Limbo Peng <iwi...@gmail.com> writes:
> I'm confused by the result of string-match:
>
> (string-match "[0-9]+" "abc123zzz") ;; this works, giving result: #
> ("abc123zzz" (3 . 6))
> (string-match "\\d+" "abc123zzz") ;; this doesn't work, giving result:
> #f
>
> Why isn't the "\\d+" syntax (character classes) supported?
Regular expression syntax is not standardized, and there are several
different variants. The "\d" syntax for character classes is a
non-standard perl extension, and is not supported by Guile.
Guile supports the POSIX regexp syntax, whose character classes look
like this:
(string-match "[[:digit:]]+" "abc123zzz")
=> #("abc123zzz" (3 . 6))
For more information see:
http://www.gnu.org/software/guile/manual/html_node/Regular-Expressions.html
http://www.gnu.org/software/emacs/manual/html_node/emacs/Regexps.html
http://www.gnu.org/software/emacs/manual/html_node/elisp/Char-Classes.html
Mark
