[Boost-users] [xpressive] accessing nested results from a submatch

Hi, Is there a way to access nested results associated with a submatch? For example: sregex A = some_xpr; sregex B = (s1 = A) >> other_xpr >> (s2 = A); smatch m; regex_match(str, m, B); I know I can get a list of all the nested matches inside m, and I can filter it down by regex id to matches for A, but is there a way to get, say, "the nested matches for A that occurred inside the sub-match s2" without necessarily knowing what is the position of that in the list of all nested matches for A? Thanks, Nate