ecency-mobile/ios/Pods/boost-for-react-native/boost/variant/detail/initializer.hpp

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//-----------------------------------------------------------------------------
// boost variant/detail/initializer.hpp header file
// See http://www.boost.org for updates, documentation, and revision history.
//-----------------------------------------------------------------------------
//
// Copyright (c) 2002-2003
// Eric Friedman, Itay Maman
//
// 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)
#ifndef BOOST_VARIANT_DETAIL_INITIALIZER_HPP
#define BOOST_VARIANT_DETAIL_INITIALIZER_HPP
#include <new> // for placement new
#include <boost/config.hpp>
#include <boost/call_traits.hpp>
#include <boost/detail/reference_content.hpp>
#include <boost/variant/recursive_wrapper_fwd.hpp>
#include <boost/variant/detail/move.hpp>
#if !defined(BOOST_NO_USING_DECLARATION_OVERLOADS_FROM_TYPENAME_BASE)
# include <boost/mpl/aux_/value_wknd.hpp>
# include <boost/mpl/int.hpp>
# include <boost/mpl/iter_fold.hpp>
# include <boost/mpl/next.hpp>
# include <boost/mpl/deref.hpp>
# include <boost/mpl/pair.hpp>
# include <boost/mpl/protect.hpp>
#else
# include <boost/variant/variant_fwd.hpp>
# include <boost/preprocessor/cat.hpp>
# include <boost/preprocessor/enum.hpp>
# include <boost/preprocessor/repeat.hpp>
#endif
namespace boost {
namespace detail { namespace variant {
///////////////////////////////////////////////////////////////////////////////
// (detail) support to simulate standard overload resolution rules
//
// The below initializers allows variant to follow standard overload
// resolution rules over the specified set of bounded types.
//
// On compilers where using declarations in class templates can correctly
// avoid name hiding, use an optimal solution based on the variant's typelist.
//
// Otherwise, use a preprocessor workaround based on knowledge of the fixed
// size of the variant's psuedo-variadic template parameter list.
//
#if !defined(BOOST_NO_USING_DECLARATION_OVERLOADS_FROM_TYPENAME_BASE)
// (detail) quoted metafunction make_initializer_node
//
// Exposes a pair whose first type is a node in the initializer hierarchy.
//
struct make_initializer_node
{
template <typename BaseIndexPair, typename Iterator>
struct apply
{
private: // helpers, for metafunction result (below)
typedef typename BaseIndexPair::first
base;
typedef typename BaseIndexPair::second
index;
class initializer_node
: public base
{
private: // helpers, for static functions (below)
typedef typename mpl::deref<Iterator>::type
recursive_enabled_T;
typedef typename unwrap_recursive<recursive_enabled_T>::type
public_T;
#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
typedef boost::is_reference<public_T>
is_reference_content_t;
typedef typename boost::mpl::if_<is_reference_content_t, public_T, const public_T& >::type
param_T;
template <class T> struct disable_overload{};
typedef typename boost::mpl::if_<is_reference_content_t, disable_overload<public_T>, public_T&& >::type
param2_T;
#else
typedef typename call_traits<public_T>::param_type
param_T;
#endif
public: // static functions
using base::initialize;
static int initialize(void* dest, param_T operand)
{
typedef typename boost::detail::make_reference_content<
recursive_enabled_T
>::type internal_T;
new(dest) internal_T(operand);
return BOOST_MPL_AUX_VALUE_WKND(index)::value; // which
}
#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
static int initialize(void* dest, param2_T operand)
{
// This assert must newer trigger, because all the reference contents are
// handled by the initilize(void* dest, param_T operand) function above
BOOST_ASSERT(!is_reference_content_t::value);
typedef typename boost::mpl::if_<is_reference_content_t, param2_T, recursive_enabled_T>::type value_T;
new(dest) value_T( boost::detail::variant::move(operand) );
return BOOST_MPL_AUX_VALUE_WKND(index)::value; // which
}
#endif
};
friend class initializer_node;
public: // metafunction result
typedef mpl::pair<
initializer_node
, typename mpl::next< index >::type
> type;
};
};
// (detail) class initializer_root
//
// Every level of the initializer hierarchy must expose the name
// "initialize," so initializer_root provides a dummy function:
//
class initializer_root
{
public: // static functions
static void initialize();
};
#else // defined(BOOST_NO_USING_DECLARATION_OVERLOADS_FROM_TYPENAME_BASE)
// Obsolete. Remove.
#define BOOST_VARIANT_AUX_PP_INITIALIZER_TEMPLATE_PARAMS \
BOOST_VARIANT_ENUM_PARAMS(typename recursive_enabled_T) \
/**/
// Obsolete. Remove.
#define BOOST_VARIANT_AUX_PP_INITIALIZER_DEFINE_PARAM_T(N) \
typedef typename unwrap_recursive< \
BOOST_PP_CAT(recursive_enabled_T,N) \
>::type BOOST_PP_CAT(public_T,N); \
typedef typename call_traits< \
BOOST_PP_CAT(public_T,N) \
>::param_type BOOST_PP_CAT(param_T,N); \
/**/
template < BOOST_VARIANT_ENUM_PARAMS(typename recursive_enabled_T) >
struct preprocessor_list_initializer
{
public: // static functions
#define BOOST_VARIANT_AUX_PP_INITIALIZE_FUNCTION(z,N,_) \
typedef typename unwrap_recursive< \
BOOST_PP_CAT(recursive_enabled_T,N) \
>::type BOOST_PP_CAT(public_T,N); \
typedef typename call_traits< \
BOOST_PP_CAT(public_T,N) \
>::param_type BOOST_PP_CAT(param_T,N); \
static int initialize( \
void* dest \
, BOOST_PP_CAT(param_T,N) operand \
) \
{ \
typedef typename boost::detail::make_reference_content< \
BOOST_PP_CAT(recursive_enabled_T,N) \
>::type internal_T; \
\
new(dest) internal_T(operand); \
return (N); /*which*/ \
} \
/**/
BOOST_PP_REPEAT(
BOOST_VARIANT_LIMIT_TYPES
, BOOST_VARIANT_AUX_PP_INITIALIZE_FUNCTION
, _
)
#undef BOOST_VARIANT_AUX_PP_INITIALIZE_FUNCTION
};
#endif // BOOST_NO_USING_DECLARATION_OVERLOADS_FROM_TYPENAME_BASE workaround
}} // namespace detail::variant
} // namespace boost
///////////////////////////////////////////////////////////////////////////////
// macro BOOST_VARIANT_AUX_INITIALIZER_T
//
// Given both the variant's typelist and a basename for forming the list of
// bounded types (i.e., T becomes T1, T2, etc.), exposes the initializer
// most appropriate to the current compiler.
//
#if !defined(BOOST_NO_USING_DECLARATION_OVERLOADS_FROM_TYPENAME_BASE)
#define BOOST_VARIANT_AUX_INITIALIZER_T( mpl_seq, typename_base ) \
::boost::mpl::iter_fold< \
mpl_seq \
, ::boost::mpl::pair< \
::boost::detail::variant::initializer_root \
, ::boost::mpl::int_<0> \
> \
, ::boost::mpl::protect< \
::boost::detail::variant::make_initializer_node \
> \
>::type::first \
/**/
#else // defined(BOOST_NO_USING_DECLARATION_OVERLOADS_FROM_TYPENAME_BASE)
// Obsolete. Remove.
#define BOOST_VARIANT_AUX_PP_INITIALIZER_TEMPLATE_ARGS(typename_base) \
BOOST_VARIANT_ENUM_PARAMS(typename_base) \
/**/
#define BOOST_VARIANT_AUX_INITIALIZER_T( mpl_seq, typename_base ) \
::boost::detail::variant::preprocessor_list_initializer< \
BOOST_VARIANT_ENUM_PARAMS(typename_base) \
> \
/**/
#endif // BOOST_NO_USING_DECLARATION_OVERLOADS_FROM_TYPENAME_BASE workaround
#endif // BOOST_VARIANT_DETAIL_INITIALIZER_HPP