;;; help-fns.el --- Complex help functions
-;; Copyright (C) 1985, 1986, 1993, 1994, 1998, 1999, 2000, 2001
+;; Copyright (C) 1985, 1986, 1993, 1994, 1998, 1999, 2000, 2001, 2002
;; Free Software Foundation, Inc.
;; Maintainer: FSF
With arg, you are asked to choose which language."
(interactive "P")
(let ((lang (if arg
- (read-language-name 'tutorial "Language: " "English")
+ (let (completion-buffer)
+ ;; Display a completion list right away
+ ;; to guide the user.
+ (with-output-to-temp-buffer "*Completions*"
+ (display-completion-list
+ (all-completions "" language-info-alist
+ (lambda (elm)
+ (and (listp elm) (assq 'tutorial elm)))))
+ (setq completion-buffer standard-output))
+ ;; Arrange to set completion-reference-buffer
+ ;; in *Completions* to point to the minibuffer,
+ ;; after entering the minibuffer.
+ (let ((minibuffer-setup-hook minibuffer-setup-hook))
+ (add-hook 'minibuffer-setup-hook
+ (lambda ()
+ (let ((mini (current-buffer)))
+ (with-current-buffer completion-buffer
+ (make-local-variable 'completion-reference-buffer)
+ (setq completion-reference-buffer
+ mini)))))
+ (read-language-name 'tutorial "Language: " "English")))
(if (get-language-info current-language-environment 'tutorial)
current-language-environment
"English")))
;;;###autoload
(defun locate-library (library &optional nosuffix path interactive-call)
"Show the precise file name of Emacs library LIBRARY.
-This command searches the directories in `load-path' like `M-x load-library'
-to find the file that `M-x load-library RET LIBRARY RET' would load.
+This command searches the directories in `load-path' like `\\[load-library]'
+to find the file that `\\[load-library] RET LIBRARY RET' would load.
Optional second arg NOSUFFIX non-nil means don't add suffixes `load-suffixes'
to the specified name LIBRARY.
When called from a program, the file name is normaly returned as a
string. When run interactively, the argument INTERACTIVE-CALL is t,
and the file name is displayed in the echo area."
- (interactive (list (read-string "Locate library: ")
+ (interactive (list (completing-read "Locate library: "
+ 'locate-file-completion
+ (cons load-path load-suffixes))
nil nil
t))
- (catch 'answer
- (dolist (dir (or path load-path))
- (dolist (suf (append (unless nosuffix load-suffixes) '("")))
- (let ((try (expand-file-name (concat library suf) dir)))
- (and (file-readable-p try)
- (null (file-directory-p try))
- (progn
- (if interactive-call
- (message "Library is file %s" (abbreviate-file-name try)))
- (throw 'answer try))))))
+ (let ((file (locate-file library
+ (or path load-path)
+ (append (unless nosuffix load-suffixes) '("")))))
(if interactive-call
- (message "No library %s in search path" library))
- nil))
+ (if file
+ (message "Library is file %s" (abbreviate-file-name file))
+ (message "No library %s in search path" library)))
+ file))
\f
;; Functions
;; Return the text we displayed.
(buffer-string))))))
+(defun help-split-fundoc (doc def)
+ "Split a function docstring DOC 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 DOC."
+ ;; 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 doc
+ (let* ((rep (prin1-to-string (indirect-function def)))
+ (name (if (string-match " \\([^ ]+\\)>$" rep)
+ (match-string 1 rep) (prin1-to-string def))))
+ (if (string-match (format "\n\n(\\(fn\\|%s\\)\\(\\( .*\\)?)\\)\\'"
+ (regexp-quote name))
+ doc)
+ (cons (format "(%s%s"
+ ;; Replace `fn' with the actual function name.
+ (if (consp def) "anonymous" def)
+ (match-string 2 doc))
+ (substring doc 0 (match-beginning 0)))))))
+
+(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)))
+
;;;###autoload
(defun describe-function-1 (function)
(let* ((def (if (symbolp function)
(if (eq (nth 4 def) 'keymap) "keymap"
(if (nth 4 def) "Lisp macro" "Lisp function"))
))
- ;; perhaps use keymapp here instead
- ((eq (car-safe def) 'keymap)
+ ((keymapp def)
(let ((is-full nil)
(elts (cdr-safe def)))
(while elts
;; This is necessary only for defaliases.
(let ((location
(condition-case nil
- (find-function-search-for-symbol function nil "loaddefs.el")
+ (find-function-search-for-symbol function nil "loaddefs.el")
(error nil))))
(when location
(with-current-buffer (car location)
(when (or remapped keys)
(princ ".")
(terpri))))
- ;; Handle symbols aliased to other symbols.
- (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)))
- (let ((arglist (cond ((byte-code-function-p def)
- (car (append def nil)))
- ((eq (car-safe def) 'lambda)
- (nth 1 def))
- ((and (eq (car-safe def) 'autoload)
- (not (eq (nth 4 def) 'keymap)))
- (concat "[Arg list not available until "
- "function definition is loaded.]"))
- (t t))))
- (cond ((listp arglist)
- (princ (cons (if (symbolp function) function "anonymous")
- (mapcar (lambda (arg)
- (if (memq arg '(&optional &rest))
- arg
- (intern (upcase (symbol-name arg)))))
- arglist)))
- (terpri))
- ((stringp arglist)
- (princ arglist)
- (terpri))))
- (let ((doc (documentation function)))
- (if doc
- (progn (terpri)
- (princ doc)
- (if (subrp def)
- (with-current-buffer standard-output
- (beginning-of-line)
- ;; Builtins get the calling sequence at the end of
- ;; the doc string. Move it to the same place as
- ;; for other functions.
-
- ;; In cases where `function' has been fset to a
- ;; subr we can't search for function's name in
- ;; the doc string. Kluge round that using the
- ;; printed representation. The arg list then
- ;; shows the wrong function name, but that
- ;; might be a useful hint.
- (let* ((rep (prin1-to-string def))
- (name (progn
- (string-match " \\([^ ]+\\)>$" rep)
- (match-string 1 rep))))
- (if (looking-at (format "(%s[ )]" (regexp-quote name)))
- (let ((start (point-marker)))
- (goto-char (point-min))
- (forward-paragraph)
- (insert-buffer-substring (current-buffer) start)
- (insert ?\n)
- (delete-region (1- start) (point-max)))
- (goto-char (point-min))
- (forward-paragraph)
- (insert
- "[Missing arglist. Please make a bug report.]\n")))
- (goto-char (point-max)))))
- (princ "not documented")))))
+ (let* ((arglist (help-function-arglist def))
+ (doc (documentation function))
+ (usage (help-split-fundoc doc function)))
+ ;; If definition is a keymap, skip arglist note.
+ (unless (keymapp def)
+ (princ (cond
+ (usage (setq doc (cdr usage)) (car usage))
+ ((listp arglist) (help-make-usage function arglist))
+ ((stringp arglist) arglist)
+ ;; Maybe the arglist is in the docstring of the alias.
+ ((let ((fun function))
+ (while (and (symbolp fun)
+ (setq fun (symbol-function fun))
+ (not (setq usage (help-split-fundoc
+ (documentation fun)
+ function)))))
+ usage)
+ (car usage))
+ (t "[Missing arglist. Please make a bug report.]")))
+ (terpri))
+ (let ((obsolete (and
+ ;; function might be a lambda construct.
+ (symbolp function)
+ (get function 'byte-obsolete-info))))
+ (when obsolete
+ (terpri)
+ (princ "This function is obsolete")
+ (if (nth 2 obsolete) (princ (format " since %s" (nth 2 obsolete))))
+ (princ ";") (terpri)
+ (princ (if (stringp (car obsolete)) (car obsolete)
+ (format "use `%s' instead." (car obsolete))))
+ (terpri)))
+ (terpri)
+ (princ (or doc "Not documented.")))))
\f
;; Variables
(if (symbolp v) (symbol-name v))))
(list (if (equal val "")
v (intern val)))))
- (unless (bufferp buffer) (setq buffer (current-buffer)))
+ (unless (buffer-live-p buffer) (setq buffer (current-buffer)))
(if (not (symbolp variable))
(message "You did not specify a variable")
(save-excursion
- (let (valvoid)
+ (let* ((valvoid (not (with-current-buffer buffer (boundp variable))))
+ ;; Extract the value before setting up the output buffer,
+ ;; in case `buffer' *is* the output buffer.
+ (val (unless valvoid (buffer-local-value variable buffer))))
(help-setup-xref (list #'describe-variable variable buffer)
(interactive-p))
(with-output-to-temp-buffer (help-buffer)
(with-current-buffer buffer
(prin1 variable)
- (if (not (boundp variable))
- (progn
- (princ " is void")
- (setq valvoid t))
- (let ((val (symbol-value variable)))
- (with-current-buffer standard-output
- (princ "'s value is ")
- (terpri)
- (let ((from (point)))
- (pp val)
- (help-xref-on-pp from (point))
- (if (< (point) (+ from 20))
- (save-excursion
- (goto-char from)
- (delete-char -1)))))))
+ (if valvoid
+ (princ " is void")
+ (with-current-buffer standard-output
+ (princ "'s value is ")
+ (terpri)
+ (let ((from (point)))
+ (pp val)
+ (help-xref-on-pp from (point))
+ (if (< (point) (+ from 20))
+ (delete-region (1- from) from)))))
(terpri)
(when (local-variable-p variable)
(princ (format "Local in buffer %s; " (buffer-name)))
(pp val)
(help-xref-on-pp from (point))
(if (< (point) (+ from 20))
- (save-excursion
- (goto-char from)
- (delete-char -1)))))))
+ (delete-region (1- from) from))))))
(terpri))
(terpri)
(with-current-buffer standard-output
(save-excursion
(forward-line -1)
(insert "Automatically becomes buffer-local when set in any fashion.\n"))))
- (princ "Documentation:")
- (terpri)
- (let ((doc (documentation-property variable 'variable-documentation)))
- (princ (or doc "not documented as a variable.")))
-
+ ;; Mention if it's an alias
+ (let* ((alias (condition-case nil
+ (indirect-variable variable)
+ (error variable)))
+ (obsolete (get variable 'byte-obsolete-variable))
+ (doc (or (documentation-property variable 'variable-documentation)
+ (documentation-property alias 'variable-documentation))))
+ (unless (eq alias variable)
+ (princ (format "This variable is an alias for `%s'." alias))
+ (terpri)
+ (terpri))
+ (when obsolete
+ (princ "This variable is obsolete")
+ (if (cdr obsolete) (princ (format " since %s" (cdr obsolete))))
+ (princ ";") (terpri)
+ (princ (if (stringp (car obsolete)) (car obsolete)
+ (format "use `%s' instead." (car obsolete))))
+ (terpri)
+ (terpri))
+ (princ (or doc "Not documented as a variable.")))
;; Make a link to customize if this variable can be customized.
;; Note, it is not reliable to test only for a custom-type property
;; because those are only present after the var's definition