;;; eldoc.el --- show function arglist or variable docstring in echo area
;; Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
-;; 2005, 2006, 2007 Free Software Foundation, Inc.
+;; 2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
;; Author: Noah Friedman <friedman@splode.com>
;; Maintainer: friedman@splode.com
;; This file is part of GNU Emacs.
-;; GNU Emacs 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.
+;; 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
;; GNU General Public License for more details.
;; You should have received a copy of the GNU General Public License
-;; 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.
+;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
;;; Commentary:
:group 'extensions)
(defcustom eldoc-idle-delay 0.50
- "*Number of seconds of idle time to wait before printing.
+ "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.
;;;###autoload
(defcustom eldoc-minor-mode-string " ElDoc"
- "*String to display in mode line when Eldoc Mode is enabled; nil for none."
+ "String to display in mode line when Eldoc Mode is enabled; nil for none."
:type '(choice string (const :tag "None" nil))
:group 'eldoc)
"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."
+returns another string is acceptable.
+
+Note that if `eldoc-documentation-function' is non-nil, this variable
+has no effect, unless the function handles it explicitly."
: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.
+ "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 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."
+truncated to make more of the arglist or documentation string visible.
+
+Note that if `eldoc-documentation-function' is non-nil, this variable
+has no effect, unless the function handles it explicitly."
: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)
+(defface eldoc-highlight-function-argument
+ '((t (:inherit bold)))
+ "Face used for the argument at point in a function's argument list.
+Note that if `eldoc-documentation-function' is non-nil, this face
+has no effect, unless the function handles it explicitly."
+ :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.
+ "Used by `eldoc-add-command' to initialize `eldoc-message-commands' 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.
(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,
+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
+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'.")
2 - 'function if function args, 'variable if variable documentation.")
(defvar eldoc-last-message nil)
-(defvar eldoc-timer nil "eldoc's timer object.")
+(defvar eldoc-timer nil "ElDoc's timer object.")
(defvar eldoc-current-idle-delay eldoc-idle-delay
- "idle time delay currently in use by timer.
+ "Idle time delay currently in use by timer.
This is used to determine if `eldoc-idle-delay' is changed by the user.")
\f
Typically doc is returned if point is on a function-like name or in its
arg list.
+The result is used as is, so the function must explicitly handle
+the variables `eldoc-argument-case' and `eldoc-echo-area-use-multiline-p',
+and the face `eldoc-highlight-function-argument', if they are to have any
+effect.
+
This variable is expected to be made buffer-local by modes (other than
Emacs Lisp mode) that support Eldoc.")
;; 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 argument-index)
- (let ((args nil)
- (doc nil))
+(defun eldoc-get-fnsym-args-string (sym &optional index)
+ "Return a string containing the parameter list of the function SYM.
+If SYM is a subr and no arglist is obtainable from the docstring
+or elsewhere, return a 1-line docstring. Calls the functions
+`eldoc-function-argstring-format' and
+`eldoc-highlight-function-argument' to format the result. The
+former calls `eldoc-argument-case'; the latter gives the
+function name `font-lock-function-name-face', and optionally
+highlights argument number INDEX."
+ (let (args doc)
(cond ((not (and sym (symbolp sym) (fboundp sym))))
- ((and (eq sym (aref eldoc-last-data 0))
- (eq 'function (aref eldoc-last-data 2)))
- (setq args (aref eldoc-last-data 1)))
+ ((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))
+ ;; Remove any enclosing (), since e-function-argstring adds them.
(string-match "\\`[^ )]* ?" args)
- (setq args (concat "(" (substring args (match-end 0))))
- (eldoc-last-data-store sym args 'function))
- (t
- (setq args (eldoc-function-argstring sym))))
- (when args
- (setq doc (eldoc-highlight-function-argument sym args argument-index)))
- doc))
-
-;; Highlight argument INDEX in ARGS list for SYM.
+ (setq args (substring args (match-end 0)))
+ (if (string-match ")\\'" args)
+ (setq args (substring args 0 -1))))
+ (t
+ (setq args (help-function-arglist sym))))
+ (if args
+ ;; Stringify, and store before highlighting, downcasing, etc.
+ ;; FIXME should truncate before storing.
+ (eldoc-last-data-store sym (setq args (eldoc-function-argstring args))
+ 'function)
+ (setq args doc)) ; use stored value
+ ;; Change case, highlight, truncate.
+ (if args
+ (eldoc-highlight-function-argument
+ sym (eldoc-function-argstring-format args) index))))
+
(defun eldoc-highlight-function-argument (sym args index)
+ "Highlight argument INDEX in ARGS list for function SYM.
+In the absence of INDEX, just call `eldoc-docstring-format-sym-doc'."
(let ((start nil)
(end 0)
- (argument-face 'bold))
+ (argument-face 'eldoc-highlight-function-argument))
;; Find the current argument in the argument string. We need to
;; handle `&rest' and informal `...' properly.
;;
;; (defun NAME ARGLIST [DOCSTRING] BODY...) case?
;; The problem is there is no robust way to determine if
;; the current argument is indeed a docstring.
- (while (>= index 1)
+ (while (and index (>= index 1))
(if (string-match "[^ ()]+" args end)
(progn
(setq start (match-beginning 0)
(and (stringp doc)
(substitute-command-keys
(save-match-data
- (let ((start (if (string-match "^\\*" doc) (match-end 0) 0)))
+ ;; Don't use "^" in the regexp below since it may match
+ ;; anywhere in the doc-string.
+ (let ((start (if (string-match "\\`\\*" doc) (match-end 0) 0)))
(cond ((string-match "\n" doc)
(substring doc start (match-beginning 0)))
((zerop start) doc)
(error (setq defn nil))))
defn))
-(defun eldoc-function-argstring (fn)
- (eldoc-function-argstring-format (help-function-arglist fn)))
-
-(defun eldoc-function-argstring-format (arglist)
- (cond ((not (listp arglist))
- (setq arglist nil))
- ((symbolp (car arglist))
- (setq arglist
- (mapcar (function (lambda (s)
- (if (memq s '(&optional &rest))
- (symbol-name s)
- (funcall eldoc-argument-case
- (symbol-name s)))))
- arglist)))
- ((stringp (car arglist))
- (setq arglist
- (mapcar (function (lambda (s)
- (if (member s '("&optional" "&rest"))
- s
- (funcall eldoc-argument-case s))))
- arglist))))
- (concat "(" (mapconcat 'identity arglist " ") ")"))
+(defun eldoc-function-argstring (arglist)
+ "Return ARGLIST as a string enclosed by ().
+ARGLIST is either a string, or a list of strings or symbols."
+ (cond ((stringp arglist))
+ ((not (listp arglist))
+ (setq arglist nil))
+ ((symbolp (car arglist))
+ (setq arglist
+ (mapconcat (lambda (s) (symbol-name s))
+ arglist " ")))
+ ((stringp (car arglist))
+ (setq arglist
+ (mapconcat (lambda (s) s)
+ arglist " "))))
+ (if arglist
+ (format "(%s)" arglist)))
+
+(defun eldoc-function-argstring-format (argstring)
+ "Apply `eldoc-argument-case' to each word in ARGSTRING.
+The words \"&rest\", \"&optional\" are returned unchanged."
+ (mapconcat (lambda (s)
+ (if (member s '("&optional" "&rest"))
+ s
+ (funcall eldoc-argument-case s)))
+ (split-string argstring "[][ ()]+" t) " "))
\f
;; When point is in a sexp, the function args are not reprinted in the echo