| // -*- C++ -*- |
| //===----------------------------------------------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===---------------------------------------------------------------------===// |
| |
| #ifndef _LIBCPP_SPAN |
| #define _LIBCPP_SPAN |
| |
| /* |
| span synopsis |
| |
| namespace std { |
| |
| // constants |
| inline constexpr size_t dynamic_extent = numeric_limits<size_t>::max(); |
| |
| // [views.span], class template span |
| template <class ElementType, size_t Extent = dynamic_extent> |
| class span; |
| |
| template<class ElementType, size_t Extent> |
| inline constexpr bool ranges::enable_view<span<ElementType, Extent>> = true; |
| |
| template<class ElementType, size_t Extent> |
| inline constexpr bool ranges::enable_borrowed_range<span<ElementType, Extent>> = true; |
| |
| // [span.objectrep], views of object representation |
| template <class ElementType, size_t Extent> |
| span<const byte, ((Extent == dynamic_extent) ? dynamic_extent : |
| (sizeof(ElementType) * Extent))> as_bytes(span<ElementType, Extent> s) noexcept; |
| |
| template <class ElementType, size_t Extent> |
| span< byte, ((Extent == dynamic_extent) ? dynamic_extent : |
| (sizeof(ElementType) * Extent))> as_writable_bytes(span<ElementType, Extent> s) noexcept; |
| |
| |
| template <class ElementType, size_t Extent = dynamic_extent> |
| class span { |
| public: |
| // constants and types |
| using element_type = ElementType; |
| using value_type = remove_cv_t<ElementType>; |
| using size_type = size_t; |
| using difference_type = ptrdiff_t; |
| using pointer = element_type*; |
| using const_pointer = const element_type*; |
| using reference = element_type&; |
| using const_reference = const element_type&; |
| using iterator = implementation-defined; |
| using reverse_iterator = std::reverse_iterator<iterator>; |
| static constexpr size_type extent = Extent; |
| |
| // [span.cons], span constructors, copy, assignment, and destructor |
| constexpr span() noexcept; |
| template <class It> |
| constexpr explicit(Extent != dynamic_extent) span(It first, size_type count); |
| template <class It, class End> |
| constexpr explicit(Extent != dynamic_extent) span(It first, End last); |
| template <size_t N> |
| constexpr span(type_identity_t<element_type> (&arr)[N]) noexcept; |
| template <size_t N> |
| constexpr span(array<value_type, N>& arr) noexcept; |
| template <size_t N> |
| constexpr span(const array<value_type, N>& arr) noexcept; |
| template<class R> |
| constexpr explicit(Extent != dynamic_extent) span(R&& r); |
| constexpr span(const span& other) noexcept = default; |
| template <class OtherElementType, size_t OtherExtent> |
| constexpr explicit(Extent != dynamic_extent) span(const span<OtherElementType, OtherExtent>& s) noexcept; |
| ~span() noexcept = default; |
| constexpr span& operator=(const span& other) noexcept = default; |
| |
| // [span.sub], span subviews |
| template <size_t Count> |
| constexpr span<element_type, Count> first() const; |
| template <size_t Count> |
| constexpr span<element_type, Count> last() const; |
| template <size_t Offset, size_t Count = dynamic_extent> |
| constexpr span<element_type, see below> subspan() const; |
| |
| constexpr span<element_type, dynamic_extent> first(size_type count) const; |
| constexpr span<element_type, dynamic_extent> last(size_type count) const; |
| constexpr span<element_type, dynamic_extent> subspan(size_type offset, size_type count = dynamic_extent) const; |
| |
| // [span.obs], span observers |
| constexpr size_type size() const noexcept; |
| constexpr size_type size_bytes() const noexcept; |
| [[nodiscard]] constexpr bool empty() const noexcept; |
| |
| // [span.elem], span element access |
| constexpr reference operator[](size_type idx) const; |
| constexpr reference front() const; |
| constexpr reference back() const; |
| constexpr pointer data() const noexcept; |
| |
| // [span.iterators], span iterator support |
| constexpr iterator begin() const noexcept; |
| constexpr iterator end() const noexcept; |
| constexpr reverse_iterator rbegin() const noexcept; |
| constexpr reverse_iterator rend() const noexcept; |
| |
| private: |
| pointer data_; // exposition only |
| size_type size_; // exposition only |
| }; |
| |
| template<class It, class EndOrSize> |
| span(It, EndOrSize) -> span<remove_reference_t<iter_reference_t<_It>>>; |
| |
| template<class T, size_t N> |
| span(T (&)[N]) -> span<T, N>; |
| |
| template<class T, size_t N> |
| span(array<T, N>&) -> span<T, N>; |
| |
| template<class T, size_t N> |
| span(const array<T, N>&) -> span<const T, N>; |
| |
| template<class R> |
| span(R&&) -> span<remove_reference_t<ranges::range_reference_t<R>>>; |
| |
| } // namespace std |
| |
| */ |
| |
| #include <__config> |
| #include <__debug> |
| #include <__iterator/concepts.h> |
| #include <__iterator/wrap_iter.h> |
| #include <__ranges/concepts.h> |
| #include <__ranges/data.h> |
| #include <__ranges/enable_borrowed_range.h> |
| #include <__ranges/enable_view.h> |
| #include <__ranges/size.h> |
| #include <array> // for array |
| #include <cstddef> // for byte |
| #include <iterator> // for iterators |
| #include <limits> |
| #include <type_traits> // for remove_cv, etc |
| #include <version> |
| |
| #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) |
| #pragma GCC system_header |
| #endif |
| |
| _LIBCPP_PUSH_MACROS |
| #include <__undef_macros> |
| |
| _LIBCPP_BEGIN_NAMESPACE_STD |
| |
| #if _LIBCPP_STD_VER > 17 |
| |
| inline constexpr size_t dynamic_extent = numeric_limits<size_t>::max(); |
| template <typename _Tp, size_t _Extent = dynamic_extent> class span; |
| |
| |
| template <class _Tp> |
| struct __is_std_array : false_type {}; |
| |
| template <class _Tp, size_t _Sz> |
| struct __is_std_array<array<_Tp, _Sz>> : true_type {}; |
| |
| template <class _Tp> |
| struct __is_std_span : false_type {}; |
| |
| template <class _Tp, size_t _Sz> |
| struct __is_std_span<span<_Tp, _Sz>> : true_type {}; |
| |
| #if !defined(_LIBCPP_HAS_NO_RANGES) |
| template <class _Range, class _ElementType> |
| concept __span_compatible_range = |
| ranges::contiguous_range<_Range> && |
| ranges::sized_range<_Range> && |
| (ranges::borrowed_range<_Range> || is_const_v<_ElementType>) && |
| !__is_std_span<remove_cvref_t<_Range>>::value && |
| !__is_std_array<remove_cvref_t<_Range>>::value && |
| !is_array_v<remove_cvref_t<_Range>> && |
| is_convertible_v<remove_reference_t<ranges::range_reference_t<_Range>>(*)[], _ElementType(*)[]>; |
| #endif |
| |
| template <typename _Tp, size_t _Extent> |
| class _LIBCPP_TEMPLATE_VIS span { |
| public: |
| // constants and types |
| using element_type = _Tp; |
| using value_type = remove_cv_t<_Tp>; |
| using size_type = size_t; |
| using difference_type = ptrdiff_t; |
| using pointer = _Tp *; |
| using const_pointer = const _Tp *; |
| using reference = _Tp &; |
| using const_reference = const _Tp &; |
| #if (_LIBCPP_DEBUG_LEVEL == 2) || defined(_LIBCPP_ABI_SPAN_POINTER_ITERATORS) |
| using iterator = pointer; |
| #else |
| using iterator = __wrap_iter<pointer>; |
| #endif |
| using reverse_iterator = _VSTD::reverse_iterator<iterator>; |
| |
| static constexpr size_type extent = _Extent; |
| |
| // [span.cons], span constructors, copy, assignment, and destructor |
| template <size_t _Sz = _Extent, enable_if_t<_Sz == 0, nullptr_t> = nullptr> |
| _LIBCPP_INLINE_VISIBILITY constexpr span() noexcept : __data{nullptr} {} |
| |
| constexpr span (const span&) noexcept = default; |
| constexpr span& operator=(const span&) noexcept = default; |
| |
| #if !defined(_LIBCPP_HAS_NO_RANGES) |
| template <class _It, |
| enable_if_t<contiguous_iterator<_It> && |
| is_convertible_v<remove_reference_t<iter_reference_t<_It>>(*)[], element_type (*)[]>, |
| nullptr_t> = nullptr> |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr explicit span(_It __first, size_type __count) |
| : __data{_VSTD::to_address(__first)} { |
| (void)__count; |
| _LIBCPP_ASSERT(_Extent == __count, "size mismatch in span's constructor (iterator, len)"); |
| } |
| |
| template < |
| class _It, class _End, |
| enable_if_t<is_convertible_v<remove_reference_t<iter_reference_t<_It> > (*)[], element_type (*)[]> && |
| contiguous_iterator<_It> && sized_sentinel_for<_End, _It> && !is_convertible_v<_End, size_t>, |
| nullptr_t> = nullptr> |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr explicit span(_It __first, _End __last) : __data{_VSTD::to_address(__first)} { |
| (void)__last; |
| _LIBCPP_ASSERT((__last - __first >= 0), "invalid range in span's constructor (iterator, sentinel)"); |
| _LIBCPP_ASSERT(__last - __first == _Extent, |
| "invalid range in span's constructor (iterator, sentinel): last - first != extent"); |
| } |
| #endif |
| |
| _LIBCPP_INLINE_VISIBILITY constexpr span(type_identity_t<element_type> (&__arr)[_Extent]) noexcept : __data{__arr} {} |
| |
| template <class _OtherElementType, |
| enable_if_t<is_convertible_v<_OtherElementType(*)[], element_type (*)[]>, nullptr_t> = nullptr> |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr span(array<_OtherElementType, _Extent>& __arr) noexcept : __data{__arr.data()} {} |
| |
| template <class _OtherElementType, |
| enable_if_t<is_convertible_v<const _OtherElementType(*)[], element_type (*)[]>, nullptr_t> = nullptr> |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr span(const array<_OtherElementType, _Extent>& __arr) noexcept : __data{__arr.data()} {} |
| |
| #if !defined(_LIBCPP_HAS_NO_RANGES) |
| template <__span_compatible_range<element_type> _Range> |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr explicit span(_Range&& __r) : __data{ranges::data(__r)} { |
| _LIBCPP_ASSERT(ranges::size(__r) == _Extent, "size mismatch in span's constructor (range)"); |
| } |
| #endif |
| |
| template <class _OtherElementType> |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr span(const span<_OtherElementType, _Extent>& __other, |
| enable_if_t< |
| is_convertible_v<_OtherElementType(*)[], element_type (*)[]>, |
| nullptr_t> = nullptr) |
| : __data{__other.data()} {} |
| |
| template <class _OtherElementType> |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr explicit span(const span<_OtherElementType, dynamic_extent>& __other, |
| enable_if_t< |
| is_convertible_v<_OtherElementType(*)[], element_type (*)[]>, |
| nullptr_t> = nullptr) noexcept |
| : __data{__other.data()} { _LIBCPP_ASSERT(_Extent == __other.size(), "size mismatch in span's constructor (other span)"); } |
| |
| |
| // ~span() noexcept = default; |
| |
| template <size_t _Count> |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr span<element_type, _Count> first() const noexcept |
| { |
| static_assert(_Count <= _Extent, "Count out of range in span::first()"); |
| return span<element_type, _Count>{data(), _Count}; |
| } |
| |
| template <size_t _Count> |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr span<element_type, _Count> last() const noexcept |
| { |
| static_assert(_Count <= _Extent, "Count out of range in span::last()"); |
| return span<element_type, _Count>{data() + size() - _Count, _Count}; |
| } |
| |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr span<element_type, dynamic_extent> first(size_type __count) const noexcept |
| { |
| _LIBCPP_ASSERT(__count <= size(), "Count out of range in span::first(count)"); |
| return {data(), __count}; |
| } |
| |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr span<element_type, dynamic_extent> last(size_type __count) const noexcept |
| { |
| _LIBCPP_ASSERT(__count <= size(), "Count out of range in span::last(count)"); |
| return {data() + size() - __count, __count}; |
| } |
| |
| template <size_t _Offset, size_t _Count = dynamic_extent> |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr auto subspan() const noexcept |
| -> span<element_type, _Count != dynamic_extent ? _Count : _Extent - _Offset> |
| { |
| static_assert(_Offset <= _Extent, "Offset out of range in span::subspan()"); |
| static_assert(_Count == dynamic_extent || _Count <= _Extent - _Offset, "Offset + count out of range in span::subspan()"); |
| |
| using _ReturnType = span<element_type, _Count != dynamic_extent ? _Count : _Extent - _Offset>; |
| return _ReturnType{data() + _Offset, _Count == dynamic_extent ? size() - _Offset : _Count}; |
| } |
| |
| |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr span<element_type, dynamic_extent> |
| subspan(size_type __offset, size_type __count = dynamic_extent) const noexcept |
| { |
| _LIBCPP_ASSERT(__offset <= size(), "Offset out of range in span::subspan(offset, count)"); |
| _LIBCPP_ASSERT(__count <= size() || __count == dynamic_extent, "Count out of range in span::subspan(offset, count)"); |
| if (__count == dynamic_extent) |
| return {data() + __offset, size() - __offset}; |
| _LIBCPP_ASSERT(__count <= size() - __offset, "Offset + count out of range in span::subspan(offset, count)"); |
| return {data() + __offset, __count}; |
| } |
| |
| _LIBCPP_INLINE_VISIBILITY constexpr size_type size() const noexcept { return _Extent; } |
| _LIBCPP_INLINE_VISIBILITY constexpr size_type size_bytes() const noexcept { return _Extent * sizeof(element_type); } |
| [[nodiscard]] _LIBCPP_INLINE_VISIBILITY constexpr bool empty() const noexcept { return _Extent == 0; } |
| |
| _LIBCPP_INLINE_VISIBILITY constexpr reference operator[](size_type __idx) const noexcept |
| { |
| _LIBCPP_ASSERT(__idx < size(), "span<T,N>[] index out of bounds"); |
| return __data[__idx]; |
| } |
| |
| _LIBCPP_INLINE_VISIBILITY constexpr reference front() const noexcept |
| { |
| _LIBCPP_ASSERT(!empty(), "span<T, N>::front() on empty span"); |
| return __data[0]; |
| } |
| |
| _LIBCPP_INLINE_VISIBILITY constexpr reference back() const noexcept |
| { |
| _LIBCPP_ASSERT(!empty(), "span<T, N>::back() on empty span"); |
| return __data[size()-1]; |
| } |
| |
| _LIBCPP_INLINE_VISIBILITY constexpr pointer data() const noexcept { return __data; } |
| |
| // [span.iter], span iterator support |
| _LIBCPP_INLINE_VISIBILITY constexpr iterator begin() const noexcept { return iterator(data()); } |
| _LIBCPP_INLINE_VISIBILITY constexpr iterator end() const noexcept { return iterator(data() + size()); } |
| _LIBCPP_INLINE_VISIBILITY constexpr reverse_iterator rbegin() const noexcept { return reverse_iterator(end()); } |
| _LIBCPP_INLINE_VISIBILITY constexpr reverse_iterator rend() const noexcept { return reverse_iterator(begin()); } |
| |
| _LIBCPP_INLINE_VISIBILITY span<const byte, _Extent * sizeof(element_type)> __as_bytes() const noexcept |
| { return span<const byte, _Extent * sizeof(element_type)>{reinterpret_cast<const byte *>(data()), size_bytes()}; } |
| |
| _LIBCPP_INLINE_VISIBILITY span<byte, _Extent * sizeof(element_type)> __as_writable_bytes() const noexcept |
| { return span<byte, _Extent * sizeof(element_type)>{reinterpret_cast<byte *>(data()), size_bytes()}; } |
| |
| private: |
| pointer __data; |
| |
| }; |
| |
| |
| template <typename _Tp> |
| class _LIBCPP_TEMPLATE_VIS span<_Tp, dynamic_extent> { |
| private: |
| |
| public: |
| // constants and types |
| using element_type = _Tp; |
| using value_type = remove_cv_t<_Tp>; |
| using size_type = size_t; |
| using difference_type = ptrdiff_t; |
| using pointer = _Tp *; |
| using const_pointer = const _Tp *; |
| using reference = _Tp &; |
| using const_reference = const _Tp &; |
| #if (_LIBCPP_DEBUG_LEVEL == 2) || defined(_LIBCPP_ABI_SPAN_POINTER_ITERATORS) |
| using iterator = pointer; |
| #else |
| using iterator = __wrap_iter<pointer>; |
| #endif |
| using reverse_iterator = _VSTD::reverse_iterator<iterator>; |
| |
| static constexpr size_type extent = dynamic_extent; |
| |
| // [span.cons], span constructors, copy, assignment, and destructor |
| _LIBCPP_INLINE_VISIBILITY constexpr span() noexcept : __data{nullptr}, __size{0} {} |
| |
| constexpr span (const span&) noexcept = default; |
| constexpr span& operator=(const span&) noexcept = default; |
| |
| #if !defined(_LIBCPP_HAS_NO_RANGES) |
| template <class _It, |
| enable_if_t<contiguous_iterator<_It> && |
| is_convertible_v<remove_reference_t<iter_reference_t<_It> > (*)[], element_type (*)[]>, |
| nullptr_t> = nullptr> |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr span(_It __first, size_type __count) |
| : __data{_VSTD::to_address(__first)}, __size{__count} {} |
| |
| template < |
| class _It, class _End, |
| enable_if_t<is_convertible_v<remove_reference_t<iter_reference_t<_It> > (*)[], element_type (*)[]> && |
| contiguous_iterator<_It> && sized_sentinel_for<_End, _It> && !is_convertible_v<_End, size_t>, |
| nullptr_t> = nullptr> |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr span(_It __first, _End __last) |
| : __data(_VSTD::to_address(__first)), __size(__last - __first) {} |
| #endif |
| |
| template <size_t _Sz> |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr span(type_identity_t<element_type> (&__arr)[_Sz]) noexcept : __data{__arr}, __size{_Sz} {} |
| |
| template <class _OtherElementType, size_t _Sz, |
| enable_if_t<is_convertible_v<_OtherElementType(*)[], element_type (*)[]>, nullptr_t> = nullptr> |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr span(array<_OtherElementType, _Sz>& __arr) noexcept : __data{__arr.data()}, __size{_Sz} {} |
| |
| template <class _OtherElementType, size_t _Sz, |
| enable_if_t<is_convertible_v<const _OtherElementType(*)[], element_type (*)[]>, nullptr_t> = nullptr> |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr span(const array<_OtherElementType, _Sz>& __arr) noexcept : __data{__arr.data()}, __size{_Sz} {} |
| |
| #if !defined(_LIBCPP_HAS_NO_RANGES) |
| template <__span_compatible_range<element_type> _Range> |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr span(_Range&& __r) : __data(ranges::data(__r)), __size{ranges::size(__r)} {} |
| # endif |
| |
| template <class _OtherElementType, size_t _OtherExtent> |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr span(const span<_OtherElementType, _OtherExtent>& __other, |
| enable_if_t< |
| is_convertible_v<_OtherElementType(*)[], element_type (*)[]>, |
| nullptr_t> = nullptr) noexcept |
| : __data{__other.data()}, __size{__other.size()} {} |
| |
| // ~span() noexcept = default; |
| |
| template <size_t _Count> |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr span<element_type, _Count> first() const noexcept |
| { |
| _LIBCPP_ASSERT(_Count <= size(), "Count out of range in span::first()"); |
| return span<element_type, _Count>{data(), _Count}; |
| } |
| |
| template <size_t _Count> |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr span<element_type, _Count> last() const noexcept |
| { |
| _LIBCPP_ASSERT(_Count <= size(), "Count out of range in span::last()"); |
| return span<element_type, _Count>{data() + size() - _Count, _Count}; |
| } |
| |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr span<element_type, dynamic_extent> first(size_type __count) const noexcept |
| { |
| _LIBCPP_ASSERT(__count <= size(), "Count out of range in span::first(count)"); |
| return {data(), __count}; |
| } |
| |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr span<element_type, dynamic_extent> last (size_type __count) const noexcept |
| { |
| _LIBCPP_ASSERT(__count <= size(), "Count out of range in span::last(count)"); |
| return {data() + size() - __count, __count}; |
| } |
| |
| template <size_t _Offset, size_t _Count = dynamic_extent> |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr span<element_type, _Count> subspan() const noexcept |
| { |
| _LIBCPP_ASSERT(_Offset <= size(), "Offset out of range in span::subspan()"); |
| _LIBCPP_ASSERT(_Count == dynamic_extent || _Count <= size() - _Offset, "Offset + count out of range in span::subspan()"); |
| return span<element_type, _Count>{data() + _Offset, _Count == dynamic_extent ? size() - _Offset : _Count}; |
| } |
| |
| constexpr span<element_type, dynamic_extent> |
| _LIBCPP_INLINE_VISIBILITY |
| subspan(size_type __offset, size_type __count = dynamic_extent) const noexcept |
| { |
| _LIBCPP_ASSERT(__offset <= size(), "Offset out of range in span::subspan(offset, count)"); |
| _LIBCPP_ASSERT(__count <= size() || __count == dynamic_extent, "count out of range in span::subspan(offset, count)"); |
| if (__count == dynamic_extent) |
| return {data() + __offset, size() - __offset}; |
| _LIBCPP_ASSERT(__count <= size() - __offset, "Offset + count out of range in span::subspan(offset, count)"); |
| return {data() + __offset, __count}; |
| } |
| |
| _LIBCPP_INLINE_VISIBILITY constexpr size_type size() const noexcept { return __size; } |
| _LIBCPP_INLINE_VISIBILITY constexpr size_type size_bytes() const noexcept { return __size * sizeof(element_type); } |
| [[nodiscard]] _LIBCPP_INLINE_VISIBILITY constexpr bool empty() const noexcept { return __size == 0; } |
| |
| _LIBCPP_INLINE_VISIBILITY constexpr reference operator[](size_type __idx) const noexcept |
| { |
| _LIBCPP_ASSERT(__idx < size(), "span<T>[] index out of bounds"); |
| return __data[__idx]; |
| } |
| |
| _LIBCPP_INLINE_VISIBILITY constexpr reference front() const noexcept |
| { |
| _LIBCPP_ASSERT(!empty(), "span<T>[].front() on empty span"); |
| return __data[0]; |
| } |
| |
| _LIBCPP_INLINE_VISIBILITY constexpr reference back() const noexcept |
| { |
| _LIBCPP_ASSERT(!empty(), "span<T>[].back() on empty span"); |
| return __data[size()-1]; |
| } |
| |
| |
| _LIBCPP_INLINE_VISIBILITY constexpr pointer data() const noexcept { return __data; } |
| |
| // [span.iter], span iterator support |
| _LIBCPP_INLINE_VISIBILITY constexpr iterator begin() const noexcept { return iterator(data()); } |
| _LIBCPP_INLINE_VISIBILITY constexpr iterator end() const noexcept { return iterator(data() + size()); } |
| _LIBCPP_INLINE_VISIBILITY constexpr reverse_iterator rbegin() const noexcept { return reverse_iterator(end()); } |
| _LIBCPP_INLINE_VISIBILITY constexpr reverse_iterator rend() const noexcept { return reverse_iterator(begin()); } |
| |
| _LIBCPP_INLINE_VISIBILITY span<const byte, dynamic_extent> __as_bytes() const noexcept |
| { return {reinterpret_cast<const byte *>(data()), size_bytes()}; } |
| |
| _LIBCPP_INLINE_VISIBILITY span<byte, dynamic_extent> __as_writable_bytes() const noexcept |
| { return {reinterpret_cast<byte *>(data()), size_bytes()}; } |
| |
| private: |
| pointer __data; |
| size_type __size; |
| }; |
| |
| #if !defined(_LIBCPP_HAS_NO_RANGES) |
| template <class _Tp, size_t _Extent> |
| inline constexpr bool ranges::enable_borrowed_range<span<_Tp, _Extent> > = true; |
| |
| template <class _ElementType, size_t _Extent> |
| inline constexpr bool ranges::enable_view<span<_ElementType, _Extent>> = true; |
| #endif // !defined(_LIBCPP_HAS_NO_RANGES) |
| |
| // as_bytes & as_writable_bytes |
| template <class _Tp, size_t _Extent> |
| _LIBCPP_INLINE_VISIBILITY |
| auto as_bytes(span<_Tp, _Extent> __s) noexcept |
| -> decltype(__s.__as_bytes()) |
| { return __s.__as_bytes(); } |
| |
| template <class _Tp, size_t _Extent> |
| _LIBCPP_INLINE_VISIBILITY |
| auto as_writable_bytes(span<_Tp, _Extent> __s) noexcept |
| -> enable_if_t<!is_const_v<_Tp>, decltype(__s.__as_writable_bytes())> |
| { return __s.__as_writable_bytes(); } |
| |
| #if !defined(_LIBCPP_HAS_NO_RANGES) |
| // Deduction guides |
| template<contiguous_iterator _It, class _EndOrSize> |
| span(_It, _EndOrSize) -> span<remove_reference_t<iter_reference_t<_It>>>; |
| #endif |
| |
| template<class _Tp, size_t _Sz> |
| span(_Tp (&)[_Sz]) -> span<_Tp, _Sz>; |
| |
| template<class _Tp, size_t _Sz> |
| span(array<_Tp, _Sz>&) -> span<_Tp, _Sz>; |
| |
| template<class _Tp, size_t _Sz> |
| span(const array<_Tp, _Sz>&) -> span<const _Tp, _Sz>; |
| |
| #if !defined(_LIBCPP_HAS_NO_RANGES) |
| template<ranges::contiguous_range _Range> |
| span(_Range&&) -> span<remove_reference_t<ranges::range_reference_t<_Range>>>; |
| #endif |
| |
| #endif // _LIBCPP_STD_VER > 17 |
| |
| _LIBCPP_END_NAMESPACE_STD |
| |
| _LIBCPP_POP_MACROS |
| |
| #endif // _LIBCPP_SPAN |
