There are results from of performance benchmarks of static xpressive vs. dynamic xpressive vs. Boost.Regex in the Appendix of xpressive's documentation. You must have missed it. See:
Sorry, yes I missed the appendices.
http://boost-sandbox.sf.net/libs/xpressive/doc/html/xpressive/perf.html
In short, xpressive comes out consistently ahead of Boost.Regex on short matches, and roughly on par for longer matches (with wide variation).
Interesting. This left me with two questions: 1. Why is dynamic quicker than static xpressive on some expressions? 2. Why is boost::regex quicker on longer strings? Something to do with buffering or dynamic memory usage? I thought "Huck[[:alpha:]]+" (expressive twice as quick) vs. "[[:alpha:]]+ing" (boost::regex twice as quick) was very curious. Is this due to some design decision, or just something waiting to be optimized?
Agreed. FYI, "_" matches any one character. ~_n matches any character that is not '\n'. I also need to describe _ln which matches a logical newline (eg., "\n" or "\r" or "\r\n" or other line separators) and ~_ln which matches any one character that is not a line separator.
_ln sounds useful. Is that in perl/PCRE ? Darren