Struct template plus
boost::proto::plus — A metafunction for generating binary plus expression types,
          a grammar element for matching binary plus expressions, and
          a PrimitiveTransform that dispatches to the
          proto::pass_through<>
          transform.
 
Synopsis
template<typename T, typename U> 
struct plus :  proto::transform< plus<T, U> > {
  
  typedef proto::expr< proto::tag::plus, proto::list2< T, U > >       type;         
  typedef proto::basic_expr< proto::tag::plus, proto::list2< T, U > > proto_grammar;
  
  template<typename Expr, typename State, typename Data> 
  struct impl :  proto::pass_through<plus>::template impl<Expr, State, Data> {
  };
};