Re: Preserving sanity in Emacs [Re: rampant region highlighting]

[Lennart Borgman (gmail)]

Alan Mackenzie wrote:
> Morning, Lennart!

Morning, Alan!

> On Mon, Apr 07, 2008 at 11:37:09PM +0200, Lennart Borgman (gmail) wrote:
> > Alan Mackenzie wrote:
> > > > I acknowledge that having the point always on-screen has benefits too
> > > > (though e.g. a fringe indicator could "point towards the offscreen
> > > > point" to address some concerns there...), but what if I'm just
> > > > scrolling up to look at something?  Martin's hack ensured that I can
> > > > scroll away to have a look, and the point will reliably be where I left
> > > > it when I scrolled back.
>
> > > The functions you're talking about are fulfilled in Emacs by the mark,
> > > not the point.  I frequently scoll a bit to look at things.  Then I
> > > scroll back to get where I was, unless I want to stay where I've got to.
>
> > > The point is, by your mechanism, having scrolled away from point (leaving
> > > point off the screen), how do you then indicate where on the screen you
> > > want point to be set to, and how do you set point there?  The general
> > > Emacs answer is that you indicate a position by setting point.  Hmm.
> > > We're going round in circles.  (You're presumably going to say "you click
> > > the mouse to set point."  This violates the Emacs principle that
> > > everything must be doable without a mouse.)
>
> > Another way to look at this would perhaps be to:
>
> > - Regard the buffer in a kind of read-only state when the window-point 
> > is outside the window ;-)
>
> Hmm.
>
> > - If a command concerns the current buffer and it is not a scroll 
> > command then just bring back window-point to where it was inside the 
> > window before scrolling.
>
> Sorry, I can't parse that.  What is "window-point"?  Does "where it was"
> refer to the buffer position, or the position on the screen relative to
> the top of the window?

window-point? Just a little joke. We are talking about the buffer point 
in the current window. The function window-point returns that. 
window-point may in the situation pictured above still return the point, 
but it is outside the window ... (or maybe it could return nil?)

"where it was": I meant the position on the screen.

> > Don't do more (ie do not execute the command), just tell that point was
> > outside of the window therefore have been brought back.
>
> Don't execute the command?  Yikes!!  Yet one more frivolous item of state
> to clog up one's brain.

Yes, I think that must be the price if you always want to be able to see 
what you are doing. (This could be made an option - perhaps.)

> And a few million "..., except when ...."s to
> clog up commands' doc strings.

Not much to add there I think. A note somewhere about scrolling is all I 
can see is really needed.