Re: Reopen bug 535: Problem with highlit regions on Linux virtual terminal

[Alan Mackenzie]

Hi, Stephen!

On Wed, Apr 08, 2009 at 06:26:13PM +0900, Stephen J. Turnbull wrote:
> Alan Mackenzie writes:

>  > This is a misuse of the word "active",

> Any dictionary will quickly show that this usage of "active" is
> well-known.  From dictionary.reference.com:

> 2.    being in a state of existence, progress, or motion:
>         active hostilities.

> 5.    characterized by action, motion, volume, use, participation,
>       etc.: an active market in wheat; an active list of
>       subscribers.

Well, hostilities kill people, and markets shift wheat around, at least
when they're of sufficient granularity.  _Processes_ can clearly be
active merely by "existing".  An active list?  OK, point to you.  ;-)

>  > "Active" is the wrong word.  Possibly "Reactive" would be a suitable
>  > one - a "reactive region" being one which reacts to commands
>  > directed at it.

> I don't think that's as good a term as "active".  The region is not an
> object with methods it uses to "react" to commands.  It is an object
> to which things may be done, unless it is inactive.  "Receptive
> region" might be more accurate, but unfortunately there is no verb "to
> receptivate".  I think documenters would mutiny if they had to write
> "to activate the receptivity of the region".

:-)  There seems to be a hole in the English language here; there doesn't
seem to be an adjective meaning "in a state in which things can be done
to it".  Maybe in Japanese?

>  > Do you have definitions of (as contrasted to a discussion around)
>  > "active region" and "active mark" that you could contribute to the
>  > Emacs manual?

> Not really.  As you say, transient-mark-mode is complex.  And we've
> been through this discussion before, IIRC, and the XEmacs terminology
> was considered inappropriate for Emacs.

Pity.  `zmacs-regions' is much less confusing than `transient-mark-mode';
the mark isn't transient, and neither is the mode.  Well, Germany was in
transient-mark-mode from 1989 to 2001, but that's something different.

> To recap, XEmacs does not have a concept of "active mark" (or if that
> term is used, I guess it is identical to "the mark", ie, the mark on
> the top of the mark stack).  It does have two concepts of active
> region, the more often used of which is `region-exists-p' (for
> compatibility with code written for Emacs):

>     Return t if the region exists.
>     If active regions are in use (i.e. `zmacs-regions' is true), this
>     means that the region is active.  Otherwise, this means that the
>     user has pushed a mark in this buffer at some point in the past.

This seems to be the interpretation intended for `mark-active' by the
hacker who created it.

> the other being `region-active-p':

>     (defun region-active-p () (and zmacs-regions (region-exists-p)))

This seems to be the interpretation of `mark-active' understood in
desktop.el.

> where zmacs-regions is the XEmacs equivalent to transient-mark-mode.

Yes.

-- 
Alan Mackenzie (Nuremberg, Germany).