From: "Lennart Borgman (gmail)" <lennart.borgman@gmail.com>
To: Alan Mackenzie <acm@muc.de>
Cc: emacs-devel@gnu.org
Subject: Re: Idea for syntax-ppss. Is it new? Could it be any good?
Date: Sun, 27 Jul 2008 02:36:26 +0200 [thread overview]
Message-ID: <488BC30A.7010009@gmail.com> (raw)
In-Reply-To: <20080726214429.GB3623@muc.de>
Alan Mackenzie wrote:
> Hi, Emacs,
>
> Looking at the doc string for syntax-ppss, it seems this could be _very_
> useful in a certain body of code I'm responsible for. That body of code
> has a lot of heuristics that determine whether point is within a
> string/comment, and some of these are not watertight (such as hard-coded
> limits on comment sizes to achieve speed). Basically, they're a PITA.
> syntax-ppss, if it was guaranteed watertight, could remove the gnawing
> uncertainty from much of the code.
>
> However, the manual documents limitations on syntax-ppss's functionality.
>
> How about reimplementing it thusly?: The current syntax would be cached
> for positions at every N bytes (where N would be, perhaps 1024, possibly
> 8192). A call to syntax-ppss would simply call parse-partial-sexp from
> the latest valid cached position, filling out the cache as it goes. Any
> buffer change would invalidate cached values for N > POS.
There are some defadvices for syntax-ppss and cousins in mumamo.el that
does something like this. This is needed in multi major mode buffers if
the normal font lock routines is used there.
I do not exactly do what you propose and a bit more is needed (for
mumamo). I think however that any solution should take the need for
multi major modes into account.
> I envisage coding this in C rather than Lisp. There would be some
> complications to do with making sure the syntax table isn't tampered
> with, and so on. This code would surely be fast and reliable.
>
> Obviously I'm not proposing this for the pending release, but what do
> people think about the idea?
>
next prev parent reply other threads:[~2008-07-27 0:36 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-07-26 21:44 Idea for syntax-ppss. Is it new? Could it be any good? Alan Mackenzie
2008-07-27 0:36 ` Lennart Borgman (gmail) [this message]
2008-07-27 1:34 ` Stefan Monnier
2008-07-27 14:50 ` Alan Mackenzie
2008-07-27 15:51 ` Stefan Monnier
2008-07-27 19:20 ` Alan Mackenzie
2008-07-27 20:17 ` Stefan Monnier
2008-07-28 2:27 ` Richard M Stallman
2008-07-28 4:08 ` Stefan Monnier
2008-07-28 21:47 ` Richard M Stallman
2008-08-31 8:37 ` Better parse-partial-sexp; multiple major modes (was: Idea for syntax-ppss) Daniel Colascione
2008-08-31 15:02 ` Better parse-partial-sexp; multiple major modes Lennart Borgman (gmail)
2008-09-01 6:10 ` Better parse-partial-sexp; multiple major modes (was: Idea for syntax-ppss) Richard M. Stallman
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=488BC30A.7010009@gmail.com \
--to=lennart.borgman@gmail.com \
--cc=acm@muc.de \
--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.