lyx_mirror/boost/boost/ref.hpp
Lars Gullik Bjønnes e1644a68eb update boost to pre-1.30.0
git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@6319 a592a061-630c-0410-9148-cb99ea01b6c8
2003-03-03 15:53:48 +00:00

164 lines
3.2 KiB
C++

#ifndef BOOST_REF_HPP_INCLUDED
# define BOOST_REF_HPP_INCLUDED
# if _MSC_VER+0 >= 1020
# pragma once
# endif
# include <boost/config.hpp>
# include <boost/utility/addressof.hpp>
# include <boost/mpl/bool.hpp>
//
// ref.hpp - ref/cref, useful helper functions
//
// Copyright (C) 1999, 2000 Jaakko Järvi (jaakko.jarvi@cs.utu.fi)
// Copyright (C) 2001, 2002 Peter Dimov
// Copyright (C) 2002 David Abrahams
//
// Permission to copy, use, modify, sell and distribute this software
// is granted provided this copyright notice appears in all copies.
// This software is provided "as is" without express or implied
// warranty, and with no claim as to its suitability for any purpose.
//
// See http://www.boost.org/libs/bind/ref.html for documentation.
//
namespace boost
{
template<class T> class reference_wrapper
{
public:
typedef T type;
#if defined(BOOST_MSVC) && (BOOST_MSVC < 1300)
explicit reference_wrapper(T& t): t_(&t) {}
#else
explicit reference_wrapper(T& t): t_(addressof(t)) {}
#endif
operator T& () const { return *t_; }
T& get() const { return *t_; }
T* get_pointer() const { return t_; }
private:
T* t_;
};
# if defined(__BORLANDC__) && (__BORLANDC__ <= 0x570)
# define BOOST_REF_CONST
# else
# define BOOST_REF_CONST const
# endif
template<class T> inline reference_wrapper<T> BOOST_REF_CONST ref(T & t)
{
return reference_wrapper<T>(t);
}
template<class T> inline reference_wrapper<T const> BOOST_REF_CONST cref(T const & t)
{
return reference_wrapper<T const>(t);
}
# undef BOOST_REF_CONST
# ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
template<typename T>
class is_reference_wrapper
: public mpl::false_
{
};
template<typename T>
class is_reference_wrapper<reference_wrapper<T> >
: public mpl::true_
{
};
template<typename T>
class unwrap_reference
{
public:
typedef T type;
};
template<typename T>
class unwrap_reference<reference_wrapper<T> >
{
public:
typedef T type;
};
# else // no partial specialization
} // namespace boost
#include <boost/type.hpp>
namespace boost
{
namespace detail
{
typedef char (&yes_reference_wrapper_t)[1];
typedef char (&no_reference_wrapper_t)[2];
no_reference_wrapper_t is_reference_wrapper_test(...);
template<typename T>
yes_reference_wrapper_t is_reference_wrapper_test(type< reference_wrapper<T> >);
template<bool wrapped>
struct reference_unwrapper
{
template <class T>
struct apply
{
typedef T type;
};
};
template<>
struct reference_unwrapper<true>
{
template <class T>
struct apply
{
typedef typename T::type type;
};
};
}
template<typename T>
class is_reference_wrapper
{
public:
BOOST_STATIC_CONSTANT(
bool, value = (
sizeof(detail::is_reference_wrapper_test(type<T>()))
== sizeof(detail::yes_reference_wrapper_t)));
typedef ::boost::mpl::bool_<value> type;
};
template <typename T>
class unwrap_reference
: public detail::reference_unwrapper<
is_reference_wrapper<T>::value
>::template apply<T>
{};
# endif // BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
} // namespace boost
#endif // #ifndef BOOST_REF_HPP_INCLUDED