Re: Native line numbers, final testing

[Eli Zaretskii]

> From: Alex <address@hidden>
> Cc: address@hidden
> Date: Sat, 01 Jul 2017 15:00:50 -0600
> 
> It's not intuitive to me why this occurs between lines with the same
> display line number width. If vertical-motion uses the same heuristic as
> display of line numbers, then why is the column changing between lines
> even when the width of line numbers isn't?

Because vertical-motion thinks the display uses N+1 columns whereas it
actually uses only N.

> Is it because it's using the heuristic with different inputs?

Yes.  The important input is the actual window-start point.

> If so, can't they be modified to achieve the same results as the
> display of line numbers?

I couldn't (yet) find a way of doing that.

> Why is it necessary for line numbers to actually affect the vertical
> position of characters in the buffer?

Because vertical-motion does its column calculation in pixels, C-n/C-p
need to adjust the calculations due to the pixels occupied by line
numbers.

> I suppose it's a bit late to be asking this question, but the
> approach from an outside view feels odd. I don't know what the
> options were, but it's odd that line numbers aren't in their own
> special area like in (n)linum. Does the display engine not work well
> with margins?

I firmly believe that line numbers should not be displayed on the
margins, because that produces problems for packages that want to
display stuff there.