X-Git-Url: https://code.delx.au/gnu-emacs/blobdiff_plain/72a9f8fd72a20ae8dfbf7e4202d3191733e52f04..0bfd44c1806f9e589f79e9bc8f4b2a5aab7e4df3:/lisp/emacs-lisp/eldoc.el diff --git a/lisp/emacs-lisp/eldoc.el b/lisp/emacs-lisp/eldoc.el index 26f6ce751f..805184e15d 100644 --- a/lisp/emacs-lisp/eldoc.el +++ b/lisp/emacs-lisp/eldoc.el @@ -1,159 +1,159 @@ ;;; eldoc.el --- show function arglist or variable docstring in echo area -;; Copyright (C) 1995 Noah S. Friedman +;; Copyright (C) 1996, 1997, 1998, 1999, 2000, 2002, 2003, 2004, +;; 2005, 2006 Free Software Foundation, Inc. -;; Author: Noah Friedman -;; Maintainer: friedman@prep.ai.mit.edu +;; Author: Noah Friedman +;; Maintainer: friedman@splode.com ;; Keywords: extensions -;; Status: Works in Emacs 19 and XEmacs. ;; Created: 1995-10-06 -;; LCD Archive Entry: -;; eldoc|Noah Friedman|friedman@prep.ai.mit.edu| -;; show function arglist or variable docstring in echo area| -;; $Date: 1995/11/21 15:21:34 $|$Revision: 1.4 $|~/misc/eldoc.el.gz| +;; This file is part of GNU Emacs. -;; $Id: eldoc.el,v 1.4 1995/11/21 15:21:34 friedman Exp friedman $ - -;; This program is free software; you can redistribute it and/or modify +;; GNU Emacs is free software; you can redistribute it and/or modify ;; it under the terms of the GNU General Public License as published by ;; the Free Software Foundation; either version 2, or (at your option) ;; any later version. -;; -;; This program is distributed in the hope that it will be useful, + +;; 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 this program; if not, you can either send email to this -;; program's maintainer or write to: The Free Software Foundation, -;; Inc.; 59 Temple Place, Suite 330; Boston, MA 02111-1307, USA. +;; along with GNU Emacs; see the file COPYING. If not, write to the +;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, +;; Boston, MA 02110-1301, USA. ;;; Commentary: -;; This program was inspired by the behavior of the Lisp Machine "mouse -;; documentation window"; as you type a function's symbol name as part of a -;; sexp, it will print the argument list for that function. However, this -;; program's behavior is different in a couple of significant ways. For -;; one, you need not actually type the function name; you need only move -;; point around in a sexp that calls it. However, if point is over a -;; documented variable, it will print the one-line documentation for that -;; variable instead, to remind you of that variable's purpose. +;; This program was inspired by the behavior of the "mouse documentation +;; window" on many Lisp Machine systems; as you type a function's symbol +;; name as part of a sexp, it will print the argument list for that +;; function. Behavior is not identical; for example, you need not actually +;; type the function name, you need only move point around in a sexp that +;; calls it. Also, if point is over a documented variable, it will print +;; the one-line documentation for that variable instead, to remind you of +;; that variable's meaning. ;; One useful way to enable this minor mode is to put the following in your ;; .emacs: ;; -;; (autoload 'turn-on-eldoc-mode "eldoc" nil t) ;; (add-hook 'emacs-lisp-mode-hook 'turn-on-eldoc-mode) ;; (add-hook 'lisp-interaction-mode-hook 'turn-on-eldoc-mode) +;; (add-hook 'ielm-mode-hook 'turn-on-eldoc-mode) -;;; Code: - -;;;###autoload -(defvar eldoc-mode nil - "*If non-nil, show the defined parameters for the elisp function near point. - -For the emacs lisp function at the beginning of the sexp which point is -within, show the defined parameters for the function in the echo area. -This information is extracted directly from the function or macro if it is -in pure lisp. +;; Major modes for other languages may use Eldoc by defining an +;; appropriate function as the buffer-local value of +;; `eldoc-documentation-function'. -If the emacs function is a subr, the parameters are obtained from the -documentation string if possible. +;;; Code: -If point is over a documented variable, print that variable's docstring -instead; see function `eldoc-print-var-docstring'. +(require 'help-fns) ;For fundoc-usage handling functions. -This variable is buffer-local.") -(make-variable-buffer-local 'eldoc-mode) +(defgroup eldoc nil + "Show function arglist or variable docstring in echo area." + :group 'lisp + :group 'extensions) -(defvar eldoc-idle-delay 0.50 +(defcustom eldoc-idle-delay 0.50 "*Number of seconds of idle time to wait before printing. If user input arrives before this interval of time has elapsed after the last input, no documentation will be printed. -If this variable is set to 0, no idle time is required.") +If this variable is set to 0, no idle time is required." + :type 'number + :group 'eldoc) -(defvar eldoc-argument-case 'upcase +;;;###autoload +(defcustom eldoc-minor-mode-string " ElDoc" + "*String to display in mode line when Eldoc Mode is enabled; nil for none." + :type '(choice string (const :tag "None" nil)) + :group 'eldoc) + +(defcustom eldoc-argument-case 'upcase "Case to display argument names of functions, as a symbol. This has two preferred values: `upcase' or `downcase'. Actually, any name of a function which takes a string as an argument and -returns another string is acceptable.") - -(defvar eldoc-mode-message-commands nil - "*Obarray of command names where it is appropriate to print in the echo area. - -This is not done for all commands since some print their own -messages in the echo area, and these functions would instantly overwrite -them. But self-insert-command as well as most motion commands are good -candidates. - -It is probably best to manipulate this data structure with the commands -`eldoc-add-command' and `eldoc-remove-command'.") - -(cond ((null eldoc-mode-message-commands) - ;; If you increase the number of buckets, keep it a prime number. - (setq eldoc-mode-message-commands (make-vector 31 0)) - (let ((list '("self-insert-command" - "next-" "previous-" - "forward-" "backward-" - "beginning-of-" "end-of-" - "goto-" - "recenter" - "scroll-")) - (syms nil)) - (while list - (setq syms (all-completions (car list) obarray 'fboundp)) - (setq list (cdr list)) - (while syms - (set (intern (car syms) eldoc-mode-message-commands) t) - (setq syms (cdr syms))))))) - -;; Bookkeeping; the car contains the last symbol read from the buffer. -;; The cdr contains the string last displayed in the echo area, so it can -;; be printed again if necessary without reconsing. -(defvar eldoc-last-data '(nil . nil)) - -(defvar eldoc-minor-mode-string " ElDoc" - "*String to display in mode line when Eldoc Mode is enabled.") - -;; Put this minor mode on the global minor-mode-alist. -(or (assq 'eldoc-mode (default-value 'minor-mode-alist)) - (setq-default minor-mode-alist - (append (default-value 'minor-mode-alist) - '((eldoc-mode eldoc-minor-mode-string))))) - -;; In emacs 19.29 and later, and XEmacs 19.13 and later, all messages are -;; recorded in a log. Do not put eldoc messages in that log since -;; they are Legion. -(defmacro eldoc-message (&rest args) - (if (fboundp 'display-message) - ;; XEmacs 19.13 way of preventing log messages. - (list 'display-message '(quote no-log) (apply 'list 'format args)) - (list 'let (list (list 'message-log-max 'nil)) - (apply 'list 'message args)))) +returns another string is acceptable." + :type '(radio (function-item upcase) + (function-item downcase) + function) + :group 'eldoc) + +(defcustom eldoc-echo-area-use-multiline-p 'truncate-sym-name-if-fit + "*Allow long eldoc messages to resize echo area display. +If value is t, never attempt to truncate messages; complete symbol name +and function arglist or 1-line variable documentation will be displayed +even if echo area must be resized to fit. + +If value is any non-nil value other than t, symbol name may be truncated +if it will enable the function arglist or documentation string to fit on a +single line without resizing window. Otherwise, behavior is just like +former case. + +If value is nil, messages are always truncated to fit in a single line of +display in the echo area. Function or variable symbol name may be +truncated to make more of the arglist or documentation string visible." + :type '(radio (const :tag "Always" t) + (const :tag "Never" nil) + (const :tag "Yes, but truncate symbol names if it will\ + enable argument list to fit on one line" truncate-sym-name-if-fit)) + :group 'eldoc) + +;;; No user options below here. + +(defvar eldoc-message-commands-table-size 31 + "This is used by eldoc-add-command to initialize eldoc-message-commands +as an obarray. +It should probably never be necessary to do so, but if you +choose to increase the number of buckets, you must do so before loading +this file since the obarray is initialized at load time. +Remember to keep it a prime number to improve hash performance.") + +(defconst eldoc-message-commands + (make-vector eldoc-message-commands-table-size 0) + "Commands after which it is appropriate to print in the echo area. +Eldoc does not try to print function arglists, etc. after just any command, +because some commands print their own messages in the echo area and these +functions would instantly overwrite them. But self-insert-command as well +as most motion commands are good candidates. +This variable contains an obarray of symbols; do not manipulate it +directly. Instead, use `eldoc-add-command' and `eldoc-remove-command'.") + +(defconst eldoc-last-data (make-vector 3 nil) + "Bookkeeping; elements are as follows: + 0 - contains the last symbol read from the buffer. + 1 - contains the string last displayed in the echo area for that + symbol, so it can be printed again if necessary without reconsing. + 2 - 'function if function args, 'variable if variable documentation.") +(defvar eldoc-last-message nil) + +(defvar eldoc-timer nil "eldoc's timer object.") + +(defvar eldoc-current-idle-delay eldoc-idle-delay + "idle time delay currently in use by timer. +This is used to determine if `eldoc-idle-delay' is changed by the user.") ;;;###autoload -(defun eldoc-mode (&optional prefix) - "*If non-nil, then enable eldoc-mode (see variable docstring)." - (interactive "P") - - ;; Make sure it's on the post-command-idle-hook if defined, otherwise put - ;; it on post-command-hook. The former first appeared in Emacs 19.30. - (add-hook (if (boundp 'post-command-idle-hook) - 'post-command-idle-hook - 'post-command-hook) - 'eldoc-mode-print-current-symbol-info) - - (setq eldoc-mode - (>= (prefix-numeric-value prefix) 0)) - (and (interactive-p) - (if eldoc-mode - (message "eldoc-mode is enabled") - (message "eldoc-mode is disabled"))) - eldoc-mode) +(define-minor-mode eldoc-mode + "Toggle ElDoc mode on or off. +In ElDoc mode, the echo area displays information about a +function or variable in the text where point is. If point is +on a documented variable, it displays the first line of that +variable's doc string. Otherwise it displays the argument list +of the function called in the expression point is on. + +With prefix ARG, turn ElDoc mode on if and only if ARG is positive." + :group 'eldoc :lighter eldoc-minor-mode-string + (setq eldoc-last-message nil) + (if eldoc-mode + (progn + (add-hook 'post-command-hook 'eldoc-schedule-timer nil t) + (add-hook 'pre-command-hook 'eldoc-pre-command-refresh-echo-area t)) + (remove-hook 'post-command-hook 'eldoc-schedule-timer) + (remove-hook 'pre-command-hook 'eldoc-pre-command-refresh-echo-area))) ;;;###autoload (defun turn-on-eldoc-mode () @@ -161,235 +161,224 @@ It is probably best to manipulate this data structure with the commands (interactive) (eldoc-mode 1)) -(defun eldoc-add-command (cmd) - "Add COMMAND to the list of commands which causes function arg display. -If called interactively, completion matches any bound function. - -When point is in a sexp, the function args are not reprinted in the echo -area after every possible interactive command because some of them print -their own messages in the echo area; the eldoc functions would instantly -overwrite them unless it is more restrained." - (interactive "aAdd function to eldoc message commands list: ") - (and (fboundp cmd) - (set (intern (symbol-name cmd) eldoc-mode-message-commands) t))) - -(defun eldoc-remove-command (cmd) - "Remove COMMAND from the list of commands which causes function arg display. -If called interactively, completion matches only those functions currently -in the list. - -When point is in a sexp, the function args are not reprinted in the echo -area after every possible interactive command because some of them print -their own messages in the echo area; the eldoc functions would instantly -overwrite them unless it is more restrained." - (interactive (list (completing-read - "Remove function from eldoc message commands list: " - eldoc-mode-message-commands 'boundp t))) - (and (symbolp cmd) - (setq cmd (symbol-name cmd))) - (if (fboundp 'unintern) - (unintern cmd eldoc-mode-message-commands) - (let ((s (intern-soft cmd eldoc-mode-message-commands))) - (and s - (makunbound s))))) - -(defun eldoc-mode-print-current-symbol-info () - (and eldoc-mode - (not executing-macro) - ;; Having this mode operate in the minibuffer makes it impossible to - ;; see what you're doing. - (not (eq (selected-window) (minibuffer-window))) - (sit-for eldoc-idle-delay) - (symbolp this-command) - (intern-soft (symbol-name this-command) eldoc-mode-message-commands) - (let ((current-symbol (eldoc-current-symbol)) - (current-fnsym (eldoc-fnsym-in-current-sexp))) - (cond ((eq current-symbol current-fnsym) - (eldoc-print-fnsym-args current-fnsym)) - (t - (or (eldoc-print-var-docstring current-symbol) - (eldoc-print-fnsym-args current-fnsym))))))) - -(defun eldoc-print-var-docstring (&optional sym) - "Print the brief (one-line) documentation string for the variable at point. -If called with no argument, print the first line of the variable -documentation string for the symbol at point in the echo area. -If called with a symbol, print the line for that symbol. - -If the entire line cannot fit in the echo area, the variable name may be -truncated or eliminated entirely from the output to make room. -Any leading `*' in the docstring (which indicates the variable is a user -option) is not printed." - (interactive) - (let* ((s (or sym (eldoc-current-symbol))) - (name (symbol-name s)) - (doc (and s (documentation-property s 'variable-documentation t)))) - (and doc - (save-match-data - (and (string-match "\n" doc) - (setq doc (substring doc 0 (match-beginning 0)))) - (and (string-match "^\\*" doc) - (setq doc (substring doc 1))) - (let* ((doclen (+ (length name) (length ": ") (length doc))) - ;; Subtract 1 from window width since emacs seems not to - ;; write any chars to the last column, at least for some - ;; terminal types. - (strip (- doclen (1- (window-width (minibuffer-window)))))) - (cond ((> strip 0) - (let* ((len (length name))) - (cond ((>= strip len) - (eldoc-message "%s" doc)) - (t - (setq name (substring name 0 (- len strip))) - (eldoc-message "%s: %s" name doc))))) - (t - (eldoc-message "%s: %s" s doc)))) - t)))) +(defun eldoc-schedule-timer () + (or (and eldoc-timer + (memq eldoc-timer timer-idle-list)) + (setq eldoc-timer + (run-with-idle-timer eldoc-idle-delay t + 'eldoc-print-current-symbol-info))) + + ;; If user has changed the idle delay, update the timer. + (cond ((not (= eldoc-idle-delay eldoc-current-idle-delay)) + (setq eldoc-current-idle-delay eldoc-idle-delay) + (timer-set-idle-time eldoc-timer eldoc-idle-delay t)))) + +(defun eldoc-message (&rest args) + (let ((omessage eldoc-last-message)) + (setq eldoc-last-message + (cond ((eq (car args) eldoc-last-message) eldoc-last-message) + ((null (car args)) nil) + ;; If only one arg, no formatting to do, so put it in + ;; eldoc-last-message so eq test above might succeed on + ;; subsequent calls. + ((null (cdr args)) (car args)) + (t (apply 'format args)))) + ;; In emacs 19.29 and later, and XEmacs 19.13 and later, all messages + ;; are recorded in a log. Do not put eldoc messages in that log since + ;; they are Legion. + ;; Emacs way of preventing log messages. + (let ((message-log-max nil)) + (cond (eldoc-last-message (message "%s" eldoc-last-message)) + (omessage (message nil))))) + eldoc-last-message) + +;; This function goes on pre-command-hook for XEmacs or when using idle +;; timers in Emacs. Motion commands clear the echo area for some reason, +;; which make eldoc messages flicker or disappear just before motion +;; begins. This function reprints the last eldoc message immediately +;; before the next command executes, which does away with the flicker. +;; This doesn't seem to be required for Emacs 19.28 and earlier. +(defun eldoc-pre-command-refresh-echo-area () + (and eldoc-last-message + (if (eldoc-display-message-no-interference-p) + (eldoc-message eldoc-last-message) + (setq eldoc-last-message nil)))) + +;; Decide whether now is a good time to display a message. +(defun eldoc-display-message-p () + (and (eldoc-display-message-no-interference-p) + ;; If this-command is non-nil while running via an idle + ;; timer, we're still in the middle of executing a command, + ;; e.g. a query-replace where it would be annoying to + ;; overwrite the echo area. + (and (not this-command) + (symbolp last-command) + (intern-soft (symbol-name last-command) + eldoc-message-commands)))) + +;; Check various conditions about the current environment that might make +;; it undesirable to print eldoc messages right this instant. +(defun eldoc-display-message-no-interference-p () + (and eldoc-mode + (not executing-kbd-macro) + (not (and (boundp 'edebug-active) edebug-active)) + ;; Having this mode operate in an active minibuffer/echo area causes + ;; interference with what's going on there. + (not cursor-in-echo-area) + (not (eq (selected-window) (minibuffer-window))))) ;;;###autoload -(defun eldoc-print-fnsym-args (&optional symbol) - "*Show the defined parameters for the function near point. -For the function at the beginning of the sexp which point is within, show -the defined parameters for the function in the echo area. -This information is extracted directly from the function or macro if it is -in pure lisp. -If the emacs function is a subr, the parameters are obtained from the -documentation string if possible." - (interactive) - (let ((sym (or symbol (eldoc-fnsym-in-current-sexp))) - (printit t) - (args nil)) - (cond ((not (and (symbolp sym) - (fboundp sym)))) - ((eq sym (car eldoc-last-data)) - (setq printit nil) - (setq args (cdr eldoc-last-data))) - ((subrp (eldoc-symbol-function sym)) - (setq args (eldoc-function-argstring-from-docstring sym)) - (setcdr eldoc-last-data args)) +(defvar eldoc-documentation-function nil + "If non-nil, function to call to return doc string. +The function of no args should return a one-line string for displaying +doc about a function etc. appropriate to the context around point. +It should return nil if there's no doc appropriate for the context. +Typically doc is returned if point is on a function-like name or in its +arg list. + +This variable is expected to be made buffer-local by modes (other than +Emacs Lisp mode) that support Eldoc.") + +(defun eldoc-print-current-symbol-info () + (condition-case err + (and (eldoc-display-message-p) + (if eldoc-documentation-function + (eldoc-message (funcall eldoc-documentation-function)) + (let* ((current-symbol (eldoc-current-symbol)) + (current-fnsym (eldoc-fnsym-in-current-sexp)) + (doc (cond + ((eq current-symbol current-fnsym) + (or (eldoc-get-fnsym-args-string current-fnsym) + (eldoc-get-var-docstring current-symbol))) + (t + (or (eldoc-get-var-docstring current-symbol) + (eldoc-get-fnsym-args-string current-fnsym)))))) + (eldoc-message doc)))) + ;; This is run from post-command-hook or some idle timer thing, + ;; so we need to be careful that errors aren't ignored. + (error (message "eldoc error: %s" err)))) + +;; Return a string containing the function parameter list, or 1-line +;; docstring if function is a subr and no arglist is obtainable from the +;; docstring or elsewhere. +(defun eldoc-get-fnsym-args-string (sym) + (let ((args nil) + (doc nil)) + (cond ((not (and sym (symbolp sym) (fboundp sym)))) + ((and (eq sym (aref eldoc-last-data 0)) + (eq 'function (aref eldoc-last-data 2))) + (setq doc (aref eldoc-last-data 1))) + ((setq doc (help-split-fundoc (documentation sym t) sym)) + (setq args (car doc)) + (string-match "\\`[^ )]* ?" args) + (setq args (concat "(" (substring args (match-end 0))))) (t - (setq args (eldoc-function-argstring sym)) - (setcdr eldoc-last-data args))) - (and args - printit - (eldoc-message "%s: %s" sym args)))) + (setq args (eldoc-function-argstring sym)))) + (cond (args + (setq doc (eldoc-docstring-format-sym-doc sym args)) + (eldoc-last-data-store sym doc 'function))) + doc)) + +;; Return a string containing a brief (one-line) documentation string for +;; the variable. +(defun eldoc-get-var-docstring (sym) + (when sym + (cond ((and (eq sym (aref eldoc-last-data 0)) + (eq 'variable (aref eldoc-last-data 2))) + (aref eldoc-last-data 1)) + (t + (let ((doc (documentation-property sym 'variable-documentation t))) + (cond (doc + (setq doc (eldoc-docstring-format-sym-doc + sym (eldoc-docstring-first-line doc))) + (eldoc-last-data-store sym doc 'variable))) + doc))))) + +(defun eldoc-last-data-store (symbol doc type) + (aset eldoc-last-data 0 symbol) + (aset eldoc-last-data 1 doc) + (aset eldoc-last-data 2 type)) + +;; Note that any leading `*' in the docstring (which indicates the variable +;; is a user option) is removed. +(defun eldoc-docstring-first-line (doc) + (and (stringp doc) + (substitute-command-keys + (save-match-data + (let ((start (if (string-match "^\\*" doc) (match-end 0) 0))) + (cond ((string-match "\n" doc) + (substring doc start (match-beginning 0))) + ((zerop start) doc) + (t (substring doc start)))))))) + +;; If the entire line cannot fit in the echo area, the symbol name may be +;; truncated or eliminated entirely from the output to make room for the +;; description. +(defun eldoc-docstring-format-sym-doc (sym doc) + (save-match-data + (let* ((name (symbol-name sym)) + (ea-multi eldoc-echo-area-use-multiline-p) + ;; Subtract 1 from window width since emacs will not write + ;; any chars to the last column, or in later versions, will + ;; cause a wraparound and resize of the echo area. + (ea-width (1- (window-width (minibuffer-window)))) + (strip (- (+ (length name) (length ": ") (length doc)) ea-width))) + (cond ((or (<= strip 0) + (eq ea-multi t) + (and ea-multi (> (length doc) ea-width))) + (format "%s: %s" sym doc)) + ((> (length doc) ea-width) + (substring (format "%s" doc) 0 ea-width)) + ((>= strip (length name)) + (format "%s" doc)) + (t + ;; Show the end of the partial symbol name, rather + ;; than the beginning, since the former is more likely + ;; to be unique given package namespace conventions. + (setq name (substring name strip)) + (format "%s: %s" name doc)))))) + (defun eldoc-fnsym-in-current-sexp () - (let* ((p (point)) - (sym (progn - (while (and (eldoc-forward-sexp-safe -1) - (> (point) (point-min)))) - (cond ((or (= (point) (point-min)) - (memq (or (char-after (point)) 0) - '(?\( ?\")) - ;; If we hit a quotation mark before a paren, we - ;; are inside a specific string, not a list of - ;; symbols. - (eq (or (char-after (1- (point))) 0) ?\")) - nil) - (t (condition-case nil - (read (current-buffer)) - (error nil))))))) - (goto-char p) - (and (symbolp sym) - sym))) + (let ((p (point))) + (eldoc-beginning-of-sexp) + (prog1 + ;; Don't do anything if current word is inside a string. + (if (= (or (char-after (1- (point))) 0) ?\") + nil + (eldoc-current-symbol)) + (goto-char p)))) + +(defun eldoc-beginning-of-sexp () + (let ((parse-sexp-ignore-comments t)) + (condition-case err + (while (progn + (forward-sexp -1) + (or (= (char-before) ?\") + (> (point) (point-min))))) + (error nil)))) + +;; returns nil unless current word is an interned symbol. +(defun eldoc-current-symbol () + (let ((c (char-after (point)))) + (and c + (memq (char-syntax c) '(?w ?_)) + (intern-soft (current-word))))) + +;; Do indirect function resolution if possible. +(defun eldoc-symbol-function (fsym) + (let ((defn (and (fboundp fsym) + (symbol-function fsym)))) + (and (symbolp defn) + (condition-case err + (setq defn (indirect-function fsym)) + (error (setq defn nil)))) + defn)) (defun eldoc-function-argstring (fn) - (let* ((prelim-def (eldoc-symbol-function fn)) - (def (if (eq (car-safe prelim-def) 'macro) - (cdr prelim-def) - prelim-def)) - (arglist (cond ((null def) nil) - ((byte-code-function-p def) - (if (fboundp 'compiled-function-arglist) - (funcall 'compiled-function-arglist def) - (aref def 0))) - ((eq (car-safe def) 'lambda) - (nth 1 def)) - (t t)))) - (eldoc-function-argstring-format arglist))) - -(defun eldoc-function-argstring-from-docstring (fn) - (let ((docstring (documentation fn 'raw)) - (doc nil) - (doclist nil) - (end nil)) - (save-match-data - (cond - ;; Try first searching for args starting with symbol name. - ;; This is to avoid matching parenthetical remarks in e.g. sit-for. - ((string-match (format "^(%s[^\n)]*)$" fn) docstring) - ;; end does not include trailing ")" sequence. - (setq end (- (match-end 0) 1)) - (if (string-match " +" docstring (match-beginning 0)) - (setq doc (substring docstring (match-end 0) end)) - (setq doc ""))) - - ;; Try again not requiring this symbol name in the docstring. - ;; This will be the case when looking up aliases. - ((string-match (format "^([^\n)]+)$" fn) docstring) - ;; end does not include trailing ")" sequence. - (setq end (- (match-end 0) 1)) - (if (string-match " +" docstring (match-beginning 0)) - (setq doc (substring docstring (match-end 0) end)) - (setq doc ""))) - - ;; Emacs subr docstring style: - ;; (fn arg1 arg2 ...): description... - ((string-match "^([^\n)]+):" docstring) - ;; end does not include trailing "):" sequence. - (setq end (- (match-end 0) 2)) - (if (string-match " +" docstring (match-beginning 0)) - (setq doc (substring docstring (match-end 0) end)) - (setq doc ""))) - - ;; XEmacs subr docstring style: - ;; "arguments: (arg1 arg2 ...) - ((string-match "^arguments: (\\([^\n)]+\\))" docstring) - ;; Also, skip leading paren, but the first word is actually an - ;; argument, not the function name. - (setq doc (substring docstring - (match-beginning 1) - (match-end 1)))) - - ;; This finds the argstring for `condition-case'. - ;; I don't know if there are any others with the same pattern. - ((string-match (format "^Usage looks like \\((%s[^\n)]*)\\)\\.$" fn) - docstring) - ;; end does not include trailing ")" sequence. - (setq end (- (match-end 1) 1)) - (if (string-match " +" docstring (match-beginning 1)) - (setq doc (substring docstring (match-end 0) end)) - (setq doc ""))) - - ;; This finds the argstring for `setq-default'. - ;; I don't know if there are any others with the same pattern. - ((string-match (format "^[ \t]+\\((%s[^\n)]*)\\)$" fn) docstring) - ;; end does not include trailing ")" sequence. - (setq end (- (match-end 1) 1)) - (if (string-match " +" docstring (match-beginning 1)) - (setq doc (substring docstring (match-end 0) end)) - (setq doc "")))) - - (cond ((not (stringp doc)) - nil) - ((string-match "&" doc) - (let ((p 0) - (l (length doc))) - (while (< p l) - (cond ((string-match "[ \t\n]+" doc p) - (setq doclist - (cons (substring doc p (match-beginning 0)) - doclist)) - (setq p (match-end 0))) - (t - (setq doclist (cons (substring doc p) doclist)) - (setq p l)))) - (eldoc-function-argstring-format (nreverse doclist)))) - (t - (concat "(" (funcall eldoc-argument-case doc) ")")))))) + (eldoc-function-argstring-format (help-function-arglist fn))) (defun eldoc-function-argstring-format (arglist) (cond ((not (listp arglist)) @@ -412,37 +401,45 @@ documentation string if possible." (concat "(" (mapconcat 'identity arglist " ") ")")) -;; forward-sexp calls scan-sexps, which returns an error if it hits the -;; beginning or end of the sexp. This returns nil instead. -(defun eldoc-forward-sexp-safe (&optional count) - "Move forward across one balanced expression (sexp). -With argument, do it that many times. Negative arg -COUNT means -move backward across COUNT balanced expressions. -Return distance in buffer moved, or nil." - (or count (setq count 1)) - (condition-case err - (- (- (point) (progn - (let ((parse-sexp-ignore-comments t)) - (forward-sexp count)) - (point)))) - (error nil))) - -;; Do indirect function resolution if possible. -(defun eldoc-symbol-function (fsym) - (let ((defn (and (fboundp fsym) - (symbol-function fsym)))) - (and (symbolp defn) - (condition-case err - (setq defn (indirect-function fsym)) - (error (setq defn nil)))) - defn)) +;; When point is in a sexp, the function args are not reprinted in the echo +;; area after every possible interactive command because some of them print +;; their own messages in the echo area; the eldoc functions would instantly +;; overwrite them unless it is more restrained. +;; These functions do display-command table management. + +(defun eldoc-add-command (&rest cmds) + (dolist (name cmds) + (and (symbolp name) + (setq name (symbol-name name))) + (set (intern name eldoc-message-commands) t))) + +(defun eldoc-add-command-completions (&rest names) + (dolist (name names) + (apply 'eldoc-add-command (all-completions name obarray 'commandp)))) + +(defun eldoc-remove-command (&rest cmds) + (dolist (name cmds) + (and (symbolp name) + (setq name (symbol-name name))) + (unintern name eldoc-message-commands))) + +(defun eldoc-remove-command-completions (&rest names) + (dolist (name names) + (apply 'eldoc-remove-command + (all-completions name eldoc-message-commands)))) -(defun eldoc-current-symbol () - (let ((c (char-after (point)))) - (and c - (memq (char-syntax c) '(?w ?_)) - (intern-soft (current-word))))) + +;; Prime the command list. +(eldoc-add-command-completions + "backward-" "beginning-of-" "move-beginning-of-" "delete-other-windows" + "delete-window" + "end-of-" "move-end-of-" "exchange-point-and-mark" "forward-" + "indent-for-tab-command" "goto-" "mark-page" "mark-paragraph" + "mouse-set-point" "move-" "pop-global-mark" "next-" "other-window" + "previous-" "recenter" "scroll-" "self-insert-command" + "split-window-" "up-list" "down-list") (provide 'eldoc) +;; arch-tag: c9a58f9d-2055-46c1-9b82-7248b71a8375 ;;; eldoc.el ends here