Jonathan Turkanis wrote:
I though the system will just work by providing an object with overloaded operator&:
class outputter { public: template<class T> outputter& operator&(const boost::nvp<T>& nvp) { cout << nvp.name() << ":" << nvp.value() << "\n"; } };
class my { template<.....> void serialize(Archive& ar......) { ar & BOOST_SERIALIZATION_NVP(i); } int i; };
Why do you think it's common to don't need all the information? Yes, you probably don't need names for many formatters, but then the operator& will be inline and compiler can optimize passing of the name.
I can imagine wanting to generate a report in xml which involves enumerating the employees working on a project. The employees may be represented by complex objects containing extraneous information such as work history, and only the employee name may be needed. In that case, using a serialize method would be wasteful.
Yes, a bit. OTOH, it would be possible to use the same serialize method to build, once, and member name -> offset map, which can be then used. For a name case you can do: template<class> figure_out_name_offset { figure_out_name_offset operator&(nvp& p) { if (p.name() == "name") { m_address = &p.value() } } std::string* m_address; }; Person p; figure_out_name_offset f; p.serialize(f); unsigned offset = (int)f.m_address - (int)&p;
I don't see why a framework can't provide several options.
I'd rather not see several different options when one is good enough. Many options will confuse users. - Volodya