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emacs/lisp/options.el
1993-03-22 05:42:35 +00:00

139 lines
4.6 KiB
EmacsLisp

;;; options.el --- edit Options command for Emacs.
;; Copyright (C) 1985 Free Software Foundation, Inc.
;; Maintainer: FSF
;; 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, 675 Mass Ave, Cambridge, MA 02139, USA.
;;; Commentary:
;; This code provides functions to list and edit the values of all global
;; option variables known to loaded Emacs Lisp code. There are two entry
;; points, `list-options' and `edit' options'. The latter enters a major
;; mode specifically for editing option values. Do `M-x describe-mode' in
;; that context for more details.
;;; Code:
;;;###autoload
(defun list-options ()
"Display a list of Emacs user options, with values and documentation."
(interactive)
(save-excursion
(set-buffer (get-buffer-create "*List Options*"))
(Edit-options-mode))
(with-output-to-temp-buffer "*List Options*"
(let (vars)
(mapatoms (function (lambda (sym)
(if (user-variable-p sym)
(setq vars (cons sym vars))))))
(setq vars (sort vars 'string-lessp))
(while vars
(let ((sym (car vars)))
(princ ";; ")
(prin1 sym)
(princ ":\n\t")
(prin1 (symbol-value sym))
(terpri)
(princ (substitute-command-keys
(documentation-property sym 'variable-documentation)))
(princ "\n;;\n"))
(setq vars (cdr vars))))))
;;;###autoload
(defun edit-options ()
"Edit a list of Emacs user option values.
Selects a buffer containing such a list,
in which there are commands to set the option values.
Type \\[describe-mode] in that buffer for a list of commands."
(interactive)
(list-options)
(pop-to-buffer "*List Options*"))
(defvar Edit-options-mode-map
(let ((map (make-keymap)))
(define-key map "s" 'Edit-options-set)
(define-key map "x" 'Edit-options-toggle)
(define-key map "1" 'Edit-options-t)
(define-key map "0" 'Edit-options-nil)
(define-key map "p" 'backward-paragraph)
(define-key map " " 'forward-paragraph)
(define-key map "n" 'forward-paragraph)
map)
"")
;; Edit Options mode is suitable only for specially formatted data.
(put 'Edit-options-mode 'mode-class 'special)
(defun Edit-options-mode ()
"\\<Edit-options-mode-map>\
Major mode for editing Emacs user option settings.
Special commands are:
\\[Edit-options-set] -- set variable point points at. New value read using minibuffer.
\\[Edit-options-toggle] -- toggle variable, t -> nil, nil -> t.
\\[Edit-options-t] -- set variable to t.
\\[Edit-options-nil] -- set variable to nil.
Changed values made by these commands take effect immediately.
Each variable description is a paragraph.
For convenience, the characters \\[backward-paragraph] and \\[forward-paragraph] move back and forward by paragraphs."
(kill-all-local-variables)
(set-syntax-table emacs-lisp-mode-syntax-table)
(use-local-map Edit-options-mode-map)
(make-local-variable 'paragraph-separate)
(setq paragraph-separate "[^\^@-\^?]")
(make-local-variable 'paragraph-start)
(setq paragraph-start "^\t")
(setq truncate-lines t)
(setq major-mode 'Edit-options-mode)
(setq mode-name "Options")
(run-hooks 'Edit-options-mode-hook))
(defun Edit-options-set () (interactive)
(Edit-options-modify
'(lambda (var) (eval-minibuffer (concat "New " (symbol-name var) ": ")))))
(defun Edit-options-toggle () (interactive)
(Edit-options-modify '(lambda (var) (not (symbol-value var)))))
(defun Edit-options-t () (interactive)
(Edit-options-modify '(lambda (var) t)))
(defun Edit-options-nil () (interactive)
(Edit-options-modify '(lambda (var) nil)))
(defun Edit-options-modify (modfun)
(save-excursion
(let (var pos)
(re-search-backward "^;; \\|\\`")
(forward-char 3)
(setq pos (point))
(save-restriction
(narrow-to-region pos (progn (end-of-line) (1- (point))))
(goto-char pos)
(setq var (read (current-buffer))))
(goto-char pos)
(forward-line 1)
(forward-char 1)
(save-excursion
(set var (funcall modfun var)))
(kill-sexp 1)
(prin1 (symbol-value var) (current-buffer)))))
;;; options.el ends here