lisp/obsolete/options.el

   1 ;;; options.el --- edit Options command for Emacs
   2
   3 ;; Copyright (C) 1985, 2001, 2002, 2003, 2004, 2005,
   4 ;;   2006, 2007, 2008 Free Software Foundation, Inc.
   5
   6 ;; Maintainer: FSF
   7
   8 ;; This file is part of GNU Emacs.
   9
  10 ;; GNU Emacs is free software; you can redistribute it and/or modify
  11 ;; it under the terms of the GNU General Public License as published by
  12 ;; the Free Software Foundation; either version 3, or (at your option)
  13 ;; any later version.
  14
  15 ;; GNU Emacs is distributed in the hope that it will be useful,
  16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 ;; GNU General Public License for more details.
  19
  20 ;; You should have received a copy of the GNU General Public License
  21 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  22 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  23 ;; Boston, MA 02110-1301, USA.
  24
  25 ;;; Commentary:
  26
  27 ;; This code provides functions to list and edit the values of all global
  28 ;; option variables known to loaded Emacs Lisp code.  There are two entry
  29 ;; points, `list-options' and `edit' options'.  The latter enters a major
  30 ;; mode specifically for editing option values.  Do `M-x describe-mode' in
  31 ;; that context for more details.
  32
  33 ;; The customization buffer feature is intended to make this obsolete.
  34
  35 ;;; Code:
  36
  37 ;;;###autoload
  38 (defun list-options ()
  39   "Display a list of Emacs user options, with values and documentation.
  40 It is now better to use Customize instead."
  41   (interactive)
  42   (with-output-to-temp-buffer "*List Options*"
  43     (let (vars)
  44       (princ "This facility is obsolete; we recommend using M-x customize instead.")
  45
  46       (mapatoms (function (lambda (sym)
  47                             (if (user-variable-p sym)
  48                                 (setq vars (cons sym vars))))))
  49       (setq vars (sort vars 'string-lessp))
  50       (while vars
  51         (let ((sym (car vars)))
  52           (when (boundp sym)
  53             (princ ";; ")
  54             (prin1 sym)
  55             (princ ":\n\t")
  56             (prin1 (symbol-value sym))
  57             (terpri)
  58             (princ (substitute-command-keys
  59                     (documentation-property sym 'variable-documentation)))
  60             (princ "\n;;\n"))
  61           (setq vars (cdr vars))))
  62       (with-current-buffer "*List Options*"
  63         (Edit-options-mode)
  64         (setq buffer-read-only t)))))
  65
  66 ;;;###autoload
  67 (defun edit-options ()
  68   "Edit a list of Emacs user option values.
  69 Selects a buffer containing such a list,
  70 in which there are commands to set the option values.
  71 Type \\[describe-mode] in that buffer for a list of commands.
  72
  73 The Custom feature is intended to make this obsolete."
  74   (interactive)
  75   (list-options)
  76   (pop-to-buffer "*List Options*"))
  77
  78 (defvar Edit-options-mode-map
  79   (let ((map (make-keymap)))
  80     (define-key map "s" 'Edit-options-set)
  81     (define-key map "x" 'Edit-options-toggle)
  82     (define-key map "1" 'Edit-options-t)
  83     (define-key map "0" 'Edit-options-nil)
  84     (define-key map "p" 'backward-paragraph)
  85     (define-key map " " 'forward-paragraph)
  86     (define-key map "n" 'forward-paragraph)
  87     map)
  88   "")
  89
  90 ;; Edit Options mode is suitable only for specially formatted data.
  91 (put 'Edit-options-mode 'mode-class 'special)
  92
  93 (defun Edit-options-mode ()
  94   "\\<Edit-options-mode-map>\
  95 Major mode for editing Emacs user option settings.
  96 Special commands are:
  97 \\[Edit-options-set] -- set variable point points at.  New value read using minibuffer.
  98 \\[Edit-options-toggle] -- toggle variable, t -> nil, nil -> t.
  99 \\[Edit-options-t] -- set variable to t.
 100 \\[Edit-options-nil] -- set variable to nil.
 101 Changed values made by these commands take effect immediately.
 102
 103 Each variable description is a paragraph.
 104 For convenience, the characters \\[backward-paragraph] and \\[forward-paragraph] move back and forward by paragraphs."
 105   (kill-all-local-variables)
 106   (set-syntax-table emacs-lisp-mode-syntax-table)
 107   (use-local-map Edit-options-mode-map)
 108   (make-local-variable 'paragraph-separate)
 109   (setq paragraph-separate "[^\^@-\^?]")
 110   (make-local-variable 'paragraph-start)
 111   (setq paragraph-start "\t")
 112   (setq truncate-lines t)
 113   (setq major-mode 'Edit-options-mode)
 114   (setq mode-name "Options")
 115   (run-mode-hooks 'Edit-options-mode-hook))
 116
 117 (defun Edit-options-set () (interactive)
 118   (Edit-options-modify
 119    (lambda (var) (eval-minibuffer (concat "New " (symbol-name var) ": ")))))
 120
 121 (defun Edit-options-toggle () (interactive)
 122   (Edit-options-modify (lambda (var) (not (symbol-value var)))))
 123
 124 (defun Edit-options-t () (interactive)
 125   (Edit-options-modify (lambda (var) t)))
 126
 127 (defun Edit-options-nil () (interactive)
 128   (Edit-options-modify (lambda (var) nil)))
 129
 130 (defun Edit-options-modify (modfun)
 131   (save-excursion
 132    (let ((buffer-read-only nil) var pos)
 133      (re-search-backward "^;; \\|\\`")
 134      (forward-char 3)
 135      (setq pos (point))
 136      (save-restriction
 137        (narrow-to-region pos (progn (end-of-line) (1- (point))))
 138        (goto-char pos)
 139        (setq var (read (current-buffer))))
 140      (goto-char pos)
 141      (forward-line 1)
 142      (forward-char 1)
 143      (save-excursion
 144        (set var (funcall modfun var)))
 145      (kill-sexp 1)
 146      (prin1 (symbol-value var) (current-buffer)))))
 147
 148 (provide 'options)
 149
 150 ;;; arch-tag: d18211a1-f3fb-48c9-a449-d5acde406a3c
 151 ;;; options.el ends here