nocollate = 0, // don't use locale specific collation (deprecated)
collate = 1 << 21, // use locale specific collation
nosubs = 1 << 22, // don't mark sub-expressions
+ save_subexpression_location = 1 << 23, // save subexpression locations
+ no_empty_expressions = 1 << 24, // no empty expressions allowed
optimize = 0, // not really supported
mod_x = ::boost::regbase::mod_x,
mod_s = ::boost::regbase::mod_s,
no_mod_s = ::boost::regbase::no_mod_s,
+ save_subexpression_location = ::boost::regbase::save_subexpression_location,
+ no_empty_expressions = ::boost::regbase::no_empty_expressions,
basic = ::boost::regbase::basic,
extended = ::boost::regbase::extended,