From: Stefan Monnier <monnier@iro.umontreal.ca>
To: emacs-devel@gnu.org
Subject: Re: Unbalanced change hooks (part 2) [Documentation fix still remaining]
Date: Tue, 30 Aug 2016 17:37:59 -0400 [thread overview]
Message-ID: <jwvh9a2rlyv.fsf-monnier+gmane.emacs.devel@gnu.org> (raw)
In-Reply-To: 20160830205335.GI6672@acm.fritz.box
>> It's trivial to demonstrate that it doesn't:
>> - consider any change between START and END to the buffer.
>> - you can always decompose it into:
>> (a) delete everything from START to point-max.
>> (b) insert at START (now point-max) the rest of the text.
>> - clearly the above deletions and insertions *could* happen, so CC-mode
>> has to handle them and since all changes could be decomposed this way,
>> CC-mode does not *need* to handle any other case.
>> - to handle (a) you don't need to know anything from b-c-f.
>> - to handle (b) you don't need to know anything from b-c-f.
> That's garbage. Pure garbage. I said above in any _REASONABLE_
> fashion, specifically excluding, in the bit you snipped, scanning from
> BOB on every single change.
[ You said "written in any reasonable fashion", so I took it you
referred to the complexity of the code-writing part, not the runtime
complexity of the algorithm. As a matter of fact the above
suggestion makes the code's writing *more* reasonable since you have
to handle fewer distinct cases. ]
Nothing in the above requires scanning from BOB.
And it's reasonable enough (in terms of performance) for all other known
major modes, BTW.
> Even you would start complaining if CC Mode slowed to the slowness it
> would have on implementing anything like you're suggesting.
As a matter fact, my local CC-mode works just the way I describe above
(via syntax-propertize), and I haven't noticed any slowness so far.
>> Daniel's description gives you the added info necessary to know how to
>> detect that situation and what you might want to do about it.
> No, Daniel's description, also Eli's description, by any reasonable
> reading, completely exclude the use of the technique,
Daniel's wording (and Eli as well, tho maybe slightly less crisply) say
precisely what might come up and does not exclude the technique you use.
You could argue that it lacks an argument of what is *frequent*, which
might influence the design choice, but it in no way restrict the
*possible* designs.
> Nowhere do Daniel or Eli document the reality, that b-c-f and a-c-f
> match very close to 100% of the time.
I think it's OK. As you and Daniel have argued, it's "natural" for the
reader to presume that b-c-f and a-c-f will always come in perfect pairs
(and that's also what they will quickly find out when testing or
debugging their code), so there's no need to reinforce this natural
assumption. Instead what the doc needs to focus on is the fact that
this presumption is not always valid and clarify *how* it's invalid.
> The elisp manual places an upper limit on what hackers can do with
> Emacs. That limit is now lower than it was before 25.1. I find that
> a very sad state of affairs.
Your CC-mode design is actually correct w.r.t Daniel's wording.
Its good performance is not guaranteed by this wording since it handles
the non-paired case suboptimally but we rarely (if ever) document
performance-related specification anyway, so most code's performance
design is based on experiments rather than on reading the doc.
> I disagree with you totally.
Wonderful! On the upside, you might like to take a look at the closely
related bug#24340 where you might actually agree with me for once ;-)
Stefan
next prev parent reply other threads:[~2016-08-30 21:37 UTC|newest]
Thread overview: 189+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-07-31 12:16 Unbalanced change hooks (part 2) Alan Mackenzie
2016-07-31 13:58 ` Noam Postavsky
2016-07-31 15:21 ` Alan Mackenzie
2016-07-31 15:03 ` Eli Zaretskii
2016-07-31 17:28 ` Alan Mackenzie
2016-07-31 18:11 ` Eli Zaretskii
2016-07-31 18:52 ` Eli Zaretskii
2016-07-31 19:08 ` Eli Zaretskii
2016-07-31 19:20 ` Noam Postavsky
2016-07-31 21:26 ` Alan Mackenzie
2016-08-01 13:01 ` Stefan Monnier
2016-08-01 13:07 ` Eli Zaretskii
2016-08-01 16:53 ` Alan Mackenzie
2016-08-01 17:15 ` Alan Mackenzie
2016-08-01 19:39 ` Eli Zaretskii
2016-08-01 20:52 ` Alan Mackenzie
2016-08-02 14:44 ` Eli Zaretskii
2016-08-02 16:09 ` Alan Mackenzie
2016-08-02 16:42 ` Eli Zaretskii
2016-08-02 17:24 ` Stefan Monnier
2016-08-07 14:49 ` Alan Mackenzie
2016-08-07 15:09 ` Stefan Monnier
2016-08-07 21:48 ` Alan Mackenzie
2016-08-08 0:55 ` Stefan Monnier
2016-08-02 14:46 ` Stefan Monnier
2016-08-01 19:37 ` Eli Zaretskii
2016-08-02 14:39 ` Stefan Monnier
2016-07-31 18:55 ` Stefan Monnier
2016-07-31 19:26 ` Eli Zaretskii
2016-07-31 21:59 ` Stefan Monnier
2016-08-01 13:09 ` Eli Zaretskii
2016-08-01 14:36 ` Stefan Monnier
2016-08-01 14:48 ` Eli Zaretskii
2016-08-01 15:28 ` Stefan Monnier
2016-07-31 19:33 ` Alan Mackenzie
2016-07-31 19:21 ` Eli Zaretskii
2016-08-09 15:01 ` Alan Mackenzie
2016-08-09 15:14 ` Eli Zaretskii
2016-08-19 14:51 ` Phillip Lord
2016-08-30 1:15 ` Stefan Monnier
2016-08-30 14:34 ` Phillip Lord
2016-08-30 15:11 ` Stefan Monnier
2016-08-31 11:00 ` Phillip Lord
2016-08-31 12:24 ` Stefan Monnier
2016-09-01 6:49 ` Phillip Lord
2016-09-01 13:36 ` Stefan Monnier
2016-09-01 6:40 ` Phillip Lord
2016-09-01 13:33 ` Stefan Monnier
2016-09-02 11:34 ` Phillip Lord
2016-08-30 16:08 ` Eli Zaretskii
2016-08-01 16:38 ` Richard Stallman
2016-08-02 10:15 ` Alan Mackenzie
2016-08-02 10:37 ` Richard Copley
2016-08-02 16:11 ` Alan Mackenzie
2016-08-02 14:57 ` Eli Zaretskii
2016-08-02 16:55 ` Alan Mackenzie
2016-08-02 17:17 ` Eli Zaretskii
2016-08-02 18:30 ` Eli Zaretskii
2016-08-02 19:38 ` Alan Mackenzie
2016-08-03 2:36 ` Eli Zaretskii
2016-08-08 14:36 ` Alan Mackenzie
2016-08-08 15:42 ` Eli Zaretskii
2016-08-08 16:54 ` Alan Mackenzie
2016-08-08 17:17 ` Eli Zaretskii
2016-08-08 18:42 ` Alan Mackenzie
2016-08-08 19:04 ` Eli Zaretskii
2016-08-08 19:54 ` Unbalanced change hooks (part 2) [PATCH] Alan Mackenzie
2016-08-09 15:08 ` Eli Zaretskii
2016-08-09 16:38 ` Unbalanced change hooks (part 2) [Documentation fix still remaining] Alan Mackenzie
2016-08-09 16:42 ` Eli Zaretskii
2016-08-09 18:13 ` Eli Zaretskii
2016-08-09 18:35 ` Alan Mackenzie
2016-08-09 17:14 ` Stefan Monnier
2016-08-09 18:19 ` Eli Zaretskii
2016-08-09 19:09 ` Stefan Monnier
2016-08-10 14:21 ` Eli Zaretskii
2016-08-10 14:56 ` Stefan Monnier
2016-08-10 15:16 ` Alan Mackenzie
2016-08-10 15:44 ` Stefan Monnier
2016-08-10 16:03 ` Eli Zaretskii
2016-08-10 16:11 ` Stefan Monnier
2016-08-18 14:26 ` Eli Zaretskii
2016-08-18 16:56 ` Stefan Monnier
2016-08-19 8:45 ` Alan Mackenzie
2016-08-19 9:12 ` Eli Zaretskii
2016-08-19 9:21 ` Stefan Monnier
2016-08-19 9:39 ` Eli Zaretskii
2016-08-19 9:19 ` Stefan Monnier
2016-08-10 16:18 ` Alan Mackenzie
2016-08-10 16:54 ` Eli Zaretskii
2016-08-10 17:49 ` Alan Mackenzie
2016-08-10 18:10 ` Eli Zaretskii
2016-08-10 18:57 ` Alan Mackenzie
2016-08-10 19:08 ` Eli Zaretskii
2016-08-10 19:50 ` Stefan Monnier
2016-08-11 11:29 ` Alan Mackenzie
2016-08-11 16:43 ` Stefan Monnier
2016-08-28 11:23 ` Daniel Colascione
2016-08-28 15:01 ` Stefan Monnier
2016-08-28 22:16 ` Daniel Colascione
2016-08-28 22:44 ` Stefan Monnier
2016-08-28 23:11 ` Daniel Colascione
2016-08-29 0:09 ` Stefan Monnier
2016-08-29 3:18 ` Daniel Colascione
2016-08-29 13:00 ` Stefan Monnier
2016-08-29 14:51 ` Eli Zaretskii
2016-08-29 15:50 ` Stefan Monnier
2016-08-29 16:22 ` Eli Zaretskii
2016-08-29 15:14 ` Daniel Colascione
2016-08-29 15:44 ` Stefan Monnier
2016-08-30 14:07 ` Phillip Lord
2016-08-30 15:51 ` Eli Zaretskii
2016-08-30 16:22 ` Daniel Colascione
2016-08-30 16:46 ` Eli Zaretskii
2016-08-29 14:50 ` Eli Zaretskii
2016-08-29 15:30 ` Daniel Colascione
2016-08-29 16:20 ` Eli Zaretskii
2016-08-29 16:26 ` Daniel Colascione
2016-08-29 17:01 ` Eli Zaretskii
2016-08-29 17:48 ` Daniel Colascione
2016-08-29 18:04 ` Eli Zaretskii
2016-08-29 18:16 ` Eli Zaretskii
2016-08-30 2:27 ` Daniel Colascione
2016-08-30 2:44 ` Eli Zaretskii
2016-08-30 0:25 ` Stefan Monnier
2016-08-30 2:26 ` Daniel Colascione
2016-08-30 2:38 ` Eli Zaretskii
2016-08-30 2:54 ` Daniel Colascione
2016-08-30 14:20 ` Phillip Lord
2016-08-30 15:08 ` Eli Zaretskii
2016-08-30 12:56 ` Stefan Monnier
2016-08-30 14:12 ` Phillip Lord
2016-08-30 16:06 ` Eli Zaretskii
2016-08-31 11:20 ` Phillip Lord
2016-08-31 14:57 ` Eli Zaretskii
2016-08-30 17:12 ` Alan Mackenzie
2016-08-30 17:27 ` Daniel Colascione
2016-08-30 17:42 ` Eli Zaretskii
2016-08-30 17:46 ` Daniel Colascione
2016-08-30 18:00 ` Eli Zaretskii
2016-08-30 18:04 ` Daniel Colascione
2016-08-30 18:46 ` Eli Zaretskii
2016-08-30 18:58 ` Daniel Colascione
2016-08-30 19:17 ` Eli Zaretskii
2016-08-30 21:46 ` Stefan Monnier
2016-08-31 2:38 ` Eli Zaretskii
2016-08-30 18:27 ` Stefan Monnier
2016-09-01 13:46 ` Eli Zaretskii
2016-08-30 18:01 ` Alan Mackenzie
2016-08-30 18:06 ` Daniel Colascione
2016-08-30 18:17 ` Daniel Colascione
2016-08-30 18:30 ` Alan Mackenzie
2016-08-30 18:32 ` Daniel Colascione
2016-08-30 18:47 ` Alan Mackenzie
2016-08-30 18:55 ` Daniel Colascione
2016-08-30 19:14 ` Alan Mackenzie
2016-08-30 20:34 ` Stefan Monnier
2016-08-30 20:53 ` Alan Mackenzie
2016-08-30 21:37 ` Stefan Monnier [this message]
2016-08-30 18:36 ` Stefan Monnier
2016-08-30 18:22 ` Stefan Monnier
2016-08-30 18:00 ` Stefan Monnier
2016-08-30 17:27 ` Eli Zaretskii
2016-08-30 17:42 ` Alan Mackenzie
2016-08-30 17:53 ` Eli Zaretskii
2016-08-30 18:16 ` Alan Mackenzie
2016-08-30 18:51 ` Eli Zaretskii
2016-08-30 19:00 ` Alan Mackenzie
2016-08-30 18:14 ` Stefan Monnier
2016-09-01 21:25 ` Davis Herring
2016-09-02 7:26 ` Eli Zaretskii
2016-08-28 22:36 ` Stefan Monnier
2016-08-30 13:30 ` Phillip Lord
2016-08-30 13:39 ` Stefan Monnier
2016-08-31 11:04 ` Phillip Lord
2016-08-30 15:47 ` Eli Zaretskii
2016-08-30 16:01 ` Stefan Monnier
2016-08-30 16:58 ` Eli Zaretskii
2016-08-30 17:57 ` Stefan Monnier
2016-08-31 11:17 ` Phillip Lord
2016-08-31 11:12 ` Phillip Lord
2016-08-30 16:23 ` Daniel Colascione
2016-08-30 16:53 ` Eli Zaretskii
2016-08-02 19:00 ` Unbalanced change hooks (part 2) Alan Mackenzie
2016-08-02 19:25 ` Eli Zaretskii
2016-08-07 21:16 ` Alan Mackenzie
2016-08-08 15:38 ` Eli Zaretskii
2016-08-08 19:56 ` Stefan Monnier
2016-08-08 20:16 ` Alan Mackenzie
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
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=jwvh9a2rlyv.fsf-monnier+gmane.emacs.devel@gnu.org \
--to=monnier@iro.umontreal.ca \
--cc=emacs-devel@gnu.org \
/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 external index
https://git.savannah.gnu.org/cgit/emacs.git
https://git.savannah.gnu.org/cgit/emacs/org-mode.git
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.