| 1 | ;;; delsel.el --- delete selection if you insert |
| 2 | |
| 3 | ;; Copyright (C) 1992, 1997, 1998, 2001, 2002, 2003, 2004, |
| 4 | ;; 2005, 2006, 2007, 2008 Free Software Foundation, Inc. |
| 5 | |
| 6 | ;; Author: Matthieu Devin <devin@lucid.com> |
| 7 | ;; Maintainer: FSF |
| 8 | ;; Created: 14 Jul 92 |
| 9 | ;; Keywords: convenience emulations |
| 10 | |
| 11 | ;; This file is part of GNU Emacs. |
| 12 | |
| 13 | ;; GNU Emacs is free software: you can redistribute it and/or modify |
| 14 | ;; it under the terms of the GNU General Public License as published by |
| 15 | ;; the Free Software Foundation, either version 3 of the License, or |
| 16 | ;; (at your option) any later version. |
| 17 | |
| 18 | ;; GNU Emacs is distributed in the hope that it will be useful, |
| 19 | ;; but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 20 | ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 21 | ;; GNU General Public License for more details. |
| 22 | |
| 23 | ;; You should have received a copy of the GNU General Public License |
| 24 | ;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. |
| 25 | |
| 26 | ;;; Commentary: |
| 27 | |
| 28 | ;; This file makes the active region be pending delete, meaning that |
| 29 | ;; text inserted while the region is active will replace the region contents. |
| 30 | ;; This is a popular behavior of personal computers text editors. |
| 31 | |
| 32 | ;; Interface: |
| 33 | |
| 34 | ;; Commands which will delete the selection need a 'delete-selection |
| 35 | ;; property on their symbols; commands which insert text but don't |
| 36 | ;; have this property won't delete the selection. It can be one of |
| 37 | ;; the values: |
| 38 | ;; 'yank |
| 39 | ;; For commands which do a yank; ensures the region about to be |
| 40 | ;; deleted isn't yanked. |
| 41 | ;; 'supersede |
| 42 | ;; Delete the active region and ignore the current command, |
| 43 | ;; i.e. the command will just delete the region. |
| 44 | ;; 'kill |
| 45 | ;; `kill-region' is used on the selection, rather than |
| 46 | ;; `delete-region'. (Text selected with the mouse will typically |
| 47 | ;; be yankable anyhow.) |
| 48 | ;; non-nil |
| 49 | ;; The normal case: delete the active region prior to executing |
| 50 | ;; the command which will insert replacement text. |
| 51 | |
| 52 | ;;; Code: |
| 53 | |
| 54 | ;;;###autoload |
| 55 | (defalias 'pending-delete-mode 'delete-selection-mode) |
| 56 | |
| 57 | ;;;###autoload |
| 58 | (define-minor-mode delete-selection-mode |
| 59 | "Toggle Delete Selection mode. |
| 60 | With prefix ARG, turn Delete Selection mode on if ARG is |
| 61 | positive, off if ARG is not positive. |
| 62 | |
| 63 | When Delete Selection mode is enabled, Transient Mark mode is also |
| 64 | enabled and typed text replaces the selection if the selection is |
| 65 | active. Otherwise, typed text is just inserted at point regardless of |
| 66 | any selection." |
| 67 | :global t :group 'editing-basics |
| 68 | (if (not delete-selection-mode) |
| 69 | (remove-hook 'pre-command-hook 'delete-selection-pre-hook) |
| 70 | (add-hook 'pre-command-hook 'delete-selection-pre-hook) |
| 71 | (transient-mark-mode t))) |
| 72 | |
| 73 | (defun delete-active-region (&optional killp) |
| 74 | (if killp |
| 75 | (kill-region (point) (mark)) |
| 76 | (delete-region (point) (mark))) |
| 77 | t) |
| 78 | |
| 79 | (defun delete-selection-pre-hook () |
| 80 | (when (and delete-selection-mode transient-mark-mode mark-active |
| 81 | (not buffer-read-only)) |
| 82 | (let ((type (and (symbolp this-command) |
| 83 | (get this-command 'delete-selection)))) |
| 84 | (condition-case data |
| 85 | (cond ((eq type 'kill) |
| 86 | (delete-active-region t)) |
| 87 | ((eq type 'yank) |
| 88 | ;; Before a yank command, make sure we don't yank the |
| 89 | ;; head of the kill-ring that really comes from the |
| 90 | ;; currently active region we are going to delete. |
| 91 | ;; That would make yank a no-op. |
| 92 | (when (and (string= (buffer-substring-no-properties (point) (mark)) |
| 93 | (car kill-ring)) |
| 94 | (fboundp 'mouse-region-match) |
| 95 | (mouse-region-match)) |
| 96 | (current-kill 1)) |
| 97 | (delete-active-region)) |
| 98 | ((eq type 'supersede) |
| 99 | (let ((empty-region (= (point) (mark)))) |
| 100 | (delete-active-region) |
| 101 | (unless empty-region |
| 102 | (setq this-command 'ignore)))) |
| 103 | (type |
| 104 | (delete-active-region) |
| 105 | (if (and overwrite-mode (eq this-command 'self-insert-command)) |
| 106 | (let ((overwrite-mode nil)) |
| 107 | (self-insert-command (prefix-numeric-value current-prefix-arg)) |
| 108 | (setq this-command 'ignore))))) |
| 109 | (file-supersession |
| 110 | ;; If ask-user-about-supersession-threat signals an error, |
| 111 | ;; stop safe_run_hooks from clearing out pre-command-hook. |
| 112 | (and (eq inhibit-quit 'pre-command-hook) |
| 113 | (setq inhibit-quit 'delete-selection-dummy)) |
| 114 | (signal 'file-supersession (cdr data))) |
| 115 | (text-read-only |
| 116 | ;; This signal may come either from `delete-active-region' or |
| 117 | ;; `self-insert-command' (when `overwrite-mode' is non-nil). |
| 118 | ;; To avoid clearing out `pre-command-hook' we handle this case |
| 119 | ;; by issuing a simple message. Note, however, that we do not |
| 120 | ;; handle all related problems: When read-only text ends before |
| 121 | ;; the end of the region, the latter is not deleted but any |
| 122 | ;; subsequent insertion will succeed. We could avoid this case |
| 123 | ;; by doing a (setq this-command 'ignore) here. This would, |
| 124 | ;; however, still not handle the case where read-only text ends |
| 125 | ;; precisely where the region starts: In that case the deletion |
| 126 | ;; would succeed but the subsequent insertion would fail with a |
| 127 | ;; text-read-only error. To handle that case we would have to |
| 128 | ;; investigate text properties at both ends of the region and |
| 129 | ;; skip the deletion when inserting text is forbidden there. |
| 130 | (message "Text is read-only") (ding)))))) |
| 131 | |
| 132 | (put 'self-insert-command 'delete-selection t) |
| 133 | (put 'self-insert-iso 'delete-selection t) |
| 134 | |
| 135 | (put 'yank 'delete-selection 'yank) |
| 136 | (put 'clipboard-yank 'delete-selection 'yank) |
| 137 | (put 'insert-register 'delete-selection t) |
| 138 | |
| 139 | (put 'delete-backward-char 'delete-selection 'supersede) |
| 140 | (put 'backward-delete-char-untabify 'delete-selection 'supersede) |
| 141 | (put 'delete-char 'delete-selection 'supersede) |
| 142 | |
| 143 | (put 'newline-and-indent 'delete-selection t) |
| 144 | (put 'newline 'delete-selection t) |
| 145 | (put 'open-line 'delete-selection 'kill) |
| 146 | |
| 147 | ;; This is very useful for cancelling a selection in the minibuffer without |
| 148 | ;; aborting the minibuffer. |
| 149 | (defun minibuffer-keyboard-quit () |
| 150 | "Abort recursive edit. |
| 151 | In Delete Selection mode, if the mark is active, just deactivate it; |
| 152 | then it takes a second \\[keyboard-quit] to abort the minibuffer." |
| 153 | (interactive) |
| 154 | (if (and delete-selection-mode transient-mark-mode mark-active) |
| 155 | (setq deactivate-mark t) |
| 156 | (abort-recursive-edit))) |
| 157 | |
| 158 | (define-key minibuffer-local-map "\C-g" 'minibuffer-keyboard-quit) |
| 159 | (define-key minibuffer-local-ns-map "\C-g" 'minibuffer-keyboard-quit) |
| 160 | (define-key minibuffer-local-completion-map "\C-g" 'minibuffer-keyboard-quit) |
| 161 | (define-key minibuffer-local-must-match-map "\C-g" 'minibuffer-keyboard-quit) |
| 162 | (define-key minibuffer-local-isearch-map "\C-g" 'minibuffer-keyboard-quit) |
| 163 | |
| 164 | (defun delsel-unload-function () |
| 165 | "Unload the Delete Selection library." |
| 166 | (define-key minibuffer-local-map "\C-g" 'abort-recursive-edit) |
| 167 | (define-key minibuffer-local-ns-map "\C-g" 'abort-recursive-edit) |
| 168 | (define-key minibuffer-local-completion-map "\C-g" 'abort-recursive-edit) |
| 169 | (define-key minibuffer-local-must-match-map "\C-g" 'abort-recursive-edit) |
| 170 | (define-key minibuffer-local-isearch-map "\C-g" 'abort-recursive-edit) |
| 171 | (dolist (sym '(self-insert-command self-insert-iso yank clipboard-yank |
| 172 | insert-register delete-backward-char backward-delete-char-untabify |
| 173 | delete-char newline-and-indent newline open-line)) |
| 174 | (put sym 'delete-selection nil)) |
| 175 | ;; continue standard unloading |
| 176 | nil) |
| 177 | |
| 178 | (provide 'delsel) |
| 179 | |
| 180 | ;; arch-tag: 1e388890-1b50-4ed0-9347-763b1343b6ed |
| 181 | ;;; delsel.el ends here |