Any way to select a region using `S-down-mouse-1` without saving the region as a kill?

Question

Using emacsw32.

The usual suggested way to make a selection using S-down-mouse-1 is to bind that to mouse-save-then-kill.

Is there a similar command which selects a region, but does not save the region?

The goal is to have the following scenario:

I have some text in the kill ring. I make a selection by holding shift and clicking the left mouse button. I delete the selection using <delete>. Then I paste something (using cua-paste) and this something is not the same as the region I just deleted.

Answer 1

The following works for me:

1. Start emacs-w32 -Q
2. Paste the following code into the *scratch*-buffer:

(progn
  (cua-mode)
  (global-set-key [S-drag-mouse-1] (lambda (click) (interactive "e") (let (mouse-drag-copy-region) (mouse-set-region click))))
  (global-set-key [S-down-mouse-1] 'mouse-set-point))

111
222
333

3. Execute the progn-form with C-x C-e
4. Select the string "111" with mouse-1 (down and drag) and copy with C-c
5. Shift-select the string "222" with S-down-mouse-1 and S-drag-mouse-1
6. Kill the shift-selected string with del
7. Insert the string "111" from the kill-ring with the key C-v

If I execute M-x emacs-version I get:

GNU Emacs 24.5.1 (x86_64-unknown-cygwin) of 2015-04-10 on desktop-new

It also works with

GNU Emacs 24.3.1 (i686-pc-linux-gnu, GTK+ Version 3.10.7) of 2014-03-07 on toyol, modified by Debian

Note, that del runs delete-forward-char while C-x runs indirectly cua-cut-region which copies the cut text to kill-ring.

delete-forward-char deletes the active region if the variable delete-active-region is set to a non-nil value other than 'kill. The standard setting is t.

Answer 2

It's not clear to me what S-down-mouse-1 has to do with selecting text. In emacs -Q (no init file), holding Shift and pressing mouse-1 brings up mouse-appearance-menu (menu Change Default Buffer Face).

Anyway, you can do what you want using a command that calls delete-region:

(defun del-region-no-kill (beg end)
  "Delete the active region without killing it."
  (interactive "r")
  (delete-region beg end))

For example:

(global-set-key "\C-o" 'del-region-no-kill)