Re: Shift selection using interactive spec

[Chong Yidong <cyd@stupidchicken.com>]

storm@cua.dk (Kim F. Storm) writes:

> Now, before you settle on a solution, maybe you should also consider
> how to handle the delete-selection-mode in a sensible way without
> using the current pre-command-hook + command property approach.
>
> Of course, since shift-select is promoted to a standard feature by
> modifying the relevant commands, we can just take the same approach
> with delete-selection-mode, i.e. modify the relevant commands to
> simply honour delsel mode.

There are two possible behaviors:

1. If transient mark mode is on, activating shift selection should
resets and activates the mark, and the first unshifted command should
then return transient mark mode to its original non-nil value.  Thus
shift selection "stacks" on top of transient mark mode.  I am not
certain if there is a clean way to do this.  Maybe allow
transient-mark-mode to take the form of a list?  Any suggestions?

2. Shift selection commands activate the mark if it is not active, and
extends the region if the mark is activate.  Thus [S-right right
right] would do the same thing as [S-right S-right S-right].  This
would be rather easy to implement.  Though this behavior sounds
strange, it actually mirrors the way mouse selection currently works
in transient-mark-mode.