - (or (and advised - (let ((origname (cdr (assq 'origname advised)))) - (and (fboundp origname) origname))) - function)) - ;; Get the real definition. - (def (if (symbolp real-function) - (symbol-function real-function) - function)) - file-name string - (beg (if (commandp def) "an interactive " "a ")) - (pt1 (with-current-buffer (help-buffer) (point))) - errtype) - (setq string - (cond ((or (stringp def) - (vectorp def)) - "a keyboard macro") - ((subrp def) - (if (eq 'unevalled (cdr (subr-arity def))) - (concat beg "special form") - (concat beg "built-in function"))) - ((byte-code-function-p def) - (concat beg "compiled Lisp function")) - ((symbolp def) - (while (and (fboundp def) - (symbolp (symbol-function def))) - (setq def (symbol-function def))) - ;; Handle (defalias 'foo 'bar), where bar is undefined. - (or (fboundp def) (setq errtype 'alias)) - (format "an alias for `%s'" def)) - ((eq (car-safe def) 'lambda) - (concat beg "Lisp function")) - ((eq (car-safe def) 'macro) - "a Lisp macro") - ((eq (car-safe def) 'autoload) - (format "%s autoloaded %s" - (if (commandp def) "an interactive" "an") - (if (eq (nth 4 def) 'keymap) "keymap" - (if (nth 4 def) "Lisp macro" "Lisp function")))) - ((keymapp def) - (let ((is-full nil) - (elts (cdr-safe def))) - (while elts - (if (char-table-p (car-safe elts)) - (setq is-full t - elts nil)) - (setq elts (cdr-safe elts))) - (if is-full - "a full keymap" - "a sparse keymap"))) - (t ""))) - (princ string) - (if (eq errtype 'alias) - (princ ",\nwhich is not defined. Please make a bug report.") - (with-current-buffer standard-output - (save-excursion - (save-match-data - (when (re-search-backward "alias for `\\([^`']+\\)'" nil t) - (help-xref-button 1 'help-function def))))) - - (setq file-name (find-lisp-object-file-name function def)) - (when file-name - (princ " in `") - ;; We used to add .el to the file name, - ;; but that's completely wrong when the user used load-file. - (princ (if (eq file-name 'C-source) "C source code" file-name)) - (princ "'") - ;; Make a hyperlink to the library. - (with-current-buffer standard-output - (save-excursion - (re-search-backward "`\\([^`']+\\)'" nil t) - (help-xref-button 1 'help-function-def real-function file-name)))) - (princ ".") - (with-current-buffer (help-buffer) - (fill-region-as-paragraph (save-excursion (goto-char pt1) (forward-line 0) (point)) - (point))) - (terpri)(terpri) - (when (commandp function) - (let ((pt2 (with-current-buffer (help-buffer) (point)))) - (if (and (eq function 'self-insert-command) - (eq (key-binding "a") 'self-insert-command) - (eq (key-binding "b") 'self-insert-command) - (eq (key-binding "c") 'self-insert-command)) - (princ "It is bound to many ordinary text characters.\n") - (let* ((remapped (command-remapping function)) - (keys (where-is-internal - (or remapped function) overriding-local-map nil nil)) - non-modified-keys) - ;; Which non-control non-meta keys run this command? - (dolist (key keys) - (if (member (event-modifiers (aref key 0)) '(nil (shift))) - (push key non-modified-keys))) - (when remapped - (princ "It is remapped to `") - (princ (symbol-name remapped)) - (princ "'")) - - (when keys - (princ (if remapped ", which is bound to " "It is bound to ")) - ;; If lots of ordinary text characters run this command, - ;; don't mention them one by one. - (if (< (length non-modified-keys) 10) - (princ (mapconcat 'key-description keys ", ")) - (dolist (key non-modified-keys) - (setq keys (delq key keys))) - (if keys - (progn - (princ (mapconcat 'key-description keys ", ")) - (princ ", and many ordinary text characters")) - (princ "many ordinary text characters")))) - (when (or remapped keys non-modified-keys) - (princ ".") - (terpri)))) - (with-current-buffer (help-buffer) (fill-region-as-paragraph pt2 (point))) - (terpri))) - (let* ((arglist (help-function-arglist def)) - (doc (documentation function)) - (usage (help-split-fundoc doc function))) - (with-current-buffer standard-output - ;; If definition is a keymap, skip arglist note. - (unless (keymapp function) - (let* ((use (cond - (usage (setq doc (cdr usage)) (car usage)) - ((listp arglist) - (format "%S" (help-make-usage function arglist))) - ((stringp arglist) arglist) - ;; Maybe the arglist is in the docstring of a symbol - ;; this one is aliased to. - ((let ((fun real-function)) - (while (and (symbolp fun) - (setq fun (symbol-function fun)) - (not (setq usage (help-split-fundoc - (documentation fun) - function))))) - usage) - (car usage)) - ((or (stringp def) - (vectorp def)) - (format "\nMacro: %s" (format-kbd-macro def))) - (t "[Missing arglist. Please make a bug report.]"))) - (high (help-highlight-arguments use doc))) - (let ((fill-begin (point))) - (insert (car high) "\n") - (fill-region fill-begin (point))) - (setq doc (cdr high)))) - (let* ((obsolete (and - ;; function might be a lambda construct. - (symbolp function) - (get function 'byte-obsolete-info))) - (use (car obsolete))) - (when obsolete - (princ "\nThis function is obsolete") - (when (nth 2 obsolete) - (insert (format " since %s" (nth 2 obsolete)))) - (insert (cond ((stringp use) (concat ";\n" use)) - (use (format ";\nuse `%s' instead." use)) - (t ".")) - "\n")) - (insert "\n" - (or doc "Not documented.")))))))) - - -;; Variables - -;;;###autoload -(defun variable-at-point (&optional any-symbol) - "Return the bound variable symbol found at or before point. -Return 0 if there is no such symbol. -If ANY-SYMBOL is non-nil, don't insist the symbol be bound." - (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) (boundp obj) obj))) - (error nil)) - (let* ((str (find-tag-default)) - (sym (if str (intern-soft str)))) - (if (and sym (or any-symbol (boundp sym))) - sym - (save-match-data - (when (and str (string-match "\\`\\W*\\(.*?\\)\\W*\\'" str)) - (setq sym (intern-soft (match-string 1 str))) - (and (or any-symbol (boundp sym)) sym))))) - 0))) - -(defun describe-variable-custom-version-info (variable) - (let ((custom-version (get variable 'custom-version)) - (cpv (get variable 'custom-package-version)) - (output nil)) - (if custom-version - (setq output - (format "This variable was introduced, or its default value was changed, in\nversion %s of Emacs.\n" - custom-version)) - (when cpv - (let* ((package (car-safe cpv)) - (version (if (listp (cdr-safe cpv)) - (car (cdr-safe cpv)) - (cdr-safe cpv))) - (pkg-versions (assq package customize-package-emacs-version-alist)) - (emacsv (cdr (assoc version pkg-versions)))) - (if (and package version) - (setq output - (format (concat "This variable was introduced, or its default value was changed, in\nversion %s of the %s package" - (if emacsv - (format " that is part of Emacs %s" emacsv)) - ".\n") - version package)))))) - output)) - -;;;###autoload -(defun describe-variable (variable &optional buffer frame) - "Display the full documentation of VARIABLE (a symbol). -Returns the documentation as a string, also. -If VARIABLE has a buffer-local value in BUFFER or FRAME -\(default to the current buffer and current frame), -it is displayed along with the global value." - (interactive - (let ((v (variable-at-point)) - (enable-recursive-minibuffers t) - val) - (setq val (completing-read (if (symbolp v) - (format - "Describe variable (default %s): " v) - "Describe variable: ") - obarray - '(lambda (vv) - (or (boundp vv) - (get vv 'variable-documentation))) - t nil nil - (if (symbolp v) (symbol-name v)))) - (list (if (equal val "") - v (intern val))))) - (let (file-name) - (unless (buffer-live-p buffer) (setq buffer (current-buffer))) - (unless (frame-live-p frame) (setq frame (selected-frame))) - (if (not (symbolp variable)) - (message "You did not specify a variable") - (save-excursion - (let ((valvoid (not (with-current-buffer buffer (boundp variable)))) - val val-start-pos locus) - ;; Extract the value before setting up the output buffer, - ;; in case `buffer' *is* the output buffer. - (unless valvoid - (with-selected-frame frame - (with-current-buffer buffer - (setq val (symbol-value variable) - locus (variable-binding-locus variable))))) - (help-setup-xref (list #'describe-variable variable buffer) - (interactive-p)) - (with-help-window (help-buffer) - (with-current-buffer buffer - (prin1 variable) - (setq file-name (find-lisp-object-file-name variable 'defvar)) - - (if file-name - (progn - (princ " is a variable defined in `") - (princ (if (eq file-name 'C-source) "C source code" file-name)) - (princ "'.\n") - (with-current-buffer standard-output - (save-excursion - (re-search-backward "`\\([^`']+\\)'" nil t) - (help-xref-button 1 'help-variable-def - variable file-name))) - (if valvoid - (princ "It is void as a variable.") - (princ "Its "))) - (if valvoid - (princ " is void as a variable.") - (princ "'s ")))) - (if valvoid - nil - (with-current-buffer standard-output - (setq val-start-pos (point)) - (princ "value is ") - (terpri) - (let ((from (point))) - (pp val) - ;; Hyperlinks in variable's value are quite frequently - ;; inappropriate e.g C-h v <RET> features <RET> - ;; (help-xref-on-pp from (point)) - (if (< (point) (+ from 20)) - (delete-region (1- from) from))))) - (terpri) - - (when locus - (if (bufferp locus) - (princ (format "%socal in buffer %s; " - (if (get variable 'permanent-local) - "Permanently l" "L") - (buffer-name))) - (princ (format "It is a frame-local variable; "))) - (if (not (default-boundp variable)) - (princ "globally void") - (let ((val (default-value variable))) - (with-current-buffer standard-output - (princ "global value is ") - (terpri) - ;; Fixme: pp can take an age if you happen to - ;; ask for a very large expression. We should - ;; probably print it raw once and check it's a - ;; sensible size before prettyprinting. -- fx - (let ((from (point))) - (pp val) - ;; See previous comment for this function. - ;; (help-xref-on-pp from (point)) - (if (< (point) (+ from 20)) - (delete-region (1- from) from)))))) - (terpri)) - - ;; If the value is large, move it to the end. - (with-current-buffer standard-output - (when (> (count-lines (point-min) (point-max)) 10) - ;; Note that setting the syntax table like below - ;; makes forward-sexp move over a `'s' at the end - ;; of a symbol. - (set-syntax-table emacs-lisp-mode-syntax-table) - (goto-char val-start-pos) - ;; The line below previously read as - ;; (delete-region (point) (progn (end-of-line) (point))) - ;; which suppressed display of the buffer local value for - ;; large values. - (when (looking-at "value is") (replace-match "")) - (save-excursion - (insert "\n\nValue:") - (set (make-local-variable 'help-button-cache) - (point-marker))) - (insert "value is shown ") - (insert-button "below" - 'action help-button-cache - 'follow-link t - 'help-echo "mouse-2, RET: show value") - (insert ".\n"))) - (terpri) - - (let* ((alias (condition-case nil - (indirect-variable variable) - (error variable))) - (obsolete (get variable 'byte-obsolete-variable)) - (use (car obsolete)) - (safe-var (get variable 'safe-local-variable)) - (doc (or (documentation-property variable 'variable-documentation) - (documentation-property alias 'variable-documentation))) - (extra-line nil)) - ;; Add a note for variables that have been make-var-buffer-local. - (when (and (local-variable-if-set-p variable) - (or (not (local-variable-p variable)) - (with-temp-buffer - (local-variable-if-set-p variable)))) - (setq extra-line t) - (princ " Automatically becomes buffer-local when set in any fashion.\n")) - - ;; Mention if it's an alias - (unless (eq alias variable) - (setq extra-line t) - (princ (format " This variable is an alias for `%s'.\n" alias))) - - (when obsolete - (setq extra-line t) - (princ " This variable is obsolete") - (if (cdr obsolete) (princ (format " since %s" (cdr obsolete)))) - (princ (cond ((stringp use) (concat ";\n " use)) - (use (format ";\n use `%s' instead." (car obsolete))) - (t "."))) - (terpri)) - (when safe-var - (setq extra-line t) - (princ " This variable is safe as a file local variable ") - (princ "if its value\n satisfies the predicate ") - (princ (if (byte-code-function-p safe-var) - "which is byte-compiled expression.\n" - (format "`%s'.\n" safe-var)))) - - (if extra-line (terpri)) - (princ "Documentation:\n") - (with-current-buffer standard-output - (insert (or doc "Not documented as a variable.")))) - - ;; Make a link to customize if this variable can be customized. - (when (custom-variable-p variable) - (let ((customize-label "customize")) - (terpri) - (terpri) - (princ (concat "You can " customize-label " this variable.")) - (with-current-buffer standard-output - (save-excursion - (re-search-backward - (concat "\\(" customize-label "\\)") nil t) - (help-xref-button 1 'help-customize-variable variable)))) - ;; Note variable's version or package version - (let ((output (describe-variable-custom-version-info variable))) - (when output - (terpri) - (terpri) - (princ output)))) - - (save-excursion - (set-buffer standard-output) - ;; Return the text we displayed. - (buffer-string)))))))) - - -;;;###autoload -(defun describe-syntax (&optional buffer) - "Describe the syntax specifications in the syntax table of BUFFER. -The descriptions are inserted in a help buffer, which is then displayed. -BUFFER defaults to the current buffer." - (interactive) - (setq buffer (or buffer (current-buffer))) - (help-setup-xref (list #'describe-syntax buffer) (interactive-p)) - (with-help-window (help-buffer) - (let ((table (with-current-buffer buffer (syntax-table)))) - (with-current-buffer standard-output - (describe-vector table 'internal-describe-syntax-value) - (while (setq table (char-table-parent table)) - (insert "\nThe parent syntax table is:") - (describe-vector table 'internal-describe-syntax-value)))))) - -(defun help-describe-category-set (value) - (insert (cond - ((null value) "default") - ((char-table-p value) "deeper char-table ...") - (t (condition-case err - (category-set-mnemonics value) - (error "invalid")))))) - -;;;###autoload -(defun describe-categories (&optional buffer) - "Describe the category specifications in the current category table. -The descriptions are inserted in a buffer, which is then displayed. -If BUFFER is non-nil, then describe BUFFER's category table instead. -BUFFER should be a buffer or a buffer name." - (interactive) - (setq buffer (or buffer (current-buffer))) - (help-setup-xref (list #'describe-categories buffer) (interactive-p)) - (with-help-window (help-buffer) - (let ((table (with-current-buffer buffer (category-table)))) - (with-current-buffer standard-output - (describe-vector table 'help-describe-category-set) - (let ((docs (char-table-extra-slot table 0))) - (if (or (not (vectorp docs)) (/= (length docs) 95)) - (insert "Invalid first extra slot in this char table\n") - (insert "Meanings of mnemonic characters are:\n") - (dotimes (i 95) - (let ((elt (aref docs i))) - (when elt - (insert (+ i ?\s) ": " elt "\n")))) - (while (setq table (char-table-parent table)) - (insert "\nThe parent category table is:") - (describe-vector table 'help-describe-category-set)))))))) - -(provide 'help-fns) - -;; arch-tag: 9e10331c-ae81-4d13-965d-c4819aaab0b3 -;;; help-fns.el ends here +;;; help-fns.el --- Complex help functions
+
+;; Copyright (C) 1985, 1986, 1993, 1994, 1998, 1999, 2000, 2001,
+;; 2002, 2003, 2004, 2005, 2006, 2007, 2008 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 3 of the License, 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. If not, see <http://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; This file contains those help commands which are complicated, and
+;; which may not be used in every session. For example
+;; `describe-function' will probably be heavily used when doing elisp
+;; programming, but not if just editing C files. Simpler help commands
+;; are in help.el
+
+;;; Code:
+
+(require 'help-mode)
+
+;; Functions
+
+;;;###autoload
+(defun describe-function (function)
+ "Display the full documentation of FUNCTION (a symbol)."
+ (interactive
+ (let ((fn (function-called-at-point))
+ (enable-recursive-minibuffers t)
+ val)
+ (setq val (completing-read (if fn
+ (format "Describe function (default %s): " fn)
+ "Describe function: ")
+ obarray 'fboundp t nil nil
+ (and fn (symbol-name fn))))
+ (list (if (equal val "")
+ fn (intern val)))))
+ (if (null function)
+ (message "You didn't specify a function")
+ (help-setup-xref (list #'describe-function function) (interactive-p))
+ (save-excursion
+ (with-help-window (help-buffer)
+ (prin1 function)
+ ;; Use " is " instead of a colon so that
+ ;; it is easier to get out the function name using forward-sexp.
+ (princ " is ")
+ (describe-function-1 function)
+ (with-current-buffer standard-output
+ ;; Return the text we displayed.
+ (buffer-string))))))
+
+(defun help-split-fundoc (docstring def)
+ "Split a function DOCSTRING into the actual doc and the usage info.
+Return (USAGE . DOC) or nil if there's no usage info.
+DEF is the function whose usage we're looking for in DOCSTRING."
+ ;; Functions can get the calling sequence at the end of the doc string.
+ ;; In cases where `function' has been fset to a subr we can't search for
+ ;; function's name in the doc string so we use `fn' as the anonymous
+ ;; function name instead.
+ (when (and docstring (string-match "\n\n(fn\\(\\( .*\\)?)\\)\\'" docstring))
+ (cons (format "(%s%s"
+ ;; Replace `fn' with the actual function name.
+ (if (consp def) "anonymous" def)
+ (match-string 1 docstring))
+ (substring docstring 0 (match-beginning 0)))))
+
+(defun help-add-fundoc-usage (docstring arglist)
+ "Add the usage info to DOCSTRING.
+If DOCSTRING already has a usage info, then just return it unchanged.
+The usage info is built from ARGLIST. DOCSTRING can be nil.
+ARGLIST can also be t or a string of the form \"(FUN ARG1 ARG2 ...)\"."
+ (unless (stringp docstring) (setq docstring "Not documented"))
+ (if (or (string-match "\n\n(fn\\(\\( .*\\)?)\\)\\'" docstring) (eq arglist t))
+ docstring
+ (concat docstring
+ (if (string-match "\n?\n\\'" docstring)
+ (if (< (- (match-end 0) (match-beginning 0)) 2) "\n" "")
+ "\n\n")
+ (if (and (stringp arglist)
+ (string-match "\\`([^ ]+\\(.*\\))\\'" arglist))
+ (concat "(fn" (match-string 1 arglist) ")")
+ (format "%S" (help-make-usage 'fn arglist))))))
+
+(defun help-function-arglist (def)
+ ;; Handle symbols aliased to other symbols.
+ (if (and (symbolp def) (fboundp def)) (setq def (indirect-function def)))
+ ;; If definition is a macro, find the function inside it.
+ (if (eq (car-safe def) 'macro) (setq def (cdr def)))
+ (cond
+ ((byte-code-function-p def) (aref def 0))
+ ((eq (car-safe def) 'lambda) (nth 1 def))
+ ((and (eq (car-safe def) 'autoload) (not (eq (nth 4 def) 'keymap)))
+ "[Arg list not available until function definition is loaded.]")
+ (t t)))
+
+(defun help-make-usage (function arglist)
+ (cons (if (symbolp function) function 'anonymous)
+ (mapcar (lambda (arg)
+ (if (not (symbolp arg))
+ (if (and (consp arg) (symbolp (car arg)))
+ ;; CL style default values for optional args.
+ (cons (intern (upcase (symbol-name (car arg))))
+ (cdr arg))
+ arg)
+ (let ((name (symbol-name arg)))
+ (if (string-match "\\`&" name) arg
+ (intern (upcase name))))))
+ arglist)))
+
+;; Could be this, if we make symbol-file do the work below.
+;; (defun help-C-file-name (subr-or-var kind)
+;; "Return the name of the C file where SUBR-OR-VAR is defined.
+;; KIND should be `var' for a variable or `subr' for a subroutine."
+;; (symbol-file (if (symbolp subr-or-var) subr-or-var
+;; (subr-name subr-or-var))
+;; (if (eq kind 'var) 'defvar 'defun)))
+;;;###autoload
+(defun help-C-file-name (subr-or-var kind)
+ "Return the name of the C file where SUBR-OR-VAR is defined.
+KIND should be `var' for a variable or `subr' for a subroutine."
+ (let ((docbuf (get-buffer-create " *DOC*"))
+ (name (if (eq 'var kind)
+ (concat "V" (symbol-name subr-or-var))
+ (concat "F" (subr-name subr-or-var)))))
+ (with-current-buffer docbuf
+ (goto-char (point-min))
+ (if (eobp)
+ (insert-file-contents-literally
+ (expand-file-name internal-doc-file-name doc-directory)))
+ (let ((file (catch 'loop
+ (while t
+ (let ((pnt (search-forward (concat "" name "\n"))))
+ (re-search-backward "S\\(.*\\)")
+ (let ((file (match-string 1)))
+ (if (member file build-files)
+ (throw 'loop file)
+ (goto-char pnt))))))))
+ (if (string-match "^ns.*\\(\\.o\\|obj\\)\\'" file)
+ (setq file (replace-match ".m" t t file 1))
+ (if (string-match "\\.\\(o\\|obj\\)\\'" file)
+ (setq file (replace-match ".c" t t file))))
+ (if (string-match "\\.\\(c\\|m\\)\\'" file)
+ (concat "src/" file)
+ file)))))
+
+(defface help-argument-name '((((supports :slant italic)) :inherit italic))
+ "Face to highlight argument names in *Help* buffers."
+ :group 'help)
+
+(defun help-default-arg-highlight (arg)
+ "Default function to highlight arguments in *Help* buffers.
+It returns ARG in face `help-argument-name'; ARG is also
+downcased if it displays differently than the default
+face (according to `face-differs-from-default-p')."
+ (propertize (if (face-differs-from-default-p 'help-argument-name)
+ (downcase arg)
+ arg)
+ 'face 'help-argument-name))
+
+(defun help-do-arg-highlight (doc args)
+ (with-syntax-table (make-syntax-table emacs-lisp-mode-syntax-table)
+ (modify-syntax-entry ?\- "w")
+ (dolist (arg args doc)
+ (setq doc (replace-regexp-in-string
+ ;; This is heuristic, but covers all common cases
+ ;; except ARG1-ARG2
+ (concat "\\<" ; beginning of word
+ "\\(?:[a-z-]*-\\)?" ; for xxx-ARG
+ "\\("
+ (regexp-quote arg)
+ "\\)"
+ "\\(?:es\\|s\\|th\\)?" ; for ARGth, ARGs
+ "\\(?:-[a-z0-9-]+\\)?" ; for ARG-xxx, ARG-n
+ "\\(?:-[{([<`\"].*?\\)?"; for ARG-{x}, (x), <x>, [x], `x'
+ "\\>") ; end of word
+ (help-default-arg-highlight arg)
+ doc t t 1)))))
+
+(defun help-highlight-arguments (usage doc &rest args)
+ (when usage
+ (with-temp-buffer
+ (insert usage)
+ (goto-char (point-min))
+ (let ((case-fold-search nil)
+ (next (not (or args (looking-at "\\["))))
+ (opt nil))
+ ;; Make a list of all arguments
+ (skip-chars-forward "^ ")
+ (while next
+ (or opt (not (looking-at " &")) (setq opt t))
+ (if (not (re-search-forward " \\([\\[(]*\\)\\([^] &)\.]+\\)" nil t))
+ (setq next nil)
+ (setq args (cons (match-string 2) args))
+ (when (and opt (string= (match-string 1) "("))
+ ;; A pesky CL-style optional argument with default value,
+ ;; so let's skip over it
+ (search-backward "(")
+ (goto-char (scan-sexps (point) 1)))))
+ ;; Highlight aguments in the USAGE string
+ (setq usage (help-do-arg-highlight (buffer-string) args))
+ ;; Highlight arguments in the DOC string
+ (setq doc (and doc (help-do-arg-highlight doc args))))))
+ ;; Return value is like the one from help-split-fundoc, but highlighted
+ (cons usage doc))
+
+;; The following function was compiled from the former functions
+;; `describe-simplify-lib-file-name' and `find-source-lisp-file' with
+;; some excerpts from `describe-function-1' and `describe-variable'.
+;; The only additional twists provided are (1) locate the defining file
+;; for autoloaded functions, and (2) give preference to files in the
+;; "install directory" (directories found via `load-path') rather than
+;; to files in the "compile directory" (directories found by searching
+;; the loaddefs.el file). We autoload it because it's also used by
+;; `describe-face' (instead of `describe-simplify-lib-file-name').
+
+;;;###autoload
+(defun find-lisp-object-file-name (object type)
+ "Guess the file that defined the Lisp object OBJECT, of type TYPE.
+OBJECT should be a symbol associated with a function, variable, or face;
+ alternatively, it can be a function definition.
+If TYPE is `variable', search for a variable definition.
+If TYPE is `face', search for a face definition.
+If TYPE is the value returned by `symbol-function' for a function symbol,
+ search for a function definition.
+
+The return value is the absolute name of a readable file where OBJECT is
+defined. If several such files exist, preference is given to a file
+found via `load-path'. The return value can also be `C-source', which
+means that OBJECT is a function or variable defined in C. If no
+suitable file is found, return nil."
+ (let* ((autoloaded (eq (car-safe type) 'autoload))
+ (file-name (or (and autoloaded (nth 1 type))
+ (symbol-file
+ object (if (memq type (list 'defvar 'defface))
+ type
+ 'defun)))))
+ (cond
+ (autoloaded
+ ;; An autoloaded function: Locate the file since `symbol-function'
+ ;; has only returned a bare string here.
+ (setq file-name
+ (locate-file file-name load-path '(".el" ".elc") 'readable)))
+ ((and (stringp file-name)
+ (string-match "[.]*loaddefs.el\\'" file-name))
+ ;; An autoloaded variable or face. Visit loaddefs.el in a buffer
+ ;; and try to extract the defining file. The following form is
+ ;; from `describe-function-1' and `describe-variable'.
+ (let ((location
+ (condition-case nil
+ (find-function-search-for-symbol object nil file-name)
+ (error nil))))
+ (when location
+ (with-current-buffer (car location)
+ (goto-char (cdr location))
+ (when (re-search-backward
+ "^;;; Generated autoloads from \\(.*\\)" nil t)
+ (setq file-name
+ (locate-file
+ (match-string-no-properties 1)
+ load-path nil 'readable))))))))
+
+ (cond
+ ((and (not file-name) (subrp type))
+ ;; A built-in function. The form is from `describe-function-1'.
+ (if (get-buffer " *DOC*")
+ (help-C-file-name type 'subr)
+ 'C-source))
+ ((and (not file-name) (symbolp object)
+ (integerp (get object 'variable-documentation)))
+ ;; A variable defined in C. The form is from `describe-variable'.
+ (if (get-buffer " *DOC*")
+ (help-C-file-name object 'var)
+ 'C-source))
+ ((not (stringp file-name))
+ ;; If we don't have a file-name string by now, we lost.
+ nil)
+ ((let ((lib-name
+ (if (string-match "[.]elc\\'" file-name)
+ (substring-no-properties file-name 0 -1)
+ file-name)))
+ ;; When the Elisp source file can be found in the install
+ ;; directory return the name of that file - `file-name' should
+ ;; have become an absolute file name ny now.
+ (or (and (file-readable-p lib-name) lib-name)
+ ;; The library might be compressed.
+ (and (file-readable-p (concat lib-name ".gz")) lib-name))))
+ ((let* ((lib-name (file-name-nondirectory file-name))
+ ;; The next form is from `describe-simplify-lib-file-name'.
+ (file-name
+ ;; Try converting the absolute file name to a library
+ ;; name, convert that back to a file name and see if we
+ ;; get the original one. If so, they are equivalent.
+ (if (equal file-name (locate-file lib-name load-path '("")))
+ (if (string-match "[.]elc\\'" lib-name)
+ (substring-no-properties lib-name 0 -1)
+ lib-name)
+ file-name))
+ ;; The next three forms are from `find-source-lisp-file'.
+ (elc-file (locate-file
+ (concat file-name
+ (if (string-match "\\.el\\'" file-name)
+ "c"
+ ".elc"))
+ load-path nil 'readable))
+ (str (when elc-file
+ (with-temp-buffer
+ (insert-file-contents-literally elc-file nil 0 256)
+ (buffer-string))))
+ (src-file (and str
+ (string-match ";;; from file \\(.*\\.el\\)" str)
+ (match-string 1 str))))
+ (and src-file (file-readable-p src-file) src-file))))))
+
+(declare-function ad-get-advice-info "advice" (function))
+
+;;;###autoload
+(defun describe-function-1 (function)
+ (let* ((advised (and (symbolp function) (featurep 'advice)
+ (ad-get-advice-info function)))
+ ;; If the function is advised, use the symbol that has the
+ ;; real definition, if that symbol is already set up.
+ (real-function
+ (or (and advised
+ (let ((origname (cdr (assq 'origname advised))))
+ (and (fboundp origname) origname)))
+ function))
+ ;; Get the real definition.
+ (def (if (symbolp real-function)
+ (symbol-function real-function)
+ function))
+ file-name string
+ (beg (if (commandp def) "an interactive " "a "))
+ (pt1 (with-current-buffer (help-buffer) (point)))
+ errtype)
+ (setq string
+ (cond ((or (stringp def)
+ (vectorp def))
+ "a keyboard macro")
+ ((subrp def)
+ (if (eq 'unevalled (cdr (subr-arity def)))
+ (concat beg "special form")
+ (concat beg "built-in function")))
+ ((byte-code-function-p def)
+ (concat beg "compiled Lisp function"))
+ ((symbolp def)
+ (while (and (fboundp def)
+ (symbolp (symbol-function def)))
+ (setq def (symbol-function def)))
+ ;; Handle (defalias 'foo 'bar), where bar is undefined.
+ (or (fboundp def) (setq errtype 'alias))
+ (format "an alias for `%s'" def))
+ ((eq (car-safe def) 'lambda)
+ (concat beg "Lisp function"))
+ ((eq (car-safe def) 'macro)
+ "a Lisp macro")
+ ((eq (car-safe def) 'autoload)
+ (format "%s autoloaded %s"
+ (if (commandp def) "an interactive" "an")
+ (if (eq (nth 4 def) 'keymap) "keymap"
+ (if (nth 4 def) "Lisp macro" "Lisp function"))))
+ ((keymapp def)
+ (let ((is-full nil)
+ (elts (cdr-safe def)))
+ (while elts
+ (if (char-table-p (car-safe elts))
+ (setq is-full t
+ elts nil))
+ (setq elts (cdr-safe elts)))
+ (if is-full
+ "a full keymap"
+ "a sparse keymap")))
+ (t "")))
+ (princ string)
+ (if (eq errtype 'alias)
+ (princ ",\nwhich is not defined. Please make a bug report.")
+ (with-current-buffer standard-output
+ (save-excursion
+ (save-match-data
+ (when (re-search-backward "alias for `\\([^`']+\\)'" nil t)
+ (help-xref-button 1 'help-function def)))))
+
+ (setq file-name (find-lisp-object-file-name function def))
+ (when file-name
+ (princ " in `")
+ ;; We used to add .el to the file name,
+ ;; but that's completely wrong when the user used load-file.
+ (princ (if (eq file-name 'C-source) "C source code" file-name))
+ (princ "'")
+ ;; Make a hyperlink to the library.
+ (with-current-buffer standard-output
+ (save-excursion
+ (re-search-backward "`\\([^`']+\\)'" nil t)
+ (help-xref-button 1 'help-function-def real-function file-name))))
+ (princ ".")
+ (with-current-buffer (help-buffer)
+ (fill-region-as-paragraph (save-excursion (goto-char pt1) (forward-line 0) (point))
+ (point)))
+ (terpri)(terpri)
+ (when (commandp function)
+ (let ((pt2 (with-current-buffer (help-buffer) (point))))
+ (if (and (eq function 'self-insert-command)
+ (eq (key-binding "a") 'self-insert-command)
+ (eq (key-binding "b") 'self-insert-command)
+ (eq (key-binding "c") 'self-insert-command))
+ (princ "It is bound to many ordinary text characters.\n")
+ (let* ((remapped (command-remapping function))
+ (keys (where-is-internal
+ (or remapped function) overriding-local-map nil nil))
+ non-modified-keys)
+ ;; Which non-control non-meta keys run this command?
+ (dolist (key keys)
+ (if (member (event-modifiers (aref key 0)) '(nil (shift)))
+ (push key non-modified-keys)))
+ (when remapped
+ (princ "It is remapped to `")
+ (princ (symbol-name remapped))
+ (princ "'"))
+
+ (when keys
+ (princ (if remapped ", which is bound to " "It is bound to "))
+ ;; If lots of ordinary text characters run this command,
+ ;; don't mention them one by one.
+ (if (< (length non-modified-keys) 10)
+ (princ (mapconcat 'key-description keys ", "))
+ (dolist (key non-modified-keys)
+ (setq keys (delq key keys)))
+ (if keys
+ (progn
+ (princ (mapconcat 'key-description keys ", "))
+ (princ ", and many ordinary text characters"))
+ (princ "many ordinary text characters"))))
+ (when (or remapped keys non-modified-keys)
+ (princ ".")
+ (terpri))))
+ (with-current-buffer (help-buffer) (fill-region-as-paragraph pt2 (point)))
+ (terpri)))
+ (let* ((arglist (help-function-arglist def))
+ (doc (documentation function))
+ (usage (help-split-fundoc doc function)))
+ (with-current-buffer standard-output
+ ;; If definition is a keymap, skip arglist note.
+ (unless (keymapp function)
+ (let* ((use (cond
+ (usage (setq doc (cdr usage)) (car usage))
+ ((listp arglist)
+ (format "%S" (help-make-usage function arglist)))
+ ((stringp arglist) arglist)
+ ;; Maybe the arglist is in the docstring of a symbol
+ ;; this one is aliased to.
+ ((let ((fun real-function))
+ (while (and (symbolp fun)
+ (setq fun (symbol-function fun))
+ (not (setq usage (help-split-fundoc
+ (documentation fun)
+ function)))))
+ usage)
+ (car usage))
+ ((or (stringp def)
+ (vectorp def))
+ (format "\nMacro: %s" (format-kbd-macro def)))
+ (t "[Missing arglist. Please make a bug report.]")))
+ (high (help-highlight-arguments use doc)))
+ (let ((fill-begin (point)))
+ (insert (car high) "\n")
+ (fill-region fill-begin (point)))
+ (setq doc (cdr high))))
+ (let* ((obsolete (and
+ ;; function might be a lambda construct.
+ (symbolp function)
+ (get function 'byte-obsolete-info)))
+ (use (car obsolete)))
+ (when obsolete
+ (princ "\nThis function is obsolete")
+ (when (nth 2 obsolete)
+ (insert (format " since %s" (nth 2 obsolete))))
+ (insert (cond ((stringp use) (concat ";\n" use))
+ (use (format ";\nuse `%s' instead." use))
+ (t "."))
+ "\n"))
+ (insert "\n"
+ (or doc "Not documented."))))))))
+
+
+;; Variables
+
+;;;###autoload
+(defun variable-at-point (&optional any-symbol)
+ "Return the bound variable symbol found at or before point.
+Return 0 if there is no such symbol.
+If ANY-SYMBOL is non-nil, don't insist the symbol be bound."
+ (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) (boundp obj) obj)))
+ (error nil))
+ (let* ((str (find-tag-default))
+ (sym (if str (intern-soft str))))
+ (if (and sym (or any-symbol (boundp sym)))
+ sym
+ (save-match-data
+ (when (and str (string-match "\\`\\W*\\(.*?\\)\\W*\\'" str))
+ (setq sym (intern-soft (match-string 1 str)))
+ (and (or any-symbol (boundp sym)) sym)))))
+ 0)))
+
+(defun describe-variable-custom-version-info (variable)
+ (let ((custom-version (get variable 'custom-version))
+ (cpv (get variable 'custom-package-version))
+ (output nil))
+ (if custom-version
+ (setq output
+ (format "This variable was introduced, or its default value was changed, in\nversion %s of Emacs.\n"
+ custom-version))
+ (when cpv
+ (let* ((package (car-safe cpv))
+ (version (if (listp (cdr-safe cpv))
+ (car (cdr-safe cpv))
+ (cdr-safe cpv)))
+ (pkg-versions (assq package customize-package-emacs-version-alist))
+ (emacsv (cdr (assoc version pkg-versions))))
+ (if (and package version)
+ (setq output
+ (format (concat "This variable was introduced, or its default value was changed, in\nversion %s of the %s package"
+ (if emacsv
+ (format " that is part of Emacs %s" emacsv))
+ ".\n")
+ version package))))))
+ output))
+
+;;;###autoload
+(defun describe-variable (variable &optional buffer frame)
+ "Display the full documentation of VARIABLE (a symbol).
+Returns the documentation as a string, also.
+If VARIABLE has a buffer-local value in BUFFER or FRAME
+\(default to the current buffer and current frame),
+it is displayed along with the global value."
+ (interactive
+ (let ((v (variable-at-point))
+ (enable-recursive-minibuffers t)
+ val)
+ (setq val (completing-read (if (symbolp v)
+ (format
+ "Describe variable (default %s): " v)
+ "Describe variable: ")
+ obarray
+ '(lambda (vv)
+ (or (boundp vv)
+ (get vv 'variable-documentation)))
+ t nil nil
+ (if (symbolp v) (symbol-name v))))
+ (list (if (equal val "")
+ v (intern val)))))
+ (let (file-name)
+ (unless (buffer-live-p buffer) (setq buffer (current-buffer)))
+ (unless (frame-live-p frame) (setq frame (selected-frame)))
+ (if (not (symbolp variable))
+ (message "You did not specify a variable")
+ (save-excursion
+ (let ((valvoid (not (with-current-buffer buffer (boundp variable))))
+ val val-start-pos locus)
+ ;; Extract the value before setting up the output buffer,
+ ;; in case `buffer' *is* the output buffer.
+ (unless valvoid
+ (with-selected-frame frame
+ (with-current-buffer buffer
+ (setq val (symbol-value variable)
+ locus (variable-binding-locus variable)))))
+ (help-setup-xref (list #'describe-variable variable buffer)
+ (interactive-p))
+ (with-help-window (help-buffer)
+ (with-current-buffer buffer
+ (prin1 variable)
+ (setq file-name (find-lisp-object-file-name variable 'defvar))
+
+ (if file-name
+ (progn
+ (princ " is a variable defined in `")
+ (princ (if (eq file-name 'C-source) "C source code" file-name))
+ (princ "'.\n")
+ (with-current-buffer standard-output
+ (save-excursion
+ (re-search-backward "`\\([^`']+\\)'" nil t)
+ (help-xref-button 1 'help-variable-def
+ variable file-name)))
+ (if valvoid
+ (princ "It is void as a variable.")
+ (princ "Its ")))
+ (if valvoid
+ (princ " is void as a variable.")
+ (princ "'s "))))
+ (if valvoid
+ nil
+ (with-current-buffer standard-output
+ (setq val-start-pos (point))
+ (princ "value is ")
+ (terpri)
+ (let ((from (point)))
+ (pp val)
+ ;; Hyperlinks in variable's value are quite frequently
+ ;; inappropriate e.g C-h v <RET> features <RET>
+ ;; (help-xref-on-pp from (point))
+ (if (< (point) (+ from 20))
+ (delete-region (1- from) from)))))
+ (terpri)
+
+ (when locus
+ (if (bufferp locus)
+ (princ (format "%socal in buffer %s; "
+ (if (get variable 'permanent-local)
+ "Permanently l" "L")
+ (buffer-name)))
+ (princ (format "It is a frame-local variable; ")))
+ (if (not (default-boundp variable))
+ (princ "globally void")
+ (let ((val (default-value variable)))
+ (with-current-buffer standard-output
+ (princ "global value is ")
+ (terpri)
+ ;; Fixme: pp can take an age if you happen to
+ ;; ask for a very large expression. We should
+ ;; probably print it raw once and check it's a
+ ;; sensible size before prettyprinting. -- fx
+ (let ((from (point)))
+ (pp val)
+ ;; See previous comment for this function.
+ ;; (help-xref-on-pp from (point))
+ (if (< (point) (+ from 20))
+ (delete-region (1- from) from))))))
+ (terpri))
+
+ ;; If the value is large, move it to the end.
+ (with-current-buffer standard-output
+ (when (> (count-lines (point-min) (point-max)) 10)
+ ;; Note that setting the syntax table like below
+ ;; makes forward-sexp move over a `'s' at the end
+ ;; of a symbol.
+ (set-syntax-table emacs-lisp-mode-syntax-table)
+ (goto-char val-start-pos)
+ ;; The line below previously read as
+ ;; (delete-region (point) (progn (end-of-line) (point)))
+ ;; which suppressed display of the buffer local value for
+ ;; large values.
+ (when (looking-at "value is") (replace-match ""))
+ (save-excursion
+ (insert "\n\nValue:")
+ (set (make-local-variable 'help-button-cache)
+ (point-marker)))
+ (insert "value is shown ")
+ (insert-button "below"
+ 'action help-button-cache
+ 'follow-link t
+ 'help-echo "mouse-2, RET: show value")
+ (insert ".\n")))
+ (terpri)
+
+ (let* ((alias (condition-case nil
+ (indirect-variable variable)
+ (error variable)))
+ (obsolete (get variable 'byte-obsolete-variable))
+ (use (car obsolete))
+ (safe-var (get variable 'safe-local-variable))
+ (doc (or (documentation-property variable 'variable-documentation)
+ (documentation-property alias 'variable-documentation)))
+ (extra-line nil))
+ ;; Add a note for variables that have been make-var-buffer-local.
+ (when (and (local-variable-if-set-p variable)
+ (or (not (local-variable-p variable))
+ (with-temp-buffer
+ (local-variable-if-set-p variable))))
+ (setq extra-line t)
+ (princ " Automatically becomes buffer-local when set in any fashion.\n"))
+
+ ;; Mention if it's an alias
+ (unless (eq alias variable)
+ (setq extra-line t)
+ (princ (format " This variable is an alias for `%s'.\n" alias)))
+
+ (when obsolete
+ (setq extra-line t)
+ (princ " This variable is obsolete")
+ (if (cdr obsolete) (princ (format " since %s" (cdr obsolete))))
+ (princ (cond ((stringp use) (concat ";\n " use))
+ (use (format ";\n use `%s' instead." (car obsolete)))
+ (t ".")))
+ (terpri))
+ (when safe-var
+ (setq extra-line t)
+ (princ " This variable is safe as a file local variable ")
+ (princ "if its value\n satisfies the predicate ")
+ (princ (if (byte-code-function-p safe-var)
+ "which is byte-compiled expression.\n"
+ (format "`%s'.\n" safe-var))))
+
+ (if extra-line (terpri))
+ (princ "Documentation:\n")
+ (with-current-buffer standard-output
+ (insert (or doc "Not documented as a variable."))))
+
+ ;; Make a link to customize if this variable can be customized.
+ (when (custom-variable-p variable)
+ (let ((customize-label "customize"))
+ (terpri)
+ (terpri)
+ (princ (concat "You can " customize-label " this variable."))
+ (with-current-buffer standard-output
+ (save-excursion
+ (re-search-backward
+ (concat "\\(" customize-label "\\)") nil t)
+ (help-xref-button 1 'help-customize-variable variable))))
+ ;; Note variable's version or package version
+ (let ((output (describe-variable-custom-version-info variable)))
+ (when output
+ (terpri)
+ (terpri)
+ (princ output))))
+
+ (save-excursion
+ (set-buffer standard-output)
+ ;; Return the text we displayed.
+ (buffer-string))))))))
+
+
+;;;###autoload
+(defun describe-syntax (&optional buffer)
+ "Describe the syntax specifications in the syntax table of BUFFER.
+The descriptions are inserted in a help buffer, which is then displayed.
+BUFFER defaults to the current buffer."
+ (interactive)
+ (setq buffer (or buffer (current-buffer)))
+ (help-setup-xref (list #'describe-syntax buffer) (interactive-p))
+ (with-help-window (help-buffer)
+ (let ((table (with-current-buffer buffer (syntax-table))))
+ (with-current-buffer standard-output
+ (describe-vector table 'internal-describe-syntax-value)
+ (while (setq table (char-table-parent table))
+ (insert "\nThe parent syntax table is:")
+ (describe-vector table 'internal-describe-syntax-value))))))
+
+(defun help-describe-category-set (value)
+ (insert (cond
+ ((null value) "default")
+ ((char-table-p value) "deeper char-table ...")
+ (t (condition-case err
+ (category-set-mnemonics value)
+ (error "invalid"))))))
+
+;;;###autoload
+(defun describe-categories (&optional buffer)
+ "Describe the category specifications in the current category table.
+The descriptions are inserted in a buffer, which is then displayed.
+If BUFFER is non-nil, then describe BUFFER's category table instead.
+BUFFER should be a buffer or a buffer name."
+ (interactive)
+ (setq buffer (or buffer (current-buffer)))
+ (help-setup-xref (list #'describe-categories buffer) (interactive-p))
+ (with-help-window (help-buffer)
+ (let ((table (with-current-buffer buffer (category-table))))
+ (with-current-buffer standard-output
+ (describe-vector table 'help-describe-category-set)
+ (let ((docs (char-table-extra-slot table 0)))
+ (if (or (not (vectorp docs)) (/= (length docs) 95))
+ (insert "Invalid first extra slot in this char table\n")
+ (insert "Meanings of mnemonic characters are:\n")
+ (dotimes (i 95)
+ (let ((elt (aref docs i)))
+ (when elt
+ (insert (+ i ?\s) ": " elt "\n"))))
+ (while (setq table (char-table-parent table))
+ (insert "\nThe parent category table is:")
+ (describe-vector table 'help-describe-category-set))))))))
+
+(provide 'help-fns)
+
+;; arch-tag: 9e10331c-ae81-4d13-965d-c4819aaab0b3
+;;; help-fns.el ends here
|