sl@0: #ifndef BOOST_PFTO_HPP
sl@0: #define BOOST_PFTO_HPP
sl@0: 
sl@0: // MS compatible compilers support #pragma once
sl@0: #if defined(_MSC_VER) && (_MSC_VER >= 1020)
sl@0: # pragma once
sl@0: #endif
sl@0: 
sl@0: /////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8
sl@0: // pfto.hpp: workarounds for compilers which have problems supporting
sl@0: // Partial Function Template Ordering (PFTO).
sl@0: 
sl@0: // (C) Copyright 2002 Robert Ramey - http://www.rrsd.com . 
sl@0: // Use, modification and distribution is subject to the Boost Software
sl@0: // License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
sl@0: // http://www.boost.org/LICENSE_1_0.txt)
sl@0: 
sl@0: //  See http://www.boost.org for updates, documentation, and revision history.
sl@0: // PFTO version is used to specify the last argument of certain functions
sl@0: // Function it is used to support  compilers that fail to support correct Partial 
sl@0: // Template Ordering
sl@0: #include <boost/config.hpp>
sl@0: 
sl@0: // some compilers can use an exta argument and use function overloading
sl@0: // to choose desired function.  This extra argument is long in the default
sl@0: // function implementation and int for the rest.  The function is called
sl@0: // with an int argument.  This first attempts to match functions with an
sl@0: // int argument before the default one (with a long argument).  This is
sl@0: // known to function with VC 6.0. On other compilers this fails (Borland)
sl@0: // or causes other problems (GCC).  note: this 
sl@0: 
sl@0: #if defined(BOOST_NO_FUNCTION_TEMPLATE_ORDERING)
sl@0:     #define BOOST_PFTO long
sl@0: #else
sl@0:     #define BOOST_PFTO
sl@0: #endif
sl@0: 
sl@0: // here's another approach.  Rather than use a default function - make sure
sl@0: // there is no default at all by requiring that all function invocations
sl@0: // have a "wrapped" argument type.  This solves a problem with VC 6.0
sl@0: // (and perhaps others) while implementing templated constructors.
sl@0: 
sl@0: namespace boost {
sl@0: 
sl@0: template<class T>
sl@0: struct pfto_wrapper {
sl@0:     const T & t;
sl@0:     operator const T & (){
sl@0:         return t;
sl@0:     }
sl@0:     pfto_wrapper (const T & rhs) : t(rhs) {}
sl@0: };
sl@0: 
sl@0: template<class T>
sl@0: pfto_wrapper<T> make_pfto_wrapper(const T & t, BOOST_PFTO int){
sl@0:     return pfto_wrapper<T>(t);
sl@0: }
sl@0: 
sl@0: template<class T>
sl@0: pfto_wrapper<T> make_pfto_wrapper(const pfto_wrapper<T> & t, int){
sl@0:     return t;
sl@0: }
sl@0: 
sl@0: } // namespace boost
sl@0: 
sl@0: #ifdef BOOST_NO_FUNCTION_TEMPLATE_ORDERING
sl@0:     #define BOOST_PFTO_WRAPPER(T) boost::pfto_wrapper<T>
sl@0:     #define BOOST_MAKE_PFTO_WRAPPER(t) boost::make_pfto_wrapper(t, 0)
sl@0: #else
sl@0:     #define BOOST_PFTO_WRAPPER(T) T
sl@0:     #define BOOST_MAKE_PFTO_WRAPPER(t) t
sl@0: #endif
sl@0: 
sl@0: #endif // BOOST_PFTO_HPP