From: Suvayu Ali <fatkasuvayu+linux@gmail.com>
To: Emacs help <help-gnu-emacs@gnu.org>
Subject: Question about string-match and match-string
Date: Wed, 17 Jul 2013 10:17:04 +0200 [thread overview]
Message-ID: <20130717081704.GB16899@kuru.dyndns-at-home.com> (raw)
Hi,
I was writing a filter for Org mode and came across this confusion. I
want to parse a string with LaTeX code and delete matching
sub-expressions. As a test I tried this:
(let ((test "\\section{Heading{ignoreheading}}\nText\n"))
(string-match "\\(\\\\\\\\section{.+{ignoreheading}}\\\\n\\)\\(.+\\)" test)
(match-substitute-replacement "" t nil test 1)
)
But evaluating the above I get the following backtrace.
Debugger entered--Lisp error: (args-out-of-range -1 -1)
replace-match("" t nil "{" 1)
match-substitute-replacement("" t nil "\\section{Heading{ignoreheading}}\nText\n" 1)
(let ((test "\\section{Heading{ignoreheading}}\nText\n")) (string-match "\\(\\\\\\\\section{.+{ignoreheading}}\\\\n\\)\\(.+\\)" test) (match-substitute-replacement "" t nil test 1))
eval((let ((test "\\section{Heading{ignoreheading}}\nText\n")) (string-match "\\(\\\\\\\\section{.+{ignoreheading}}\\\\n\\)\\(.+\\)" test) (match-substitute-replacement "" t nil test 1)) nil)
eval-last-sexp-1(nil)
eval-last-sexp(nil)
call-interactively(eval-last-sexp nil nil)
command-execute(eval-last-sexp)
I do not understand the error at all, since if I insert something like
(prin1 test) before the (match-substitute-replacement ..) in my example
code, I get the expected output (the value of test as bound by let).
Where am I going wrong?
Thank you for any guidance.
PS: I'm also not very clear why we need 4 \-s in the regex to match a
single \ in the string. I came up with it by trial and error with the
regexp-builder. Any explanation about that would also be great.
--
Suvayu
Open source is the future. It sets us free.
next reply other threads:[~2013-07-17 8:17 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-07-17 8:17 Suvayu Ali [this message]
2013-07-17 8:35 ` Question about string-match and match-string Suvayu Ali
2013-07-17 8:44 ` Rasmus
2013-07-17 8:55 ` Suvayu Ali
2013-07-18 8:00 ` Julien Cubizolles
2013-07-18 8:33 ` Rasmus
2013-07-20 15:26 ` Julien Cubizolles
2013-07-20 22:25 ` Rasmus
2013-07-21 0:41 ` Rasmus
2013-07-21 8:15 ` Julien Cubizolles
2013-07-17 8:53 ` Nicolas Richard
2013-07-17 10:02 ` Suvayu Ali
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=20130717081704.GB16899@kuru.dyndns-at-home.com \
--to=fatkasuvayu+linux@gmail.com \
--cc=help-gnu-emacs@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.
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).