Re: [boost] Announcing: xpressive

From: Joel de Guzman (joel_at_[hidden])
Date: 2003-11-16 23:00:51

Eric Niebler <eric_at_[hidden]> wrote:

[snips]

> The inspiration for xpressive comes from Spirit, Boost.Regex, GRETA and
> the Perl 6 regular expression redesign, described by Larry Wall in
> Apocalypse 5 (http://www.perl.com/pub/a/2002/06/04/apo5.html). IMO, the
> Apocalypse is excellent reading for anyone who wants to expand their
> mind about what regular expressions can and should be good for.
> 
> xpressive will differ from Spirit in that it will have backtracking
> semantics. (Spirit has greedy semantics, and does not do backtracking.)
> Also, it will allow rules to be defined at runtime via a string,
> accepted from a user or read from a file.
> 
> The project is still quite small. I have checked the source code into
> the boost sandbox at boost-sandbox/boost/xpressive for anybody who is
> interested.  Joel de Guzman has already expressed interest, and we plan
> to collaborate once he finds some free time.

And BTW, my interest with xpression is to fulfil the idea of having a
modern extremely-fast statically bound Lexer for Spirit. I think xpression 
has all the right ingredients. For instance, even at this early stage,
xpression is already 2x faster than GRETA (which is already an extremely
fast RE engine). If possible, I wish to have a modern lexer at par with or 
faster than RE2C.

-- 
Joel de Guzman
http://www.boost-consulting.com
http://spirit.sf.net