bug#15746: 24.3; [PATCH] bookmark should confirm when overwrite

[Leo Liu <sdl.web@gmail.com>]

On 2013-10-30 10:11 +0800, Stefan Monnier wrote:
> How 'bout the following:
> - change bookmark-set to emit a clear message when it updates an
>   existing message, as well as recording the previous value somewhere.
> - provide a bookmark-undo command so the user can undo his
>   bookmark-set when he discovers that he has just changed an existing
>   bookmark by mistake.
> This way, we avoid prompting Drew annoyingly when he knows full well
> he's updating the bookmark.
> Leo, would that be sufficient to avoid the regrets, or did you realize
> too late for a bookmark-undo to be of any use?

Undo in this case is less intuitive than when editing text. I think the
right moment to decide overwriting is when creating the bookmark. So
maybe we could provide a variable to control this confirmation
behaviour? But I agree with Karl the default should provide
confirmation.

BTW, I use bookmark as some sort of persistent registers that I can make
use another day another place. I rsync bookmarks to a few machines so
bookmark-save-flag is 1 to make sure the db is always fully in disk.

Leo