592 lines
24 KiB
C++
592 lines
24 KiB
C++
// -*- C++ -*-
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//===------------------------------ span ---------------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===---------------------------------------------------------------------===//
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#ifndef _LIBCPP_SPAN
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#define _LIBCPP_SPAN
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/*
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span synopsis
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namespace std {
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// constants
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inline constexpr size_t dynamic_extent = numeric_limits<size_t>::max();
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// [views.span], class template span
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template <class ElementType, size_t Extent = dynamic_extent>
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class span;
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// [span.objectrep], views of object representation
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template <class ElementType, size_t Extent>
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span<const byte, ((Extent == dynamic_extent) ? dynamic_extent :
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(sizeof(ElementType) * Extent))> as_bytes(span<ElementType, Extent> s) noexcept;
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template <class ElementType, size_t Extent>
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span< byte, ((Extent == dynamic_extent) ? dynamic_extent :
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(sizeof(ElementType) * Extent))> as_writable_bytes(span<ElementType, Extent> s) noexcept;
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namespace std {
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template <class ElementType, size_t Extent = dynamic_extent>
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class span {
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public:
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// constants and types
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using element_type = ElementType;
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using value_type = remove_cv_t<ElementType>;
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using index_type = size_t;
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using difference_type = ptrdiff_t;
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using pointer = element_type*;
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using const_pointer = const element_type*;
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using reference = element_type&;
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using const_reference = const element_type&;
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using iterator = implementation-defined;
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using const_iterator = implementation-defined;
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using reverse_iterator = std::reverse_iterator<iterator>;
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using const_reverse_iterator = std::reverse_iterator<const_iterator>;
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static constexpr index_type extent = Extent;
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// [span.cons], span constructors, copy, assignment, and destructor
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constexpr span() noexcept;
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constexpr span(pointer ptr, index_type count);
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constexpr span(pointer firstElem, pointer lastElem);
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template <size_t N>
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constexpr span(element_type (&arr)[N]) noexcept;
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template <size_t N>
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constexpr span(array<value_type, N>& arr) noexcept;
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template <size_t N>
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constexpr span(const array<value_type, N>& arr) noexcept;
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template <class Container>
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constexpr span(Container& cont);
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template <class Container>
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constexpr span(const Container& cont);
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constexpr span(const span& other) noexcept = default;
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template <class OtherElementType, size_t OtherExtent>
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constexpr span(const span<OtherElementType, OtherExtent>& s) noexcept;
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~span() noexcept = default;
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constexpr span& operator=(const span& other) noexcept = default;
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// [span.sub], span subviews
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template <size_t Count>
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constexpr span<element_type, Count> first() const;
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template <size_t Count>
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constexpr span<element_type, Count> last() const;
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template <size_t Offset, size_t Count = dynamic_extent>
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constexpr span<element_type, see below> subspan() const;
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constexpr span<element_type, dynamic_extent> first(index_type count) const;
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constexpr span<element_type, dynamic_extent> last(index_type count) const;
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constexpr span<element_type, dynamic_extent> subspan(index_type offset, index_type count = dynamic_extent) const;
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// [span.obs], span observers
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constexpr index_type size() const noexcept;
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constexpr index_type size_bytes() const noexcept;
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constexpr bool empty() const noexcept;
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// [span.elem], span element access
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constexpr reference operator[](index_type idx) const;
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constexpr reference front() const;
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constexpr reference back() const;
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constexpr pointer data() const noexcept;
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// [span.iterators], span iterator support
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constexpr iterator begin() const noexcept;
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constexpr iterator end() const noexcept;
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constexpr const_iterator cbegin() const noexcept;
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constexpr const_iterator cend() const noexcept;
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constexpr reverse_iterator rbegin() const noexcept;
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constexpr reverse_iterator rend() const noexcept;
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constexpr const_reverse_iterator crbegin() const noexcept;
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constexpr const_reverse_iterator crend() const noexcept;
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private:
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pointer data_; // exposition only
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index_type size_; // exposition only
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};
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template<class T, size_t N>
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span(T (&)[N]) -> span<T, N>;
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template<class T, size_t N>
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span(array<T, N>&) -> span<T, N>;
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template<class T, size_t N>
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span(const array<T, N>&) -> span<const T, N>;
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template<class Container>
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span(Container&) -> span<typename Container::value_type>;
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template<class Container>
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span(const Container&) -> span<const typename Container::value_type>;
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} // namespace std
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*/
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#include <__config>
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#include <cstddef> // for ptrdiff_t
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#include <iterator> // for iterators
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#include <array> // for array
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#include <type_traits> // for remove_cv, etc
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#include <cstddef> // for byte
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#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
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#pragma GCC system_header
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#endif
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_LIBCPP_BEGIN_NAMESPACE_STD
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#if _LIBCPP_STD_VER > 17
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inline constexpr size_t dynamic_extent = numeric_limits<size_t>::max();
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template <typename _Tp, size_t _Extent = dynamic_extent> class span;
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template <class _Tp>
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struct __is_span_impl : public false_type {};
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template <class _Tp, size_t _Extent>
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struct __is_span_impl<span<_Tp, _Extent>> : public true_type {};
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template <class _Tp>
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struct __is_span : public __is_span_impl<remove_cv_t<_Tp>> {};
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template <class _Tp>
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struct __is_std_array_impl : public false_type {};
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template <class _Tp, size_t _Sz>
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struct __is_std_array_impl<array<_Tp, _Sz>> : public true_type {};
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template <class _Tp>
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struct __is_std_array : public __is_std_array_impl<remove_cv_t<_Tp>> {};
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template <class _Tp, class _ElementType, class = void>
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struct __is_span_compatible_container : public false_type {};
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template <class _Tp, class _ElementType>
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struct __is_span_compatible_container<_Tp, _ElementType,
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void_t<
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// is not a specialization of span
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typename enable_if<!__is_span<_Tp>::value, nullptr_t>::type,
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// is not a specialization of array
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typename enable_if<!__is_std_array<_Tp>::value, nullptr_t>::type,
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// is_array_v<Container> is false,
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typename enable_if<!is_array_v<_Tp>, nullptr_t>::type,
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// data(cont) and size(cont) are well formed
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decltype(data(declval<_Tp>())),
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decltype(size(declval<_Tp>())),
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// remove_pointer_t<decltype(data(cont))>(*)[] is convertible to ElementType(*)[]
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typename enable_if<
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is_convertible_v<remove_pointer_t<decltype(data(declval<_Tp &>()))>(*)[],
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_ElementType(*)[]>,
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nullptr_t>::type
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>>
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: public true_type {};
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template <typename _Tp, size_t _Extent>
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class _LIBCPP_TEMPLATE_VIS span {
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public:
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// constants and types
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using element_type = _Tp;
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using value_type = remove_cv_t<_Tp>;
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using index_type = size_t;
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using difference_type = ptrdiff_t;
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using pointer = _Tp *;
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using const_pointer = const _Tp *;
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using reference = _Tp &;
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using const_reference = const _Tp &;
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using iterator = __wrap_iter<pointer>;
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using const_iterator = __wrap_iter<const_pointer>;
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using reverse_iterator = _VSTD::reverse_iterator<iterator>;
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using const_reverse_iterator = _VSTD::reverse_iterator<const_iterator>;
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static constexpr index_type extent = _Extent;
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// [span.cons], span constructors, copy, assignment, and destructor
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_LIBCPP_INLINE_VISIBILITY constexpr span() noexcept : __data{nullptr}
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{ static_assert(_Extent == 0, "Can't default construct a statically sized span with size > 0"); }
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constexpr span (const span&) noexcept = default;
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constexpr span& operator=(const span&) noexcept = default;
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_LIBCPP_INLINE_VISIBILITY constexpr span(pointer __ptr, index_type __count) : __data{__ptr}
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{ (void)__count; _LIBCPP_ASSERT(_Extent == __count, "size mismatch in span's constructor (ptr, len)"); }
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_LIBCPP_INLINE_VISIBILITY constexpr span(pointer __f, pointer __l) : __data{__f}
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{ (void)__l; _LIBCPP_ASSERT(_Extent == distance(__f, __l), "size mismatch in span's constructor (ptr, ptr)"); }
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_LIBCPP_INLINE_VISIBILITY constexpr span(element_type (&__arr)[_Extent]) noexcept : __data{__arr} {}
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_LIBCPP_INLINE_VISIBILITY constexpr span( array<value_type, _Extent>& __arr) noexcept : __data{__arr.data()} {}
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_LIBCPP_INLINE_VISIBILITY constexpr span(const array<value_type, _Extent>& __arr) noexcept : __data{__arr.data()} {}
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template <class _OtherElementType>
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_LIBCPP_INLINE_VISIBILITY
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constexpr span(const span<_OtherElementType, _Extent>& __other,
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enable_if_t<
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is_convertible_v<_OtherElementType(*)[], element_type (*)[]>,
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nullptr_t> = nullptr)
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: __data{__other.data()} {}
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template <class _OtherElementType>
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_LIBCPP_INLINE_VISIBILITY
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constexpr span(const span<_OtherElementType, dynamic_extent>& __other,
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enable_if_t<
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is_convertible_v<_OtherElementType(*)[], element_type (*)[]>,
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nullptr_t> = nullptr) noexcept
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: __data{__other.data()} { _LIBCPP_ASSERT(_Extent == __other.size(), "size mismatch in span's constructor (other span)"); }
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// ~span() noexcept = default;
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template <size_t _Count>
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_LIBCPP_INLINE_VISIBILITY
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constexpr span<element_type, _Count> first() const noexcept
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{
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static_assert(_Count <= _Extent, "Count out of range in span::first()");
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return {data(), _Count};
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}
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template <size_t _Count>
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_LIBCPP_INLINE_VISIBILITY
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constexpr span<element_type, _Count> last() const noexcept
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{
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static_assert(_Count <= _Extent, "Count out of range in span::last()");
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return {data() + size() - _Count, _Count};
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}
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_LIBCPP_INLINE_VISIBILITY
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constexpr span<element_type, dynamic_extent> first(index_type __count) const noexcept
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{
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_LIBCPP_ASSERT(__count <= size(), "Count out of range in span::first(count)");
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return {data(), __count};
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}
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_LIBCPP_INLINE_VISIBILITY
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constexpr span<element_type, dynamic_extent> last(index_type __count) const noexcept
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{
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_LIBCPP_ASSERT(__count <= size(), "Count out of range in span::last(count)");
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return {data() + size() - __count, __count};
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}
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template <size_t _Offset, size_t _Count = dynamic_extent>
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_LIBCPP_INLINE_VISIBILITY
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constexpr auto subspan() const noexcept
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-> span<element_type, _Count != dynamic_extent ? _Count : _Extent - _Offset>
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{
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static_assert(_Offset <= _Extent, "Offset out of range in span::subspan()");
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return {data() + _Offset, _Count == dynamic_extent ? size() - _Offset : _Count};
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}
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_LIBCPP_INLINE_VISIBILITY
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constexpr span<element_type, dynamic_extent>
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subspan(index_type __offset, index_type __count = dynamic_extent) const noexcept
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{
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_LIBCPP_ASSERT(__offset <= size(), "Offset out of range in span::subspan(offset, count)");
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_LIBCPP_ASSERT(__count <= size() || __count == dynamic_extent, "Count out of range in span::subspan(offset, count)");
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if (__count == dynamic_extent)
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return {data() + __offset, size() - __offset};
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_LIBCPP_ASSERT(__offset <= size() - __count, "count + offset out of range in span::subspan(offset, count)");
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return {data() + __offset, __count};
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}
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_LIBCPP_INLINE_VISIBILITY constexpr index_type size() const noexcept { return _Extent; }
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_LIBCPP_INLINE_VISIBILITY constexpr index_type size_bytes() const noexcept { return _Extent * sizeof(element_type); }
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_LIBCPP_INLINE_VISIBILITY constexpr bool empty() const noexcept { return _Extent == 0; }
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_LIBCPP_INLINE_VISIBILITY constexpr reference operator[](index_type __idx) const noexcept
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{
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_LIBCPP_ASSERT(__idx >= 0 && __idx < size(), "span<T,N>[] index out of bounds");
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return __data[__idx];
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}
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_LIBCPP_INLINE_VISIBILITY constexpr reference front() const noexcept
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{
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static_assert(_Extent > 0, "span<T,N>[].front() on empty span");
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return __data[0];
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}
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_LIBCPP_INLINE_VISIBILITY constexpr reference back() const noexcept
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{
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static_assert(_Extent > 0, "span<T,N>[].back() on empty span");
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return __data[size()-1];
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}
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_LIBCPP_INLINE_VISIBILITY constexpr pointer data() const noexcept { return __data; }
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// [span.iter], span iterator support
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_LIBCPP_INLINE_VISIBILITY constexpr iterator begin() const noexcept { return iterator(data()); }
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_LIBCPP_INLINE_VISIBILITY constexpr iterator end() const noexcept { return iterator(data() + size()); }
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_LIBCPP_INLINE_VISIBILITY constexpr const_iterator cbegin() const noexcept { return const_iterator(data()); }
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_LIBCPP_INLINE_VISIBILITY constexpr const_iterator cend() const noexcept { return const_iterator(data() + size()); }
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_LIBCPP_INLINE_VISIBILITY constexpr reverse_iterator rbegin() const noexcept { return reverse_iterator(end()); }
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_LIBCPP_INLINE_VISIBILITY constexpr reverse_iterator rend() const noexcept { return reverse_iterator(begin()); }
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_LIBCPP_INLINE_VISIBILITY constexpr const_reverse_iterator crbegin() const noexcept { return const_reverse_iterator(cend()); }
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_LIBCPP_INLINE_VISIBILITY constexpr const_reverse_iterator crend() const noexcept { return const_reverse_iterator(cbegin()); }
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_LIBCPP_INLINE_VISIBILITY constexpr void swap(span &__other) noexcept
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{
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pointer __p = __data;
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__data = __other.__data;
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__other.__data = __p;
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}
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_LIBCPP_INLINE_VISIBILITY span<const byte, _Extent * sizeof(element_type)> __as_bytes() const noexcept
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{ return {reinterpret_cast<const byte *>(data()), size_bytes()}; }
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_LIBCPP_INLINE_VISIBILITY span<byte, _Extent * sizeof(element_type)> __as_writable_bytes() const noexcept
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{ return {reinterpret_cast<byte *>(data()), size_bytes()}; }
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private:
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pointer __data;
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};
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template <typename _Tp>
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class _LIBCPP_TEMPLATE_VIS span<_Tp, dynamic_extent> {
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private:
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public:
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// constants and types
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using element_type = _Tp;
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using value_type = remove_cv_t<_Tp>;
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using index_type = size_t;
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using difference_type = ptrdiff_t;
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using pointer = _Tp *;
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using const_pointer = const _Tp *;
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using reference = _Tp &;
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using const_reference = const _Tp &;
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using iterator = __wrap_iter<pointer>;
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using const_iterator = __wrap_iter<const_pointer>;
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using reverse_iterator = _VSTD::reverse_iterator<iterator>;
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using const_reverse_iterator = _VSTD::reverse_iterator<const_iterator>;
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static constexpr index_type extent = dynamic_extent;
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// [span.cons], span constructors, copy, assignment, and destructor
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_LIBCPP_INLINE_VISIBILITY constexpr span() noexcept : __data{nullptr}, __size{0} {}
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constexpr span (const span&) noexcept = default;
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constexpr span& operator=(const span&) noexcept = default;
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_LIBCPP_INLINE_VISIBILITY constexpr span(pointer __ptr, index_type __count) : __data{__ptr}, __size{__count} {}
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_LIBCPP_INLINE_VISIBILITY constexpr span(pointer __f, pointer __l) : __data{__f}, __size{static_cast<size_t>(distance(__f, __l))} {}
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template <size_t _Sz>
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_LIBCPP_INLINE_VISIBILITY
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constexpr span(element_type (&__arr)[_Sz]) noexcept : __data{__arr}, __size{_Sz} {}
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template <size_t _Sz>
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_LIBCPP_INLINE_VISIBILITY
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constexpr span(array<value_type, _Sz>& __arr) noexcept : __data{__arr.data()}, __size{_Sz} {}
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template <size_t _Sz>
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_LIBCPP_INLINE_VISIBILITY
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constexpr span(const array<value_type, _Sz>& __arr) noexcept : __data{__arr.data()}, __size{_Sz} {}
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template <class _Container>
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_LIBCPP_INLINE_VISIBILITY
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constexpr span( _Container& __c,
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enable_if_t<__is_span_compatible_container<_Container, _Tp>::value, nullptr_t> = nullptr)
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: __data{_VSTD::data(__c)}, __size{(index_type) _VSTD::size(__c)} {}
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template <class _Container>
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_LIBCPP_INLINE_VISIBILITY
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constexpr span(const _Container& __c,
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enable_if_t<__is_span_compatible_container<const _Container, _Tp>::value, nullptr_t> = nullptr)
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: __data{_VSTD::data(__c)}, __size{(index_type) _VSTD::size(__c)} {}
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template <class _OtherElementType, size_t _OtherExtent>
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_LIBCPP_INLINE_VISIBILITY
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constexpr span(const span<_OtherElementType, _OtherExtent>& __other,
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enable_if_t<
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is_convertible_v<_OtherElementType(*)[], element_type (*)[]>,
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nullptr_t> = nullptr) noexcept
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: __data{__other.data()}, __size{__other.size()} {}
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// ~span() noexcept = default;
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template <size_t _Count>
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_LIBCPP_INLINE_VISIBILITY
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constexpr span<element_type, _Count> first() const noexcept
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{
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_LIBCPP_ASSERT(_Count <= size(), "Count out of range in span::first()");
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return {data(), _Count};
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}
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template <size_t _Count>
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_LIBCPP_INLINE_VISIBILITY
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constexpr span<element_type, _Count> last() const noexcept
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{
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_LIBCPP_ASSERT(_Count <= size(), "Count out of range in span::last()");
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return {data() + size() - _Count, _Count};
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}
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_LIBCPP_INLINE_VISIBILITY
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constexpr span<element_type, dynamic_extent> first(index_type __count) const noexcept
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{
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_LIBCPP_ASSERT(__count <= size(), "Count out of range in span::first(count)");
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return {data(), __count};
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}
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_LIBCPP_INLINE_VISIBILITY
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constexpr span<element_type, dynamic_extent> last (index_type __count) const noexcept
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{
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_LIBCPP_ASSERT(__count <= size(), "Count out of range in span::last(count)");
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return {data() + size() - __count, __count};
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}
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template <size_t _Offset, size_t _Count = dynamic_extent>
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_LIBCPP_INLINE_VISIBILITY
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constexpr span<_Tp, dynamic_extent> subspan() const noexcept
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|
{
|
|
_LIBCPP_ASSERT(_Offset <= size(), "Offset out of range in span::subspan()");
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|
_LIBCPP_ASSERT(_Count == dynamic_extent || _Offset + _Count <= size(), "Count out of range in span::subspan()");
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return {data() + _Offset, _Count == dynamic_extent ? size() - _Offset : _Count};
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}
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|
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constexpr span<element_type, dynamic_extent>
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|
_LIBCPP_INLINE_VISIBILITY
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|
subspan(index_type __offset, index_type __count = dynamic_extent) const noexcept
|
|
{
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|
_LIBCPP_ASSERT(__offset <= size(), "Offset out of range in span::subspan(offset, count)");
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|
_LIBCPP_ASSERT(__count <= size() || __count == dynamic_extent, "count out of range in span::subspan(offset, count)");
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|
if (__count == dynamic_extent)
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|
return {data() + __offset, size() - __offset};
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|
_LIBCPP_ASSERT(__offset <= size() - __count, "Offset + count out of range in span::subspan(offset, count)");
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|
return {data() + __offset, __count};
|
|
}
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|
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|
_LIBCPP_INLINE_VISIBILITY constexpr index_type size() const noexcept { return __size; }
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|
_LIBCPP_INLINE_VISIBILITY constexpr index_type size_bytes() const noexcept { return __size * sizeof(element_type); }
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|
_LIBCPP_INLINE_VISIBILITY constexpr bool empty() const noexcept { return __size == 0; }
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|
|
|
_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];
|
|
}
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|
|
|
_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 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_writable_bytes() const noexcept
|
|
{ return {reinterpret_cast<byte *>(data()), size_bytes()}; }
|
|
|
|
private:
|
|
pointer __data;
|
|
index_type __size;
|
|
};
|
|
|
|
// tuple interface
|
|
template <class _Tp, size_t _Size>
|
|
struct _LIBCPP_TEMPLATE_VIS tuple_size<span<_Tp, _Size>>
|
|
: public integral_constant<size_t, _Size> {};
|
|
|
|
template <class _Tp>
|
|
struct _LIBCPP_TEMPLATE_VIS tuple_size<span<_Tp, dynamic_extent>>; // declared but not defined
|
|
|
|
|
|
template <size_t _Ip, class _Tp, size_t _Size>
|
|
struct _LIBCPP_TEMPLATE_VIS tuple_element<_Ip, span<_Tp, _Size>>
|
|
{
|
|
static_assert( dynamic_extent != _Size, "std::tuple_element<> not supported for std::span<T, dynamic_extent>");
|
|
static_assert(_Ip < _Size, "Index out of bounds in std::tuple_element<> (std::span)");
|
|
typedef _Tp type;
|
|
};
|
|
|
|
template <size_t _Ip, class _Tp, size_t _Size>
|
|
_LIBCPP_INLINE_VISIBILITY constexpr
|
|
_Tp&
|
|
get(span<_Tp, _Size> __s) noexcept
|
|
{
|
|
static_assert( dynamic_extent != _Size, "std::get<> not supported for std::span<T, dynamic_extent>");
|
|
static_assert(_Ip < _Size, "Index out of bounds in std::get<> (std::span)");
|
|
return __s[_Ip];
|
|
}
|
|
|
|
|
|
// 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(); }
|
|
|
|
template <class _Tp, size_t _Extent>
|
|
_LIBCPP_INLINE_VISIBILITY
|
|
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
|