-;;; delsel.el --- delete selection if you insert
+;;; delsel.el --- delete selection if you insert -*- lexical-binding:t -*-
-;; Copyright (C) 1992, 1997-1998, 2001-2014 Free Software Foundation,
+;; Copyright (C) 1992, 1997-1998, 2001-2016 Free Software Foundation,
;; Inc.
;; Author: Matthieu Devin <devin@lucid.com>
;; property on their symbols; commands which insert text but don't
;; have this property won't delete the selection. It can be one of
;; the values:
-;; 'yank
+;; `yank'
;; For commands which do a yank; ensures the region about to be
-;; deleted isn't yanked.
-;; 'supersede
+;; deleted isn't immediately yanked back, which would make the
+;; command a no-op.
+;; `supersede'
;; Delete the active region and ignore the current command,
-;; i.e. the command will just delete the region.
-;; 'kill
+;; i.e. the command will just delete the region. This is for
+;; commands that normally delete small amounts of text, like
+;; a single character -- they will instead delete the whole
+;; active region.
+;; `kill'
;; `kill-region' is used on the selection, rather than
;; `delete-region'. (Text selected with the mouse will typically
;; be yankable anyhow.)
;; t
;; The normal case: delete the active region prior to executing
;; the command which will insert replacement text.
-;; <function>
+;; FUNCTION
;; For commands which need to dynamically determine this behavior.
-;; The function should return one of the above values or nil.
+;; FUNCTION should take no argument and return one of the above
+;; values, or nil. In the latter case, FUNCTION should itself
+;; do with the active region whatever is appropriate."
;;; Code:
+(defvar delete-selection-save-to-register nil
+ "If non-nil, deleted region text is stored in this register.
+Value must be the register (key) to use.")
+
;;;###autoload
(defalias 'pending-delete-mode 'delete-selection-mode)
When Delete Selection mode is enabled, typed text replaces the selection
if the selection is active. Otherwise, typed text is just inserted at
-point regardless of any selection."
+point regardless of any selection. Also, commands that normally delete
+just one character will delete the entire selection instead.
+
+See `delete-selection-helper' and `delete-selection-pre-hook' for
+information on adapting behavior of commands in Delete Selection mode."
:global t :group 'editing-basics
(if (not delete-selection-mode)
(remove-hook 'pre-command-hook 'delete-selection-pre-hook)
(add-hook 'pre-command-hook 'delete-selection-pre-hook)))
+(defvar delsel--replace-text-or-position nil)
+
(defun delete-active-region (&optional killp)
"Delete the active region.
If KILLP in not-nil, the active region is killed instead of deleted."
- (if killp
- ;; Don't allow `kill-region' to change the value of `this-command'.
- (let (this-command)
- (kill-region (point) (mark) t))
- (funcall region-extract-function 'delete-only))
- t)
+ (cond
+ (killp
+ ;; Don't allow `kill-region' to change the value of `this-command'.
+ (let (this-command)
+ (kill-region (point) (mark) t)))
+ (delete-selection-save-to-register
+ (set-register delete-selection-save-to-register
+ (funcall region-extract-function t))
+ (setq delsel--replace-text-or-position
+ (cons (current-buffer)
+ (and (consp buffer-undo-list) (car buffer-undo-list)))))
+ (t
+ (funcall region-extract-function 'delete-only))))
+
+(defun delete-selection-repeat-replace-region (arg)
+ "Repeat replacing text of highlighted region with typed text.
+Search for the next stretch of text identical to the region last replaced
+by typing text over it and replaces it with the same stretch of text.
+With ARG, repeat that many times. `C-u' means until end of buffer."
+ (interactive "P")
+ (let ((old-text (and delete-selection-save-to-register
+ (get-register delete-selection-save-to-register)))
+ (count (if (consp arg) (point-max)
+ (prefix-numeric-value current-prefix-arg))))
+ (if (not (and old-text
+ (> (length old-text) 0)
+ (or (stringp delsel--replace-text-or-position)
+ (buffer-live-p (car delsel--replace-text-or-position)))))
+ (message "No known previous replacement")
+ ;; If this is the first use after overwriting regions,
+ ;; find the replacement text by looking at the undo list.
+ (when (consp delsel--replace-text-or-position)
+ (let ((buffer (car delsel--replace-text-or-position))
+ (elt (cdr delsel--replace-text-or-position)))
+ (setq delsel--replace-text-or-position nil)
+ (with-current-buffer buffer
+ (save-restriction
+ (widen)
+ ;; Find the text that replaced the region via the undo list.
+ (let ((ul buffer-undo-list) u s e)
+ (when elt
+ (while (consp ul)
+ (setq u (car ul) ul (cdr ul))
+ (cond
+ ((eq u elt) ;; got it
+ (setq ul nil))
+ ((and (consp u) (integerp (car u)) (integerp (cdr u)))
+ (if (and s (= (cdr u) s))
+ (setq s (car u))
+ (setq s (car u) e (cdr u)))))))
+ (cond ((and s e (<= s e) (= s (mark t)))
+ (setq delsel--replace-text-or-position
+ (filter-buffer-substring s e))
+ (set-text-properties
+ 0 (length delsel--replace-text-or-position)
+ nil delsel--replace-text-or-position))
+ ((and (null s) (eq u elt)) ;; Nothing inserted.
+ (setq delsel--replace-text-or-position ""))
+ (t
+ (message "Cannot locate replacement text"))))))))
+ (while (and (> count 0)
+ delsel--replace-text-or-position
+ (search-forward old-text nil t))
+ (replace-match delsel--replace-text-or-position nil t)
+ (setq count (1- count))))))
(defun delete-selection-helper (type)
"Delete selection according to TYPE:
`yank'
For commands which do a yank; ensures the region about to be
- deleted isn't yanked.
+ deleted isn't immediately yanked back, which would make the
+ command a no-op.
`supersede'
Delete the active region and ignore the current command,
- i.e. the command will just delete the region.
+ i.e. the command will just delete the region. This is for
+ commands that normally delete small amounts of text, like
+ a single character -- they will instead delete the whole
+ active region.
`kill'
`kill-region' is used on the selection, rather than
- `delete-region'. (Text selected with the mouse will typically
- be yankable anyhow.)
- t
- The normal case: delete the active region prior to executing
- the command which will insert replacement text.
+ `delete-region'. (Text selected with the mouse will
+ typically be yankable anyhow.)
FUNCTION
- For commands which need to dynamically determine this behavior.
- FUNCTION should take no argument and return one of the above values or nil."
+ For commands which need to dynamically determine this
+ behavior. FUNCTION should take no argument and return a
+ value acceptable as TYPE, or nil. In the latter case,
+ FUNCTION should itself do with the active region whatever is
+ appropriate.
+ Other non-nil values
+ The normal case: delete the active region prior to executing
+ the command which will insert replacement text."
(condition-case data
- (cond ((eq type 'kill)
+ (cond ((eq type 'kill) ;Deprecated, backward compatibility.
(delete-active-region t)
(if (and overwrite-mode
(eq this-command 'self-insert-command))
(delete-selection-helper (and (symbolp this-command)
(get this-command 'delete-selection)))))
-(put 'self-insert-command 'delete-selection
- (lambda ()
- (not (run-hook-with-args-until-success
- 'self-insert-uses-region-functions))))
+(defun delete-selection-uses-region-p ()
+ "Return t when the current command will be using the region
+rather than having `delete-selection' delete it, nil otherwise.
+
+This function is intended for use as the value of the
+`delete-selection' property of a command, and shouldn't be used
+for anything else."
+ (not (run-hook-with-args-until-success
+ 'self-insert-uses-region-functions)))
+
+(put 'self-insert-command 'delete-selection 'delete-selection-uses-region-p)
(put 'insert-char 'delete-selection t)
(put 'quoted-insert 'delete-selection t)
(put 'reindent-then-newline-and-indent 'delete-selection t)
(put 'newline-and-indent 'delete-selection t)
(put 'newline 'delete-selection t)
-(put 'open-line 'delete-selection 'kill)
+(put 'electric-newline-and-maybe-indent 'delete-selection t)
+(put 'open-line 'delete-selection t)
;; This is very useful for canceling a selection in the minibuffer without
;; aborting the minibuffer.