Christopher Kohlhoff wrote:
Hi Eric, Scott,
Sorry if this is getting a bit off-topic for the xpressive review...
Mmm, drifting a bit, perhaps, but it's worth clearing this up.
I'm not totally familiar with the xpressive API, but as far as I understand the regex APIs (even with iterators) are not sufficient for clean integration with async I/O.
What you need is a stateful decoder that you can feed data to as you receive it off the wire, and it tells you when it is done, or when it needs you to feed it more data.
What you are describing, at least in regex terms, is a partial match. Ordinarily, a regex match will give you a "yes" or a "no" answer. With a partial match, you can get a "maybe" if the input sequence is exhausted before the regex state machine has reached its final state. Boost.Regex and xpressive both support partial matches via the match_partial switch, which is documented (for Boost.Regex) here: http://boost.org/libs/regex/doc/partial_matches.html Note that TR1 regex does not support partial matches, for the simple reason that we weren't able to come up with satisfactory standardese in time. -- Eric Niebler Boost Consulting www.boost-consulting.com