lyx_mirror/boost/boost/ref.hpp

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#ifndef BOOST_REF_HPP_INCLUDED
#define BOOST_REF_HPP_INCLUDED
// MS compatible compilers support #pragma once
#if defined(_MSC_VER) && (_MSC_VER >= 1020)
# pragma once
#endif
#include <boost/config.hpp>
#include <boost/utility/addressof.hpp>
#include <boost/mpl/bool.hpp>
#include <boost/detail/workaround.hpp>
//
// ref.hpp - ref/cref, useful helper functions
//
// Copyright (C) 1999, 2000 Jaakko Jarvi (jaakko.jarvi@cs.utu.fi)
// Copyright (C) 2001, 2002 Peter Dimov
// Copyright (C) 2002 David Abrahams
//
// Distributed under 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/bind/ref.html for documentation.
//
namespace boost
{
template<class T> class reference_wrapper
{
public:
typedef T type;
#if defined( BOOST_MSVC ) && BOOST_WORKAROUND( BOOST_MSVC, < 1300 )
explicit reference_wrapper(T& t): t_(&t) {}
#else
explicit reference_wrapper(T& t): t_(boost::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__ ) && BOOST_WORKAROUND( __BORLANDC__, BOOST_TESTED_AT(0x581) )
# 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 unwrap_reference
{
public:
typedef T type;
};
# define AUX_REFERENCE_WRAPPER_METAFUNCTIONS_DEF(X) \
template<typename T> \
class is_reference_wrapper< X > \
: public mpl::true_ \
{ \
}; \
\
template<typename T> \
class unwrap_reference< X > \
{ \
public: \
typedef T type; \
}; \
/**/
AUX_REFERENCE_WRAPPER_METAFUNCTIONS_DEF(reference_wrapper<T>)
#if !defined(BOOST_NO_CV_SPECIALIZATIONS)
AUX_REFERENCE_WRAPPER_METAFUNCTIONS_DEF(reference_wrapper<T> const)
AUX_REFERENCE_WRAPPER_METAFUNCTIONS_DEF(reference_wrapper<T> volatile)
AUX_REFERENCE_WRAPPER_METAFUNCTIONS_DEF(reference_wrapper<T> const volatile)
#endif
# undef AUX_REFERENCE_WRAPPER_METAFUNCTIONS_DEF
# 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
template<class T> inline T* get_pointer( reference_wrapper<T> const & r )
{
return r.get_pointer();
}
} // namespace boost
#endif // #ifndef BOOST_REF_HPP_INCLUDED