#ifndef BOOST_PFTO_HPP

#define BOOST_PFTO_HPP

// MS compatible compilers support #pragma once

#if defined(_MSC_VER) && (_MSC_VER >= 1020)

# pragma once

#endif

/////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8

// pfto.hpp: workarounds for compilers which have problems supporting

// Partial Function Template Ordering (PFTO).

// (C) Copyright 2002 Robert Ramey - http://www.rrsd.com . 

// 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 for updates, documentation, and revision history.

// PFTO version is used to specify the last argument of certain functions

// Function it is used to support  compilers that fail to support correct Partial 

// Template Ordering

#include <boost/config.hpp>

// some compilers can use an exta argument and use function overloading

// to choose desired function.  This extra argument is long in the default

// function implementation and int for the rest.  The function is called

// with an int argument.  This first attempts to match functions with an

// int argument before the default one (with a long argument).  This is

// known to function with VC 6.0. On other compilers this fails (Borland)

// or causes other problems (GCC).  note: this 

#if defined(BOOST_NO_FUNCTION_TEMPLATE_ORDERING)

    #define BOOST_PFTO long

#else

    #define BOOST_PFTO

#endif

// here's another approach.  Rather than use a default function - make sure

// there is no default at all by requiring that all function invocations

// have a "wrapped" argument type.  This solves a problem with VC 6.0

// (and perhaps others) while implementing templated constructors.

namespace boost {

template<class T>

struct pfto_wrapper {

    const T & t;

    operator const T & (){

        return t;

    }

    pfto_wrapper (const T & rhs) : t(rhs) {}

};

template<class T>

pfto_wrapper<T> make_pfto_wrapper(const T & t, BOOST_PFTO int){

    return pfto_wrapper<T>(t);

}

template<class T>

pfto_wrapper<T> make_pfto_wrapper(const pfto_wrapper<T> & t, int){

    return t;

}

} // namespace boost

#ifdef BOOST_NO_FUNCTION_TEMPLATE_ORDERING

    #define BOOST_PFTO_WRAPPER(T) boost::pfto_wrapper<T>

    #define BOOST_MAKE_PFTO_WRAPPER(t) boost::make_pfto_wrapper(t, 0)

#else

    #define BOOST_PFTO_WRAPPER(T) T

    #define BOOST_MAKE_PFTO_WRAPPER(t) t

#endif

#endif // BOOST_PFTO_HPP