Subject: bug#5018: 23.1.50; Feature request: truncate-lines text property

From: Michael Brand <[email-masked]>
Date: Tue, 6 Jun 2017 21:40:02 +0200

Hi Eli

On Mon, Jun 5, 2017 at 5:42 PM, Eli Zaretskii <[email-masked]> wrote:

> If you decide to try it, I suggest to start by looking at my recent
> changes that introduced hscrolling of only the current line.  This
> feature should use similar techniques and touch the same places.

Thanks for the pointer, looks good for a start.

> The property on a newline makes the preceding line truncated or the
> following line?  If the former, than what about the last line in a
> buffer that doesn't end in a newline?  Also, looking for the property
> in a very long line could slow down redisplay, since it would need to
> know about this when it gets to the first character of the line.

I would agree to set the property on the first char of non-empty
lines.

> What other solution is possible?

Not that I would know. With the knowledge about the internals missing
on my side it looked unnatural in the first place to use a property of
a char for a property related to a line.

> It could well be that the first variant is easier to implement.

Good to know. I just stumbled over the new current-line hscrolling in
the commit log, interesting.

> I'm not sure.  Most if not all of the relevant people read the bug
> list as well.  Perhaps post a short message to emacs-devel telling the
> interested people to read this discussion either via the bug tracker
> or via the bug-gnu-emacs list.

Bug tracker and bug-gnu-emacs list seems OK to me.

Michael