boost::xpressive::_n — Matches a literal newline character, '\n'.
// In header: <boost/xpressive/regex_primitives.hpp> proto::terminal< char >::type const _n;
'_n' matches a single newline character, '\n'. Use ~_n to match a character that is not a newline.
~_n is like '.' in perl without the /s modifier.
![[Note]](../../../../doc/src/images/note.png)