[libcxx-commits] [libcxx] [libc++] Implement P0429R9 `std::flat_map` (PR #98643)
Louis Dionne via libcxx-commits
libcxx-commits at lists.llvm.org
Fri Sep 13 11:35:58 PDT 2024
================
@@ -0,0 +1,1332 @@
+// -*- 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___FLAT_MAP_FLAT_MAP_H
+#define _LIBCPP___FLAT_MAP_FLAT_MAP_H
+
+#include <__algorithm/lexicographical_compare_three_way.h>
+#include <__algorithm/ranges_adjacent_find.h>
+#include <__algorithm/ranges_equal.h>
+#include <__algorithm/ranges_inplace_merge.h>
+#include <__algorithm/ranges_lower_bound.h>
+#include <__algorithm/ranges_partition_point.h>
+#include <__algorithm/ranges_stable_sort.h>
+#include <__algorithm/ranges_unique.h>
+#include <__algorithm/ranges_upper_bound.h>
+#include <__compare/synth_three_way.h>
+#include <__concepts/convertible_to.h>
+#include <__config>
+#include <__flat_map/container_traits.h>
+#include <__flat_map/sorted_unique.h>
+#include <__functional/invoke.h>
+#include <__functional/is_transparent.h>
+#include <__functional/operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/distance.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/ranges_iterator_traits.h>
+#include <__iterator/reverse_iterator.h>
+#include <__memory/allocator_traits.h>
+#include <__memory/uses_allocator.h>
+#include <__memory/uses_allocator_construction.h>
+#include <__ranges/concepts.h>
+#include <__ranges/container_compatible_range.h>
+#include <__ranges/drop_view.h>
+#include <__ranges/ref_view.h>
+#include <__ranges/subrange.h>
+#include <__ranges/zip_view.h>
+#include <__type_traits/conjunction.h>
+#include <__type_traits/invoke.h>
+#include <__type_traits/is_allocator.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/maybe_const.h>
+#include <__utility/pair.h>
+#include <initializer_list>
+#include <stdexcept>
+#include <string>
+#include <vector>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Key,
+ class _Tp,
+ class _Compare = less<_Key>,
+ class _KeyContainer = vector<_Key>,
+ class _MappedContainer = vector<_Tp>>
+class flat_map {
+ template <bool _Const>
+ struct __iterator;
+
+ template <class, class, class, class, class>
+ friend class flat_map;
+
+public:
+ // types
+ using key_type = _Key;
+ using mapped_type = _Tp;
+ using value_type = pair<key_type, mapped_type>;
+ using key_compare = _Compare;
+ // TODO : the following is the spec, but not implementable for vector<bool>
+ // using reference = pair<const key_type&, mapped_type&>;
+ // using const_reference = pair<const key_type&, const mapped_type&>;
+ using reference = pair<ranges::range_reference_t<const _KeyContainer>, ranges::range_reference_t<_MappedContainer>>;
+ using const_reference =
+ pair<ranges::range_reference_t<const _KeyContainer>, ranges::range_reference_t<const _MappedContainer>>;
+ using size_type = size_t;
+ using difference_type = ptrdiff_t;
+ using iterator = __iterator<false>; // see [container.requirements]
+ using const_iterator = __iterator<true>; // see [container.requirements]
+ using reverse_iterator = std::reverse_iterator<iterator>;
+ using const_reverse_iterator = std::reverse_iterator<const_iterator>;
+ using key_container_type = _KeyContainer;
+ using mapped_container_type = _MappedContainer;
+
+ class value_compare {
+ private:
+ key_compare __comp_;
+ value_compare(key_compare __c) : __comp_(__c) {}
+ friend flat_map;
+
+ public:
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const_reference __x, const_reference __y) const {
+ return __comp_(__x.first, __y.first);
+ }
+ };
+
+ struct containers {
+ key_container_type keys;
+ mapped_container_type values;
+ };
+
+private:
+ template <class _Allocator>
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool __allocator_ctor_constraint =
+ _And<uses_allocator<key_container_type, _Allocator>, uses_allocator<mapped_container_type, _Allocator>>::value;
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool __is_compare_transparent = __is_transparent_v<_Compare, _Compare>;
+
+ template <bool _Const>
+ struct __iterator {
+ private:
+ using __key_iterator = ranges::iterator_t<const key_container_type>;
+ using __mapped_iterator = ranges::iterator_t<__maybe_const<_Const, mapped_container_type>>;
+ using __reference = pair<iter_reference_t<__key_iterator>, iter_reference_t<__mapped_iterator>>;
+
+ struct __arrow_proxy {
+ __reference __ref_;
+ _LIBCPP_HIDE_FROM_ABI __reference* operator->() { return std::addressof(__ref_); }
+ };
+
+ __key_iterator __key_iter_;
+ __mapped_iterator __mapped_iter_;
+
+ friend flat_map;
+
+ public:
+ using iterator_concept = random_access_iterator_tag;
+ using iterator_category = input_iterator_tag;
+ using value_type = flat_map::value_type;
+ using difference_type = flat_map::difference_type;
+
+ _LIBCPP_HIDE_FROM_ABI __iterator() = default;
+
+ _LIBCPP_HIDE_FROM_ABI __iterator(__iterator<!_Const> __i)
+ requires _Const && convertible_to<ranges::iterator_t<key_container_type>, __key_iterator> &&
+ convertible_to<ranges::iterator_t<mapped_container_type>, __mapped_iterator>
+ : __key_iter_(std::move(__i.__key_iter_)), __mapped_iter_(std::move(__i.__mapped_iter_)) {}
+
+ _LIBCPP_HIDE_FROM_ABI __iterator(__key_iterator __key_iter, __mapped_iterator __mapped_iter)
+ : __key_iter_(std::move(__key_iter)), __mapped_iter_(std::move(__mapped_iter)) {}
+
+ _LIBCPP_HIDE_FROM_ABI __reference operator*() const { return __reference(*__key_iter_, *__mapped_iter_); }
+ _LIBCPP_HIDE_FROM_ABI __arrow_proxy operator->() const { return __arrow_proxy(**this); }
+
+ _LIBCPP_HIDE_FROM_ABI __iterator& operator++() {
+ ++__key_iter_;
+ ++__mapped_iter_;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __iterator operator++(int) {
+ __iterator __tmp(*this);
+ ++*this;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __iterator& operator--() {
+ --__key_iter_;
+ --__mapped_iter_;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __iterator operator--(int) {
+ __iterator __tmp(*this);
+ --*this;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __iterator& operator+=(difference_type __x) {
+ __key_iter_ += __x;
+ __mapped_iter_ += __x;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __iterator& operator-=(difference_type __x) {
+ __key_iter_ -= __x;
+ __mapped_iter_ -= __x;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __reference operator[](difference_type __n) const { return *(*this + __n); }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __iterator& __x, const __iterator& __y) {
+ return __x.__key_iter_ == __y.__key_iter_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend bool operator<(const __iterator& __x, const __iterator& __y) {
+ return __x.__key_iter_ < __y.__key_iter_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend bool operator>(const __iterator& __x, const __iterator& __y) { return __y < __x; }
+
+ _LIBCPP_HIDE_FROM_ABI friend bool operator<=(const __iterator& __x, const __iterator& __y) { return !(__y < __x); }
+
+ _LIBCPP_HIDE_FROM_ABI friend bool operator>=(const __iterator& __x, const __iterator& __y) { return !(__x < __y); }
+
+ _LIBCPP_HIDE_FROM_ABI friend auto operator<=>(const __iterator& __x, const __iterator& __y)
+ requires three_way_comparable<__key_iterator>
+ {
+ return __x.__key_iter_ <=> __y.__key_iter_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend __iterator operator+(const __iterator& __i, difference_type __n) {
+ auto __tmp = __i;
+ __tmp += __n;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend __iterator operator+(difference_type __n, const __iterator& __i) { return __i + __n; }
+
+ _LIBCPP_HIDE_FROM_ABI friend __iterator operator-(const __iterator& __i, difference_type __n) {
+ auto __tmp = __i;
+ __tmp -= __n;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend difference_type operator-(const __iterator& __x, const __iterator& __y) {
+ return difference_type(__x.__key_iter_ - __y.__key_iter_);
+ }
+ };
+
+public:
+ // [flat.map.cons], construct/copy/destroy
+ _LIBCPP_HIDE_FROM_ABI flat_map() noexcept(
+ is_nothrow_default_constructible_v<_KeyContainer> && is_nothrow_default_constructible_v<_MappedContainer> &&
+ is_nothrow_default_constructible_v<_Compare>)
+ : __containers_(), __compare_() {}
+
+ // copy/move constructors are not specified in the spec (defaulted)
+ // but move constructor can potentially leave moved from object in an inconsistent
+ // state if an exception is thrown
+ _LIBCPP_HIDE_FROM_ABI flat_map(const flat_map&) = default;
+
+ _LIBCPP_HIDE_FROM_ABI flat_map(flat_map&& __other) noexcept(
+ is_nothrow_move_constructible_v<_KeyContainer> && is_nothrow_move_constructible_v<_MappedContainer> &&
+ is_nothrow_move_constructible_v<_Compare>) try
+ : __containers_(std::move(__other.__containers_)), __compare_(std::move(__other.__compare_)) {
+ __other.clear();
+ } catch (...) {
+ __other.clear();
+ throw;
+ }
+
+ template <class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI flat_map(const flat_map& __other, const _Allocator& __alloc)
+ : flat_map(__ctor_uses_allocator_tag{},
+ __alloc,
+ __other.__containers_.keys,
+ __other.__containers_.values,
+ __other.__compare_) {}
+
+ template <class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI flat_map(flat_map&& __other, const _Allocator& __alloc) try
+ : flat_map(__ctor_uses_allocator_tag{},
+ __alloc,
+ std::move(__other.__containers_.keys),
+ std::move(__other.__containers_.values),
+ std::move(__other.__compare_)) {
+ __other.clear();
+ } catch (...) {
+ __other.clear();
+ throw;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI flat_map(
+ key_container_type __key_cont, mapped_container_type __mapped_cont, const key_compare& __comp = key_compare())
+ : __containers_{.keys = std::move(__key_cont), .values = std::move(__mapped_cont)}, __compare_(__comp) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(__containers.keys.size() == __containers.values.size(),
+ "flat_map keys and mapped containers have different size");
+ __sort_and_unique();
+ }
+
+ template <class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI
+ flat_map(const key_container_type& __key_cont, const mapped_container_type& __mapped_cont, const _Allocator& __alloc)
+ : flat_map(__ctor_uses_allocator_tag{}, __alloc, __key_cont, __mapped_cont) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(__containers.keys.size() == __containers.values.size(),
+ "flat_map keys and mapped containers have different size");
+ __sort_and_unique();
+ }
+
+ template <class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI
+ flat_map(const key_container_type& __key_cont,
+ const mapped_container_type& __mapped_cont,
+ const key_compare& __comp,
+ const _Allocator& __alloc)
+ : flat_map(__ctor_uses_allocator_tag{}, __alloc, __key_cont, __mapped_cont, __comp) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(__containers.keys.size() == __containers.values.size(),
+ "flat_map keys and mapped containers have different size");
+ __sort_and_unique();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI
+ flat_map(sorted_unique_t,
+ key_container_type __key_cont,
+ mapped_container_type __mapped_cont,
+ const key_compare& __comp = key_compare())
+ : __containers_{.keys = std::move(__key_cont), .values = std::move(__mapped_cont)}, __compare_(__comp) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(__containers.keys.size() == __containers.values.size(),
+ "flat_map keys and mapped containers have different size");
+ _LIBCPP_ASSERT_SEMANTIC_REQUIREMENT(
+ __is_sorted_and_unique(__containers.keys), "Either the key container is not sorted or it contains duplicates");
+ }
+
+ template <class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI
+ flat_map(sorted_unique_t,
+ const key_container_type& __key_cont,
+ const mapped_container_type& __mapped_cont,
+ const _Allocator& __alloc)
+ : flat_map(__ctor_uses_allocator_tag{}, __alloc, __key_cont, __mapped_cont) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(__containers.keys.size() == __containers.values.size(),
+ "flat_map keys and mapped containers have different size");
+ _LIBCPP_ASSERT_SEMANTIC_REQUIREMENT(
+ __is_sorted_and_unique(__containers.keys), "Either the key container is not sorted or it contains duplicates");
+ }
+
+ template <class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI
+ flat_map(sorted_unique_t,
+ const key_container_type& __key_cont,
+ const mapped_container_type& __mapped_cont,
+ const key_compare& __comp,
+ const _Allocator& __alloc)
+ : flat_map(__ctor_uses_allocator_tag{}, __alloc, __key_cont, __mapped_cont, __comp) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(__containers.keys.size() == __containers.values.size(),
+ "flat_map keys and mapped containers have different size");
+ _LIBCPP_ASSERT_SEMANTIC_REQUIREMENT(
+ __is_sorted_and_unique(__containers.keys), "Either the key container is not sorted or it contains duplicates");
+ }
+
+ _LIBCPP_HIDE_FROM_ABI explicit flat_map(const key_compare& __comp) : __containers_(), __compare_(__comp) {}
+
+ template <class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI flat_map(const key_compare& __comp, const _Allocator& __alloc)
+ : flat_map(__ctor_uses_allocator_empty_tag{}, __alloc, __comp) {}
+
+ template <class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI explicit flat_map(const _Allocator& __alloc)
+ : flat_map(__ctor_uses_allocator_empty_tag{}, __alloc) {}
+
+ template <input_iterator _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI
+ flat_map(_InputIterator __first, _InputIterator __last, const key_compare& __comp = key_compare())
+ : __containers_(), __compare_(__comp) {
+ insert(__first, __last);
+ }
+
+ template <input_iterator _InputIterator, class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI
+ flat_map(_InputIterator __first, _InputIterator __last, const key_compare& __comp, const _Allocator& __alloc)
+ : flat_map(__ctor_uses_allocator_empty_tag{}, __alloc, __comp) {
+ insert(__first, __last);
+ }
+
+ template <input_iterator _InputIterator, class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI flat_map(_InputIterator __first, _InputIterator __last, const _Allocator& __alloc)
+ : flat_map(__ctor_uses_allocator_empty_tag{}, __alloc) {
+ insert(__first, __last);
+ }
+
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI flat_map(from_range_t __fr, _Range&& __rg)
+ : flat_map(__fr, std::forward<_Range>(__rg), key_compare()) {}
+
+ template <_ContainerCompatibleRange<value_type> _Range, class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI flat_map(from_range_t, _Range&& __rg, const _Allocator& __alloc)
+ : flat_map(__ctor_uses_allocator_empty_tag{}, __alloc) {
+ insert_range(std::forward<_Range>(__rg));
+ }
+
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI flat_map(from_range_t, _Range&& __rg, const key_compare& __comp) : flat_map(__comp) {
+ insert_range(std::forward<_Range>(__rg));
+ }
+
+ template <_ContainerCompatibleRange<value_type> _Range, class _Allocator>
+ _LIBCPP_HIDE_FROM_ABI flat_map(from_range_t, _Range&& __rg, const key_compare& __comp, const _Allocator& __alloc)
+ : flat_map(__ctor_uses_allocator_empty_tag{}, __alloc, __comp) {
+ insert_range(std::forward<_Range>(__rg));
+ }
+
+ template <input_iterator _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI
+ flat_map(sorted_unique_t, _InputIterator __first, _InputIterator __last, const key_compare& __comp = key_compare())
+ : __containers_(), __compare_(__comp) {
+ insert(sorted_unique, __first, __last);
+ }
+ template <input_iterator _InputIterator, class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI
+ flat_map(sorted_unique_t,
+ _InputIterator __first,
+ _InputIterator __last,
+ const key_compare& __comp,
+ const _Allocator& __alloc)
+ : flat_map(__ctor_uses_allocator_empty_tag{}, __alloc, __comp) {
+ insert(sorted_unique, __first, __last);
+ }
+
+ template <input_iterator _InputIterator, class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI
+ flat_map(sorted_unique_t, _InputIterator __first, _InputIterator __last, const _Allocator& __alloc)
+ : flat_map(__ctor_uses_allocator_empty_tag{}, __alloc) {
+ insert(sorted_unique, __first, __last);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI flat_map(initializer_list<value_type> __il, const key_compare& __comp = key_compare())
+ : flat_map(__il.begin(), __il.end(), __comp) {}
+
+ template <class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI
+ flat_map(initializer_list<value_type> __il, const key_compare& __comp, const _Allocator& __alloc)
+ : flat_map(__il.begin(), __il.end(), __comp, __alloc) {}
+
+ template <class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI flat_map(initializer_list<value_type> __il, const _Allocator& __alloc)
+ : flat_map(__il.begin(), __il.end(), __alloc) {}
+
+ _LIBCPP_HIDE_FROM_ABI
+ flat_map(sorted_unique_t, initializer_list<value_type> __il, const key_compare& __comp = key_compare())
+ : flat_map(sorted_unique, __il.begin(), __il.end(), __comp) {}
+
+ template <class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI
+ flat_map(sorted_unique_t, initializer_list<value_type> __il, const key_compare& __comp, const _Allocator& __alloc)
+ : flat_map(sorted_unique, __il.begin(), __il.end(), __comp, __alloc) {}
+
+ template <class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI flat_map(sorted_unique_t, initializer_list<value_type> __il, const _Allocator& __alloc)
+ : flat_map(sorted_unique, __il.begin(), __il.end(), __alloc) {}
+
+ _LIBCPP_HIDE_FROM_ABI flat_map& operator=(initializer_list<value_type> __il) {
+ clear();
+ insert(__il);
+ return *this;
+ }
+
+ // copy/move assignment are not specified in the spec (defaulted)
+ // but move assignment can potentially leave moved from object in an inconsistent
+ // state if an exception is thrown
+ _LIBCPP_HIDE_FROM_ABI flat_map& operator=(const flat_map&) = default;
+
+ _LIBCPP_HIDE_FROM_ABI flat_map& operator=(flat_map&& __other) noexcept(
+ is_nothrow_move_assignable_v<_KeyContainer> && is_nothrow_move_assignable_v<_MappedContainer> &&
+ is_nothrow_move_assignable_v<_Compare>) {
+ auto __clear_other_guard = std::__make_scoped_guard([&]() noexcept { __other.clear() /* noexcept */; });
+ auto __clear_self_guard = std::__make_exception_guard([&]() noexcept { clear() /* noexcept */; });
+ __containers_ = std::move(__other.__containers_);
+ __compare_ = std::move(__other.__compare_);
+ __clear_self_guard.__complete();
+ return *this;
+ }
+
+ // iterators
+ _LIBCPP_HIDE_FROM_ABI iterator begin() noexcept {
+ return iterator(__containers_.keys.begin(), __containers_.values.begin());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI const_iterator begin() const noexcept {
+ return const_iterator(__containers_.keys.begin(), __containers_.values.begin());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator end() noexcept {
+ return iterator(__containers_.keys.end(), __containers_.values.end());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI const_iterator end() const noexcept {
+ return const_iterator(__containers_.keys.end(), __containers_.values.end());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI reverse_iterator rbegin() noexcept { return reverse_iterator(end()); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator rbegin() const noexcept { const_reverse_iterator(end()); }
+ _LIBCPP_HIDE_FROM_ABI reverse_iterator rend() noexcept { return reverse_iterator(begin()); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator rend() const noexcept { return const_reverse_iterator(begin()); }
+
+ _LIBCPP_HIDE_FROM_ABI const_iterator cbegin() const noexcept { return begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator cend() const noexcept { return end(); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator crbegin() const noexcept { return const_reverse_iterator(end()); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator crend() const noexcept { return const_reverse_iterator(begin()); }
+
+ // [flat.map.capacity], capacity
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI bool empty() const noexcept { return __containers_.keys.empty(); }
+
+ _LIBCPP_HIDE_FROM_ABI size_type size() const noexcept { return __containers_.keys.size(); }
+
+ _LIBCPP_HIDE_FROM_ABI size_type max_size() const noexcept {
+ return std::min<size_type>(__containers_.keys.max_size(), __containers_.values.max_size());
+ }
+
+ // [flat.map.access], element access
+ _LIBCPP_HIDE_FROM_ABI mapped_type& operator[](const key_type& __x) { return try_emplace(__x).first->second; }
+
+ _LIBCPP_HIDE_FROM_ABI mapped_type& operator[](key_type&& __x) { return try_emplace(std::move(__x)).first->second; }
+
+ template <class _Kp>
+ requires __is_compare_transparent
+ _LIBCPP_HIDE_FROM_ABI mapped_type& operator[](_Kp&& __x) {
+ return try_emplace(std::forward<_Kp>(__x)).first->second;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI mapped_type& at(const key_type& __x) {
+ auto __it = find(__x);
+ if (__it == end()) {
+ std::__throw_out_of_range("flat_map::at(const key_type&): Key does not exist");
+ }
+ return (*__it).second;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI const mapped_type& at(const key_type& __x) const {
+ auto __it = find(__x);
+ if (__it == end()) {
+ std::__throw_out_of_range("flat_map::at(const key_type&) const: Key does not exist");
+ }
+ return (*__it).second;
+ }
+
+ template <class _Kp>
+ requires __is_compare_transparent
+ _LIBCPP_HIDE_FROM_ABI mapped_type& at(const _Kp& __x) {
+ static_assert(requires { find(__x); }, "flat_map::at(const K& x): find(x) needs to be well-formed");
+ auto __it = find(__x);
+ if (__it == end()) {
+ std::__throw_out_of_range("flat_map::at(const K&): Key does not exist");
+ }
+ return (*__it).second;
+ }
+
+ template <class _Kp>
+ requires __is_compare_transparent
+ _LIBCPP_HIDE_FROM_ABI const mapped_type& at(const _Kp& __x) const {
+ static_assert(requires { find(__x); }, "flat_map::at(const K& x) const: find(x) needs to be well-formed");
+ auto __it = find(__x);
+ if (__it == end()) {
+ std::__throw_out_of_range("flat_map::at(const K&) const: Key does not exist");
+ }
+ return (*__it).second;
+ }
+
+ // [flat.map.modifiers], modifiers
+ template <class... _Args>
+ requires is_constructible_v<pair<key_type, mapped_type>, _Args...>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> emplace(_Args&&... __args) {
+ std::pair<key_type, mapped_type> __pair(std::forward<_Args>(__args)...);
+ return __binary_search_emplace_impl(std::move(__pair));
+ }
+
+ template <class... _Args>
+ requires is_constructible_v<pair<key_type, mapped_type>, _Args...>
+ _LIBCPP_HIDE_FROM_ABI iterator emplace_hint(const_iterator __hint, _Args&&... __args) {
+ std::pair<key_type, mapped_type> __pair(std::forward<_Args>(__args)...);
+ if (__is_hint_correct(__hint, __pair.first)) {
+ if (__compare_(__pair.first, __hint->first)) {
+ return __emplace_impl(__hint, std::move(__pair));
+ } else {
+ // key equals
+ auto __dist = __hint - cbegin();
+ return iterator(__containers_.keys.begin() + __dist, __containers_.values.begin() + __dist);
+ }
+ } else {
+ return __binary_search_emplace_impl(std::move(__pair)).first;
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> insert(const value_type& __x) { return emplace(__x); }
+
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> insert(value_type&& __x) { return emplace(std::move(__x)); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __hint, const value_type& __x) {
+ return emplace_hint(__hint, __x);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __hint, value_type&& __x) {
+ return emplace_hint(__hint, std::move(__x));
+ }
+
+ template <class _Pp>
+ requires is_constructible_v<pair<key_type, mapped_type>, _Pp>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> insert(_Pp&& __x) {
+ return emplace(std::forward<_Pp>(__x));
+ }
+
+ template <class _Pp>
+ requires is_constructible_v<pair<key_type, mapped_type>, _Pp>
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __hint, _Pp&& __x) {
+ return emplace_hint(__hint, std::forward<_Pp>(__x));
+ }
+
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI void insert(_InputIterator __first, _InputIterator __last) {
+ if constexpr (sized_sentinel_for<_InputIterator, _InputIterator>) {
+ __reserve_impl(__last - __first);
+ }
+ __append_sort_merge_unique</*WasSorted = */ false>(std::move(__first), std::move(__last));
+ }
+
+ template <input_iterator _InputIterator>
+ void insert(sorted_unique_t, _InputIterator __first, _InputIterator __last) {
+ if constexpr (sized_sentinel_for<_InputIterator, _InputIterator>) {
+ __reserve_impl(__last - __first);
+ }
+
+ __append_sort_merge_unique</*WasSorted = */ true>(std::move(__first), std::move(__last));
+ }
+
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI void insert_range(_Range&& __range) {
+ if constexpr (ranges::sized_range<_Range>) {
+ __reserve_impl(ranges::size(__range));
+ }
+
+ __append_sort_merge_unique</*WasSorted = */ false>(ranges::begin(__range), ranges::end(__range));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void insert(initializer_list<value_type> __il) { insert(__il.begin(), __il.end()); }
+
+ _LIBCPP_HIDE_FROM_ABI void insert(sorted_unique_t, initializer_list<value_type> __il) {
+ insert(sorted_unique, __il.begin(), __il.end());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI containers extract() && {
+ auto __guard = std::__make_scoped_guard([&]() noexcept { clear() /* noexcept */; });
+ auto __ret = std::move(__containers_);
+ return __ret;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void replace(key_container_type&& __key_cont, mapped_container_type&& __mapped_cont) {
+ auto __guard = std::__make_exception_guard([&]() noexcept { clear() /* noexcept */; });
+ __containers_.keys = std::move(__key_cont);
+ __containers_.values = std::move(__mapped_cont);
+ __guard.__complete();
+ }
+
+ template <class... _Args>
+ requires is_constructible_v<mapped_type, _Args...>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> try_emplace(const key_type& __key, _Args&&... __args) {
+ return __binary_search_try_emplace_impl(__key, std::forward<_Args>(__args)...);
+ }
+
+ template <class... _Args>
+ requires is_constructible_v<mapped_type, _Args...>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> try_emplace(key_type&& __key, _Args&&... __args) {
+ return __binary_search_try_emplace_impl(std::move(__key), std::forward<_Args>(__args)...);
+ }
+
+ template <class _Kp, class... _Args>
+ requires __is_compare_transparent && is_constructible_v<key_type, _Kp> &&
+ is_constructible_v<mapped_type, _Args...> && is_convertible_v<_Kp&&, const_iterator> &&
+ is_convertible_v<_Kp&&, iterator>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> try_emplace(_Kp&& __key, _Args&&... __args) {
+ return __binary_search_try_emplace_impl(std::forward<_Kp>(__key), std::forward<_Args>(__args)...);
+ }
+
+ template <class... _Args>
+ requires is_constructible_v<mapped_type, _Args...>
+ _LIBCPP_HIDE_FROM_ABI iterator try_emplace(const_iterator __hint, const key_type& __key, _Args&&... __args) {
+ return try_emplace_hint_impl(__hint, __key, std::forward<_Args>(__args)...);
+ }
+
+ template <class... _Args>
+ requires is_constructible_v<mapped_type, _Args...>
+ _LIBCPP_HIDE_FROM_ABI iterator try_emplace(const_iterator __hint, key_type&& __key, _Args&&... __args) {
+ return try_emplace_hint_impl(__hint, std::move(__key), std::forward<_Args>(__args)...);
+ }
+
+ template <class _Kp, class... _Args>
+ requires __is_compare_transparent && is_constructible_v<key_type, _Kp> && is_constructible_v<mapped_type, _Args...>
+ _LIBCPP_HIDE_FROM_ABI iterator try_emplace(const_iterator __hint, _Kp&& __key, _Args&&... __args) {
+ return try_emplace_hint_impl(__hint, std::forward<_Kp>(__key), std::forward<_Args>(__args)...);
+ }
+
+ template <class _Mapped>
+ requires is_assignable_v<mapped_type&, _Mapped> && is_constructible_v<mapped_type, _Mapped>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> insert_or_assign(const key_type& __key, _Mapped&& __obj) {
+ return __insert_or_assign_impl(__key, std::forward<_Mapped>(__obj));
+ }
+
+ template <class _Mapped>
+ requires is_assignable_v<mapped_type&, _Mapped> && is_constructible_v<mapped_type, _Mapped>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> insert_or_assign(key_type&& __key, _Mapped&& __obj) {
+ return __insert_or_assign_impl(std::move(__key), std::forward<_Mapped>(__obj));
+ }
+
+ template <class _Kp, class _Mapped>
+ requires __is_compare_transparent && is_constructible_v<key_type, _Kp> && is_assignable_v<mapped_type&, _Mapped> &&
+ is_constructible_v<mapped_type, _Mapped>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> insert_or_assign(_Kp&& __key, _Mapped&& __obj) {
+ return __insert_or_assign_impl(std::forward<_Kp>(__key), std::forward<_Mapped>(__obj));
+ }
+
+ template <class _Mapped>
+ requires is_assignable_v<mapped_type&, _Mapped> && is_constructible_v<mapped_type, _Mapped>
+ _LIBCPP_HIDE_FROM_ABI iterator insert_or_assign(const_iterator __hint, const key_type& __key, _Mapped&& __obj) {
+ return __insert_or_assign_impl(__key, std::forward<_Mapped>(__obj), __hint).first;
+ }
+
+ template <class _Mapped>
+ requires is_assignable_v<mapped_type&, _Mapped> && is_constructible_v<mapped_type, _Mapped>
+ _LIBCPP_HIDE_FROM_ABI iterator insert_or_assign(const_iterator __hint, key_type&& __key, _Mapped&& __obj) {
+ return __insert_or_assign_impl(std::move(__key), std::forward<_Mapped>(__obj), __hint).first;
+ }
+
+ template <class _Kp, class _Mapped>
+ requires __is_compare_transparent && is_constructible_v<key_type, _Kp> && is_assignable_v<mapped_type&, _Mapped> &&
+ is_constructible_v<mapped_type, _Mapped>
+ _LIBCPP_HIDE_FROM_ABI iterator insert_or_assign(const_iterator __hint, _Kp&& __key, _Mapped&& __obj) {
+ return __insert_or_assign_impl(std::forward<_Kp>(__key), std::forward<_Mapped>(__obj), __hint).first;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator erase(iterator __position) {
+ return __erase_impl(__position.__key_iter_, __position.__mapped_iter_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __position) {
+ return __erase_impl(__position.__key_iter_, __position.__mapped_iter_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI size_type erase(const key_type& __x) {
+ auto __iter = find(__x);
+ if (__iter != end()) {
+ erase(__iter);
+ return 1;
+ }
+ return 0;
+ }
+
+ template <class _Kp>
+ requires(__is_compare_transparent && !is_convertible_v<_Kp &&, iterator> &&
+ !is_convertible_v<_Kp &&, const_iterator>)
+ _LIBCPP_HIDE_FROM_ABI size_type erase(_Kp&& __x) {
+ auto [__first, __last] = equal_range(__x);
+ auto __res = __last - __first;
+ erase(__first, __last);
+ return __res;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __first, const_iterator __last) {
+ auto __on_failure = std::__make_exception_guard([&]() noexcept { clear() /* noexcept */; });
+ auto __key_it = __containers_.keys.erase(__first.__key_iter_, __last.__key_iter_);
+ auto __mapped_it = __containers_.values.erase(__first.__mapped_iter_, __last.__mapped_iter_);
+ __on_failure.__complete();
+ return iterator(std::move(__key_it), std::move(__mapped_it));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(flat_map& __y) noexcept {
+ auto __guard = std::__make_exception_guard([&]() noexcept {
+ clear() /* noexcept */;
+ __y.clear() /*noexcept*/;
+ });
+ using std::swap;
+ swap(__compare_, __y.__compare_);
+ swap(__containers_.keys, __y.__containers_.keys);
+ swap(__containers_.values, __y.__containers_.values);
+ __guard.__complete();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void clear() noexcept {
+ __containers_.keys.clear();
+ __containers_.values.clear();
+ }
+
+ // observers
+ _LIBCPP_HIDE_FROM_ABI key_compare key_comp() const { return __compare_; }
+ _LIBCPP_HIDE_FROM_ABI value_compare value_comp() const { return value_compare(__compare_); }
+ _LIBCPP_HIDE_FROM_ABI const key_container_type& keys() const noexcept { return __containers_.keys; }
+ _LIBCPP_HIDE_FROM_ABI const mapped_container_type& values() const noexcept { return __containers_.values; }
+
+ // map operations
+ _LIBCPP_HIDE_FROM_ABI iterator find(const key_type& __x) { return __find_impl(*this, __x); }
+
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const key_type& __x) const { return __find_impl(*this, __x); }
+
+ template <class _Kp>
+ requires __is_compare_transparent
+ _LIBCPP_HIDE_FROM_ABI iterator find(const _Kp& __x) {
+ return __find_impl(*this, __x);
+ }
+
+ template <class _Kp>
+ requires __is_compare_transparent
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const _Kp& __x) const {
+ return __find_impl(*this, __x);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI size_type count(const key_type& __x) const { return contains(__x) ? 1 : 0; }
+
+ template <class _Kp>
+ requires __is_compare_transparent
+ _LIBCPP_HIDE_FROM_ABI size_type count(const _Kp& __x) const {
+ auto [__first, __last] = __equal_range_return_key_iter(*this, __x);
+ return __last - __first;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI bool contains(const key_type& __x) const { return find(__x) != end(); }
+
+ template <class _Kp>
+ _LIBCPP_HIDE_FROM_ABI bool contains(const _Kp& __x) const {
+ return find(__x) != end();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator lower_bound(const key_type& __x) { return __lower_bound_impl<iterator>(*this, __x); }
+
+ _LIBCPP_HIDE_FROM_ABI const_iterator lower_bound(const key_type& __x) const {
+ return __lower_bound_impl<const_iterator>(*this, __x);
+ }
+
+ template <class _Kp>
+ requires __is_compare_transparent
+ _LIBCPP_HIDE_FROM_ABI iterator lower_bound(const _Kp& __x) {
+ return __lower_bound_impl<iterator>(*this, __x);
+ }
+
+ template <class _Kp>
+ requires __is_compare_transparent
+ _LIBCPP_HIDE_FROM_ABI const_iterator lower_bound(const _Kp& __x) const {
+ return __lower_bound_impl<const_iterator>(*this, __x);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator upper_bound(const key_type& __x) { return __upper_bound_impl<iterator>(*this, __x); }
+
+ _LIBCPP_HIDE_FROM_ABI const_iterator upper_bound(const key_type& __x) const {
+ return __upper_bound_impl<const_iterator>(*this, __x);
+ }
+
+ template <class _Kp>
+ requires __is_compare_transparent
+ _LIBCPP_HIDE_FROM_ABI iterator upper_bound(const _Kp& __x) {
+ return __upper_bound_impl<iterator>(*this, __x);
+ }
+
+ template <class _Kp>
+ requires __is_compare_transparent
+ _LIBCPP_HIDE_FROM_ABI const_iterator upper_bound(const _Kp& __x) const {
+ return __upper_bound_impl<iterator>(*this, __x);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, iterator> equal_range(const key_type& __x) {
+ return __equal_range_impl(*this, __x);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI pair<const_iterator, const_iterator> equal_range(const key_type& __x) const {
+ return __equal_range_impl(*this, __x);
+ }
+
+ template <class _Kp>
+ requires __is_compare_transparent
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, iterator> equal_range(const _Kp& __x) {
+ return __equal_range_impl(*this, __x);
+ }
+ template <class _Kp>
+ requires __is_compare_transparent
+ _LIBCPP_HIDE_FROM_ABI pair<const_iterator, const_iterator> equal_range(const _Kp& __x) const {
+ return __equal_range_impl(*this, __x);
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const flat_map& __x, const flat_map& __y) {
+ return ranges::equal(__x, __y);
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI auto operator<=>(const flat_map& __x, const flat_map& __y) {
+ return std::lexicographical_compare_three_way(
+ __x.begin(), __x.end(), __y.begin(), __y.end(), std::__synth_three_way);
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI void swap(flat_map& __x, flat_map& __y) noexcept { __x.swap(__y); }
+
+private:
+ struct __ctor_uses_allocator_tag {
+ explicit __ctor_uses_allocator_tag() = default;
+ };
+ struct __ctor_uses_allocator_empty_tag {
+ explicit __ctor_uses_allocator_empty_tag() = default;
+ };
+
+ template <class _Allocator, class _KeyCont, class _MappedCont, class... _CompArg>
+ _LIBCPP_HIDE_FROM_ABI
+ flat_map(__ctor_uses_allocator_tag,
+ const _Allocator& __alloc,
+ _KeyCont&& __key_cont,
+ _MappedCont&& __mapped_cont,
+ _CompArg&&... __comp)
+ : __containers_{.keys = std::make_obj_using_allocator<key_container_type>(
+ __alloc, std::forward<_KeyCont>(__key_cont)),
+ .values = std::make_obj_using_allocator<mapped_container_type>(
+ __alloc, std::forward<_MappedCont>(__mapped_cont))},
+ __compare_(std::forward<_CompArg>(__comp)...) {}
+
+ template <class _Allocator, class... _CompArg>
+ _LIBCPP_HIDE_FROM_ABI flat_map(__ctor_uses_allocator_empty_tag, const _Allocator& __alloc, _CompArg&&... __comp)
+ : __containers_{.keys = std::make_obj_using_allocator<key_container_type>(__alloc),
+ .values = std::make_obj_using_allocator<mapped_container_type>(__alloc)},
+ __compare_(std::forward<_CompArg>(__comp)...) {}
+
+ _LIBCPP_HIDE_FROM_ABI bool __is_sorted_and_unique(auto&& __key_container) const {
+ auto __greater_or_equal_to = [this](const auto& __x, const auto& __y) { return !__compare_(__x, __y); };
+ return ranges::adjacent_find(__key_container, __greater_or_equal_to) == ranges::end(__key_container);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __sort_and_unique() {
+ auto __zv = ranges::views::zip(__containers_.keys, __containers_.values);
+ ranges::stable_sort(__zv, __compare_, [](const auto& __p) -> decltype(auto) { return std::get<0>(__p); });
+ auto __dup_start = ranges::unique(__zv, __key_equiv(__compare_)).begin();
+ auto __dist = ranges::distance(__zv.begin(), __dup_start);
+ __containers_.keys.erase(__containers_.keys.begin() + __dist, __containers_.keys.end());
+ __containers_.values.erase(__containers_.values.begin() + __dist, __containers_.values.end());
+ }
+
+ template <class _InputIterator, class _Sentinel>
+ _LIBCPP_HIDE_FROM_ABI size_type __append_no_check(_InputIterator __first, _Sentinel __last) {
+ size_type __num_of_appended = 0;
+ for (; __first != __last; ++__first) {
+ value_type __kv = *__first;
+ __containers_.keys.insert(__containers_.keys.end(), std::move(__kv.first));
+ __containers_.values.insert(__containers_.values.end(), std::move(__kv.second));
+ ++__num_of_appended;
----------------
ldionne wrote:
Here we materialize the iterator's `value_type` and we insert the elements one by one. If we had some kind of "protocol" that allows us to detect that an iterator is in fact a product of other iterators, we could decompose it to get the underlying iterators in the product and pass that directly to the containers. That way, we could call the underlying container's range-based `insert` method instead of inserting elements one-by-one.
This would apply to e.g. a zip view over two vectors, or when inserting into a `flat_map` from another `flat_map`. And given that we have significant optimizations in e.g. `std::vector::insert(first, last)` for contiguous iterators, this could end up making a big difference.
Example idea:
```c++
template <class _InputIterator, class _Sentinel>
requires __is_product_iterator<_InputIterator>
_LIBCPP_HIDE_FROM_ABI size_type __append_no_check(_InputIterator __first, _Sentinel __last) {
auto __first1 = std::__get_product_iterator_element<0>(__first);
auto __first2 = std::__get_product_iterator_element<1>(__first);
auto __last1 = std::__get_product_iterator_element<0>(__last);
auto __last2 = std::__get_product_iterator_element<1>(__last);
size_type __before = __containers_.keys.size();
__containers_.keys.insert(__containers_.keys.end(), __first1, __last1);
size_type __after = __containers_.keys.size();
__containers_.values.insert(__containers_.values.end(), __first2, __last2);
size_type __num_of_appended = __after - __before; // can we do better than that?
// We could also have some kind of check like this, but we'd need to do that without making
// the assumption that __first & __last are random access.
_LIBCPP_ASSERT_INTERNAL((__last1 - __first1) == (__last2 - __first2), "something went horribly wrong");
return __num_of_appended;
}
```
This makes me think about segmented iterator. It's not a category by itself, but it provides a (very useful) side channel to provide additional information to various places in the library. We don't have to implement this optimization day one (in fact we probably shouldn't for simplicity), but I think we really should consider doing it as a follow-up.
CC @philnik777 since this is the kind of stuff you generally like
https://github.com/llvm/llvm-project/pull/98643
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