Re: Shift selection using interactive spec

[Chong Yidong <cyd@stupidchicken.com>]

David Kastrup <dak@gnu.org> writes:

>> 3. Use a non-letter interactive code, analogous to @ and *, that
>>    causes Fcall_interactively to perform the handling of
>>    transient-mark-mode automagically.  This was the code I showed.
>>    Because it's a non-letter code, we don't need to change the
>>    argument list.  This approach needs the least new code, and might
>>    be less disruptive, but it's obviously a little magical.
>>
>> 3a. As above, but also for direct keybindings with the shift modifier.
>
> 3 has my vote.  I am not sure about the meaning or implications of 3a.


If you type `S-right', read_key_sequence tries to find a keybinding
for `S-right'.  If is none, it automatically tries `right', which in
this case is bound to forward-char.  So `S-right', translated to
`right', runs foward-char.

If you bind `S-right' to some other command, this translation won't
occur: `S-right' runs that new command.

That's what I mean by shift translation.  It raises the orthogonal
issue of whether we want to tie shift-selection to this shift
translation business.  Or do we simply activate it when there is a
shift modifier present in the keybinding?

My inclination is toward the former, but this issue is subtle and
needs more analysis.