On 21/01/14 14:14 -0500, Tim Shen wrote:
My conclusion is actually based on Boost.Regex's behavior. boost::basic_regex::mark_count() returns 1 with nosubs flag. Note that boost::basic_regex::mark_count() == std::basic_regex::mark_count() + 1, because std does not count the 0th capture (the whole regex) in. libc++'s mark_count returns 0 as well.
OK, thanks for confirming that. In that case your patch is OK to commit. I'll raise a defect report against the standard as I don't think the specification of nosubs is clear. If that's what it means then it should be defined in terms of "marked sub-expressions" not just by stating the effect it has on match_results objects.
