Re: [Boost-users] [serialization]Nans and infinity in wide xml archive

4 Jul 2017

      On 7/4/17 2:48 AM, Elizabeta via Boost-users wrote:
...
Hi Robert
I did template specialization of basic_text_iprimitive::load for double, and
it works with visual studio 2010 compiler. Do you see something problematic
with this code
namespace boost {
     namespace archive {
         template<> template<>
         void basic_text_iprimitive< std::basic_istream> >::load<double>(double& t)
         {
             if (!is.fail())
             {
                 std::wstring s;
                 getline(is, s, L'<');
                 is.putback(L'<');
int index = s.find(L"IND");
                 if (index != -1)
                 {
                     t = std::numeric_limits<double>::quiet_NaN();
                     return;
                 }
index = s.find(L"NAN");
                 if (index != -1)
                 {
                     t = std::numeric_limits<double>::quiet_NaN();
                     return;
                 }
index = s.find(L"INF");
                 if (index != -1)
                 {
                     t = std::numeric_limits<double>::infinity();
                     return;
                 }
t = std::stod(s);
                 return;
             }
boost::serialization::throw_exception(
                 archive_exception(archive_exception::input_stream_error)
                 );
         }
}
}
Hmmm - very clever.  I have to say the specialization of just one member 
function is something that would never have occurred to me.

I would wonder though.  I'm not sure that the Nan literals are standard. 
  I also don't trust them to be portable.  Also to me it's a problem 
with stream i/o rather than serialization itself.  So my instinct would 
have been to maybe make a custom manipulator or something like that. But 
still, you've got a solution which looks like it will work well for your 
needs so good luck with this.

Robert Ramey