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lnav/src/ring_span.hh

947 lines
23 KiB
C++

//
// Copyright (c) 2015 Arthur O'Dwyer
// Copyright 2017-2018 by Martin Moene
//
// https://github.com/martinmoene/ring-span-lite
//
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
#pragma once
#ifndef NONSTD_RING_SPAN_LITE_HPP
# define NONSTD_RING_SPAN_LITE_HPP
# define ring_span_lite_MAJOR 0
# define ring_span_lite_MINOR 2
# define ring_span_lite_PATCH 0
# define ring_span_lite_VERSION \
nsrs_STRINGIFY(ring_span_lite_MAJOR) "." nsrs_STRINGIFY( \
ring_span_lite_MINOR) "." nsrs_STRINGIFY(ring_span_lite_PATCH)
# define nsrs_STRINGIFY(x) nsrs_STRINGIFY_(x)
# define nsrs_STRINGIFY_(x) # x
// ring-span-lite configuration:
# define nsrs_RING_SPAN_DEFAULT 0
# define nsrs_RING_SPAN_NONSTD 1
# define nsrs_RING_SPAN_STD 2
# if !defined(nsrs_CONFIG_SELECT_RING_SPAN)
# define nsrs_CONFIG_SELECT_RING_SPAN \
(nsrs_HAVE_STD_RING_SPAN ? nsrs_RING_SPAN_STD \
: nsrs_RING_SPAN_NONSTD)
# endif
# ifndef nsrs_CONFIG_STRICT_P0059
# define nsrs_CONFIG_STRICT_P0059 0
# endif
# define nsrs_RING_SPAN_LITE_EXTENSION (!nsrs_CONFIG_STRICT_P0059)
# ifndef nsrs_CONFIG_CONFIRMS_COMPILATION_ERRORS
# define nsrs_CONFIG_CONFIRMS_COMPILATION_ERRORS 0
# endif
// C++ language version detection (C++20 is speculative):
// Note: VC14.0/1900 (VS2015) lacks too much from C++14.
# ifndef nsrs_CPLUSPLUS
# if defined(_MSVC_LANG) && !defined(__clang__)
# define nsrs_CPLUSPLUS (_MSC_VER == 1900 ? 201103L : _MSVC_LANG)
# else
# define nsrs_CPLUSPLUS __cplusplus
# endif
# endif
# define nsrs_CPP98_OR_GREATER (nsrs_CPLUSPLUS >= 199711L)
# define nsrs_CPP11_OR_GREATER (nsrs_CPLUSPLUS >= 201103L)
# define nsrs_CPP11_OR_GREATER_ (nsrs_CPLUSPLUS >= 201103L)
# define nsrs_CPP14_OR_GREATER (nsrs_CPLUSPLUS >= 201402L)
# define nsrs_CPP17_OR_GREATER (nsrs_CPLUSPLUS >= 201703L)
# define nsrs_CPP20_OR_GREATER (nsrs_CPLUSPLUS >= 202000L)
// Use C++XX std::ring_span if available and requested:
# define nsrs_HAVE_STD_RING_SPAN 0
//#if nsrs_CPP17_OR_GREATER && defined(__has_include )
//# if __has_include( <any> )
//# define nsrs_HAVE_STD_RING_SPAN 1
//# else
//# define nsrs_HAVE_STD_RING_SPAN 0
//# endif
//#else
//# define nsrs_HAVE_STD_RING_SPAN 0
//#endif
# define nsrs_USES_STD_RING_SPAN \
((nsrs_CONFIG_SELECT_RING_SPAN == nsrs_RING_SPAN_STD) \
|| ((nsrs_CONFIG_SELECT_RING_SPAN == nsrs_RING_SPAN_DEFAULT) \
&& nsrs_HAVE_STD_RING_SPAN))
// Compiler versions:
//
// MSVC++ 6.0 _MSC_VER == 1200 (Visual Studio 6.0)
// MSVC++ 7.0 _MSC_VER == 1300 (Visual Studio .NET 2002)
// MSVC++ 7.1 _MSC_VER == 1310 (Visual Studio .NET 2003)
// MSVC++ 8.0 _MSC_VER == 1400 (Visual Studio 2005)
// MSVC++ 9.0 _MSC_VER == 1500 (Visual Studio 2008)
// MSVC++ 10.0 _MSC_VER == 1600 (Visual Studio 2010)
// MSVC++ 11.0 _MSC_VER == 1700 (Visual Studio 2012)
// MSVC++ 12.0 _MSC_VER == 1800 (Visual Studio 2013)
// MSVC++ 14.0 _MSC_VER == 1900 (Visual Studio 2015)
// ............_MSVC_LANG: 201402 for -std:c++14, default
// MSVC++ 14.1 _MSC_VER >= 1910 (Visual Studio 2017)
// ............_MSVC_LANG: 201402 for -std:c++14, default
// ............_MSVC_LANG: 201703 for -std:c++17
# if defined(_MSC_VER) && !defined(__clang__)
# define nsrs_COMPILER_MSVC_VER (_MSC_VER)
# define nsrs_COMPILER_MSVC_VERSION \
(_MSC_VER / 10 - 10 * (5 + (_MSC_VER < 1900)))
# else
# define nsrs_COMPILER_MSVC_VER 0
# define nsrs_COMPILER_MSVC_VERSION 0
# endif
# define nsrs_COMPILER_VERSION(major, minor, patch) \
(10 * (10 * major + minor) + patch)
# if defined(__clang__)
# define nsrs_COMPILER_CLANG_VERSION \
nsrs_COMPILER_VERSION( \
__clang_major__, __clang_minor__, __clang_patchlevel__)
# else
# define nsrs_COMPILER_CLANG_VERSION 0
# endif
# if defined(__GNUC__) && !defined(__clang__)
# define nsrs_COMPILER_GNUC_VERSION \
nsrs_COMPILER_VERSION(__GNUC__, __GNUC_MINOR__, __GNUC_PATCHLEVEL__)
# else
# define nsrs_COMPILER_GNUC_VERSION 0
# endif
// half-open range [lo..hi):
//#define nsrs_BETWEEN( v, lo, hi ) ( (lo) <= (v) && (v) < (hi) )
// Presence of language and library features:
# ifdef _HAS_CPP0X
# define nsrs_HAS_CPP0X _HAS_CPP0X
# else
# define nsrs_HAS_CPP0X 0
# endif
// Unless defined otherwise below, consider VC14 as C++11 for ring-span-lite:
# if nsrs_COMPILER_MSVC_VER >= 1900
# undef nsrs_CPP11_OR_GREATER
# define nsrs_CPP11_OR_GREATER 1
# endif
# define nsrs_CPP11_90 \
(nsrs_CPP11_OR_GREATER_ || nsrs_COMPILER_MSVC_VER >= 1500)
# define nsrs_CPP11_100 \
(nsrs_CPP11_OR_GREATER_ || nsrs_COMPILER_MSVC_VER >= 1600)
# define nsrs_CPP11_110 \
(nsrs_CPP11_OR_GREATER_ || nsrs_COMPILER_MSVC_VER >= 1700)
# define nsrs_CPP11_120 \
(nsrs_CPP11_OR_GREATER_ || nsrs_COMPILER_MSVC_VER >= 1800)
# define nsrs_CPP11_140 \
(nsrs_CPP11_OR_GREATER_ || nsrs_COMPILER_MSVC_VER >= 1900)
# define nsrs_CPP14_000 (nsrs_CPP14_OR_GREATER)
# define nsrs_CPP17_000 (nsrs_CPP17_OR_GREATER)
// Presence of C++11 language features:
// half-open range [lo..hi):
# define nsrs_BETWEEN(v, lo, hi) ((lo) <= (v) && (v) < (hi))
// Presence of C++11 language features:
# define nsrs_HAVE_CONSTEXPR_11 nsrs_CPP11_140
# define nsrs_HAVE_IS_DEFAULT nsrs_CPP11_140
# define nsrs_HAVE_IS_DELETE nsrs_CPP11_140
# define nsrs_HAVE_NOEXCEPT nsrs_CPP11_140
# define nsrs_HAVE_NULLPTR nsrs_CPP11_100
// Presence of C++14 language features:
# define nsrs_HAVE_CONSTEXPR_14 nsrs_CPP14_000
// Presence of C++17 language features:
// no tag
// Presence of C++ library features:
// no tag
// Compiler warning suppression:
# if defined(__clang__)
# pragma clang diagnostic push
# pragma clang diagnostic ignored "-Wundef"
# define nsrs_RESTORE_WARNINGS() _Pragma("clang diagnostic pop")
# elif defined __GNUC__
# pragma GCC diagnostic push
# pragma GCC diagnostic ignored "-Wundef"
# define nsrs_RESTORE_WARNINGS() _Pragma("GCC diagnostic pop")
# elif nsrs_COMPILER_MSVC_VERSION >= 140
# define nsrs_DISABLE_MSVC_WARNINGS(codes) \
__pragma(warning(push)) __pragma(warning(disable : codes))
# define nsrs_RESTORE_WARNINGS() __pragma(warning(pop))
// Suppress the following MSVC warnings:
// - C4345: initialization behavior changed
//
// Suppress the following MSVC GSL warnings:
// - C26439, gsl::f.6 : special function 'function' can be declared 'noexcept'
// - C26440, gsl::f.6 : function 'function' can be declared 'noexcept'
// - C26472, gsl::t.1 : don't use a static_cast for arithmetic conversions;
// use brace initialization, gsl::narrow_cast or
// gsl::narrow
// - C26473: gsl::t.1 : don't cast between pointer types where the source type
// and the target type are the same
// - C26481: gsl::b.1 : don't use pointer arithmetic. Use span instead
// - C26490: gsl::t.1 : don't use reinterpret_cast
nsrs_DISABLE_MSVC_WARNINGS(4345 26439 26440 26472 26473 26481 26490)
# else
# define nsrs_RESTORE_WARNINGS() /*empty*/
# endif
// C++ feature usage:
# if nsrs_HAVE_CONSTEXPR_11
# define nsrs_constexpr constexpr
# else
# define nsrs_constexpr /*constexpr*/
# endif
# if nsrs_HAVE_CONSTEXPR_14
# define nsrs_constexpr14 constexpr
# else
# define nsrs_constexpr14 /*constexpr*/
# endif
# if nsrs_HAVE_NOEXCEPT
# define nsrs_noexcept noexcept
# define nsrs_noexcept_op noexcept
# else
# define nsrs_noexcept /*noexcept*/
# define nsrs_noexcept_op(expr) /*noexcept(expr)*/
# endif
# if nsrs_HAVE_NULLPTR
# define nsrs_nullptr nullptr
# else
# define nsrs_nullptr NULL
# endif
// includes:
# include <cassert>
# include <iterator>
# include <utility>
// additional includes:
# if !nsrs_CPP11_OR_GREATER
# include <algorithm> // std::swap() until C++11
# endif
namespace nonstd {
# if nsrs_CPP11_OR_GREATER
using std::move;
# else
template<typename T>
T const&
move(T const& t)
{
return t;
}
# endif
template<bool B, class T, class F>
struct conditional {
typedef T type;
};
template<class T, class F>
struct conditional<false, T, F> {
typedef F type;
};
# if nsrs_CPP11_OR_GREATER
template<bool B, class T, class F>
using conditional_t = typename conditional<B, T, F>::type;
template<bool B, class T = void>
using enable_if_t = typename std::enable_if<B, T>::type;
# endif
//
// element extraction policies:
//
template<class T>
struct null_popper {
typedef void return_type;
void operator()(T&) const nsrs_noexcept {}
};
template<class T>
struct default_popper {
typedef T return_type;
T operator()(T& t) const
{
return nonstd::move(t);
}
};
template<class T>
struct copy_popper {
typedef T return_type;
# if nsrs_RING_SPAN_LITE_EXTENSION
# if nsrs_CPP11_OR_GREATER
copy_popper(T t) : m_copy(std::move(t)) {}
# else
copy_popper(T const& t) : m_copy(t) {}
# endif
# else
copy_popper(T&& t) : copy(std::move(t)) {}
# endif
T operator()(T& t) const
{
using std::swap;
T result(m_copy);
swap(t, result);
return result;
}
T m_copy;
};
// forward-declare iterator:
namespace ring_detail {
template<class, bool>
class ring_iterator;
}
//
// ring span:
//
template<class T, class Popper = default_popper<T> >
class ring_span {
public:
typedef T value_type;
typedef T* pointer;
typedef T& reference;
typedef T const& const_reference;
typedef std::size_t size_type;
typedef ring_span<T, Popper> type;
typedef ring_detail::ring_iterator<type, false> iterator;
typedef ring_detail::ring_iterator<type, true> const_iterator;
# if nsrs_RING_SPAN_LITE_EXTENSION
typedef std::reverse_iterator<iterator> reverse_iterator;
typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
# endif
// construction:
template<class ContiguousIterator>
ring_span(ContiguousIterator begin,
ContiguousIterator end,
Popper popper = Popper()) nsrs_noexcept
: m_data(&*begin)
, m_size(0)
, m_capacity(static_cast<size_type>(end - begin))
, m_front_idx(0)
, m_popper(nonstd::move(popper))
{
}
template<class ContiguousIterator>
ring_span(ContiguousIterator begin,
ContiguousIterator end,
ContiguousIterator first,
size_type size,
Popper popper = Popper()) nsrs_noexcept
: m_data(&*begin)
, m_size(size)
, m_capacity(static_cast<size_type>(end - begin))
, m_front_idx(static_cast<size_type>(first - begin))
, m_popper(nonstd::move(popper))
{
}
# if nsrs_HAVE_IS_DEFAULT
ring_span(ring_span&&) = default;
ring_span& operator=(ring_span&&) = default;
# else
private:
ring_span(ring_span const&);
ring_span& operator=(ring_span const&);
public:
# endif
// observers:
bool empty() const nsrs_noexcept
{
return m_size == 0;
}
bool full() const nsrs_noexcept
{
return m_size == m_capacity;
}
size_type size() const nsrs_noexcept
{
return m_size;
}
size_type capacity() const nsrs_noexcept
{
return m_capacity;
}
// element access:
reference front() nsrs_noexcept
{
return *begin();
}
const_reference front() const nsrs_noexcept
{
return *begin();
}
reference back() nsrs_noexcept
{
return *(--end());
}
const_reference back() const nsrs_noexcept
{
return *(--end());
}
// iteration:
iterator begin() nsrs_noexcept
{
return iterator(0, this);
}
const_iterator begin() const nsrs_noexcept
{
return cbegin();
}
const_iterator cbegin() const nsrs_noexcept
{
return const_iterator(0, this);
}
iterator end() nsrs_noexcept
{
return iterator(size(), this);
}
const_iterator end() const nsrs_noexcept
{
return cend();
}
const_iterator cend() const nsrs_noexcept
{
return const_iterator(size(), this);
}
# if nsrs_RING_SPAN_LITE_EXTENSION
reverse_iterator rbegin() nsrs_noexcept
{
return reverse_iterator(end());
}
reverse_iterator rend() nsrs_noexcept
{
return reverse_iterator(begin());
}
const_reverse_iterator rbegin() const nsrs_noexcept
{
return crbegin();
}
const_reverse_iterator rend() const nsrs_noexcept
{
return crend();
}
const_reverse_iterator crbegin() const nsrs_noexcept
{
return const_reverse_iterator(cend());
}
const_reverse_iterator crend() const nsrs_noexcept
{
return const_reverse_iterator(cbegin());
}
# endif
void erase_from(iterator first)
{
m_size = static_cast<size_type>(std::distance(begin(), first));
}
// element insertion, extraction:
typename Popper::return_type pop_front()
{
assert(!empty());
reference element = front_();
increment_front_();
return m_popper(element);
}
# if nsrs_RING_SPAN_LITE_EXTENSION
typename Popper::return_type pop_back()
{
assert(!empty());
reference element = back_();
decrement_back_();
return m_popper(element);
}
# endif
# if nsrs_CPP11_OR_GREATER
template<bool b = true,
typename
= nonstd::enable_if_t<b && std::is_copy_assignable<T>::value> >
void push_back(value_type const& value)
nsrs_noexcept_op((std::is_nothrow_copy_assignable<T>::value))
# else
void push_back(value_type const& value)
# endif
{
if (full())
increment_front_and_back_();
else
increment_back_();
back_() = value;
}
# if nsrs_CPP11_OR_GREATER
template<bool b = true,
typename
= nonstd::enable_if_t<b && std::is_move_assignable<T>::value> >
void push_back(value_type&& value)
nsrs_noexcept_op((std::is_nothrow_move_assignable<T>::value))
{
if (full())
increment_front_and_back_();
else
increment_back_();
back_() = std::move(value);
}
template<class... Args>
void emplace_back(Args&&... args)
nsrs_noexcept_op((std::is_nothrow_constructible<T, Args...>::value
&& std::is_nothrow_move_assignable<T>::value))
{
if (full())
increment_front_and_back_();
else
increment_back_();
back_() = T(std::forward<Args>(args)...);
}
# endif
# if nsrs_RING_SPAN_LITE_EXTENSION
# if nsrs_CPP11_OR_GREATER
template<bool b = true,
typename
= nonstd::enable_if_t<b && std::is_copy_assignable<T>::value> >
void push_front(T const& value)
nsrs_noexcept_op((std::is_nothrow_copy_assignable<T>::value))
# else
void push_front(T const& value)
# endif
{
if (full())
decrement_front_and_back_();
else
decrement_front_();
front_() = value;
}
# if nsrs_CPP11_OR_GREATER
template<bool b = true,
typename
= nonstd::enable_if_t<b && std::is_move_assignable<T>::value> >
void push_front(T&& value)
nsrs_noexcept_op((std::is_nothrow_move_assignable<T>::value))
{
if (full())
decrement_front_and_back_();
else
decrement_front_();
front_() = std::move(value);
}
template<typename... Args>
void emplace_front(Args&&... args)
nsrs_noexcept_op((std::is_nothrow_constructible<T, Args...>::value
&& std::is_nothrow_move_assignable<T>::value))
{
if (full())
decrement_front_and_back_();
else
decrement_front_();
front_() = T(std::forward<Args>(args)...);
}
# endif
# endif // nsrs_RING_SPAN_LITE_EXTENSION
// swap:
void swap(type& rhs)
nsrs_noexcept // nsrs_noexcept_op(std::is_nothrow_swappable<Popper>::value);
{
using std::swap;
swap(m_data, rhs.m_data);
swap(m_size, rhs.m_size);
swap(m_capacity, rhs.m_capacity);
swap(m_front_idx, rhs.m_front_idx);
swap(m_popper, rhs.m_popper);
}
private:
friend class ring_detail::ring_iterator<ring_span,
true>; // const_iterator;
friend class ring_detail::ring_iterator<ring_span, false>; // iterator;
size_type normalize_(size_type const idx) const nsrs_noexcept
{
return idx % m_capacity;
}
reference at(size_type idx) nsrs_noexcept
{
return m_data[normalize_(m_front_idx + idx)];
}
const_reference at(size_type idx) const nsrs_noexcept
{
return m_data[normalize_(m_front_idx + idx)];
}
reference front_() nsrs_noexcept
{
return *(m_data + m_front_idx);
}
const_reference front_() const nsrs_noexcept
{
return *(m_data + m_front_idx);
}
reference back_() nsrs_noexcept
{
return *(m_data + normalize_(m_front_idx + m_size - 1));
}
const_reference back_() const nsrs_noexcept
{
return *(m_data + normalize_(m_front_idx + m_size - 1));
}
void increment_front_() nsrs_noexcept
{
m_front_idx = normalize_(m_front_idx + 1);
--m_size;
}
void decrement_front_() nsrs_noexcept
{
m_front_idx = normalize_(m_front_idx + m_capacity - 1);
++m_size;
}
void increment_back_() nsrs_noexcept
{
++m_size;
}
void decrement_back_() nsrs_noexcept
{
--m_size;
}
void increment_front_and_back_() nsrs_noexcept
{
m_front_idx = normalize_(m_front_idx + 1);
}
void decrement_front_and_back_() nsrs_noexcept
{
m_front_idx = normalize_(m_front_idx + m_capacity - 1);
}
private:
pointer m_data;
size_type m_size;
size_type m_capacity;
size_type m_front_idx;
Popper m_popper;
};
// swap:
template<class T, class Popper>
inline void
swap(ring_span<T, Popper>& lhs, ring_span<T, Popper>& rhs)
nsrs_noexcept_op(nsrs_noexcept_op(lhs.swap(rhs)))
{
lhs.swap(rhs);
}
namespace ring_detail {
//
// ring iterator:
//
# if 0
template< class RS, bool is_const >
class ring_iterator : public std::iterator
<
std::random_access_iterator_tag
, typename nonstd::conditional<is_const, const typename RS::value_type, typename RS::value_type>::type
>
# endif
template<class RS, bool is_const>
class ring_iterator {
public:
typedef ring_iterator<RS, is_const> type;
typedef std::ptrdiff_t difference_type;
typedef typename RS::value_type value_type;
typedef typename nonstd::
conditional<is_const, const value_type, value_type>::type* pointer;
typedef typename nonstd::
conditional<is_const, const value_type, value_type>::type& reference;
typedef std::random_access_iterator_tag iterator_category;
# if nsrs_CPP11_OR_GREATER
ring_iterator() = default;
# else
ring_iterator() : m_idx(), m_rs() {}
# endif
# if nsrs_RING_SPAN_LITE_EXTENSION
// conversion to const iterator:
operator ring_iterator<RS, true>() const nsrs_noexcept
{
return ring_iterator<RS, true>(m_idx, m_rs);
}
# endif
// access content:
reference operator*() const nsrs_noexcept
{
return m_rs->at(m_idx);
}
// advance iterator:
type& operator++() nsrs_noexcept
{
++m_idx;
return *this;
}
type operator++(int) nsrs_noexcept
{
type r(*this);
++*this;
return r;
}
type& operator--() nsrs_noexcept
{
--m_idx;
return *this;
}
type operator--(int) nsrs_noexcept
{
type r(*this);
--*this;
return r;
}
# if defined(__clang__) || defined(__GNUC__)
# pragma GCC diagnostic push
# pragma GCC diagnostic ignored "-Wsign-conversion"
# endif
type& operator+=(int i) nsrs_noexcept
{
m_idx += i;
return *this;
}
type& operator-=(int i) nsrs_noexcept
{
m_idx -= i;
return *this;
}
# if defined(__clang__) || defined(__GNUC__)
# pragma GCC diagnostic pop
# endif
# if nsrs_RING_SPAN_LITE_EXTENSION
template<bool C>
difference_type operator-(ring_iterator<RS, C> const& rhs) const
nsrs_noexcept
{
return static_cast<difference_type>(this->m_idx)
- static_cast<difference_type>(rhs.m_idx);
}
# endif
// comparison:
template<bool C>
bool operator<(ring_iterator<RS, C> const& rhs) const nsrs_noexcept
{
assert(this->m_rs == rhs.m_rs);
return (this->m_idx < rhs.m_idx);
}
template<bool C>
bool operator==(ring_iterator<RS, C> const& rhs) const nsrs_noexcept
{
assert(this->m_rs == rhs.m_rs);
return (this->m_idx == rhs.m_idx);
}
// other comparisons expressed in <, ==:
template<bool C>
inline bool operator!=(ring_iterator<RS, C> const& rhs) const nsrs_noexcept
{
return !(*this == rhs);
}
template<bool C>
inline bool operator<=(ring_iterator<RS, C> const& rhs) const nsrs_noexcept
{
return !(rhs < *this);
}
template<bool C>
inline bool operator>(ring_iterator<RS, C> const& rhs) const nsrs_noexcept
{
return rhs < *this;
}
template<bool C>
inline bool operator>=(ring_iterator<RS, C> const& rhs) const nsrs_noexcept
{
return !(*this < rhs);
}
private:
friend RS; // clang: non-class friend type 'RS' is a C++11 extension
// [-Wc++11-extensions]
friend class ring_iterator<RS, !is_const>;
typedef typename RS::size_type size_type;
typedef
typename nonstd::conditional<is_const, const RS, RS>::type ring_type;
ring_iterator(size_type idx,
typename nonstd::conditional<is_const, const RS, RS>::type*
rs) nsrs_noexcept
: m_idx(idx)
, m_rs(rs)
{
}
private:
size_type m_idx;
ring_type* m_rs;
};
// advanced iterator:
template<class RS, bool C>
inline ring_iterator<RS, C>
operator+(ring_iterator<RS, C> it, int i) nsrs_noexcept
{
it += i;
return it;
}
template<class RS, bool C>
inline ring_iterator<RS, C>
operator-(ring_iterator<RS, C> it, int i) nsrs_noexcept
{
it -= i;
return it;
}
} // namespace ring_detail
} // namespace nonstd
nsrs_RESTORE_WARNINGS()
#endif // NONSTD_RING_SPAN_LITE_HPP