From: "Mattias Engdegård" <mattiase@acm.org>
To: Eli Zaretskii <eliz@gnu.org>
Cc: Paul Eggert <eggert@cs.ucla.edu>, emacs-devel <emacs-devel@gnu.org>
Subject: Re: Returning argument string (regexp-quote)
Date: Wed, 25 Sep 2019 15:41:28 +0200 [thread overview]
Message-ID: <4FAEE347-0F67-426F-AA0D-3DB15E3907DC@acm.org> (raw)
In-Reply-To: <83impho4s8.fsf@gnu.org>
[-- Attachment #1: Type: text/plain, Size: 829 bytes --]
24 sep. 2019 kl. 21.47 skrev Eli Zaretskii <eliz@gnu.org>:
>
>> It was responsible for a sizeable portion of local consing in some (non-public) code I was profiling.
>
> "Sizable portion" meaning what, in quantitative terms?
I no longer have the data, maybe 25-40% in the part of the code that I was looking at. It's not uncommon to use 'regexp-quote' just in case.
> I think it should be in NEWS and in the ELisp manual. Doc string
> doesn't necessarily have to say that (although it isn't a catastrophe
> if it does), given its current language.
Thanks -- the updated patch includes NEWS and manual amendments, as well as a slightly simplified condition. The manual didn't actually say anything about a new string being returned (in contrast to 'format' before 3db388b0bf), but a note about it won't hurt.
[-- Attachment #2: 0001-Allow-regexp-quote-to-return-its-argument.patch --]
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From 95dd4e043ea4635c44b656d0145c6bb67408e47f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Mattias=20Engdeg=C3=A5rd?= <mattiase@acm.org>
Date: Mon, 23 Sep 2019 18:56:30 +0200
Subject: [PATCH] Allow regexp-quote to return its argument
* src/search.c (Fregexp_quote): Only allocate a new string if needed.
---
doc/lispref/searching.texi | 3 +++
etc/NEWS | 4 ++++
src/search.c | 10 ++++++----
3 files changed, 13 insertions(+), 4 deletions(-)
diff --git a/doc/lispref/searching.texi b/doc/lispref/searching.texi
index 015871fab0..a4b6533412 100644
--- a/doc/lispref/searching.texi
+++ b/doc/lispref/searching.texi
@@ -1717,6 +1717,9 @@ Regexp Functions
(concat "\\s-" (regexp-quote string) "\\s-"))
@end group
@end example
+
+The returned string may be @var{string} itself if it does not contain
+any special characters.
@end defun
@cindex optimize regexp
diff --git a/etc/NEWS b/etc/NEWS
index 3f7d4894df..49d733b8ac 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -2156,6 +2156,10 @@ valid event type.
---
** The obsolete package xesam.el (since Emacs 24) has been removed.
++++
+** 'regexp-quote' may return its argument string.
+If the argument needs no quoting, it can be returned instead of a copy.
+
\f
* Lisp Changes in Emacs 27.1
diff --git a/src/search.c b/src/search.c
index 1e57d2ecbe..9d95dcbca5 100644
--- a/src/search.c
+++ b/src/search.c
@@ -3138,10 +3138,12 @@ DEFUN ("regexp-quote", Fregexp_quote, Sregexp_quote, 1, 1, 0,
}
Lisp_Object result
- = make_specified_string (temp,
- SCHARS (string) + backslashes_added,
- out - temp,
- STRING_MULTIBYTE (string));
+ = (backslashes_added > 0
+ ? make_specified_string (temp,
+ SCHARS (string) + backslashes_added,
+ out - temp,
+ STRING_MULTIBYTE (string))
+ : string);
SAFE_FREE ();
return result;
}
--
2.21.0 (Apple Git-122)
next prev parent reply other threads:[~2019-09-25 13:41 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-09-24 11:28 Returning argument string (regexp-quote) Mattias Engdegård
2019-09-24 11:49 ` Andreas Schwab
2019-09-24 16:20 ` Eli Zaretskii
2019-09-24 17:44 ` Mattias Engdegård
2019-09-24 18:24 ` Paul Eggert
2019-09-24 19:47 ` Eli Zaretskii
2019-09-25 13:41 ` Mattias Engdegård [this message]
2019-09-25 15:08 ` Eli Zaretskii
2019-09-25 19:55 ` Compilation failure on macOS 10.15 Catalina Zach Pearson
2019-09-25 20:29 ` mituharu
2019-09-25 21:55 ` Zach Pearson
2019-09-25 22:47 ` mituharu
2019-09-25 23:07 ` Zach Pearson
2019-09-25 23:39 ` mituharu
2019-09-27 23:22 ` chad
2019-10-02 3:59 ` Zach Pearson
2019-10-02 4:04 ` YAMAMOTO Mitsuharu
2019-10-02 4:34 ` Zach Pearson
2019-10-02 4:42 ` YAMAMOTO Mitsuharu
2019-10-02 4:43 ` Zach Pearson
2019-10-02 5:00 ` YAMAMOTO Mitsuharu
2019-10-02 5:07 ` Zach Pearson
2019-10-02 7:43 ` Zach Pearson
2019-10-02 15:15 ` Xu Xin
2019-09-26 8:34 ` Robert Pluim
2019-09-26 16:05 ` Zach Pearson
2019-09-26 21:00 ` mituharu
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