[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Emacs-diffs] Changes to emacs/lispref/searching.texi [lexbind]
From: |
Miles Bader |
Subject: |
[Emacs-diffs] Changes to emacs/lispref/searching.texi [lexbind] |
Date: |
Wed, 06 Oct 2004 01:42:51 -0400 |
Index: emacs/lispref/searching.texi
diff -c emacs/lispref/searching.texi:1.39.2.8
emacs/lispref/searching.texi:1.39.2.9
*** emacs/lispref/searching.texi:1.39.2.8 Fri Jul 23 04:42:21 2004
--- emacs/lispref/searching.texi Wed Oct 6 05:23:53 2004
***************
*** 975,980 ****
--- 975,1006 ----
@end example
@end defun
+ @defun looking-back regexp &optional limit
+ This function returns @code{t} if @var{regexp} matches text before
+ point, ending at point, and @code{nil} otherwise.
+
+ Because regular expression matching works only going forward, this is
+ implemented by searching backwards from point for a match that ends at
+ point. That can be quite slow if it has to search a long distance.
+ You can bound the time required by specifying @var{limit}, which says
+ not to search before @var{limit}. In this case, the match that is
+ found must begin at or after @var{limit}.
+
+ @example
+ @group
+ ---------- Buffer: foo ----------
+ I read "@point{}The cat in the hat
+ comes back" twice.
+ ---------- Buffer: foo ----------
+
+ (looking-back "read \"" 3)
+ @result{} t
+ (looking-back "read \"" 4)
+ @result{} nil
+ @end group
+ @end example
+ @end defun
+
@node POSIX Regexps
@section POSIX Regular Expression Searching
- [Emacs-diffs] Changes to emacs/lispref/searching.texi [lexbind],
Miles Bader <=