[Boost-users] Serialization problem with polymorphic archives and std::string

From: Michael Sperber (sperber_at_[hidden])
Date: 2006-02-22 06:01:58

Hi there,

I'm trying to convert a piece of code from templated archives to
polymorphic ones, and am running into trouble when serializing
std::string.  Either I get an error message saying that std::string
has no serialize member function, or I get the attached message.

The relevant code is this:

---snip---
#include <boost/serialization/serialization.hpp>

#include <boost/archive/polymorphic_iarchive.hpp>
#include <boost/archive/polymorphic_oarchive.hpp>

void
mtime::serialize(boost::archive::polymorphic_iarchive& ar,
                 const unsigned int file_version)
{
  std::string iso;
  ar & boost::serialization::make_nvp("iso_time", iso);
  set_from_iso_string(iso);
}

void
mtime::serialize(boost::archive::polymorphic_oarchive& ar,
                 const unsigned int file_version)
{
  std::string iso =3D to_iso_string();
  ar & boost::serialization::make_nvp("iso_time", iso);
}
---snip---

Am I missing something obvious?  Are certain types not directly
supported for serialization via polymorphic archives?  Any help would
be much appreciated.
-- 
Cheers =8-} Mike
Friede, Völkerverständigung und überhaupt blabla
--=-=-=
g++ -g -Wall  -I /afs/informatik.uni-tuebingen.de/i386_fbsd54/boost-1.33.1/include/boost-1_33_1  -c -o mtime.o mtime.cpp
/afs/informatik.uni-tuebingen.de/i386_fbsd54/boost-1.33.1/include/boost-1_33_1/boost/archive/detail/iserializer.hpp: In constructor `boost::archive::detail::iserializer<Archive, T>::iserializer() [with Archive = boost::archive::polymorphic_iarchive, T = std::basic_string<char, std::char_traits<char>, std::allocator<char> >]':
/afs/informatik.uni-tuebingen.de/i386_fbsd54/boost-1.33.1/include/boost-1_33_1/boost/archive/detail/iserializer.hpp:146:   instantiated from `static boost::archive::detail::iserializer<Archive, T>& boost::archive::detail::iserializer<Archive, T>::instantiate() [with Archive = boost::archive::polymorphic_iarchive, T = std::basic_string<char, std::char_traits<char>, std::allocator<char> >]'
/afs/informatik.uni-tuebingen.de/i386_fbsd54/boost-1.33.1/include/boost-1_33_1/boost/archive/detail/iserializer.hpp:375:   instantiated from `static void boost::archive::detail::load_non_pointer_type<Archive, T>::load_standard::invoke(Archive&, T&) [with Archive = boost::archive::polymorphic_iarchive, T = std::basic_string<char, std::char_traits<char>, std::allocator<char> >]'
/afs/informatik.uni-tuebingen.de/i386_fbsd54/boost-1.33.1/include/boost-1_33_1/boost/archive/detail/iserializer.hpp:425:   instantiated from `static void boost::archive::detail::load_non_pointer_type<Archive, T>::invoke(Archive&, T&) [with Archive = boost::archive::polymorphic_iarchive, T = std::basic_string<char, std::char_traits<char>, std::allocator<char> >]'
/afs/informatik.uni-tuebingen.de/i386_fbsd54/boost-1.33.1/include/boost-1_33_1/boost/archive/detail/iserializer.hpp:572:   instantiated from `void boost::archive::load(Archive&, T&) [with Archive = boost::archive::polymorphic_iarchive, T = std::basic_string<char, std::char_traits<char>, std::allocator<char> >]'
/afs/informatik.uni-tuebingen.de/i386_fbsd54/boost-1.33.1/include/boost-1_33_1/boost/archive/polymorphic_iarchive.hpp:127:   instantiated from `void boost::archive::polymorphic_iarchive::load_override(const boost::serialization::nvp<T>&, int) [with T = std::string]'
/afs/informatik.uni-tuebingen.de/i386_fbsd54/boost-1.33.1/include/boost-1_33_1/boost/archive/detail/interface_iarchive.hpp:76:   instantiated from `Archive& boost::archive::detail::interface_iarchive<Archive>::operator>>(T&) [with T = const boost::serialization::nvp<std::string>, Archive = boost::archive::polymorphic_iarchive]'
/afs/informatik.uni-tuebingen.de/i386_fbsd54/boost-1.33.1/include/boost-1_33_1/boost/archive/detail/interface_iarchive.hpp:83:   instantiated from `Archive& boost::archive::detail::interface_iarchive<Archive>::operator&(T&) [with T = const boost::serialization::nvp<std::string>, Archive = boost::archive::polymorphic_iarchive]'
mtime.cpp:36:   instantiated from here
/afs/informatik.uni-tuebingen.de/i386_fbsd54/boost-1.33.1/include/boost-1_33_1/boost/archive/detail/iserializer.hpp:115: error: incomplete type `boost::serialization::extended_type_info_null<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >' used in nested name specifier
/afs/informatik.uni-tuebingen.de/i386_fbsd54/boost-1.33.1/include/boost-1_33_1/boost/archive/detail/oserializer.hpp: In constructor `boost::archive::detail::oserializer<Archive, T>::oserializer() [with Archive = boost::archive::polymorphic_oarchive, T = std::basic_string<char, std::char_traits<char>, std::allocator<char> >]':
/afs/informatik.uni-tuebingen.de/i386_fbsd54/boost-1.33.1/include/boost-1_33_1/boost/archive/detail/oserializer.hpp:135:   instantiated from `static boost::archive::detail::oserializer<Archive, T>& boost::archive::detail::oserializer<Archive, T>::instantiate() [with Archive = boost::archive::polymorphic_oarchive, T = std::basic_string<char, std::char_traits<char>, std::allocator<char> >]'
/afs/informatik.uni-tuebingen.de/i386_fbsd54/boost-1.33.1/include/boost-1_33_1/boost/archive/detail/oserializer.hpp:264:   instantiated from `static void boost::archive::detail::save_non_pointer_type<Archive, T>::save_standard::invoke(Archive&, const T&) [with Archive = boost::archive::polymorphic_oarchive, T = std::basic_string<char, std::char_traits<char>, std::allocator<char> >]'
/afs/informatik.uni-tuebingen.de/i386_fbsd54/boost-1.33.1/include/boost-1_33_1/boost/archive/detail/oserializer.hpp:322:   instantiated from `static void boost::archive::detail::save_non_pointer_type<Archive, T>::invoke(Archive&, const T&) [with Archive = boost::archive::polymorphic_oarchive, T = std::basic_string<char, std::char_traits<char>, std::allocator<char> >]'
/afs/informatik.uni-tuebingen.de/i386_fbsd54/boost-1.33.1/include/boost-1_33_1/boost/archive/detail/oserializer.hpp:536:   instantiated from `void boost::archive::save(Archive&, const T&) [with Archive = boost::archive::polymorphic_oarchive, T = std::basic_string<char, std::char_traits<char>, std::allocator<char> >]'
/afs/informatik.uni-tuebingen.de/i386_fbsd54/boost-1.33.1/include/boost-1_33_1/boost/archive/polymorphic_oarchive.hpp:128:   instantiated from `void boost::archive::polymorphic_oarchive::save_override(const boost::serialization::nvp<T>&, int) [with T = std::string]'
/afs/informatik.uni-tuebingen.de/i386_fbsd54/boost-1.33.1/include/boost-1_33_1/boost/archive/detail/interface_oarchive.hpp:78:   instantiated from `Archive& boost::archive::detail::interface_oarchive<Archive>::operator<<(T&) [with T = const boost::serialization::nvp<std::string>, Archive = boost::archive::polymorphic_oarchive]'
/afs/informatik.uni-tuebingen.de/i386_fbsd54/boost-1.33.1/include/boost-1_33_1/boost/archive/detail/interface_oarchive.hpp:86:   instantiated from `Archive& boost::archive::detail::interface_oarchive<Archive>::operator&(T&) [with T = const boost::serialization::nvp<std::string>, Archive = boost::archive::polymorphic_oarchive]'
mtime.cpp:46:   instantiated from here
/afs/informatik.uni-tuebingen.de/i386_fbsd54/boost-1.33.1/include/boost-1_33_1/boost/archive/detail/oserializer.hpp:108: error: incomplete type `boost::serialization::extended_type_info_null<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >' used in nested name specifier
make: *** [mtime.o] Error 1
Compilation exited abnormally with code 2 at Wed Feb 22 11:56:36
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