| // -*- C++ -*- |
| //===------------------------------ span ---------------------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is dual licensed under the MIT and the University of Illinois Open |
| // Source Licenses. See LICENSE.TXT for details. |
| // |
| //===---------------------------------------------------------------------===// |
| |
| #ifndef _LIBCPP_SPAN |
| #define _LIBCPP_SPAN |
| |
| /* |
| span synopsis |
| |
| namespace std { |
| |
| // constants |
| inline constexpr ptrdiff_t dynamic_extent = -1; |
| |
| // [views.span], class template span |
| template <class ElementType, ptrdiff_t Extent = dynamic_extent> |
| class span; |
| |
| // [span.comparison], span comparison operators |
| template <class T, ptrdiff_t X, class U, ptrdiff_t Y> |
| constexpr bool operator==(span<T, X> l, span<U, Y> r); |
| template <class T, ptrdiff_t X, class U, ptrdiff_t Y> |
| constexpr bool operator!=(span<T, X> l, span<U, Y> r); |
| template <class T, ptrdiff_t X, class U, ptrdiff_t Y> |
| constexpr bool operator<(span<T, X> l, span<U, Y> r); |
| template <class T, ptrdiff_t X, class U, ptrdiff_t Y> |
| constexpr bool operator<=(span<T, X> l, span<U, Y> r); |
| template <class T, ptrdiff_t X, class U, ptrdiff_t Y> |
| constexpr bool operator>(span<T, X> l, span<U, Y> r); |
| template <class T, ptrdiff_t X, class U, ptrdiff_t Y> |
| constexpr bool operator>=(span<T, X> l, span<U, Y> r); |
| |
| // [span.objectrep], views of object representation |
| template <class ElementType, ptrdiff_t Extent> |
| span<const byte, ((Extent == dynamic_extent) ? dynamic_extent : |
| (static_cast<ptrdiff_t>(sizeof(ElementType)) * Extent))> as_bytes(span<ElementType, Extent> s) noexcept; |
| |
| template <class ElementType, ptrdiff_t Extent> |
| span< byte, ((Extent == dynamic_extent) ? dynamic_extent : |
| (static_cast<ptrdiff_t>(sizeof(ElementType)) * Extent))> as_writable_bytes(span<ElementType, Extent> s) noexcept; |
| |
| |
| namespace std { |
| template <class ElementType, ptrdiff_t Extent = dynamic_extent> |
| class span { |
| public: |
| // constants and types |
| using element_type = ElementType; |
| using value_type = remove_cv_t<ElementType>; |
| using index_type = ptrdiff_t; |
| using difference_type = ptrdiff_t; |
| using pointer = element_type*; |
| using reference = element_type&; |
| using iterator = implementation-defined; |
| using const_iterator = implementation-defined; |
| using reverse_iterator = std::reverse_iterator<iterator>; |
| using const_reverse_iterator = std::reverse_iterator<const_iterator>; |
| static constexpr index_type extent = Extent; |
| |
| // [span.cons], span constructors, copy, assignment, and destructor |
| constexpr span() noexcept; |
| constexpr span(pointer ptr, index_type count); |
| constexpr span(pointer firstElem, pointer lastElem); |
| template <size_t N> |
| constexpr span(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 Container> |
| constexpr span(Container& cont); |
| template <class Container> |
| constexpr span(const Container& cont); |
| constexpr span(const span& other) noexcept = default; |
| template <class OtherElementType, ptrdiff_t OtherExtent> |
| constexpr span(const span<OtherElementType, OtherExtent>& s) noexcept; |
| ~span() noexcept = default; |
| constexpr span& operator=(const span& other) noexcept = default; |
| |
| // [span.sub], span subviews |
| template <ptrdiff_t Count> |
| constexpr span<element_type, Count> first() const; |
| template <ptrdiff_t Count> |
| constexpr span<element_type, Count> last() const; |
| template <ptrdiff_t Offset, ptrdiff_t Count = dynamic_extent> |
| constexpr span<element_type, see below> subspan() const; |
| |
| constexpr span<element_type, dynamic_extent> first(index_type count) const; |
| constexpr span<element_type, dynamic_extent> last(index_type count) const; |
| constexpr span<element_type, dynamic_extent> subspan(index_type offset, index_type count = dynamic_extent) const; |
| |
| // [span.obs], span observers |
| constexpr index_type size() const noexcept; |
| constexpr index_type size_bytes() const noexcept; |
| constexpr bool empty() const noexcept; |
| |
| // [span.elem], span element access |
| constexpr reference operator[](index_type idx) const; |
| constexpr reference operator()(index_type idx) const; |
| constexpr pointer data() const noexcept; |
| |
| // [span.iterators], span iterator support |
| constexpr iterator begin() const noexcept; |
| constexpr iterator end() const noexcept; |
| constexpr const_iterator cbegin() const noexcept; |
| constexpr const_iterator cend() const noexcept; |
| constexpr reverse_iterator rbegin() const noexcept; |
| constexpr reverse_iterator rend() const noexcept; |
| constexpr const_reverse_iterator crbegin() const noexcept; |
| constexpr const_reverse_iterator crend() const noexcept; |
| |
| private: |
| pointer data_; // exposition only |
| index_type size_; // exposition only |
| }; |
| |
| 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 Container> |
| span(Container&) -> span<typename Container::value_type>; |
| |
| template<class Container> |
| span(const Container&) -> span<const typename Container::value_type>; |
| |
| } // namespace std |
| |
| */ |
| |
| #include <__config> |
| #include <cstddef> // for ptrdiff_t |
| #include <iterator> // for iterators |
| #include <array> // for array |
| #include <type_traits> // for remove_cv, etc |
| #include <cstddef> // for byte |
| |
| #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) |
| #pragma GCC system_header |
| #endif |
| |
| _LIBCPP_BEGIN_NAMESPACE_STD |
| |
| #if _LIBCPP_STD_VER > 17 |
| |
| inline constexpr ptrdiff_t dynamic_extent = -1; |
| template <typename _Tp, ptrdiff_t _Extent = dynamic_extent> class span; |
| |
| |
| template <class _Tp> |
| struct __is_span_impl : public false_type {}; |
| |
| template <class _Tp, ptrdiff_t _Extent> |
| struct __is_span_impl<span<_Tp, _Extent>> : public true_type {}; |
| |
| template <class _Tp> |
| struct __is_span : public __is_span_impl<remove_cv_t<_Tp>> {}; |
| |
| template <class _Tp> |
| struct __is_std_array_impl : public false_type {}; |
| |
| template <class _Tp, size_t _Sz> |
| struct __is_std_array_impl<array<_Tp, _Sz>> : public true_type {}; |
| |
| template <class _Tp> |
| struct __is_std_array : public __is_std_array_impl<remove_cv_t<_Tp>> {}; |
| |
| template <class _Tp, class _ElementType, class = void> |
| struct __is_span_compatible_container : public false_type {}; |
| |
| template <class _Tp, class _ElementType> |
| struct __is_span_compatible_container<_Tp, _ElementType, |
| void_t< |
| // is not a specialization of span |
| typename enable_if<!__is_span<_Tp>::value, nullptr_t>::type, |
| // is not a specialization of array |
| typename enable_if<!__is_std_array<_Tp>::value, nullptr_t>::type, |
| // is_array_v<Container> is false, |
| typename enable_if<!is_array_v<_Tp>, nullptr_t>::type, |
| // data(cont) and size(cont) are well formed |
| decltype(data(declval<_Tp>())), |
| decltype(size(declval<_Tp>())), |
| // remove_pointer_t<decltype(data(cont))>(*)[] is convertible to ElementType(*)[] |
| typename enable_if< |
| is_convertible_v<remove_pointer_t<decltype(data(declval<_Tp &>()))>(*)[], |
| _ElementType(*)[]>, |
| nullptr_t>::type |
| >> |
| : public true_type {}; |
| |
| |
| template <typename _Tp, ptrdiff_t _Extent> |
| class _LIBCPP_TEMPLATE_VIS span { |
| public: |
| // constants and types |
| using element_type = _Tp; |
| using value_type = remove_cv_t<_Tp>; |
| using index_type = ptrdiff_t; |
| using difference_type = ptrdiff_t; |
| using pointer = _Tp *; |
| using const_pointer = const _Tp *; // not in standard |
| using reference = _Tp &; |
| using const_reference = const _Tp &; // not in standard |
| using iterator = __wrap_iter<pointer>; |
| using const_iterator = __wrap_iter<const_pointer>; |
| using reverse_iterator = _VSTD::reverse_iterator<iterator>; |
| using const_reverse_iterator = _VSTD::reverse_iterator<const_iterator>; |
| |
| static constexpr index_type extent = _Extent; |
| static_assert (_Extent >= 0, "Can't have a span with an extent < 0"); |
| |
| // [span.cons], span constructors, copy, assignment, and destructor |
| _LIBCPP_INLINE_VISIBILITY constexpr span() noexcept : __data{nullptr} |
| { static_assert(_Extent == 0, "Can't default construct a statically sized span with size > 0"); } |
| |
| constexpr span (const span&) noexcept = default; |
| constexpr span& operator=(const span&) noexcept = default; |
| |
| _LIBCPP_INLINE_VISIBILITY constexpr span(pointer __ptr, index_type __count) : __data{__ptr} |
| { (void)__count; _LIBCPP_ASSERT(_Extent == __count, "size mismatch in span's constructor (ptr, len)"); } |
| _LIBCPP_INLINE_VISIBILITY constexpr span(pointer __f, pointer __l) : __data{__f} |
| { (void)__l; _LIBCPP_ASSERT(_Extent == distance(__f, __l), "size mismatch in span's constructor (ptr, ptr)"); } |
| |
| _LIBCPP_INLINE_VISIBILITY constexpr span(element_type (&__arr)[_Extent]) noexcept : __data{__arr} {} |
| _LIBCPP_INLINE_VISIBILITY constexpr span( array<value_type, _Extent>& __arr) noexcept : __data{__arr.data()} {} |
| _LIBCPP_INLINE_VISIBILITY constexpr span(const array<value_type, _Extent>& __arr) noexcept : __data{__arr.data()} {} |
| |
| template <class _Container> |
| inline _LIBCPP_INLINE_VISIBILITY |
| constexpr span( _Container& __c, |
| enable_if_t<__is_span_compatible_container<_Container, _Tp>::value, nullptr_t> = nullptr) |
| : __data{_VSTD::data(__c)} |
| { _LIBCPP_ASSERT(_Extent == _VSTD::size(__c), "size mismatch in span's constructor (container)"); } |
| |
| template <class _Container> |
| inline _LIBCPP_INLINE_VISIBILITY |
| constexpr span(const _Container& __c, |
| enable_if_t<__is_span_compatible_container<const _Container, _Tp>::value, nullptr_t> = nullptr) |
| : __data{_VSTD::data(__c)} |
| { _LIBCPP_ASSERT(_Extent == _VSTD::size(__c), "size mismatch in span's constructor (const container)"); } |
| |
| template <class _OtherElementType> |
| inline _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> |
| inline _LIBCPP_INLINE_VISIBILITY |
| constexpr 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 <ptrdiff_t _Count> |
| inline _LIBCPP_INLINE_VISIBILITY |
| constexpr span<element_type, _Count> first() const noexcept |
| { |
| static_assert(_Count >= 0, "Count must be >= 0 in span::first()"); |
| static_assert(_Count <= _Extent, "Count out of range in span::first()"); |
| return {data(), _Count}; |
| } |
| |
| template <ptrdiff_t _Count> |
| inline _LIBCPP_INLINE_VISIBILITY |
| constexpr span<element_type, _Count> last() const noexcept |
| { |
| static_assert(_Count >= 0, "Count must be >= 0 in span::last()"); |
| static_assert(_Count <= _Extent, "Count out of range in span::last()"); |
| return {data() + size() - _Count, _Count}; |
| } |
| |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr span<element_type, dynamic_extent> first(index_type __count) const noexcept |
| { |
| _LIBCPP_ASSERT(__count >= 0 && __count <= size(), "Count out of range in span::first(count)"); |
| return {data(), __count}; |
| } |
| |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr span<element_type, dynamic_extent> last(index_type __count) const noexcept |
| { |
| _LIBCPP_ASSERT(__count >= 0 && __count <= size(), "Count out of range in span::last(count)"); |
| return {data() + size() - __count, __count}; |
| } |
| |
| template <ptrdiff_t _Offset, ptrdiff_t _Count = dynamic_extent> |
| inline _LIBCPP_INLINE_VISIBILITY |
| constexpr auto subspan() const noexcept |
| -> span<element_type, _Count != dynamic_extent ? _Count : _Extent - _Offset> |
| { |
| _LIBCPP_ASSERT(_Offset >= 0 && _Offset <= size(), "Offset out of range in span::subspan()"); |
| return {data() + _Offset, _Count == dynamic_extent ? size() - _Offset : _Count}; |
| } |
| |
| |
| inline _LIBCPP_INLINE_VISIBILITY |
| constexpr span<element_type, dynamic_extent> |
| subspan(index_type __offset, index_type __count = dynamic_extent) const noexcept |
| { |
| _LIBCPP_ASSERT( __offset >= 0 && __offset <= size(), "Offset out of range in span::subspan(offset, count)"); |
| _LIBCPP_ASSERT((__count >= 0 && __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(__offset + __count <= size(), "count + offset out of range in span::subspan(offset, count)"); |
| return {data() + __offset, __count}; |
| } |
| |
| _LIBCPP_INLINE_VISIBILITY constexpr index_type size() const noexcept { return _Extent; } |
| _LIBCPP_INLINE_VISIBILITY constexpr index_type size_bytes() const noexcept { return _Extent * sizeof(element_type); } |
| _LIBCPP_INLINE_VISIBILITY constexpr bool empty() const noexcept { return _Extent == 0; } |
| |
| _LIBCPP_INLINE_VISIBILITY constexpr reference operator[](index_type __idx) const noexcept |
| { |
| _LIBCPP_ASSERT(__idx >= 0 && __idx < size(), "span<T,N>[] index out of bounds"); |
| return __data[__idx]; |
| } |
| |
| _LIBCPP_INLINE_VISIBILITY constexpr reference operator()(index_type __idx) const noexcept |
| { |
| _LIBCPP_ASSERT(__idx >= 0 && __idx < size(), "span<T,N>() index out of bounds"); |
| return __data[__idx]; |
| } |
| |
| _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 const_iterator cbegin() const noexcept { return const_iterator(data()); } |
| _LIBCPP_INLINE_VISIBILITY constexpr const_iterator cend() const noexcept { return const_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 constexpr const_reverse_iterator crbegin() const noexcept { return const_reverse_iterator(cend()); } |
| _LIBCPP_INLINE_VISIBILITY constexpr const_reverse_iterator crend() const noexcept { return const_reverse_iterator(cbegin()); } |
| |
| _LIBCPP_INLINE_VISIBILITY constexpr void swap(span &__other) noexcept |
| { |
| pointer __p = __data; |
| __data = __other.__data; |
| __other.__data = __p; |
| } |
| |
| _LIBCPP_INLINE_VISIBILITY span<const byte, _Extent * sizeof(element_type)> __as_bytes() const noexcept |
| { return {reinterpret_cast<const byte *>(data()), size_bytes()}; } |
| |
| _LIBCPP_INLINE_VISIBILITY span<byte, _Extent * sizeof(element_type)> __as_writeable_bytes() const noexcept |
| { return {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 index_type = ptrdiff_t; |
| using difference_type = ptrdiff_t; |
| using pointer = _Tp *; |
| using const_pointer = const _Tp *; // not in standard |
| using reference = _Tp &; |
| using const_reference = const _Tp &; // not in standard |
| using iterator = __wrap_iter<pointer>; |
| using const_iterator = __wrap_iter<const_pointer>; |
| using reverse_iterator = _VSTD::reverse_iterator<iterator>; |
| using const_reverse_iterator = _VSTD::reverse_iterator<const_iterator>; |
| |
| static constexpr index_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; |
| |
| _LIBCPP_INLINE_VISIBILITY constexpr span(pointer __ptr, index_type __count) : __data{__ptr}, __size{__count} {} |
| _LIBCPP_INLINE_VISIBILITY constexpr span(pointer __f, pointer __l) : __data{__f}, __size{distance(__f, __l)} {} |
| |
| template <size_t _Sz> |
| inline _LIBCPP_INLINE_VISIBILITY |
| constexpr span(element_type (&__arr)[_Sz]) noexcept : __data{__arr}, __size{_Sz} {} |
| |
| template <size_t _Sz> |
| inline _LIBCPP_INLINE_VISIBILITY |
| constexpr span(array<value_type, _Sz>& __arr) noexcept : __data{__arr.data()}, __size{_Sz} {} |
| |
| template <size_t _Sz> |
| inline _LIBCPP_INLINE_VISIBILITY |
| constexpr span(const array<value_type, _Sz>& __arr) noexcept : __data{__arr.data()}, __size{_Sz} {} |
| |
| template <class _Container> |
| inline _LIBCPP_INLINE_VISIBILITY |
| constexpr span( _Container& __c, |
| enable_if_t<__is_span_compatible_container<_Container, _Tp>::value, nullptr_t> = nullptr) |
| : __data{_VSTD::data(__c)}, __size{(index_type) _VSTD::size(__c)} {} |
| |
| template <class _Container> |
| inline _LIBCPP_INLINE_VISIBILITY |
| constexpr span(const _Container& __c, |
| enable_if_t<__is_span_compatible_container<const _Container, _Tp>::value, nullptr_t> = nullptr) |
| : __data{_VSTD::data(__c)}, __size{(index_type) _VSTD::size(__c)} {} |
| |
| |
| template <class _OtherElementType, ptrdiff_t _OtherExtent> |
| inline _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 <ptrdiff_t _Count> |
| inline _LIBCPP_INLINE_VISIBILITY |
| constexpr span<element_type, _Count> first() const noexcept |
| { |
| static_assert(_Count >= 0, "Count must be >= 0 in span::first()"); |
| _LIBCPP_ASSERT(_Count <= size(), "Count out of range in span::first()"); |
| return {data(), _Count}; |
| } |
| |
| template <ptrdiff_t _Count> |
| inline _LIBCPP_INLINE_VISIBILITY |
| constexpr span<element_type, _Count> last() const noexcept |
| { |
| static_assert(_Count >= 0, "Count must be >= 0 in span::last()"); |
| _LIBCPP_ASSERT(_Count <= size(), "Count out of range in span::last()"); |
| return {data() + size() - _Count, _Count}; |
| } |
| |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr span<element_type, dynamic_extent> first(index_type __count) const noexcept |
| { |
| _LIBCPP_ASSERT(__count >= 0 && __count <= size(), "Count out of range in span::first(count)"); |
| return {data(), __count}; |
| } |
| |
| _LIBCPP_INLINE_VISIBILITY |
| constexpr span<element_type, dynamic_extent> last (index_type __count) const noexcept |
| { |
| _LIBCPP_ASSERT(__count >= 0 && __count <= size(), "Count out of range in span::last(count)"); |
| return {data() + size() - __count, __count}; |
| } |
| |
| template <ptrdiff_t _Offset, ptrdiff_t _Count = dynamic_extent> |
| inline _LIBCPP_INLINE_VISIBILITY |
| constexpr span<_Tp, dynamic_extent> subspan() const noexcept |
| { |
| _LIBCPP_ASSERT(_Offset >= 0 && _Offset <= size(), "Offset out of range in span::subspan()"); |
| _LIBCPP_ASSERT(_Count == dynamic_extent || _Offset + _Count <= size(), "Count out of range in span::subspan()"); |
| return {data() + _Offset, _Count == dynamic_extent ? size() - _Offset : _Count}; |
| } |
| |
| constexpr span<element_type, dynamic_extent> |
| inline _LIBCPP_INLINE_VISIBILITY |
| subspan(index_type __offset, index_type __count = dynamic_extent) const noexcept |
| { |
| _LIBCPP_ASSERT( __offset >= 0 && __offset <= size(), "Offset out of range in span::subspan(offset, count)"); |
| _LIBCPP_ASSERT((__count >= 0 && __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(__offset + __count <= size(), "Offset + count out of range in span::subspan(offset, count)"); |
| return {data() + __offset, __count}; |
| } |
| |
| _LIBCPP_INLINE_VISIBILITY constexpr index_type size() const noexcept { return __size; } |
| _LIBCPP_INLINE_VISIBILITY constexpr index_type size_bytes() const noexcept { return __size * sizeof(element_type); } |
| _LIBCPP_INLINE_VISIBILITY constexpr bool empty() const noexcept { return __size == 0; } |
| |
| _LIBCPP_INLINE_VISIBILITY constexpr reference operator[](index_type __idx) const noexcept |
| { |
| _LIBCPP_ASSERT(__idx >= 0 && __idx < size(), "span<T>[] index out of bounds"); |
| return __data[__idx]; |
| } |
| |
| _LIBCPP_INLINE_VISIBILITY constexpr reference operator()(index_type __idx) const noexcept |
| { |
| _LIBCPP_ASSERT(__idx >= 0 && __idx < size(), "span<T>() index out of bounds"); |
| return __data[__idx]; |
| } |
| |
| _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 const_iterator cbegin() const noexcept { return const_iterator(data()); } |
| _LIBCPP_INLINE_VISIBILITY constexpr const_iterator cend() const noexcept { return const_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 constexpr const_reverse_iterator crbegin() const noexcept { return const_reverse_iterator(cend()); } |
| _LIBCPP_INLINE_VISIBILITY constexpr const_reverse_iterator crend() const noexcept { return const_reverse_iterator(cbegin()); } |
| |
| _LIBCPP_INLINE_VISIBILITY constexpr void swap(span &__other) noexcept |
| { |
| pointer __p = __data; |
| __data = __other.__data; |
| __other.__data = __p; |
| |
| index_type __sz = __size; |
| __size = __other.__size; |
| __other.__size = __sz; |
| } |
| |
| _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_writeable_bytes() const noexcept |
| { return {reinterpret_cast<byte *>(data()), size_bytes()}; } |
| |
| private: |
| pointer __data; |
| index_type __size; |
| }; |
| |
| template <class _Tp1, ptrdiff_t _Extent1, class _Tp2, ptrdiff_t _Extent2> |
| constexpr bool |
| operator==(const span<_Tp1, _Extent1>& __lhs, const span<_Tp2, _Extent2>& __rhs) |
| { return equal(__lhs.begin(), __lhs.end(), __rhs.begin(), __rhs.end()); } |
| |
| template <class _Tp1, ptrdiff_t _Extent1, class _Tp2, ptrdiff_t _Extent2> |
| constexpr bool |
| operator!=(const span<_Tp1, _Extent1>& __lhs, const span<_Tp2, _Extent2>& __rhs) |
| { return !(__rhs == __lhs); } |
| |
| template <class _Tp1, ptrdiff_t _Extent1, class _Tp2, ptrdiff_t _Extent2> |
| constexpr bool |
| operator< (const span<_Tp1, _Extent1>& __lhs, const span<_Tp2, _Extent2>& __rhs) |
| { return lexicographical_compare (__lhs.begin(), __lhs.end(), __rhs.begin(), __rhs.end()); } |
| |
| template <class _Tp1, ptrdiff_t _Extent1, class _Tp2, ptrdiff_t _Extent2> |
| constexpr bool |
| operator<=(const span<_Tp1, _Extent1>& __lhs, const span<_Tp2, _Extent2>& __rhs) |
| { return !(__rhs < __lhs); } |
| |
| template <class _Tp1, ptrdiff_t _Extent1, class _Tp2, ptrdiff_t _Extent2> |
| constexpr bool |
| operator> (const span<_Tp1, _Extent1>& __lhs, const span<_Tp2, _Extent2>& __rhs) |
| { return __rhs < __lhs; } |
| |
| template <class _Tp1, ptrdiff_t _Extent1, class _Tp2, ptrdiff_t _Extent2> |
| constexpr bool |
| operator>=(const span<_Tp1, _Extent1>& __lhs, const span<_Tp2, _Extent2>& __rhs) |
| { return !(__lhs < __rhs); } |
| |
| // as_bytes & as_writeable_bytes |
| template <class _Tp, ptrdiff_t _Extent> |
| auto as_bytes(span<_Tp, _Extent> __s) noexcept |
| -> decltype(__s.__as_bytes()) |
| { return __s.__as_bytes(); } |
| |
| template <class _Tp, ptrdiff_t _Extent> |
| auto as_writeable_bytes(span<_Tp, _Extent> __s) noexcept |
| -> typename enable_if<!is_const_v<_Tp>, decltype(__s.__as_writeable_bytes())>::type |
| { return __s.__as_writeable_bytes(); } |
| |
| template <class _Tp, ptrdiff_t _Extent> |
| constexpr void swap(span<_Tp, _Extent> &__lhs, span<_Tp, _Extent> &__rhs) noexcept |
| { __lhs.swap(__rhs); } |
| |
| |
| // Deduction guides |
| 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>; |
| |
| template<class _Container> |
| span(_Container&) -> span<typename _Container::value_type>; |
| |
| template<class _Container> |
| span(const _Container&) -> span<const typename _Container::value_type>; |
| |
| #endif // _LIBCPP_STD_VER > 17 |
| |
| _LIBCPP_END_NAMESPACE_STD |
| |
| #endif // _LIBCPP_SPAN |