From: Stefan Monnier <monnier@iro.umontreal.ca>
To: martin rudalics <rudalics@gmx.at>
Cc: Eli Zaretskii <eliz@gnu.org>, npostavs@gmail.com, emacs-devel@gnu.org
Subject: Re: "after" variable watchers
Date: Tue, 18 May 2021 11:57:38 -0400 [thread overview]
Message-ID: <jwvtun0nix6.fsf-monnier+emacs@gnu.org> (raw)
In-Reply-To: <5a8b6fc9-cca8-374c-39f8-3f3d0f83fbca@gmx.at> (martin rudalics's message of "Tue, 18 May 2021 17:10:47 +0200")
martin rudalics [2021-05-18 17:10:47] wrote:
>>> window_updeco_window is called indirectly from all places that change a
>>> window's decorations, font or size.
>>
>> Would it make sense to call it more lazily, e.g. as part of redisplay
>> (basically, the watchpoints would just set some dirty bits and then at
>> the beginning of redisplay you'd then run `window_updeco_window` on
>> those windows with the dirty bit set)?
>
> That was my first approach given our current implementation of watch
> points. I spent a couple of weeks on it but it didn't really work out.
> Between the time a variable is set and the time the setting is applied,
> the "realized" values would be inaccurate. These values are, however,
> needed in too many places before we start redisplaying a window.
What was the problem you encountered when you tried to add:
if (<dirty>) window_updeco_window (...);
to the getters of the realized values?
> I do not want to exclude that such a lazy approach could work. But it
> would require more profound changes to the way window sizes and
> decorations are processed than the approach based on "after" variable
> watchers.
You obviously know more about this code, so I can't say much more.
I was just pointing in the direction of using dirty "bits" (it's
actually often better to represent dirty state via things like our
buffer ticks than via actual `dirty` bits) because it's the standard
solution for such problems: experience has usually shown that decoupling
the setting of vars from the execution of the consequences usually leads
to a much more solid design where it's much easier to deal with problems
of inf-loops or (in)efficiency.
Stefan
next prev parent reply other threads:[~2021-05-18 15:57 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-05-17 8:27 "after" variable watchers martin rudalics
2021-05-17 10:23 ` Eli Zaretskii
2021-05-17 16:40 ` martin rudalics
2021-05-17 16:57 ` Eli Zaretskii
2021-05-18 15:10 ` martin rudalics
2021-05-20 13:46 ` Eli Zaretskii
2021-05-24 8:47 ` martin rudalics
2021-05-27 16:51 ` Eli Zaretskii
2021-06-06 7:42 ` martin rudalics
2021-05-17 18:36 ` Stefan Monnier
2021-05-17 18:45 ` Eli Zaretskii
2021-05-17 18:54 ` Stefan Monnier
2021-05-17 18:55 ` Stefan Monnier
2021-05-18 15:10 ` martin rudalics
2021-05-18 15:57 ` Stefan Monnier [this message]
2021-05-18 17:01 ` martin rudalics
2021-05-20 13:49 ` Eli Zaretskii
2021-05-24 8:48 ` martin rudalics
2021-05-27 16:53 ` Eli Zaretskii
2021-05-17 14:57 ` Matt Armstrong
2021-05-17 16:41 ` martin rudalics
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
List information: https://www.gnu.org/software/emacs/
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=jwvtun0nix6.fsf-monnier+emacs@gnu.org \
--to=monnier@iro.umontreal.ca \
--cc=eliz@gnu.org \
--cc=emacs-devel@gnu.org \
--cc=npostavs@gmail.com \
--cc=rudalics@gmx.at \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this public inbox
https://git.savannah.gnu.org/cgit/emacs.git
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).