bug#11191: C-x C-x does not activate the selection anymore with cua-selection-mode

[Kim Storm]

On 04/09/2012 07:50 AM, Dan Nicolaescu wrote:
> Chong Yidong<cyd@gnu.org>  writes:
>
> > Dan Nicolaescu<dann@gnu.org>  writes:
> >
> > [recipe edited]
> >
> > > emacs -Q
> > > M-x cua-selection-mode RET
> > > M-<
> > > C-SPC C-f C-f C-f C-g
> > > C-x C-x
> > >
> > > now the selection should be active, but it is not.
> > > This worked in emacs-23.3, so this is a regression.
> > Looks like this change was made deliberately:
> >
> >    revno: 102844
> >    committer: Kim F. Storm<storm@cua.dk>
> >    branch nick: trunk
> >    timestamp: Fri 2011-01-14 16:06:17 +0100
> >    message:
> >    * emulation/cua-base.el (cua--init-keymaps):
> >    Remap exchange-point-and-mark in cua-global-keymap.
> >
> > The docstring of `cua-exchange-point-and-mark' says it does not activate
> > the mark.
> > Kim, could you confirm that this was the intention?
>
> In emacs-22.3 and 23.3 it does activate the mark.
> C-x C-x also activates the mark in the trunk without
> cua-selection-mode.
>
> Wouldn't it be better that instead of changing something that has been
> present in two major releases and is consistent with the default behavior,
> to change the docstring?

The current behaviour is "by design"

Personally, I find it very annoying if C-x C-x activates the mark with 
cua-mode - as it becomes very
hard to enter another C-x C-x to cancel it (it actually requires three 
C-x typed rapidly -- otherwise
it will delete the region.  That is why cua-exchange-point-and-mark 
doesn't activate the mark
by default.

- but with reference to bug #6199 on the same subject,  I have already 
approved to change the behaviour
--- if anyone feels it is necessary.

I think the following version should do the trick

(defun cua-exchange-point-and-mark (arg)
  "Exchanges point and mark.
Don't activate the mark if a prefix argument is given."
  (interactive "P")
  (let ((ma mark-active))
    (exchange-point-and-mark)
    (if cua--rectangle
    (cua--rectangle-corner 0))
    (if arg
    (setq mark-active ma))))