// 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/lib/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

#if defined __GNUC__

#  if (__GNUC__ == 2 && __GNUC_MINOR__ <= 97) 

#    define BOOST_OPTIONAL_NO_TEMPLATED_STREAMS

#  endif

#endif // __GNUC__

#if defined BOOST_OPTIONAL_NO_TEMPLATED_STREAMS

#  include <iostream>

#else 

#  include <istream>

#  include <ostream>

#endif  

#include "boost/optional/optional.hpp"

#include "boost/utility/value_init.hpp"

namespace boost

{

#if defined (BOOST_NO_TEMPLATED_STREAMS)

template<class T>

inline std::ostream& operator<<(std::ostream& out, optional<T> const& v)

#else

template<class CharType, class CharTrait, class T>

inline

std::basic_ostream<CharType, CharTrait>&

operator<<(std::basic_ostream<CharType, CharTrait>& out, optional<T> const& v)

#endif

{

  if ( out.good() )

  {

    if ( !v )

         out << "--" ;

    else out << ' ' << *v ;

  }

  return out;

}

#if defined (BOOST_NO_TEMPLATED_STREAMS)

template<class T>

inline std::istream& operator>>(std::istream& in, optional<T>& v)

#else

template<class CharType, class CharTrait, class T>

inline

std::basic_istream<CharType, CharTrait>&

operator>>(std::basic_istream<CharType, CharTrait>& in, optional<T>& v)

#endif

{

  if ( in.good() )

  {

    int d = in.get();

    if ( d == ' ' )

    {

      T x ;

      in >> x;

      v = x ;

    }

    else

      v = optional<T>() ;

  }

  return in;

}

} // namespace boost

#endif