[#getting_started_39]

  #include <boost/metaparse/foldl_reject_incomplete_start_with_parser.hpp>
  struct plus_exp5 : foldl_reject_incomplete_start_with_parser< sequence<one_of<plus_token, minus_token>, mult_exp6>, mult_exp6, boost::mpl::quote2<binary_op> > {};
  using exp_parser22 = build_parser<plus_exp5>;