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// Copyright (C) 2005, Fernando Luis Cacciola Carballal.
//
// Use, modification, and distribution is subject to the Boost Software
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
//
// See http://www.boost.org/libs/optional for documentation.
//
// You are welcome to contact the author at:
// fernando_cacciola@hotmail.com
//
#ifndef BOOST_OPTIONAL_OPTIONAL_IO_FLC_19NOV2002_HPP
#define BOOST_OPTIONAL_OPTIONAL_IO_FLC_19NOV2002_HPP
#include <istream>
#include <ostream>
#include <boost/none.hpp>
#include <boost/assert.hpp>
#include "boost/optional/optional.hpp"
#include "boost/utility/value_init.hpp"
namespace boost
{
template<class CharType, class CharTrait, class T>
inline
std::basic_ostream<CharType, CharTrait>&
operator<<(std::basic_ostream<CharType, CharTrait>& out, optional<T> const& v)
{
if ( out.good() )
{
if ( !v )
out << "--" ;
else out << ' ' << *v ;
}
return out;
}
template<class CharType, class CharTrait, class T>
inline
std::basic_istream<CharType, CharTrait>&
operator>>(std::basic_istream<CharType, CharTrait>& in, optional<T>& v)
{
if (in.good())
{
int d = in.get();
if (d == ' ')
{
T x;
in >> x;
v = x;
}
else
{
if (d == '-')
{
d = in.get();
if (d == '-')
{
v = none;
return in;
}
}
in.setstate( std::ios::failbit );
}
}
return in;
}
} // namespace boost
#endif
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