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Diffstat (limited to 'lisp/progmodes/which-func.el')
| -rw-r--r-- | lisp/progmodes/which-func.el | 256 |
1 files changed, 256 insertions, 0 deletions
diff --git a/lisp/progmodes/which-func.el b/lisp/progmodes/which-func.el new file mode 100644 index 00000000000..4b1dfca6f5b --- /dev/null +++ b/lisp/progmodes/which-func.el @@ -0,0 +1,256 @@ +;;; which-func.el --- print current function in mode line + +;; Copyright (C) 1994, 1997, 1998, 2001, 2003 Free Software Foundation, Inc. + +;; Author: Alex Rezinsky <alexr@msil.sps.mot.com> +;; (doesn't seem to be responsive any more) +;; Keywords: mode-line, imenu, tools + +;; 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 2, 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; see the file COPYING. If not, write to the +;; Free Software Foundation, Inc., 59 Temple Place - Suite 330, +;; Boston, MA 02111-1307, USA. + +;;; Commentary: + +;; This package prints name of function where your current point is +;; located in mode line. It assumes that you work with imenu package +;; and imenu--index-alist is up to date. + +;; KNOWN BUGS +;; ---------- +;; Really this package shows not "function where the current point is +;; located now", but "nearest function which defined above the current +;; point". So if your current point is located after end of function +;; FOO but before begin of function BAR, FOO will be displayed in mode +;; line. +;; - if two windows display the same buffer, both windows +;; show the same `which-func' information. + +;; TODO LIST +;; --------- +;; 1. Dependence on imenu package should be removed. Separate +;; function determination mechanism should be used to determine the end +;; of a function as well as the beginning of a function. +;; 2. This package should be realized with the help of overlay +;; properties instead of imenu--index-alist variable. + +;;; History: + +;; THANKS TO +;; --------- +;; Per Abrahamsen <abraham@iesd.auc.dk> +;; Some ideas (inserting in mode-line, using of post-command hook +;; and toggling this mode) have been borrowed from his package +;; column.el +;; Peter Eisenhauer <pipe@fzi.de> +;; Bug fixing in case nested indexes. +;; Terry Tateyama <ttt@ursa0.cs.utah.edu> +;; Suggestion to use find-file-hook for first imenu +;; index building. + +;;; Code: + +;; Variables for customization +;; --------------------------- +;; +(defvar which-func-unknown "???" + "String to display in the mode line when current function is unknown.") + +(defgroup which-func nil + "Mode to display the current function name in the modeline." + :group 'tools + :version "20.3") + +(defcustom which-func-modes + '(emacs-lisp-mode c-mode c++-mode perl-mode cperl-mode makefile-mode + sh-mode fortran-mode f90-mode) + "List of major modes for which Which Function mode should be used. +For other modes it is disabled. If this is equal to t, +then Which Function mode is enabled in any major mode that supports it." + :group 'which-func + :type '(choice (const :tag "All modes" t) + (repeat (symbol :tag "Major mode")))) + +(defcustom which-func-non-auto-modes nil + "List of major modes where Which Function mode is inactive till Imenu is used. +This means that Which Function mode won't really do anything +until you use Imenu, in these modes. Note that files +larger than `which-func-maxout' behave in this way too; +Which Function mode doesn't do anything until you use Imenu." + :group 'which-func + :type '(repeat (symbol :tag "Major mode"))) + +(defcustom which-func-maxout 500000 + "Don't automatically compute the Imenu menu if buffer is this big or bigger. +Zero means compute the Imenu menu regardless of size." + :group 'which-func + :type 'integer) + +(defcustom which-func-format '("[" which-func-current "]") + "Format for displaying the function in the mode line." + :group 'which-func + :type 'sexp) +;;;###autoload (put 'which-func-format 'risky-local-variable t) + +(defvar which-func-cleanup-function nil + "Function to transform a string before displaying it in the mode line. +The function is called with one argument, the string to display. +Its return value is displayed in the modeline. +If nil, no function is called. The default value is nil. + +This feature can be useful if Imenu is set up to make more +detailed entries (e.g., containing the argument list of a function), +and you want to simplify them for the mode line +\(e.g., removing the parameter list to just have the function name.)") + +;;; Code, nothing to customize below here +;;; ------------------------------------- +;;; +(require 'imenu) + +(defvar which-func-table (make-hash-table :test 'eq :weakness 'key)) + +(defconst which-func-current + '(:eval (gethash (selected-window) which-func-table which-func-unknown))) +;;;###autoload (put 'which-func-current 'risky-local-variable t) + +(defvar which-func-mode nil + "Non-nil means display current function name in mode line. +This makes a difference only if `which-function-mode' is non-nil.") +(make-variable-buffer-local 'which-func-mode) +;;(put 'which-func-mode 'permanent-local t) + +(add-hook 'find-file-hook 'which-func-ff-hook t) + +(defun which-func-ff-hook () + "File find hook for Which Function mode. +It creates the Imenu index for the buffer, if necessary." + (setq which-func-mode + (and which-function-mode + (or (eq which-func-modes t) + (member major-mode which-func-modes)))) + + (condition-case nil + (if (and which-func-mode + (not (member major-mode which-func-non-auto-modes)) + (or (null which-func-maxout) + (< buffer-saved-size which-func-maxout) + (= which-func-maxout 0))) + (setq imenu--index-alist + (save-excursion (funcall imenu-create-index-function)))) + (error + (setq which-func-mode nil)))) + +(defun which-func-update () + ;; "Update the Which-Function mode display for all windows." + ;; (walk-windows 'which-func-update-1 nil 'visible)) + (which-func-update-1 (selected-window))) + +(defun which-func-update-1 (window) + "Update the Which-Function mode display for window WINDOW." + (with-selected-window window + (when which-func-mode + (condition-case info + (let ((current (which-function))) + (unless (equal current (gethash window which-func-table)) + (puthash window current which-func-table) + (force-mode-line-update))) + (error + (which-func-mode -1) + (error "Error in which-func-update: %s" info)))))) + +;;;###autoload +(defalias 'which-func-mode 'which-function-mode) + +(defvar which-func-update-timer nil) + +;; This is the name people would normally expect. +;;;###autoload +(define-minor-mode which-function-mode + "Toggle Which Function mode, globally. +When Which Function mode is enabled, the current function name is +continuously displayed in the mode line, in certain major modes. + +With prefix ARG, turn Which Function mode on iff arg is positive, +and off otherwise." + :global t :group 'which-func + (if which-function-mode + ;;Turn it on + (progn + (setq which-func-update-timer + (run-with-idle-timer idle-update-delay t 'which-func-update)) + (dolist (buf (buffer-list)) + (with-current-buffer buf + (setq which-func-mode + (or (eq which-func-modes t) + (member major-mode which-func-modes)))))) + ;; Turn it off + (cancel-timer which-func-update-timer) + (setq which-func-update-timer nil) + (dolist (buf (buffer-list)) + (with-current-buffer buf (setq which-func-mode nil))))) + +(defvar which-function-imenu-failed nil + "Locally t in a buffer if `imenu--make-index-alist' found nothing there.") + +(defun which-function () + "Return current function name based on point. +Uses `imenu--index-alist' or `add-log-current-defun-function'. +If no function name is found, return nil." + (let (name) + ;; If Imenu is loaded, try to make an index alist with it. + (when (and (boundp 'imenu--index-alist) (null imenu--index-alist) + (null which-function-imenu-failed)) + (imenu--make-index-alist) + (unless imenu--index-alist + (make-local-variable 'which-function-imenu-failed) + (setq which-function-imenu-failed t))) + ;; If we have an index alist, use it. + (when (and (boundp 'imenu--index-alist) imenu--index-alist) + (let ((alist imenu--index-alist) + (minoffset (point-max)) + offset elem pair mark) + (while alist + (setq elem (car-safe alist) + alist (cdr-safe alist)) + ;; Elements of alist are either ("name" . marker), or + ;; ("submenu" ("name" . marker) ... ). + (unless (listp (cdr elem)) + (setq elem (list elem))) + (while elem + (setq pair (car elem) + elem (cdr elem)) + (and (consp pair) + (number-or-marker-p (setq mark (cdr pair))) + (if (>= (setq offset (- (point) mark)) 0) + (if (< offset minoffset) ; find the closest item + (setq minoffset offset + name (car pair))) + ;; Entries in order, so can skip all those after point. + (setq elem nil))))))) + ;; Try using add-log support. + (when (and (null name) (boundp 'add-log-current-defun-function) + add-log-current-defun-function) + (setq name (funcall add-log-current-defun-function))) + ;; Filter the name if requested. + (when name + (if which-func-cleanup-function + (funcall which-func-cleanup-function name) + name)))) + +(provide 'which-func) + +;;; which-func.el ends here |