487 lines
17 KiB
C++
487 lines
17 KiB
C++
// -*- C++ -*-
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//===---------------------------- array -----------------------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is dual licensed under the MIT and the University of Illinois Open
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// Source Licenses. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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#ifndef _LIBCPP_ARRAY
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#define _LIBCPP_ARRAY
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/*
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array synopsis
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namespace std
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{
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template <class T, size_t N >
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struct array
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{
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// types:
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typedef T & reference;
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typedef const T & const_reference;
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typedef implementation defined iterator;
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typedef implementation defined const_iterator;
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typedef size_t size_type;
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typedef ptrdiff_t difference_type;
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typedef T value_type;
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typedef T* pointer;
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typedef const T* const_pointer;
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typedef std::reverse_iterator<iterator> reverse_iterator;
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typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
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// No explicit construct/copy/destroy for aggregate type
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void fill(const T& u);
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void swap(array& a) noexcept(is_nothrow_swappable_v<T>);
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// iterators:
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iterator begin() noexcept;
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const_iterator begin() const noexcept;
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iterator end() noexcept;
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const_iterator end() const noexcept;
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reverse_iterator rbegin() noexcept;
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const_reverse_iterator rbegin() const noexcept;
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reverse_iterator rend() noexcept;
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const_reverse_iterator rend() const noexcept;
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const_iterator cbegin() const noexcept;
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const_iterator cend() const noexcept;
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const_reverse_iterator crbegin() const noexcept;
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const_reverse_iterator crend() const noexcept;
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// capacity:
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constexpr size_type size() const noexcept;
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constexpr size_type max_size() const noexcept;
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constexpr bool empty() const noexcept;
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// element access:
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reference operator[](size_type n);
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const_reference operator[](size_type n) const; // constexpr in C++14
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const_reference at(size_type n) const; // constexpr in C++14
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reference at(size_type n);
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reference front();
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const_reference front() const; // constexpr in C++14
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reference back();
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const_reference back() const; // constexpr in C++14
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T* data() noexcept;
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const T* data() const noexcept;
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};
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template <class T, class... U>
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array(T, U...) -> array<T, 1 + sizeof...(U)>;
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template <class T, size_t N>
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bool operator==(const array<T,N>& x, const array<T,N>& y);
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template <class T, size_t N>
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bool operator!=(const array<T,N>& x, const array<T,N>& y);
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template <class T, size_t N>
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bool operator<(const array<T,N>& x, const array<T,N>& y);
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template <class T, size_t N>
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bool operator>(const array<T,N>& x, const array<T,N>& y);
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template <class T, size_t N>
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bool operator<=(const array<T,N>& x, const array<T,N>& y);
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template <class T, size_t N>
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bool operator>=(const array<T,N>& x, const array<T,N>& y);
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template <class T, size_t N >
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void swap(array<T,N>& x, array<T,N>& y) noexcept(noexcept(x.swap(y))); // C++17
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template <class T> struct tuple_size;
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template <size_t I, class T> class tuple_element;
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template <class T, size_t N> struct tuple_size<array<T, N>>;
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template <size_t I, class T, size_t N> struct tuple_element<I, array<T, N>>;
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template <size_t I, class T, size_t N> T& get(array<T, N>&) noexcept; // constexpr in C++14
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template <size_t I, class T, size_t N> const T& get(const array<T, N>&) noexcept; // constexpr in C++14
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template <size_t I, class T, size_t N> T&& get(array<T, N>&&) noexcept; // constexpr in C++14
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template <size_t I, class T, size_t N> const T&& get(const array<T, N>&&) noexcept; // constexpr in C++14
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} // std
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*/
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#include <__config>
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#include <__tuple>
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#include <type_traits>
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#include <utility>
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#include <iterator>
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#include <algorithm>
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#include <stdexcept>
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#include <cstdlib> // for _LIBCPP_UNREACHABLE
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#include <version>
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#include <__debug>
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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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template <class _Tp, size_t _Size>
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struct _LIBCPP_TEMPLATE_VIS array
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{
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// types:
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typedef array __self;
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typedef _Tp value_type;
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typedef value_type& reference;
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typedef const value_type& const_reference;
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typedef value_type* iterator;
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typedef const value_type* const_iterator;
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typedef value_type* pointer;
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typedef const value_type* const_pointer;
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typedef size_t size_type;
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typedef ptrdiff_t difference_type;
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typedef std::reverse_iterator<iterator> reverse_iterator;
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typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
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_Tp __elems_[_Size];
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// No explicit construct/copy/destroy for aggregate type
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_LIBCPP_INLINE_VISIBILITY void fill(const value_type& __u) {
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_VSTD::fill_n(__elems_, _Size, __u);
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}
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_LIBCPP_INLINE_VISIBILITY
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void swap(array& __a) _NOEXCEPT_(__is_nothrow_swappable<_Tp>::value) {
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std::swap_ranges(__elems_, __elems_ + _Size, __a.__elems_);
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}
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// iterators:
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
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iterator begin() _NOEXCEPT {return iterator(data());}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
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const_iterator begin() const _NOEXCEPT {return const_iterator(data());}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
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iterator end() _NOEXCEPT {return iterator(data() + _Size);}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
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const_iterator end() const _NOEXCEPT {return const_iterator(data() + _Size);}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
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reverse_iterator rbegin() _NOEXCEPT {return reverse_iterator(end());}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
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const_reverse_iterator rbegin() const _NOEXCEPT {return const_reverse_iterator(end());}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
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reverse_iterator rend() _NOEXCEPT {return reverse_iterator(begin());}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
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const_reverse_iterator rend() const _NOEXCEPT {return const_reverse_iterator(begin());}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
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const_iterator cbegin() const _NOEXCEPT {return begin();}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
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const_iterator cend() const _NOEXCEPT {return end();}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
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const_reverse_iterator crbegin() const _NOEXCEPT {return rbegin();}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
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const_reverse_iterator crend() const _NOEXCEPT {return rend();}
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// capacity:
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_LIBCPP_INLINE_VISIBILITY
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_LIBCPP_CONSTEXPR size_type size() const _NOEXCEPT {return _Size;}
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_LIBCPP_INLINE_VISIBILITY
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_LIBCPP_CONSTEXPR size_type max_size() const _NOEXCEPT {return _Size;}
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_LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
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_LIBCPP_CONSTEXPR bool empty() const _NOEXCEPT {return false; }
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// element access:
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
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reference operator[](size_type __n) {return __elems_[__n];}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
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const_reference operator[](size_type __n) const {return __elems_[__n];}
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_LIBCPP_CONSTEXPR_AFTER_CXX14 reference at(size_type __n);
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_LIBCPP_CONSTEXPR_AFTER_CXX11 const_reference at(size_type __n) const;
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 reference front() {return __elems_[0];}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 const_reference front() const {return __elems_[0];}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 reference back() {return __elems_[_Size - 1];}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 const_reference back() const {return __elems_[_Size - 1];}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
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value_type* data() _NOEXCEPT {return __elems_;}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
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const value_type* data() const _NOEXCEPT {return __elems_;}
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};
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template <class _Tp, size_t _Size>
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_LIBCPP_CONSTEXPR_AFTER_CXX14
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typename array<_Tp, _Size>::reference
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array<_Tp, _Size>::at(size_type __n)
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{
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if (__n >= _Size)
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__throw_out_of_range("array::at");
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return __elems_[__n];
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}
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template <class _Tp, size_t _Size>
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_LIBCPP_CONSTEXPR_AFTER_CXX11
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typename array<_Tp, _Size>::const_reference
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array<_Tp, _Size>::at(size_type __n) const
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{
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if (__n >= _Size)
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__throw_out_of_range("array::at");
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return __elems_[__n];
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}
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template <class _Tp>
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struct _LIBCPP_TEMPLATE_VIS array<_Tp, 0>
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{
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// types:
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typedef array __self;
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typedef _Tp value_type;
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typedef value_type& reference;
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typedef const value_type& const_reference;
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typedef value_type* iterator;
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typedef const value_type* const_iterator;
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typedef value_type* pointer;
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typedef const value_type* const_pointer;
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typedef size_t size_type;
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typedef ptrdiff_t difference_type;
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typedef std::reverse_iterator<iterator> reverse_iterator;
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typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
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typedef typename conditional<is_const<_Tp>::value, const char,
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char>::type _CharType;
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struct _ArrayInStructT { _Tp __data_[1]; };
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_ALIGNAS_TYPE(_ArrayInStructT) _CharType __elems_[sizeof(_ArrayInStructT)];
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// No explicit construct/copy/destroy for aggregate type
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_LIBCPP_INLINE_VISIBILITY void fill(const value_type&) {
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static_assert(!is_const<_Tp>::value,
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"cannot fill zero-sized array of type 'const T'");
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}
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_LIBCPP_INLINE_VISIBILITY
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void swap(array&) _NOEXCEPT {
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static_assert(!is_const<_Tp>::value,
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"cannot swap zero-sized array of type 'const T'");
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}
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// iterators:
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_LIBCPP_INLINE_VISIBILITY
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iterator begin() _NOEXCEPT {return iterator(data());}
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_LIBCPP_INLINE_VISIBILITY
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const_iterator begin() const _NOEXCEPT {return const_iterator(data());}
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_LIBCPP_INLINE_VISIBILITY
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iterator end() _NOEXCEPT {return iterator(data());}
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_LIBCPP_INLINE_VISIBILITY
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const_iterator end() const _NOEXCEPT {return const_iterator(data());}
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_LIBCPP_INLINE_VISIBILITY
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reverse_iterator rbegin() _NOEXCEPT {return reverse_iterator(end());}
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_LIBCPP_INLINE_VISIBILITY
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const_reverse_iterator rbegin() const _NOEXCEPT {return const_reverse_iterator(end());}
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_LIBCPP_INLINE_VISIBILITY
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reverse_iterator rend() _NOEXCEPT {return reverse_iterator(begin());}
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_LIBCPP_INLINE_VISIBILITY
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const_reverse_iterator rend() const _NOEXCEPT {return const_reverse_iterator(begin());}
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_LIBCPP_INLINE_VISIBILITY
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const_iterator cbegin() const _NOEXCEPT {return begin();}
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_LIBCPP_INLINE_VISIBILITY
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const_iterator cend() const _NOEXCEPT {return end();}
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_LIBCPP_INLINE_VISIBILITY
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const_reverse_iterator crbegin() const _NOEXCEPT {return rbegin();}
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_LIBCPP_INLINE_VISIBILITY
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const_reverse_iterator crend() const _NOEXCEPT {return rend();}
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// capacity:
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_LIBCPP_INLINE_VISIBILITY
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_LIBCPP_CONSTEXPR size_type size() const _NOEXCEPT {return 0; }
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_LIBCPP_INLINE_VISIBILITY
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_LIBCPP_CONSTEXPR size_type max_size() const _NOEXCEPT {return 0;}
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_LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
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_LIBCPP_CONSTEXPR bool empty() const _NOEXCEPT {return true;}
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// element access:
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_LIBCPP_INLINE_VISIBILITY
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reference operator[](size_type) {
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_LIBCPP_ASSERT(false, "cannot call array<T, 0>::operator[] on a zero-sized array");
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_LIBCPP_UNREACHABLE();
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}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
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const_reference operator[](size_type) const {
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_LIBCPP_ASSERT(false, "cannot call array<T, 0>::operator[] on a zero-sized array");
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_LIBCPP_UNREACHABLE();
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}
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_LIBCPP_INLINE_VISIBILITY
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reference at(size_type) {
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__throw_out_of_range("array<T, 0>::at");
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_LIBCPP_UNREACHABLE();
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}
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_LIBCPP_INLINE_VISIBILITY
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const_reference at(size_type) const {
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__throw_out_of_range("array<T, 0>::at");
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_LIBCPP_UNREACHABLE();
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}
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_LIBCPP_INLINE_VISIBILITY
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reference front() {
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_LIBCPP_ASSERT(false, "cannot call array<T, 0>::front() on a zero-sized array");
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_LIBCPP_UNREACHABLE();
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}
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_LIBCPP_INLINE_VISIBILITY
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const_reference front() const {
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_LIBCPP_ASSERT(false, "cannot call array<T, 0>::front() on a zero-sized array");
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_LIBCPP_UNREACHABLE();
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}
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_LIBCPP_INLINE_VISIBILITY
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reference back() {
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_LIBCPP_ASSERT(false, "cannot call array<T, 0>::back() on a zero-sized array");
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_LIBCPP_UNREACHABLE();
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}
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_LIBCPP_INLINE_VISIBILITY
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const_reference back() const {
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_LIBCPP_ASSERT(false, "cannot call array<T, 0>::back() on a zero-sized array");
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_LIBCPP_UNREACHABLE();
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}
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_LIBCPP_INLINE_VISIBILITY
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value_type* data() _NOEXCEPT {return reinterpret_cast<value_type*>(__elems_);}
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_LIBCPP_INLINE_VISIBILITY
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const value_type* data() const _NOEXCEPT {return reinterpret_cast<const value_type*>(__elems_);}
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};
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#ifndef _LIBCPP_HAS_NO_DEDUCTION_GUIDES
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template<class _Tp, class... _Args,
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class = typename enable_if<(is_same_v<_Tp, _Args> && ...), void>::type
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>
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array(_Tp, _Args...)
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-> array<_Tp, 1 + sizeof...(_Args)>;
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#endif
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template <class _Tp, size_t _Size>
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inline _LIBCPP_INLINE_VISIBILITY
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_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
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operator==(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
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{
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return _VSTD::equal(__x.begin(), __x.end(), __y.begin());
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}
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template <class _Tp, size_t _Size>
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inline _LIBCPP_INLINE_VISIBILITY
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_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
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operator!=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
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{
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return !(__x == __y);
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}
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template <class _Tp, size_t _Size>
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inline _LIBCPP_INLINE_VISIBILITY
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_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
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operator<(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
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{
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return _VSTD::lexicographical_compare(__x.begin(), __x.end(),
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__y.begin(), __y.end());
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}
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template <class _Tp, size_t _Size>
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inline _LIBCPP_INLINE_VISIBILITY
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_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
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operator>(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
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{
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return __y < __x;
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}
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template <class _Tp, size_t _Size>
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inline _LIBCPP_INLINE_VISIBILITY
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_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
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operator<=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
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{
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return !(__y < __x);
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}
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template <class _Tp, size_t _Size>
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inline _LIBCPP_INLINE_VISIBILITY
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_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
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operator>=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
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{
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return !(__x < __y);
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}
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template <class _Tp, size_t _Size>
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inline _LIBCPP_INLINE_VISIBILITY
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typename enable_if
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<
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_Size == 0 ||
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__is_swappable<_Tp>::value,
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void
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>::type
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swap(array<_Tp, _Size>& __x, array<_Tp, _Size>& __y)
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_NOEXCEPT_(noexcept(__x.swap(__y)))
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{
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__x.swap(__y);
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}
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template <class _Tp, size_t _Size>
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struct _LIBCPP_TEMPLATE_VIS tuple_size<array<_Tp, _Size> >
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: public integral_constant<size_t, _Size> {};
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template <size_t _Ip, class _Tp, size_t _Size>
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class _LIBCPP_TEMPLATE_VIS tuple_element<_Ip, array<_Tp, _Size> >
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{
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static_assert(_Ip < _Size, "Index out of bounds in std::tuple_element<> (std::array)");
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public:
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typedef _Tp type;
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};
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template <size_t _Ip, class _Tp, size_t _Size>
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inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
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_Tp&
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get(array<_Tp, _Size>& __a) _NOEXCEPT
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{
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static_assert(_Ip < _Size, "Index out of bounds in std::get<> (std::array)");
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return __a.__elems_[_Ip];
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}
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template <size_t _Ip, class _Tp, size_t _Size>
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inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
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const _Tp&
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get(const array<_Tp, _Size>& __a) _NOEXCEPT
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{
|
|
static_assert(_Ip < _Size, "Index out of bounds in std::get<> (const std::array)");
|
|
return __a.__elems_[_Ip];
|
|
}
|
|
|
|
#ifndef _LIBCPP_CXX03_LANG
|
|
|
|
template <size_t _Ip, class _Tp, size_t _Size>
|
|
inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
|
|
_Tp&&
|
|
get(array<_Tp, _Size>&& __a) _NOEXCEPT
|
|
{
|
|
static_assert(_Ip < _Size, "Index out of bounds in std::get<> (std::array &&)");
|
|
return _VSTD::move(__a.__elems_[_Ip]);
|
|
}
|
|
|
|
template <size_t _Ip, class _Tp, size_t _Size>
|
|
inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
|
|
const _Tp&&
|
|
get(const array<_Tp, _Size>&& __a) _NOEXCEPT
|
|
{
|
|
static_assert(_Ip < _Size, "Index out of bounds in std::get<> (const std::array &&)");
|
|
return _VSTD::move(__a.__elems_[_Ip]);
|
|
}
|
|
|
|
#endif // !_LIBCPP_CXX03_LANG
|
|
|
|
_LIBCPP_END_NAMESPACE_STD
|
|
|
|
#endif // _LIBCPP_ARRAY
|