Remove old code

Signed-off-by: Richard Qin <richard.qin.x@gmail.com>

1 files changed, 0 insertions, 662 deletions

diff --git a/third_party/libcxx/include/c++/v1/span b/third_party/libcxx/include/c++/v1/span
deleted file mode 100644
index 1911bad..0000000
--- a/third_party/libcxx/include/c++/v1/span
+++ /dev/null
@@ -1,662 +0,0 @@
-// -*- 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();
-
-template<class T>
-  concept integral-constant-like =                           // exposition only, since C++26
-    is_integral_v<decltype(T::value)> &&
-    !is_same_v<bool, remove_const_t<decltype(T::value)>> &&
-    convertible_to<T, decltype(T::value)> &&
-    equality_comparable_with<T, decltype(T::value)> &&
-    bool_constant<T() == T::value>::value &&
-    bool_constant<static_cast<decltype(T::value)>(T()) == T::value>::value;
-
-template<class T>
-  constexpr size_t maybe-static-ext = dynamic_extent;        // exposition only, since C++26
-template<integral-constant-like T>
-  constexpr size_t maybe-static-ext<T> = {T::value};
-
-// [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 explicit(extent != dynamic_extent) span(std::initializer_list<value_type> il); // Since C++26
-    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;
-    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 at(size_type idx) const; // since C++26
-    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>>>;                             // until C++26
-template<class It, class EndOrSize>
-    span(It, EndOrSize) -> span<remove_reference_t<iter_reference_t<It>>, maybe-static-ext<EndOrSize>>; // since C++26
-
-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
-
-*/
-
-#if __cplusplus < 201103L && defined(_LIBCPP_USE_FROZEN_CXX03_HEADERS)
-#  include <__cxx03/__config>
-#else
-#  include <__assert>
-#  include <__concepts/convertible_to.h>
-#  include <__concepts/equality_comparable.h>
-#  include <__config>
-#  include <__cstddef/byte.h>
-#  include <__cstddef/ptrdiff_t.h>
-#  include <__fwd/array.h>
-#  include <__fwd/span.h>
-#  include <__iterator/bounded_iter.h>
-#  include <__iterator/concepts.h>
-#  include <__iterator/iterator_traits.h>
-#  include <__iterator/reverse_iterator.h>
-#  include <__iterator/wrap_iter.h>
-#  include <__memory/pointer_traits.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 <__type_traits/integral_constant.h>
-#  include <__type_traits/is_array.h>
-#  include <__type_traits/is_const.h>
-#  include <__type_traits/is_convertible.h>
-#  include <__type_traits/is_integral.h>
-#  include <__type_traits/is_same.h>
-#  include <__type_traits/remove_const.h>
-#  include <__type_traits/remove_cv.h>
-#  include <__type_traits/remove_cvref.h>
-#  include <__type_traits/remove_reference.h>
-#  include <__type_traits/type_identity.h>
-#  include <__utility/forward.h>
-#  include <initializer_list>
-#  include <stdexcept>
-#  include <version>
-
-// standard-mandated includes
-
-// [iterator.range]
-#  include <__iterator/access.h>
-#  include <__iterator/data.h>
-#  include <__iterator/empty.h>
-#  include <__iterator/reverse_access.h>
-#  include <__iterator/size.h>
-
-#  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 >= 20
-
-template <class _Tp>
-struct __is_std_span : false_type {};
-
-template <class _Tp, size_t _Sz>
-struct __is_std_span<span<_Tp, _Sz>> : true_type {};
-
-template <class _Range, class _ElementType>
-concept __span_compatible_range =
-    !__is_std_span<remove_cvref_t<_Range>>::value &&                //
-    ranges::contiguous_range<_Range> &&                             //
-    ranges::sized_range<_Range> &&                                  //
-    (ranges::borrowed_range<_Range> || is_const_v<_ElementType>) && //
-    !__is_std_array_v<remove_cvref_t<_Range>> &&                    //
-    !is_array_v<remove_cvref_t<_Range>> &&                          //
-    is_convertible_v<remove_reference_t<ranges::range_reference_t<_Range>> (*)[], _ElementType (*)[]>;
-
-template <class _From, class _To>
-concept __span_array_convertible = is_convertible_v<_From (*)[], _To (*)[]>;
-
-template <class _It, class _Tp>
-concept __span_compatible_iterator =
-    contiguous_iterator<_It> && __span_array_convertible<remove_reference_t<iter_reference_t<_It>>, _Tp>;
-
-template <class _Sentinel, class _It>
-concept __span_compatible_sentinel_for = sized_sentinel_for<_Sentinel, _It> && !is_convertible_v<_Sentinel, size_t>;
-
-template <typename _Tp, size_t _Extent>
-class 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&;
-#    ifdef _LIBCPP_ABI_BOUNDED_ITERATORS
-  using iterator = __bounded_iter<pointer>;
-#    else
-  using iterator = __wrap_iter<pointer>;
-#    endif
-  using reverse_iterator = std::reverse_iterator<iterator>;
-
-  static constexpr size_type extent = _Extent;
-
-  // [span.cons], span constructors, copy, assignment, and destructor
-  template <size_t _Sz = _Extent>
-    requires(_Sz == 0)
-  _LIBCPP_HIDE_FROM_ABI constexpr span() noexcept : __data_{nullptr} {}
-
-#    if _LIBCPP_STD_VER >= 26
-  _LIBCPP_HIDE_FROM_ABI constexpr explicit span(std::initializer_list<value_type> __il)
-    requires is_const_v<element_type>
-      : __data_{__il.begin()} {
-    _LIBCPP_ASSERT_VALID_INPUT_RANGE(
-        _Extent == __il.size(), "Size mismatch in span's constructor _Extent != __il.size().");
-  }
-#    endif
-
-  constexpr span(const span&) noexcept            = default;
-  constexpr span& operator=(const span&) noexcept = default;
-
-  template <__span_compatible_iterator<element_type> _It>
-  _LIBCPP_HIDE_FROM_ABI constexpr explicit span(_It __first, size_type __count) : __data_{std::to_address(__first)} {
-    (void)__count;
-    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(_Extent == __count, "size mismatch in span's constructor (iterator, len)");
-    _LIBCPP_ASSERT_VALID_INPUT_RANGE(__count == 0 || std::to_address(__first) != nullptr,
-                                     "passed nullptr with non-zero length in span's constructor (iterator, len)");
-  }
-
-  template <__span_compatible_iterator<element_type> _It, __span_compatible_sentinel_for<_It> _End>
-  _LIBCPP_HIDE_FROM_ABI constexpr explicit span(_It __first, _End __last) : __data_{std::to_address(__first)} {
-    // [span.cons]/10
-    // Throws: When and what last - first throws.
-    [[maybe_unused]] auto __dist = __last - __first;
-    _LIBCPP_ASSERT_VALID_INPUT_RANGE(__dist >= 0, "invalid range in span's constructor (iterator, sentinel)");
-    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
-        __dist == _Extent, "invalid range in span's constructor (iterator, sentinel): last - first != extent");
-  }
-
-  _LIBCPP_HIDE_FROM_ABI constexpr span(type_identity_t<element_type> (&__arr)[_Extent]) noexcept : __data_{__arr} {}
-
-  template <__span_array_convertible<element_type> _OtherElementType>
-  _LIBCPP_HIDE_FROM_ABI constexpr span(array<_OtherElementType, _Extent>& __arr) noexcept : __data_{__arr.data()} {}
-
-  template <class _OtherElementType>
-    requires __span_array_convertible<const _OtherElementType, element_type>
-  _LIBCPP_HIDE_FROM_ABI constexpr span(const array<_OtherElementType, _Extent>& __arr) noexcept
-      : __data_{__arr.data()} {}
-
-  template <__span_compatible_range<element_type> _Range>
-  _LIBCPP_HIDE_FROM_ABI constexpr explicit span(_Range&& __r) : __data_{ranges::data(__r)} {
-    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(ranges::size(__r) == _Extent, "size mismatch in span's constructor (range)");
-  }
-
-  template <__span_array_convertible<element_type> _OtherElementType>
-  _LIBCPP_HIDE_FROM_ABI constexpr span(const span<_OtherElementType, _Extent>& __other) noexcept
-      : __data_{__other.data()} {}
-
-  template <__span_array_convertible<element_type> _OtherElementType>
-  _LIBCPP_HIDE_FROM_ABI constexpr explicit span(const span<_OtherElementType, dynamic_extent>& __other) noexcept
-      : __data_{__other.data()} {
-    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(_Extent == __other.size(), "size mismatch in span's constructor (other span)");
-  }
-
-  template <size_t _Count>
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, _Count> first() const noexcept {
-    static_assert(_Count <= _Extent, "span<T, N>::first<Count>(): Count out of range");
-    return span<element_type, _Count>{data(), _Count};
-  }
-
-  template <size_t _Count>
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, _Count> last() const noexcept {
-    static_assert(_Count <= _Extent, "span<T, N>::last<Count>(): Count out of range");
-    return span<element_type, _Count>{data() + size() - _Count, _Count};
-  }
-
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, dynamic_extent>
-  first(size_type __count) const noexcept {
-    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__count <= size(), "span<T, N>::first(count): count out of range");
-    return {data(), __count};
-  }
-
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, dynamic_extent>
-  last(size_type __count) const noexcept {
-    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__count <= size(), "span<T, N>::last(count): count out of range");
-    return {data() + size() - __count, __count};
-  }
-
-  template <size_t _Offset, size_t _Count = dynamic_extent>
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto subspan() const noexcept
-      -> span<element_type, _Count != dynamic_extent ? _Count : _Extent - _Offset> {
-    static_assert(_Offset <= _Extent, "span<T, N>::subspan<Offset, Count>(): Offset out of range");
-    static_assert(_Count == dynamic_extent || _Count <= _Extent - _Offset,
-                  "span<T, N>::subspan<Offset, Count>(): Offset + Count out of range");
-
-    using _ReturnType = span<element_type, _Count != dynamic_extent ? _Count : _Extent - _Offset>;
-    return _ReturnType{data() + _Offset, _Count == dynamic_extent ? size() - _Offset : _Count};
-  }
-
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, dynamic_extent>
-  subspan(size_type __offset, size_type __count = dynamic_extent) const noexcept {
-    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__offset <= size(), "span<T, N>::subspan(offset, count): offset out of range");
-    if (__count == dynamic_extent)
-      return {data() + __offset, size() - __offset};
-    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
-        __count <= size() - __offset, "span<T, N>::subspan(offset, count): offset + count out of range");
-    return {data() + __offset, __count};
-  }
-
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr size_type size() const noexcept { return _Extent; }
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr size_type size_bytes() const noexcept {
-    return _Extent * sizeof(element_type);
-  }
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool empty() const noexcept { return _Extent == 0; }
-
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr reference operator[](size_type __idx) const noexcept {
-    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__idx < size(), "span<T, N>::operator[](index): index out of range");
-    return __data_[__idx];
-  }
-
-#    if _LIBCPP_STD_VER >= 26
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr reference at(size_type __index) const {
-    if (__index >= size())
-      std::__throw_out_of_range("span");
-    return __data_[__index];
-  }
-#    endif
-
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr reference front() const noexcept {
-    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "span<T, N>::front() on empty span");
-    return __data_[0];
-  }
-
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr reference back() const noexcept {
-    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "span<T, N>::back() on empty span");
-    return __data_[size() - 1];
-  }
-
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr pointer data() const noexcept { return __data_; }
-
-  // [span.iter], span iterator support
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr iterator begin() const noexcept {
-#    ifdef _LIBCPP_ABI_BOUNDED_ITERATORS
-    return std::__make_bounded_iter(data(), data(), data() + size());
-#    else
-    return iterator(data());
-#    endif
-  }
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr iterator end() const noexcept {
-#    ifdef _LIBCPP_ABI_BOUNDED_ITERATORS
-    return std::__make_bounded_iter(data() + size(), data(), data() + size());
-#    else
-    return iterator(data() + size());
-#    endif
-  }
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr reverse_iterator rbegin() const noexcept {
-    return reverse_iterator(end());
-  }
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr reverse_iterator rend() const noexcept {
-    return reverse_iterator(begin());
-  }
-
-  _LIBCPP_HIDE_FROM_ABI 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_HIDE_FROM_ABI 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 span<_Tp, dynamic_extent> {
-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&;
-#    ifdef _LIBCPP_ABI_BOUNDED_ITERATORS
-  using iterator = __bounded_iter<pointer>;
-#    else
-  using iterator = __wrap_iter<pointer>;
-#    endif
-  using reverse_iterator = std::reverse_iterator<iterator>;
-
-  static constexpr size_type extent = dynamic_extent;
-
-  // [span.cons], span constructors, copy, assignment, and destructor
-  _LIBCPP_HIDE_FROM_ABI constexpr span() noexcept : __data_{nullptr}, __size_{0} {}
-
-#    if _LIBCPP_STD_VER >= 26
-  _LIBCPP_HIDE_FROM_ABI constexpr span(std::initializer_list<value_type> __il)
-    requires is_const_v<element_type>
-      : __data_{__il.begin()}, __size_{__il.size()} {}
-#    endif
-
-  constexpr span(const span&) noexcept            = default;
-  constexpr span& operator=(const span&) noexcept = default;
-
-  template <__span_compatible_iterator<element_type> _It>
-  _LIBCPP_HIDE_FROM_ABI constexpr span(_It __first, size_type __count)
-      : __data_{std::to_address(__first)}, __size_{__count} {
-    _LIBCPP_ASSERT_VALID_INPUT_RANGE(__count == 0 || std::to_address(__first) != nullptr,
-                                     "passed nullptr with non-zero length in span's constructor (iterator, len)");
-  }
-
-  template <__span_compatible_iterator<element_type> _It, __span_compatible_sentinel_for<_It> _End>
-  _LIBCPP_HIDE_FROM_ABI constexpr span(_It __first, _End __last)
-      : __data_(std::to_address(__first)), __size_(__last - __first) {
-    _LIBCPP_ASSERT_VALID_INPUT_RANGE(__last - __first >= 0, "invalid range in span's constructor (iterator, sentinel)");
-  }
-
-  template <size_t _Sz>
-  _LIBCPP_HIDE_FROM_ABI constexpr span(type_identity_t<element_type> (&__arr)[_Sz]) noexcept
-      : __data_{__arr}, __size_{_Sz} {}
-
-  template <__span_array_convertible<element_type> _OtherElementType, size_t _Sz>
-  _LIBCPP_HIDE_FROM_ABI constexpr span(array<_OtherElementType, _Sz>& __arr) noexcept
-      : __data_{__arr.data()}, __size_{_Sz} {}
-
-  template <class _OtherElementType, size_t _Sz>
-    requires __span_array_convertible<const _OtherElementType, element_type>
-  _LIBCPP_HIDE_FROM_ABI constexpr span(const array<_OtherElementType, _Sz>& __arr) noexcept
-      : __data_{__arr.data()}, __size_{_Sz} {}
-
-  template <__span_compatible_range<element_type> _Range>
-  _LIBCPP_HIDE_FROM_ABI constexpr span(_Range&& __r) : __data_(ranges::data(__r)), __size_{ranges::size(__r)} {}
-
-  template <__span_array_convertible<element_type> _OtherElementType, size_t _OtherExtent>
-  _LIBCPP_HIDE_FROM_ABI constexpr span(const span<_OtherElementType, _OtherExtent>& __other) noexcept
-      : __data_{__other.data()}, __size_{__other.size()} {}
-
-  template <size_t _Count>
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, _Count> first() const noexcept {
-    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(_Count <= size(), "span<T>::first<Count>(): Count out of range");
-    return span<element_type, _Count>{data(), _Count};
-  }
-
-  template <size_t _Count>
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, _Count> last() const noexcept {
-    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(_Count <= size(), "span<T>::last<Count>(): Count out of range");
-    return span<element_type, _Count>{data() + size() - _Count, _Count};
-  }
-
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, dynamic_extent>
-  first(size_type __count) const noexcept {
-    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__count <= size(), "span<T>::first(count): count out of range");
-    return {data(), __count};
-  }
-
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, dynamic_extent>
-  last(size_type __count) const noexcept {
-    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__count <= size(), "span<T>::last(count): count out of range");
-    return {data() + size() - __count, __count};
-  }
-
-  template <size_t _Offset, size_t _Count = dynamic_extent>
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, _Count> subspan() const noexcept {
-    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(_Offset <= size(), "span<T>::subspan<Offset, Count>(): Offset out of range");
-    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(_Count == dynamic_extent || _Count <= size() - _Offset,
-                                        "span<T>::subspan<Offset, Count>(): Offset + Count out of range");
-    return span<element_type, _Count>{data() + _Offset, _Count == dynamic_extent ? size() - _Offset : _Count};
-  }
-
-  [[nodiscard]] constexpr span<element_type, dynamic_extent> _LIBCPP_HIDE_FROM_ABI
-  subspan(size_type __offset, size_type __count = dynamic_extent) const noexcept {
-    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__offset <= size(), "span<T>::subspan(offset, count): offset out of range");
-    if (__count == dynamic_extent)
-      return {data() + __offset, size() - __offset};
-    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
-        __count <= size() - __offset, "span<T>::subspan(offset, count): offset + count out of range");
-    return {data() + __offset, __count};
-  }
-
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr size_type size() const noexcept { return __size_; }
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr size_type size_bytes() const noexcept {
-    return __size_ * sizeof(element_type);
-  }
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool empty() const noexcept { return __size_ == 0; }
-
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr reference operator[](size_type __idx) const noexcept {
-    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__idx < size(), "span<T>::operator[](index): index out of range");
-    return __data_[__idx];
-  }
-
-#    if _LIBCPP_STD_VER >= 26
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr reference at(size_type __index) const {
-    if (__index >= size())
-      std::__throw_out_of_range("span");
-    return __data_[__index];
-  }
-#    endif
-
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr reference front() const noexcept {
-    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "span<T>::front() on empty span");
-    return __data_[0];
-  }
-
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr reference back() const noexcept {
-    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "span<T>::back() on empty span");
-    return __data_[size() - 1];
-  }
-
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr pointer data() const noexcept { return __data_; }
-
-  // [span.iter], span iterator support
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr iterator begin() const noexcept {
-#    ifdef _LIBCPP_ABI_BOUNDED_ITERATORS
-    return std::__make_bounded_iter(data(), data(), data() + size());
-#    else
-    return iterator(data());
-#    endif
-  }
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr iterator end() const noexcept {
-#    ifdef _LIBCPP_ABI_BOUNDED_ITERATORS
-    return std::__make_bounded_iter(data() + size(), data(), data() + size());
-#    else
-    return iterator(data() + size());
-#    endif
-  }
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr reverse_iterator rbegin() const noexcept {
-    return reverse_iterator(end());
-  }
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr reverse_iterator rend() const noexcept {
-    return reverse_iterator(begin());
-  }
-
-  _LIBCPP_HIDE_FROM_ABI span<const byte, dynamic_extent> __as_bytes() const noexcept {
-    return {reinterpret_cast<const byte*>(data()), size_bytes()};
-  }
-
-  _LIBCPP_HIDE_FROM_ABI span<byte, dynamic_extent> __as_writable_bytes() const noexcept {
-    return {reinterpret_cast<byte*>(data()), size_bytes()};
-  }
-
-private:
-  pointer __data_;
-  size_type __size_;
-};
-
-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;
-
-//  as_bytes & as_writable_bytes
-template <class _Tp, size_t _Extent>
-[[nodiscard]] _LIBCPP_HIDE_FROM_ABI auto as_bytes(span<_Tp, _Extent> __s) noexcept {
-  return __s.__as_bytes();
-}
-
-template <class _Tp, size_t _Extent>
-  requires(!is_const_v<_Tp>)
-[[nodiscard]] _LIBCPP_HIDE_FROM_ABI auto as_writable_bytes(span<_Tp, _Extent> __s) noexcept {
-  return __s.__as_writable_bytes();
-}
-
-#    if _LIBCPP_STD_VER >= 26
-template <class _Tp>
-concept __integral_constant_like =
-    is_integral_v<decltype(_Tp::value)> && !is_same_v<bool, remove_const_t<decltype(_Tp::value)>> &&
-    convertible_to<_Tp, decltype(_Tp::value)> && equality_comparable_with<_Tp, decltype(_Tp::value)> &&
-    bool_constant<_Tp() == _Tp::value>::value &&
-    bool_constant<static_cast<decltype(_Tp::value)>(_Tp()) == _Tp::value>::value;
-
-template <class _Tp>
-inline constexpr size_t __maybe_static_ext = dynamic_extent;
-
-template <__integral_constant_like _Tp>
-inline constexpr size_t __maybe_static_ext<_Tp> = {_Tp::value};
-
-template <contiguous_iterator _It, class _EndOrSize>
-span(_It, _EndOrSize) -> span<remove_reference_t<iter_reference_t<_It>>, __maybe_static_ext<_EndOrSize>>;
-#    else
-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>;
-
-template <ranges::contiguous_range _Range>
-span(_Range&&) -> span<remove_reference_t<ranges::range_reference_t<_Range>>>;
-
-#  endif // _LIBCPP_STD_VER >= 20
-
-_LIBCPP_END_NAMESPACE_STD
-
-_LIBCPP_POP_MACROS
-
-#  if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
-#    include <array>
-#    include <concepts>
-#    include <functional>
-#    include <iterator>
-#    include <type_traits>
-#  endif
-#endif // __cplusplus < 201103L && defined(_LIBCPP_USE_FROZEN_CXX03_HEADERS)
-
-#endif // _LIBCPP_SPAN