;;; eldoc.el --- show function arglist or variable docstring in echo area
-;; Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc.
+;; Copyright (C) 1996, 97, 98, 99, 2000, 2003 Free Software Foundation, Inc.
;; Author: Noah Friedman <friedman@splode.com>
;; Maintainer: friedman@splode.com
;; Keywords: extensions
;; Created: 1995-10-06
-;; $Id: eldoc.el,v 1.15 1998/09/19 02:15:26 friedman Exp $
+;; $Id: eldoc.el,v 1.26 2003/09/01 15:45:22 miles Exp $
;; This file is part of GNU Emacs.
;; 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)
+;; Major modes for other languages may use Eldoc by defining an
+;; appropriate function as the buffer-local value of
+;; `eldoc-print-current-symbol-info-function'.
+
;;; Code:
-;; Use idle timers if available in the version of emacs running.
-;; Please don't change this to use `require'; this package works as-is in
-;; XEmacs (which doesn't have timer.el as of 19.14), and I would like to
-;; maintain compatibility with that since I must use it sometimes. --Noah
-(or (featurep 'timer)
- (load "timer" t))
+(require 'help-fns) ;For fundoc-usage handling functions.
(defgroup eldoc nil
"Show function arglist or variable docstring in echo area."
+ :group 'lisp
:group 'extensions)
-;;;###autoload
-(defcustom 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. If the emacs function is a subr, the parameters are obtained
-from the documentation string if possible.
-
-If point is over a documented variable, print that variable's docstring
-instead.
-
-This variable is buffer-local."
- :type 'boolean
- :group 'eldoc)
-(make-variable-buffer-local 'eldoc-mode)
-
(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
:type 'number
:group 'eldoc)
+;;;###autoload
(defcustom eldoc-minor-mode-string " ElDoc"
- "*String to display in mode line when Eldoc Mode is enabled."
- :type 'string
+ "*String to display in mode line when Eldoc Mode is enabled; nil for none."
+ :type '(choice string (const :tag "None" nil))
:group 'eldoc)
-;; 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)))))
-
(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."
- :type '(radio function
- (function-item upcase)
- (function-item downcase))
+ :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.
+;;; No user options below here.
;; 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,
(defvar eldoc-last-data (make-vector 3 nil))
(defvar eldoc-last-message nil)
-;; Idle timers are supported in Emacs 19.31 and later.
-(defvar eldoc-use-idle-timer-p (fboundp 'run-with-idle-timer))
-
-;; eldoc's timer object, if using idle timers
+;; eldoc's timer object.
(defvar eldoc-timer nil)
;; idle time delay currently in use by timer.
\f
;;;###autoload
-(defun eldoc-mode (&optional prefix)
- "*Enable or disable eldoc mode.
-See documentation for the variable of the same name for more details.
-
-If called interactively with no prefix argument, toggle current condition
-of the mode.
-If called with a positive or negative prefix argument, enable or disable
-the mode, respectively."
- (interactive "P")
+(define-minor-mode eldoc-mode
+ "Toggle ElDoc mode on or off.
+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. If the emacs function is a subr, the parameters are obtained
+from the documentation string if possible.
+
+If point is over a documented variable, print that variable's docstring
+instead.
+
+With prefix ARG, turn ElDoc mode on if and only if ARG is positive."
+ nil eldoc-minor-mode-string nil
(setq eldoc-last-message nil)
- (cond (eldoc-use-idle-timer-p
- (add-hook 'post-command-hook 'eldoc-schedule-timer)
- (add-hook 'pre-command-hook 'eldoc-pre-command-refresh-echo-area))
- (t
- ;; Use post-command-idle-hook if defined, otherwise use
- ;; post-command-hook. The former is only proper to use in Emacs
- ;; 19.30; that is the first version in which it appeared, but it
- ;; was obsolesced by idle timers in Emacs 19.31.
- (add-hook (if (boundp 'post-command-idle-hook)
- 'post-command-idle-hook
- 'post-command-hook)
- 'eldoc-print-current-symbol-info)
- ;; quick and dirty hack for seeing if this is XEmacs
- (and (fboundp 'display-message)
- (add-hook 'pre-command-hook
- 'eldoc-pre-command-refresh-echo-area))))
- (setq eldoc-mode (if prefix
- (>= (prefix-numeric-value prefix) 0)
- (not eldoc-mode)))
- (and (interactive-p)
- (if eldoc-mode
- (message "eldoc-mode is enabled")
- (message "eldoc-mode is disabled")))
- eldoc-mode)
+ (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 ()
(defun eldoc-message (&rest args)
(let ((omessage eldoc-last-message))
- (cond ((eq (car args) eldoc-last-message))
- ((or (null args)
- (null (car args)))
- (setq eldoc-last-message 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))
- (setq eldoc-last-message (car args)))
- (t
- (setq eldoc-last-message (apply 'format args))))
+ (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.
- (cond ((fboundp 'display-message)
- ;; XEmacs 19.13 way of preventing log messages.
- (cond (eldoc-last-message
- (display-message 'no-log eldoc-last-message))
- (omessage
- (clear-message 'no-log))))
- (t
- ;; Emacs way of preventing log messages.
- (let ((message-log-max nil))
- (cond (eldoc-last-message
- (message "%s" eldoc-last-message))
- (omessage
- (message nil)))))))
+ ;; 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
;; Decide whether now is a good time to display a message.
(defun eldoc-display-message-p ()
(and (eldoc-display-message-no-interference-p)
- (cond (eldoc-use-idle-timer-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)))
- (t
- ;; If we don't have idle timers, this function is
- ;; running on post-command-hook directly; that means the
- ;; user's last command is still on `this-command', and we
- ;; must wait briefly for input to see whether to do display.
- (and (symbolp this-command)
- (intern-soft (symbol-name this-command)
- eldoc-message-commands)
- (sit-for eldoc-idle-delay))))))
-
+ ;; 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)))))
\f
+(defvar eldoc-print-current-symbol-info-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 ()
- (and (eldoc-display-message-p)
- (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))))
+ (condition-case err
+ (and (eldoc-display-message-p)
+ (if eldoc-print-current-symbol-info-function
+ (eldoc-message (funcall eldoc-print-current-symbol-info-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
(defun eldoc-get-fnsym-args-string (sym)
(let ((args nil)
(doc nil))
- (cond ((not (and sym
- (symbolp sym)
- (fboundp sym))))
+ (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)))
- ((subrp (eldoc-symbol-function sym))
- (setq args (or (eldoc-function-argstring-from-docstring sym)
- (eldoc-docstring-first-line (documentation sym t)))))
+ ((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))))
(cond (args
;; Return a string containing a brief (one-line) documentation string for
;; the variable.
(defun eldoc-get-var-docstring (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))))
+ (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)
(defun eldoc-docstring-format-sym-doc (sym doc)
(save-match-data
(let* ((name (symbol-name sym))
- (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)
- (format "%s" doc))
- (t
- ;;(setq name (substring name 0 (- len strip)))
- ;;
- ;; 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)))))
+ (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
- (format "%s: %s" sym doc))))))
+ ;; 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))))))
\f
(defun eldoc-fnsym-in-current-sexp ()
(condition-case err
(while (progn
(forward-sexp -1)
- (or (= (or (char-after (1- (point)))) ?\")
+ (or (= (char-before) ?\")
(> (point) (point-min)))))
(error 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)))
+ (eldoc-function-argstring-format (help-function-arglist fn)))
(defun eldoc-function-argstring-format (arglist)
(cond ((not (listp arglist))
arglist))))
(concat "(" (mapconcat 'identity arglist " ") ")"))
-\f
-;; Alist of predicate/action pairs.
-;; Each member of the list is a sublist consisting of a predicate function
-;; used to determine if the arglist for a function can be found using a
-;; certain pattern, and a function which returns the actual arglist from
-;; that docstring.
-;;
-;; The order in this table is significant, since later predicates may be
-;; more general than earlier ones.
-;;
-;; Compiler note for Emacs/XEmacs versions which support dynamic loading:
-;; these functions will be compiled to bytecode, but can't be lazy-loaded
-;; even if you set byte-compile-dynamic; to do that would require making
-;; them named top-level defuns, which is not particularly desirable either.
-(defvar eldoc-function-argstring-from-docstring-method-table
- (list
- ;; Try first searching for args starting with symbol name.
- ;; This is to avoid matching parenthetical remarks in e.g. sit-for.
- (list (function (lambda (doc fn)
- (string-match (format "^(%s[^\n)]*)$" fn) doc)))
- (function (lambda (doc)
- ;; end does not include trailing ")" sequence.
- (let ((end (- (match-end 0) 1)))
- (if (string-match " +" doc (match-beginning 0))
- (substring doc (match-end 0) end)
- "")))))
-
- ;; Try again not requiring this symbol name in the docstring.
- ;; This will be the case when looking up aliases.
- (list (function (lambda (doc fn)
- ;; save-restriction has a pathological docstring in
- ;; Emacs/XEmacs 19.
- (and (not (eq fn 'save-restriction))
- (string-match "^([^\n)]+)$" doc))))
- (function (lambda (doc)
- ;; end does not include trailing ")" sequence.
- (let ((end (- (match-end 0) 1)))
- (and (string-match " +" doc (match-beginning 0))
- (substring doc (match-end 0) end))))))
-
- ;; Emacs subr docstring style:
- ;; (fn arg1 arg2 ...): description...
- (list (function (lambda (doc fn)
- (string-match "^([^\n)]+):" doc)))
- (function (lambda (doc)
- ;; end does not include trailing "):" sequence.
- (let ((end (- (match-end 0) 2)))
- (and (string-match " +" doc (match-beginning 0))
- (substring doc (match-end 0) end))))))
-
- ;; XEmacs subr docstring style:
- ;; "arguments: (arg1 arg2 ...)
- (list (function (lambda (doc fn)
- (string-match "^arguments: (\\([^\n)]+\\))" doc)))
- (function (lambda (doc)
- ;; also skip leading paren, but the first word is
- ;; actually an argument, not the function name.
- (substring doc (match-beginning 1) (match-end 1)))))
-
- ;; This finds the argstring for `condition-case'. Any others?
- (list (function (lambda (doc fn)
- (string-match
- (format "^Usage looks like \\((%s[^\n)]*)\\)\\.$" fn)
- doc)))
- (function (lambda (doc)
- ;; end does not include trailing ")" sequence.
- (let ((end (- (match-end 1) 1)))
- (and (string-match " +" doc (match-beginning 1))
- (substring doc (match-end 0) end))))))
-
- ;; This finds the argstring for `setq-default'. Any others?
- (list (function (lambda (doc fn)
- (string-match (format "^[ \t]+\\((%s[^\n)]*)\\)$" fn)
- doc)))
- (function (lambda (doc)
- ;; end does not include trailing ")" sequence.
- (let ((end (- (match-end 1) 1)))
- (and (string-match " +" doc (match-beginning 1))
- (substring doc (match-end 0) end))))))
-
- ;; This finds the argstring for `start-process'. Any others?
- (list (function (lambda (doc fn)
- (string-match "^Args are +\\([^\n]+\\)$" doc)))
- (function (lambda (doc)
- (substring doc (match-beginning 1) (match-end 1)))))
-
- ;; These common subrs don't have arglists in their docstrings. So cheat.
- (list (function (lambda (doc fn)
- (memq fn '(and or list + -))))
- (function (lambda (doc)
- ;; The value nil is a placeholder; otherwise, the
- ;; following string may be compiled as a docstring,
- ;; and not a return value for the function.
- ;; In interpreted lisp form they are
- ;; indistinguishable; it only matters for compiled
- ;; forms.
- nil
- "&rest args")))
- ))
-
-(defun eldoc-function-argstring-from-docstring (fn)
- (let ((docstring (documentation fn 'raw))
- (table eldoc-function-argstring-from-docstring-method-table)
- (doc nil)
- (doclist nil))
- (save-match-data
- (while table
- (cond ((funcall (car (car table)) docstring fn)
- (setq doc (funcall (car (cdr (car table))) docstring))
- (setq table nil))
- (t
- (setq table (cdr table)))))
-
- (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) ")"))))))
-
\f
;; 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
(defun eldoc-add-command-completions (&rest names)
(while names
- (apply 'eldoc-add-command
- (all-completions (car names) obarray 'fboundp))
- (setq names (cdr names))))
+ (apply 'eldoc-add-command
+ (all-completions (car names) obarray 'fboundp))
+ (setq names (cdr names))))
(defun eldoc-remove-command (&rest cmds)
(let (name)
(and (symbolp name)
(setq name (symbol-name name)))
- (if (fboundp 'unintern)
- (unintern name eldoc-message-commands)
- (let ((s (intern-soft name eldoc-message-commands)))
- (and s
- (makunbound s)))))))
+ (unintern name eldoc-message-commands))))
(defun eldoc-remove-command-completions (&rest names)
(while names
(provide 'eldoc)
+;;; arch-tag: c9a58f9d-2055-46c1-9b82-7248b71a8375
;;; eldoc.el ends here