boost/fusion/container/vector/vector.hpp
/*=============================================================================
Copyright (c) 2014-2015 Kohei Takahashi
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 FUSION_VECTOR_11052014_1625
#define FUSION_VECTOR_11052014_1625
#include <boost/config.hpp>
#include <boost/fusion/support/config.hpp>
#include <boost/fusion/container/vector/detail/config.hpp>
#include <boost/fusion/container/vector/vector_fwd.hpp>
///////////////////////////////////////////////////////////////////////////////
// Without variadics, we will use the PP version
///////////////////////////////////////////////////////////////////////////////
#if !defined(BOOST_FUSION_HAS_VARIADIC_VECTOR)
# include <boost/fusion/container/vector/detail/cpp03/vector.hpp>
#else
///////////////////////////////////////////////////////////////////////////////
// C++11 interface
///////////////////////////////////////////////////////////////////////////////
#include <boost/fusion/support/sequence_base.hpp>
#include <boost/fusion/support/is_sequence.hpp>
#include <boost/fusion/support/detail/and.hpp>
#include <boost/fusion/support/detail/index_sequence.hpp>
#include <boost/fusion/container/vector/detail/at_impl.hpp>
#include <boost/fusion/container/vector/detail/value_at_impl.hpp>
#include <boost/fusion/container/vector/detail/begin_impl.hpp>
#include <boost/fusion/container/vector/detail/end_impl.hpp>
#include <boost/fusion/sequence/intrinsic/begin.hpp>
#include <boost/fusion/sequence/intrinsic/size.hpp>
#include <boost/fusion/iterator/advance.hpp>
#include <boost/fusion/iterator/deref.hpp>
#include <boost/core/enable_if.hpp>
#include <boost/mpl/int.hpp>
#include <boost/type_traits/integral_constant.hpp>
#include <boost/type_traits/is_base_of.hpp>
#include <boost/type_traits/is_convertible.hpp>
#include <boost/type_traits/remove_reference.hpp>
#include <cstddef>
#include <utility>
namespace boost { namespace fusion
{
struct vector_tag;
struct random_access_traversal_tag;
namespace vector_detail
{
struct each_elem {};
template <
typename This, typename T, typename T_, std::size_t Size, bool IsSeq
>
struct can_convert_impl : false_type {};
template <typename This, typename T, typename Sequence, std::size_t Size>
struct can_convert_impl<This, T, Sequence, Size, true> : true_type {};
template <typename This, typename Sequence, typename T>
struct can_convert_impl<This, Sequence, T, 1, true>
: integral_constant<
bool
, !is_convertible<
Sequence
, typename fusion::extension::value_at_impl<vector_tag>::
template apply< This, mpl::int_<0> >::type
>::value
>
{};
template <typename This, typename T, typename T_, std::size_t Size>
struct can_convert
: can_convert_impl<
This, T, T_, Size, traits::is_sequence<T_>::value
>
{};
template <typename T, bool IsSeq, std::size_t Size>
struct is_longer_sequence_impl : false_type {};
template <typename Sequence, std::size_t Size>
struct is_longer_sequence_impl<Sequence, true, Size>
: integral_constant<
bool, (fusion::result_of::size<Sequence>::value >= Size)
>
{};
template<typename T, std::size_t Size>
struct is_longer_sequence
: is_longer_sequence_impl<T, traits::is_sequence<T>::value, Size>
{};
// forward_at_c allows to access Nth element even if ForwardSequence
// since fusion::at_c requires RandomAccessSequence.
namespace result_of
{
template <typename Sequence, int N>
struct forward_at_c
: fusion::result_of::deref<
typename fusion::result_of::advance_c<
typename fusion::result_of::begin<
typename remove_reference<Sequence>::type
>::type
, N
>::type
>
{};
}
template <int N, typename Sequence>
BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
inline typename result_of::forward_at_c<Sequence, N>::type
forward_at_c(Sequence&& seq)
{
typedef typename
result_of::forward_at_c<Sequence, N>::type
result;
return std::forward<result>(*advance_c<N>(begin(seq)));
}
// Object proxy since preserve object order
template <std::size_t, typename T>
struct store
{
BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
store()
: elem() // value-initialized explicitly
{}
BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
store(store const& rhs)
: elem(rhs.elem)
{}
BOOST_CXX14_CONSTEXPR BOOST_FUSION_GPU_ENABLED
store&
operator=(store const& rhs)
{
elem = rhs.elem;
return *this;
}
BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
store(store&& rhs)
: elem(static_cast<T&&>(rhs.elem))
{}
BOOST_CXX14_CONSTEXPR BOOST_FUSION_GPU_ENABLED
store&
operator=(store&& rhs)
{
elem = static_cast<T&&>(rhs.elem);
return *this;
}
template <
typename U
, typename = typename boost::disable_if<
is_base_of<store, typename remove_reference<U>::type>
>::type
>
BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
store(U&& rhs)
: elem(std::forward<U>(rhs))
{}
using elem_type = T;
T elem;
};
// placed outside of vector_data due to GCC < 6 bug
template <std::size_t J, typename U>
static inline BOOST_FUSION_GPU_ENABLED
store<J, U> store_at_impl(store<J, U>*);
template <typename I, typename ...T>
struct vector_data;
template <std::size_t ...I, typename ...T>
struct vector_data<detail::index_sequence<I...>, T...>
: store<I, T>...
, sequence_base<vector_data<detail::index_sequence<I...>, T...> >
{
typedef vector_tag fusion_tag;
typedef fusion_sequence_tag tag; // this gets picked up by MPL
typedef mpl::false_ is_view;
typedef random_access_traversal_tag category;
typedef mpl::int_<sizeof...(T)> size;
typedef vector<T...> type_sequence;
BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
BOOST_DEFAULTED_FUNCTION(vector_data(), {})
template <
typename Sequence
, typename Sequence_ = typename remove_reference<Sequence>::type
, typename = typename boost::enable_if<
can_convert<vector_data, Sequence, Sequence_, sizeof...(I)>
>::type
>
BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
explicit
vector_data(each_elem, Sequence&& rhs)
: store<I, T>(forward_at_c<I>(std::forward<Sequence>(rhs)))...
{}
template <typename ...U>
BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
explicit
vector_data(each_elem, U&&... var)
: store<I, T>(std::forward<U>(var))...
{}
template <typename Sequence>
BOOST_CXX14_CONSTEXPR BOOST_FUSION_GPU_ENABLED
void
assign_sequence(Sequence&& seq)
{
#ifndef BOOST_NO_CXX17_FOLD_EXPRESSIONS
(void(store<I, T>::elem = vector_detail::forward_at_c<I>(static_cast<Sequence&&>(seq))), ...);
#else
int nofold[] = { (void(store<I, T>::elem = vector_detail::forward_at_c<I>(static_cast<Sequence&&>(seq))), 0)..., 0 };
(void)nofold;
#endif
}
private:
template <std::size_t J>
using store_at = decltype(store_at_impl<J>(static_cast<vector_data*>(nullptr)));
public:
template <typename J>
BOOST_CXX14_CONSTEXPR BOOST_FUSION_GPU_ENABLED
typename store_at<J::value>::elem_type& at_impl(J)
{
return store_at<J::value>::elem;
}
template <typename J>
BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
typename store_at<J::value>::elem_type const& at_impl(J) const
{
return store_at<J::value>::elem;
}
};
} // namespace boost::fusion::vector_detail
template <typename... T>
struct vector
: vector_detail::vector_data<
typename detail::make_index_sequence<sizeof...(T)>::type
, T...
>
{
typedef vector_detail::vector_data<
typename detail::make_index_sequence<sizeof...(T)>::type
, T...
> base;
BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
BOOST_DEFAULTED_FUNCTION(vector(), {})
template <
typename... U
, typename = typename boost::enable_if_c<(
sizeof...(U) >= 1 &&
fusion::detail::and_<is_convertible<U, T>...>::value &&
!fusion::detail::and_<
is_base_of<vector, typename remove_reference<U>::type>...
>::value
)>::type
>
// XXX: constexpr become error due to pull-request #79, booooo!!
// In the (near) future release, should be fixed.
/* BOOST_CONSTEXPR */ BOOST_FUSION_GPU_ENABLED
explicit vector(U&&... u)
: base(vector_detail::each_elem(), std::forward<U>(u)...)
{}
template <
typename Sequence
, typename = typename boost::enable_if_c<
vector_detail::is_longer_sequence<
typename remove_reference<Sequence>::type, sizeof...(T)
>::value
>::type
>
BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
vector(Sequence&& seq)
: base(vector_detail::each_elem(), std::forward<Sequence>(seq))
{}
template <typename Sequence>
BOOST_CXX14_CONSTEXPR BOOST_FUSION_GPU_ENABLED
vector&
operator=(Sequence&& rhs)
{
base::assign_sequence(std::forward<Sequence>(rhs));
return *this;
}
};
}}
#endif
#endif
