Anurag Bhat 86b4fc623c
Merge numpy to pocketpy (#303)
* Merge numpy to pocketpy

* Add CI

* Fix CI
2024-09-02 16:22:41 +08:00

1135 lines
32 KiB
C++

/***************************************************************************
* Copyright (c) Johan Mabille, Sylvain Corlay and Wolf Vollprecht *
* Copyright (c) QuantStack *
* *
* Distributed under the terms of the BSD 3-Clause License. *
* *
* The full license is in the file LICENSE, distributed with this software. *
****************************************************************************/
#ifndef XTENSOR_UTILS_HPP
#define XTENSOR_UTILS_HPP
#include <algorithm>
#include <array>
#include <cmath>
#include <complex>
#include <cstddef>
#include <initializer_list>
#include <iostream>
#include <memory>
#include <tuple>
#include <type_traits>
#include <utility>
#include <vector>
#include <xtl/xfunctional.hpp>
#include <xtl/xmeta_utils.hpp>
#include <xtl/xsequence.hpp>
#include <xtl/xtype_traits.hpp>
#include "xtensor_config.hpp"
#if (_MSC_VER >= 1910)
#define NOEXCEPT(T)
#else
#define NOEXCEPT(T) noexcept(T)
#endif
namespace xt
{
/****************
* declarations *
****************/
template <class T>
struct remove_class;
/*template <class F, class... T>
void for_each(F&& f, std::tuple<T...>& t) noexcept(implementation_dependent);*/
/*template <class F, class R, class... T>
R accumulate(F&& f, R init, const std::tuple<T...>& t) noexcept(implementation_dependent);*/
template <std::size_t I, class... Args>
constexpr decltype(auto) argument(Args&&... args) noexcept;
template <class R, class F, class... S>
R apply(std::size_t index, F&& func, const std::tuple<S...>& s) NOEXCEPT(noexcept(func(std::get<0>(s))));
template <class T, class S>
void nested_copy(T&& iter, const S& s);
template <class T, class S>
void nested_copy(T&& iter, std::initializer_list<S> s);
template <class C>
bool resize_container(C& c, typename C::size_type size);
template <class T, std::size_t N>
bool resize_container(std::array<T, N>& a, typename std::array<T, N>::size_type size);
template <std::size_t... I>
class fixed_shape;
template <std::size_t... I>
bool resize_container(fixed_shape<I...>& a, std::size_t size);
template <class X, class C>
struct rebind_container;
template <class X, class C>
using rebind_container_t = typename rebind_container<X, C>::type;
std::size_t normalize_axis(std::size_t dim, std::ptrdiff_t axis);
// gcc 4.9 is affected by C++14 defect CGW 1558
// see http://open-std.org/JTC1/SC22/WG21/docs/cwg_defects.html#1558
template <class... T>
struct make_void
{
using type = void;
};
template <class... T>
using void_t = typename make_void<T...>::type;
// This is used for non existent types (e.g. storage for some expressions
// like generators)
struct invalid_type
{
};
template <class... T>
struct make_invalid_type
{
using type = invalid_type;
};
template <class T, class R>
using disable_integral_t = std::enable_if_t<!xtl::is_integral<T>::value, R>;
/********************************
* meta identity implementation *
********************************/
template <class T>
struct meta_identity
{
using type = T;
};
/***************************************
* is_specialization_of implementation *
***************************************/
template <template <class...> class TT, class T>
struct is_specialization_of : std::false_type
{
};
template <template <class...> class TT, class... Ts>
struct is_specialization_of<TT, TT<Ts...>> : std::true_type
{
};
/*******************************
* remove_class implementation *
*******************************/
template <class T>
struct remove_class
{
};
template <class C, class R, class... Args>
struct remove_class<R (C::*)(Args...)>
{
typedef R type(Args...);
};
template <class C, class R, class... Args>
struct remove_class<R (C::*)(Args...) const>
{
typedef R type(Args...);
};
template <class T>
using remove_class_t = typename remove_class<T>::type;
/***************************
* for_each implementation *
***************************/
namespace detail
{
template <std::size_t I, class F, class... T>
inline typename std::enable_if<I == sizeof...(T), void>::type
for_each_impl(F&& /*f*/, std::tuple<T...>& /*t*/) noexcept
{
}
template <std::size_t I, class F, class... T>
inline typename std::enable_if < I<sizeof...(T), void>::type
for_each_impl(F&& f, std::tuple<T...>& t) noexcept(noexcept(f(std::get<I>(t))))
{
f(std::get<I>(t));
for_each_impl<I + 1, F, T...>(std::forward<F>(f), t);
}
}
template <class F, class... T>
inline void for_each(F&& f, std::tuple<T...>& t) noexcept(
noexcept(detail::for_each_impl<0, F, T...>(std::forward<F>(f), t))
)
{
detail::for_each_impl<0, F, T...>(std::forward<F>(f), t);
}
namespace detail
{
template <std::size_t I, class F, class... T>
inline typename std::enable_if<I == sizeof...(T), void>::type
for_each_impl(F&& /*f*/, const std::tuple<T...>& /*t*/) noexcept
{
}
template <std::size_t I, class F, class... T>
inline typename std::enable_if < I<sizeof...(T), void>::type
for_each_impl(F&& f, const std::tuple<T...>& t) noexcept(noexcept(f(std::get<I>(t))))
{
f(std::get<I>(t));
for_each_impl<I + 1, F, T...>(std::forward<F>(f), t);
}
}
template <class F, class... T>
inline void for_each(F&& f, const std::tuple<T...>& t) noexcept(
noexcept(detail::for_each_impl<0, F, T...>(std::forward<F>(f), t))
)
{
detail::for_each_impl<0, F, T...>(std::forward<F>(f), t);
}
/*****************************
* accumulate implementation *
*****************************/
/// @cond DOXYGEN_INCLUDE_NOEXCEPT
namespace detail
{
template <std::size_t I, class F, class R, class... T>
inline std::enable_if_t<I == sizeof...(T), R>
accumulate_impl(F&& /*f*/, R init, const std::tuple<T...>& /*t*/) noexcept
{
return init;
}
template <std::size_t I, class F, class R, class... T>
inline std::enable_if_t < I<sizeof...(T), R>
accumulate_impl(F&& f, R init, const std::tuple<T...>& t) noexcept(noexcept(f(init, std::get<I>(t))))
{
R res = f(init, std::get<I>(t));
return accumulate_impl<I + 1, F, R, T...>(std::forward<F>(f), res, t);
}
}
template <class F, class R, class... T>
inline R accumulate(F&& f, R init, const std::tuple<T...>& t) noexcept(
noexcept(detail::accumulate_impl<0, F, R, T...>(std::forward<F>(f), init, t))
)
{
return detail::accumulate_impl<0, F, R, T...>(std::forward<F>(f), init, t);
}
/// @endcond
/***************************
* argument implementation *
***************************/
namespace detail
{
template <std::size_t I>
struct getter
{
template <class Arg, class... Args>
static constexpr decltype(auto) get(Arg&& /*arg*/, Args&&... args) noexcept
{
return getter<I - 1>::get(std::forward<Args>(args)...);
}
};
template <>
struct getter<0>
{
template <class Arg, class... Args>
static constexpr Arg&& get(Arg&& arg, Args&&... /*args*/) noexcept
{
return std::forward<Arg>(arg);
}
};
}
template <std::size_t I, class... Args>
constexpr decltype(auto) argument(Args&&... args) noexcept
{
static_assert(I < sizeof...(Args), "I should be lesser than sizeof...(Args)");
return detail::getter<I>::get(std::forward<Args>(args)...);
}
/************************
* apply implementation *
************************/
namespace detail
{
template <class R, class F, std::size_t I, class... S>
R apply_one(F&& func, const std::tuple<S...>& s) NOEXCEPT(noexcept(func(std::get<I>(s))))
{
return static_cast<R>(func(std::get<I>(s)));
}
template <class R, class F, std::size_t... I, class... S>
R apply(std::size_t index, F&& func, std::index_sequence<I...> /*seq*/, const std::tuple<S...>& s)
NOEXCEPT(noexcept(func(std::get<0>(s))))
{
using FT = std::add_pointer_t<R(F&&, const std::tuple<S...>&)>;
static const std::array<FT, sizeof...(I)> ar = {{&apply_one<R, F, I, S...>...}};
return ar[index](std::forward<F>(func), s);
}
}
template <class R, class F, class... S>
inline R apply(std::size_t index, F&& func, const std::tuple<S...>& s)
NOEXCEPT(noexcept(func(std::get<0>(s))))
{
return detail::apply<R>(index, std::forward<F>(func), std::make_index_sequence<sizeof...(S)>(), s);
}
/***************************
* nested_initializer_list *
***************************/
template <class T, std::size_t I>
struct nested_initializer_list
{
using type = std::initializer_list<typename nested_initializer_list<T, I - 1>::type>;
};
template <class T>
struct nested_initializer_list<T, 0>
{
using type = T;
};
template <class T, std::size_t I>
using nested_initializer_list_t = typename nested_initializer_list<T, I>::type;
/******************************
* nested_copy implementation *
******************************/
template <class T, class S>
inline void nested_copy(T&& iter, const S& s)
{
*iter++ = s;
}
template <class T, class S>
inline void nested_copy(T&& iter, std::initializer_list<S> s)
{
for (auto it = s.begin(); it != s.end(); ++it)
{
nested_copy(std::forward<T>(iter), *it);
}
}
/***********************************
* resize_container implementation *
***********************************/
template <class C>
inline bool resize_container(C& c, typename C::size_type size)
{
c.resize(size);
return true;
}
template <class T, std::size_t N>
inline bool resize_container(std::array<T, N>& /*a*/, typename std::array<T, N>::size_type size)
{
return size == N;
}
template <std::size_t... I>
inline bool resize_container(xt::fixed_shape<I...>&, std::size_t size)
{
return sizeof...(I) == size;
}
/*********************************
* normalize_axis implementation *
*********************************/
// scalar normalize axis
inline std::size_t normalize_axis(std::size_t dim, std::ptrdiff_t axis)
{
return axis < 0 ? static_cast<std::size_t>(static_cast<std::ptrdiff_t>(dim) + axis)
: static_cast<std::size_t>(axis);
}
template <class E, class C>
inline std::enable_if_t<
!xtl::is_integral<std::decay_t<C>>::value && xtl::is_signed<typename std::decay_t<C>::value_type>::value,
rebind_container_t<std::size_t, std::decay_t<C>>>
normalize_axis(E& expr, C&& axes)
{
rebind_container_t<std::size_t, std::decay_t<C>> res;
resize_container(res, axes.size());
for (std::size_t i = 0; i < axes.size(); ++i)
{
res[i] = normalize_axis(expr.dimension(), axes[i]);
}
XTENSOR_ASSERT(std::all_of(
res.begin(),
res.end(),
[&expr](auto ax_el)
{
return ax_el < expr.dimension();
}
));
return res;
}
template <class C, class E>
inline std::enable_if_t<
!xtl::is_integral<std::decay_t<C>>::value && std::is_unsigned<typename std::decay_t<C>::value_type>::value,
C&&>
normalize_axis(E& expr, C&& axes)
{
static_cast<void>(expr);
XTENSOR_ASSERT(std::all_of(
axes.begin(),
axes.end(),
[&expr](auto ax_el)
{
return ax_el < expr.dimension();
}
));
return std::forward<C>(axes);
}
template <class R, class E, class C>
inline auto forward_normalize(E& expr, C&& axes)
-> std::enable_if_t<xtl::is_signed<std::decay_t<decltype(*std::begin(axes))>>::value, R>
{
R res;
xt::resize_container(res, xtl::sequence_size(axes));
auto dim = expr.dimension();
std::transform(
std::begin(axes),
std::end(axes),
std::begin(res),
[&dim](auto ax_el)
{
return normalize_axis(dim, ax_el);
}
);
XTENSOR_ASSERT(std::all_of(
res.begin(),
res.end(),
[&expr](auto ax_el)
{
return ax_el < expr.dimension();
}
));
return res;
}
template <class R, class E, class C>
inline auto forward_normalize(E& expr, C&& axes) -> std::enable_if_t<
!xtl::is_signed<std::decay_t<decltype(*std::begin(axes))>>::value && !std::is_same<R, std::decay_t<C>>::value,
R>
{
static_cast<void>(expr);
R res;
xt::resize_container(res, xtl::sequence_size(axes));
std::copy(std::begin(axes), std::end(axes), std::begin(res));
XTENSOR_ASSERT(std::all_of(
res.begin(),
res.end(),
[&expr](auto ax_el)
{
return ax_el < expr.dimension();
}
));
return res;
}
template <class R, class E, class C>
inline auto forward_normalize(E& expr, C&& axes) -> std::enable_if_t<
!xtl::is_signed<std::decay_t<decltype(*std::begin(axes))>>::value && std::is_same<R, std::decay_t<C>>::value,
R&&>
{
static_cast<void>(expr);
XTENSOR_ASSERT(std::all_of(
std::begin(axes),
std::end(axes),
[&expr](auto ax_el)
{
return ax_el < expr.dimension();
}
));
return std::move(axes);
}
/******************
* get_value_type *
******************/
template <class T, class = void_t<>>
struct get_value_type
{
using type = T;
};
template <class T>
struct get_value_type<T, void_t<typename T::value_type>>
{
using type = typename T::value_type;
};
template <class T>
using get_value_type_t = typename get_value_type<T>::type;
/**********************
* get implementation *
**********************/
// When subclassing from std::tuple not all compilers are able to correctly instantiate get
// See here: https://stackoverflow.com/a/37188019/2528668
template <std::size_t I, template <typename... Args> class T, typename... Args>
decltype(auto) get(T<Args...>&& v)
{
return std::get<I>(static_cast<std::tuple<Args...>&&>(v));
}
template <std::size_t I, template <typename... Args> class T, typename... Args>
decltype(auto) get(T<Args...>& v)
{
return std::get<I>(static_cast<std::tuple<Args...>&>(v));
}
template <std::size_t I, template <typename... Args> class T, typename... Args>
decltype(auto) get(const T<Args...>& v)
{
return std::get<I>(static_cast<const std::tuple<Args...>&>(v));
}
/***************************
* apply_cv implementation *
***************************/
namespace detail
{
template <
class T,
class U,
bool = std::is_const<std::remove_reference_t<T>>::value,
bool = std::is_volatile<std::remove_reference_t<T>>::value>
struct apply_cv_impl
{
using type = U;
};
template <class T, class U>
struct apply_cv_impl<T, U, true, false>
{
using type = const U;
};
template <class T, class U>
struct apply_cv_impl<T, U, false, true>
{
using type = volatile U;
};
template <class T, class U>
struct apply_cv_impl<T, U, true, true>
{
using type = const volatile U;
};
template <class T, class U>
struct apply_cv_impl<T&, U, false, false>
{
using type = U&;
};
template <class T, class U>
struct apply_cv_impl<T&, U, true, false>
{
using type = const U&;
};
template <class T, class U>
struct apply_cv_impl<T&, U, false, true>
{
using type = volatile U&;
};
template <class T, class U>
struct apply_cv_impl<T&, U, true, true>
{
using type = const volatile U&;
};
}
template <class T, class U>
struct apply_cv
{
using type = typename detail::apply_cv_impl<T, U>::type;
};
template <class T, class U>
using apply_cv_t = typename apply_cv<T, U>::type;
/**************************
* to_array implementation *
***************************/
namespace detail
{
template <class T, std::size_t N, std::size_t... I>
constexpr std::array<std::remove_cv_t<T>, N> to_array_impl(T (&a)[N], std::index_sequence<I...>)
{
return {{a[I]...}};
}
}
template <class T, std::size_t N>
constexpr std::array<std::remove_cv_t<T>, N> to_array(T (&a)[N])
{
return detail::to_array_impl(a, std::make_index_sequence<N>{});
}
/********************************
* sequence_size implementation *
********************************/
// equivalent to std::size(c) in c++17
template <class C>
constexpr auto sequence_size(const C& c) -> decltype(c.size())
{
return c.size();
}
// equivalent to std::size(a) in c++17
template <class T, std::size_t N>
constexpr std::size_t sequence_size(const T (&)[N])
{
return N;
}
/***********************************
* has_storage_type implementation *
***********************************/
template <class T, class = void>
struct has_storage_type : std::false_type
{
};
template <class T>
struct xcontainer_inner_types;
template <class T>
struct has_storage_type<T, void_t<typename xcontainer_inner_types<T>::storage_type>>
: xtl::negation<
std::is_same<typename std::remove_cv<typename xcontainer_inner_types<T>::storage_type>::type, invalid_type>>
{
};
/*************************************
* has_data_interface implementation *
*************************************/
template <class E, class = void>
struct has_data_interface : std::false_type
{
};
template <class E>
struct has_data_interface<E, void_t<decltype(std::declval<E>().data())>> : std::true_type
{
};
template <class E, class = void>
struct has_strides : std::false_type
{
};
template <class E>
struct has_strides<E, void_t<decltype(std::declval<E>().strides())>> : std::true_type
{
};
template <class E, class = void>
struct has_iterator_interface : std::false_type
{
};
template <class E>
struct has_iterator_interface<E, void_t<decltype(std::declval<E>().begin())>> : std::true_type
{
};
/******************************
* is_iterator implementation *
******************************/
template <class E, class = void>
struct is_iterator : std::false_type
{
};
template <class E>
struct is_iterator<
E,
void_t<
decltype(*std::declval<const E>(), std::declval<const E>() == std::declval<const E>(), std::declval<const E>() != std::declval<const E>(), ++(*std::declval<E*>()), (*std::declval<E*>())++, std::true_type())>>
: std::true_type
{
};
/********************************************
* xtrivial_default_construct implemenation *
********************************************/
#if defined(_GLIBCXX_RELEASE) && _GLIBCXX_RELEASE >= 7
// has_trivial_default_constructor has not been available since libstdc++-7.
#define XTENSOR_GLIBCXX_USE_CXX11_ABI 1
#else
#if defined(_GLIBCXX_USE_CXX11_ABI)
#if _GLIBCXX_USE_CXX11_ABI || (defined(_GLIBCXX_USE_DUAL_ABI) && !_GLIBCXX_USE_DUAL_ABI)
#define XTENSOR_GLIBCXX_USE_CXX11_ABI 1
#endif
#endif
#endif
#if !defined(__GNUG__) || defined(_LIBCPP_VERSION) || defined(XTENSOR_GLIBCXX_USE_CXX11_ABI)
template <class T>
using xtrivially_default_constructible = std::is_trivially_default_constructible<T>;
#else
template <class T>
using xtrivially_default_constructible = std::has_trivial_default_constructor<T>;
#endif
#undef XTENSOR_GLIBCXX_USE_CXX11_ABI
/*************************
* conditional type cast *
*************************/
template <bool condition, class T>
struct conditional_cast_functor;
template <class T>
struct conditional_cast_functor<false, T> : public xtl::identity
{
};
template <class T>
struct conditional_cast_functor<true, T>
{
template <class U>
inline auto operator()(U&& u) const
{
return static_cast<T>(std::forward<U>(u));
}
};
/**
* @brief Perform a type cast when a condition is true.
* If <tt>condition</tt> is true, return <tt>static_cast<T>(u)</tt>,
* otherwise return <tt>u</tt> unchanged. This is useful when an unconditional
* static_cast would force undesired type conversions in some situations where
* an error or warning would be desired. The condition determines when the
* explicit cast is ok.
*/
template <bool condition, class T, class U>
inline auto conditional_cast(U&& u)
{
return conditional_cast_functor<condition, T>()(std::forward<U>(u));
}
/**********************
* tracking allocator *
**********************/
namespace alloc_tracking
{
inline bool& enabled()
{
static bool enabled;
return enabled;
}
inline void enable()
{
enabled() = true;
}
inline void disable()
{
enabled() = false;
}
enum policy
{
print,
assert
};
}
template <class T, class A, alloc_tracking::policy P>
struct tracking_allocator : private A
{
using base_type = A;
using value_type = typename A::value_type;
using reference = typename A::reference;
using const_reference = typename A::const_reference;
using pointer = typename A::pointer;
using const_pointer = typename A::const_pointer;
using size_type = typename A::size_type;
using difference_type = typename A::difference_type;
tracking_allocator() = default;
T* allocate(std::size_t n)
{
if (alloc_tracking::enabled())
{
if (P == alloc_tracking::print)
{
std::cout << "xtensor allocating: " << n << "" << std::endl;
}
else if (P == alloc_tracking::assert)
{
XTENSOR_THROW(
std::runtime_error,
"xtensor allocation of " + std::to_string(n) + " elements detected"
);
}
}
return base_type::allocate(n);
}
using base_type::construct;
using base_type::deallocate;
using base_type::destroy;
template <class U>
struct rebind
{
using traits = std::allocator_traits<A>;
using other = tracking_allocator<U, typename traits::template rebind_alloc<U>, P>;
};
};
template <class T, class AT, alloc_tracking::policy PT, class U, class AU, alloc_tracking::policy PU>
inline bool operator==(const tracking_allocator<T, AT, PT>&, const tracking_allocator<U, AU, PU>&)
{
return std::is_same<AT, AU>::value;
}
template <class T, class AT, alloc_tracking::policy PT, class U, class AU, alloc_tracking::policy PU>
inline bool operator!=(const tracking_allocator<T, AT, PT>& a, const tracking_allocator<U, AU, PU>& b)
{
return !(a == b);
}
/*****************
* has_assign_to *
*****************/
template <class E1, class E2, class = void>
struct has_assign_to : std::false_type
{
};
template <class E1, class E2>
struct has_assign_to<E1, E2, void_t<decltype(std::declval<const E2&>().assign_to(std::declval<E1&>()))>>
: std::true_type
{
};
/*************************************
* overlapping_memory_checker_traits *
*************************************/
template <class T, class Enable = void>
struct has_memory_address : std::false_type
{
};
template <class T>
struct has_memory_address<T, void_t<decltype(std::addressof(*std::declval<T>().begin()))>> : std::true_type
{
};
struct memory_range
{
// Checking pointer overlap is more correct in integer values,
// for more explanation check https://devblogs.microsoft.com/oldnewthing/20170927-00/?p=97095
const uintptr_t m_first = 0;
const uintptr_t m_last = 0;
explicit memory_range() = default;
template <class T>
explicit memory_range(T* first, T* last)
: m_first(reinterpret_cast<uintptr_t>(last < first ? last : first))
, m_last(reinterpret_cast<uintptr_t>(last < first ? first : last))
{
}
template <class T>
bool overlaps(T* first, T* last) const
{
if (first <= last)
{
return reinterpret_cast<uintptr_t>(first) <= m_last
&& reinterpret_cast<uintptr_t>(last) >= m_first;
}
else
{
return reinterpret_cast<uintptr_t>(last) <= m_last
&& reinterpret_cast<uintptr_t>(first) >= m_first;
}
}
};
template <class E, class Enable = void>
struct overlapping_memory_checker_traits
{
static bool check_overlap(const E&, const memory_range&)
{
return true;
}
};
template <class E>
struct overlapping_memory_checker_traits<E, std::enable_if_t<has_memory_address<E>::value>>
{
static bool check_overlap(const E& expr, const memory_range& dst_range)
{
if (expr.size() == 0)
{
return false;
}
else
{
return dst_range.overlaps(std::addressof(*expr.begin()), std::addressof(*expr.rbegin()));
}
}
};
struct overlapping_memory_checker_base
{
memory_range m_dst_range;
explicit overlapping_memory_checker_base() = default;
explicit overlapping_memory_checker_base(memory_range dst_memory_range)
: m_dst_range(std::move(dst_memory_range))
{
}
template <class E>
bool check_overlap(const E& expr) const
{
if (!m_dst_range.m_first || !m_dst_range.m_last)
{
return false;
}
else
{
return overlapping_memory_checker_traits<E>::check_overlap(expr, m_dst_range);
}
}
};
template <class Dst, class Enable = void>
struct overlapping_memory_checker : overlapping_memory_checker_base
{
explicit overlapping_memory_checker(const Dst&)
: overlapping_memory_checker_base()
{
}
};
template <class Dst>
struct overlapping_memory_checker<Dst, std::enable_if_t<has_memory_address<Dst>::value>>
: overlapping_memory_checker_base
{
explicit overlapping_memory_checker(const Dst& aDst)
: overlapping_memory_checker_base(
[&]()
{
if (aDst.size() == 0)
{
return memory_range();
}
else
{
return memory_range(std::addressof(*aDst.begin()), std::addressof(*aDst.rbegin()));
}
}()
)
{
}
};
template <class Dst>
auto make_overlapping_memory_checker(const Dst& a_dst)
{
return overlapping_memory_checker<Dst>(a_dst);
}
/********************
* rebind_container *
********************/
template <class X, template <class, class> class C, class T, class A>
struct rebind_container<X, C<T, A>>
{
using traits = std::allocator_traits<A>;
using allocator = typename traits::template rebind_alloc<X>;
using type = C<X, allocator>;
};
#if defined(__GNUC__) && __GNUC__ > 6 && !defined(__clang__) && __cplusplus >= 201703L
template <class X, class T, std::size_t N>
struct rebind_container<X, std::array<T, N>>
{
using type = std::array<X, N>;
};
#else
template <class X, template <class, std::size_t> class C, class T, std::size_t N>
struct rebind_container<X, C<T, N>>
{
using type = C<X, N>;
};
#endif
/********************
* get_strides_type *
********************/
template <class S>
struct get_strides_type
{
using type = typename rebind_container<std::ptrdiff_t, S>::type;
};
template <std::size_t... I>
struct get_strides_type<fixed_shape<I...>>
{
// TODO we could compute the strides statically here.
// But we'll need full constexpr support to have a
// homogenous ``compute_strides`` method
using type = std::array<std::ptrdiff_t, sizeof...(I)>;
};
template <class CP, class O, class A>
class xbuffer_adaptor;
template <class CP, class O, class A>
struct get_strides_type<xbuffer_adaptor<CP, O, A>>
{
// In bindings this mapping is called by reshape_view with an inner shape of type
// xbuffer_adaptor.
// Since we cannot create a buffer adaptor holding data, we map it to an std::vector.
using type = std::vector<
typename xbuffer_adaptor<CP, O, A>::value_type,
typename xbuffer_adaptor<CP, O, A>::allocator_type>;
};
template <class C>
using get_strides_t = typename get_strides_type<C>::type;
/*******************
* inner_reference *
*******************/
template <class ST>
struct inner_reference
{
using storage_type = std::decay_t<ST>;
using type = std::conditional_t<
std::is_const<std::remove_reference_t<ST>>::value,
typename storage_type::const_reference,
typename storage_type::reference>;
};
template <class ST>
using inner_reference_t = typename inner_reference<ST>::type;
/************
* get_rank *
************/
template <class E, typename = void>
struct get_rank
{
static constexpr std::size_t value = SIZE_MAX;
};
template <class E>
struct get_rank<E, decltype((void) E::rank, void())>
{
static constexpr std::size_t value = E::rank;
};
/******************
* has_fixed_rank *
******************/
template <class E>
struct has_fixed_rank
{
using type = std::integral_constant<bool, get_rank<std::decay_t<E>>::value != SIZE_MAX>;
};
template <class E>
using has_fixed_rank_t = typename has_fixed_rank<std::decay_t<E>>::type;
/************
* has_rank *
************/
template <class E, size_t N>
struct has_rank
{
using type = std::integral_constant<bool, get_rank<std::decay_t<E>>::value == N>;
};
template <class E, size_t N>
using has_rank_t = typename has_rank<std::decay_t<E>, N>::type;
}
#endif