Re: regexp character classes not supported?

[Mark H Weaver]

Limbo Peng <address@hidden> writes:

> On Sat, Dec 29, 2012 at 1:22 AM, Mark H Weaver <address@hidden> wrote:
>
>     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.
>     
>
> Thx...seems that I've been taking such syntax for granted for a long
> time :( 
>
> BTW: I've found a module called pregexp which looks more powerful -
> does it work well in Guile?

First, I should note that any regexp matcher written in Scheme will be
much slower than the one built-in to Guile (which is written in C).

There are some additional problems with pregexp.  It does not appear to
be written with Unicode in mind, and is also written in such a way that
it will probably perform quite poorly on future versions of Guile.

If you'd like a more advanced regexp library, and don't mind the fact
that it will be much slower than Guile's built-in regexps, I recommend
that you look at Alex Shinn's irregex package:

  http://synthcode.com/scheme/irregex/

Irregex is written with Unicode in mind, and supports not only
perl-style regexps, but also Olin Shivers' SRE (Scheme Regular
Expression) syntax, which is a far superior notation for complex
or dynamically-constructed regexps.

  http://www.ccs.neu.edu/home/shivers/papers/sre.txt

    Regards,
      Mark