| // Copyright 2018 The Abseil Authors. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // https://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| // |
| // ----------------------------------------------------------------------------- |
| // File: btree_set.h |
| // ----------------------------------------------------------------------------- |
| // |
| // This header file defines B-tree sets: sorted associative containers of |
| // values. |
| // |
| // * `absl::btree_set<>` |
| // * `absl::btree_multiset<>` |
| // |
| // These B-tree types are similar to the corresponding types in the STL |
| // (`std::set` and `std::multiset`) and generally conform to the STL interfaces |
| // of those types. However, because they are implemented using B-trees, they |
| // are more efficient in most situations. |
| // |
| // Unlike `std::set` and `std::multiset`, which are commonly implemented using |
| // red-black tree nodes, B-tree sets use more generic B-tree nodes able to hold |
| // multiple values per node. Holding multiple values per node often makes |
| // B-tree sets perform better than their `std::set` counterparts, because |
| // multiple entries can be checked within the same cache hit. |
| // |
| // However, these types should not be considered drop-in replacements for |
| // `std::set` and `std::multiset` as there are some API differences, which are |
| // noted in this header file. The most consequential differences with respect to |
| // migrating to b-tree from the STL types are listed in the next paragraph. |
| // Other API differences are minor. |
| // |
| // Importantly, insertions and deletions may invalidate outstanding iterators, |
| // pointers, and references to elements. Such invalidations are typically only |
| // an issue if insertion and deletion operations are interleaved with the use of |
| // more than one iterator, pointer, or reference simultaneously. For this |
| // reason, `insert()` and `erase()` return a valid iterator at the current |
| // position. |
| |
| #ifndef ABSL_CONTAINER_BTREE_SET_H_ |
| #define ABSL_CONTAINER_BTREE_SET_H_ |
| |
| #include "absl/container/internal/btree.h" // IWYU pragma: export |
| #include "absl/container/internal/btree_container.h" // IWYU pragma: export |
| |
| namespace absl { |
| ABSL_NAMESPACE_BEGIN |
| |
| namespace container_internal { |
| |
| template <typename Key> |
| struct set_slot_policy; |
| |
| template <typename Key, typename Compare, typename Alloc, int TargetNodeSize, |
| bool IsMulti> |
| struct set_params; |
| |
| } // namespace container_internal |
| |
| // absl::btree_set<> |
| // |
| // An `absl::btree_set<K>` is an ordered associative container of unique key |
| // values designed to be a more efficient replacement for `std::set` (in most |
| // cases). |
| // |
| // Keys are sorted using an (optional) comparison function, which defaults to |
| // `std::less<K>`. |
| // |
| // An `absl::btree_set<K>` uses a default allocator of `std::allocator<K>` to |
| // allocate (and deallocate) nodes, and construct and destruct values within |
| // those nodes. You may instead specify a custom allocator `A` (which in turn |
| // requires specifying a custom comparator `C`) as in |
| // `absl::btree_set<K, C, A>`. |
| // |
| template <typename Key, typename Compare = std::less<Key>, |
| typename Alloc = std::allocator<Key>> |
| class btree_set |
| : public container_internal::btree_set_container< |
| container_internal::btree<container_internal::set_params< |
| Key, Compare, Alloc, /*TargetNodeSize=*/256, |
| /*IsMulti=*/false>>> { |
| using Base = typename btree_set::btree_set_container; |
| |
| public: |
| // Constructors and Assignment Operators |
| // |
| // A `btree_set` supports the same overload set as `std::set` |
| // for construction and assignment: |
| // |
| // * Default constructor |
| // |
| // absl::btree_set<std::string> set1; |
| // |
| // * Initializer List constructor |
| // |
| // absl::btree_set<std::string> set2 = |
| // {{"huey"}, {"dewey"}, {"louie"},}; |
| // |
| // * Copy constructor |
| // |
| // absl::btree_set<std::string> set3(set2); |
| // |
| // * Copy assignment operator |
| // |
| // absl::btree_set<std::string> set4; |
| // set4 = set3; |
| // |
| // * Move constructor |
| // |
| // // Move is guaranteed efficient |
| // absl::btree_set<std::string> set5(std::move(set4)); |
| // |
| // * Move assignment operator |
| // |
| // // May be efficient if allocators are compatible |
| // absl::btree_set<std::string> set6; |
| // set6 = std::move(set5); |
| // |
| // * Range constructor |
| // |
| // std::vector<std::string> v = {"a", "b"}; |
| // absl::btree_set<std::string> set7(v.begin(), v.end()); |
| btree_set() {} |
| using Base::Base; |
| |
| // btree_set::begin() |
| // |
| // Returns an iterator to the beginning of the `btree_set`. |
| using Base::begin; |
| |
| // btree_set::cbegin() |
| // |
| // Returns a const iterator to the beginning of the `btree_set`. |
| using Base::cbegin; |
| |
| // btree_set::end() |
| // |
| // Returns an iterator to the end of the `btree_set`. |
| using Base::end; |
| |
| // btree_set::cend() |
| // |
| // Returns a const iterator to the end of the `btree_set`. |
| using Base::cend; |
| |
| // btree_set::empty() |
| // |
| // Returns whether or not the `btree_set` is empty. |
| using Base::empty; |
| |
| // btree_set::max_size() |
| // |
| // Returns the largest theoretical possible number of elements within a |
| // `btree_set` under current memory constraints. This value can be thought |
| // of as the largest value of `std::distance(begin(), end())` for a |
| // `btree_set<Key>`. |
| using Base::max_size; |
| |
| // btree_set::size() |
| // |
| // Returns the number of elements currently within the `btree_set`. |
| using Base::size; |
| |
| // btree_set::clear() |
| // |
| // Removes all elements from the `btree_set`. Invalidates any references, |
| // pointers, or iterators referring to contained elements. |
| using Base::clear; |
| |
| // btree_set::erase() |
| // |
| // Erases elements within the `btree_set`. Overloads are listed below. |
| // |
| // iterator erase(iterator position): |
| // iterator erase(const_iterator position): |
| // |
| // Erases the element at `position` of the `btree_set`, returning |
| // the iterator pointing to the element after the one that was erased |
| // (or end() if none exists). |
| // |
| // iterator erase(const_iterator first, const_iterator last): |
| // |
| // Erases the elements in the open interval [`first`, `last`), returning |
| // the iterator pointing to the element after the interval that was erased |
| // (or end() if none exists). |
| // |
| // template <typename K> size_type erase(const K& key): |
| // |
| // Erases the element with the matching key, if it exists, returning the |
| // number of elements erased (0 or 1). |
| using Base::erase; |
| |
| // btree_set::insert() |
| // |
| // Inserts an element of the specified value into the `btree_set`, |
| // returning an iterator pointing to the newly inserted element, provided that |
| // an element with the given key does not already exist. If an insertion |
| // occurs, any references, pointers, or iterators are invalidated. |
| // Overloads are listed below. |
| // |
| // std::pair<iterator,bool> insert(const value_type& value): |
| // |
| // Inserts a value into the `btree_set`. Returns a pair consisting of an |
| // iterator to the inserted element (or to the element that prevented the |
| // insertion) and a bool denoting whether the insertion took place. |
| // |
| // std::pair<iterator,bool> insert(value_type&& value): |
| // |
| // Inserts a moveable value into the `btree_set`. Returns a pair |
| // consisting of an iterator to the inserted element (or to the element that |
| // prevented the insertion) and a bool denoting whether the insertion took |
| // place. |
| // |
| // iterator insert(const_iterator hint, const value_type& value): |
| // iterator insert(const_iterator hint, value_type&& value): |
| // |
| // Inserts a value, using the position of `hint` as a non-binding suggestion |
| // for where to begin the insertion search. Returns an iterator to the |
| // inserted element, or to the existing element that prevented the |
| // insertion. |
| // |
| // void insert(InputIterator first, InputIterator last): |
| // |
| // Inserts a range of values [`first`, `last`). |
| // |
| // void insert(std::initializer_list<init_type> ilist): |
| // |
| // Inserts the elements within the initializer list `ilist`. |
| using Base::insert; |
| |
| // btree_set::emplace() |
| // |
| // Inserts an element of the specified value by constructing it in-place |
| // within the `btree_set`, provided that no element with the given key |
| // already exists. |
| // |
| // The element may be constructed even if there already is an element with the |
| // key in the container, in which case the newly constructed element will be |
| // destroyed immediately. |
| // |
| // If an insertion occurs, any references, pointers, or iterators are |
| // invalidated. |
| using Base::emplace; |
| |
| // btree_set::emplace_hint() |
| // |
| // Inserts an element of the specified value by constructing it in-place |
| // within the `btree_set`, using the position of `hint` as a non-binding |
| // suggestion for where to begin the insertion search, and only inserts |
| // provided that no element with the given key already exists. |
| // |
| // The element may be constructed even if there already is an element with the |
| // key in the container, in which case the newly constructed element will be |
| // destroyed immediately. |
| // |
| // If an insertion occurs, any references, pointers, or iterators are |
| // invalidated. |
| using Base::emplace_hint; |
| |
| // btree_set::extract() |
| // |
| // Extracts the indicated element, erasing it in the process, and returns it |
| // as a C++17-compatible node handle. Overloads are listed below. |
| // |
| // node_type extract(const_iterator position): |
| // |
| // Extracts the element at the indicated position and returns a node handle |
| // owning that extracted data. |
| // |
| // template <typename K> node_type extract(const K& k): |
| // |
| // Extracts the element with the key matching the passed key value and |
| // returns a node handle owning that extracted data. If the `btree_set` |
| // does not contain an element with a matching key, this function returns an |
| // empty node handle. |
| // |
| // NOTE: In this context, `node_type` refers to the C++17 concept of a |
| // move-only type that owns and provides access to the elements in associative |
| // containers (https://en.cppreference.com/w/cpp/container/node_handle). |
| // It does NOT refer to the data layout of the underlying btree. |
| using Base::extract; |
| |
| // btree_set::merge() |
| // |
| // Extracts elements from a given `source` btree_set into this |
| // `btree_set`. If the destination `btree_set` already contains an |
| // element with an equivalent key, that element is not extracted. |
| using Base::merge; |
| |
| // btree_set::swap(btree_set& other) |
| // |
| // Exchanges the contents of this `btree_set` with those of the `other` |
| // btree_set, avoiding invocation of any move, copy, or swap operations on |
| // individual elements. |
| // |
| // All iterators and references on the `btree_set` remain valid, excepting |
| // for the past-the-end iterator, which is invalidated. |
| using Base::swap; |
| |
| // btree_set::contains() |
| // |
| // template <typename K> bool contains(const K& key) const: |
| // |
| // Determines whether an element comparing equal to the given `key` exists |
| // within the `btree_set`, returning `true` if so or `false` otherwise. |
| // |
| // Supports heterogeneous lookup, provided that the set has a compatible |
| // heterogeneous comparator. |
| using Base::contains; |
| |
| // btree_set::count() |
| // |
| // template <typename K> size_type count(const K& key) const: |
| // |
| // Returns the number of elements comparing equal to the given `key` within |
| // the `btree_set`. Note that this function will return either `1` or `0` |
| // since duplicate elements are not allowed within a `btree_set`. |
| // |
| // Supports heterogeneous lookup, provided that the set has a compatible |
| // heterogeneous comparator. |
| using Base::count; |
| |
| // btree_set::equal_range() |
| // |
| // Returns a closed range [first, last], defined by a `std::pair` of two |
| // iterators, containing all elements with the passed key in the |
| // `btree_set`. |
| using Base::equal_range; |
| |
| // btree_set::find() |
| // |
| // template <typename K> iterator find(const K& key): |
| // template <typename K> const_iterator find(const K& key) const: |
| // |
| // Finds an element with the passed `key` within the `btree_set`. |
| // |
| // Supports heterogeneous lookup, provided that the set has a compatible |
| // heterogeneous comparator. |
| using Base::find; |
| |
| // btree_set::lower_bound() |
| // |
| // template <typename K> iterator lower_bound(const K& key): |
| // template <typename K> const_iterator lower_bound(const K& key) const: |
| // |
| // Finds the first element that is not less than `key` within the `btree_set`. |
| // |
| // Supports heterogeneous lookup, provided that the set has a compatible |
| // heterogeneous comparator. |
| using Base::lower_bound; |
| |
| // btree_set::upper_bound() |
| // |
| // template <typename K> iterator upper_bound(const K& key): |
| // template <typename K> const_iterator upper_bound(const K& key) const: |
| // |
| // Finds the first element that is greater than `key` within the `btree_set`. |
| // |
| // Supports heterogeneous lookup, provided that the set has a compatible |
| // heterogeneous comparator. |
| using Base::upper_bound; |
| |
| // btree_set::get_allocator() |
| // |
| // Returns the allocator function associated with this `btree_set`. |
| using Base::get_allocator; |
| |
| // btree_set::key_comp(); |
| // |
| // Returns the key comparator associated with this `btree_set`. |
| using Base::key_comp; |
| |
| // btree_set::value_comp(); |
| // |
| // Returns the value comparator associated with this `btree_set`. The keys to |
| // sort the elements are the values themselves, therefore `value_comp` and its |
| // sibling member function `key_comp` are equivalent. |
| using Base::value_comp; |
| }; |
| |
| // absl::swap(absl::btree_set<>, absl::btree_set<>) |
| // |
| // Swaps the contents of two `absl::btree_set` containers. |
| template <typename K, typename C, typename A> |
| void swap(btree_set<K, C, A> &x, btree_set<K, C, A> &y) { |
| return x.swap(y); |
| } |
| |
| // absl::erase_if(absl::btree_set<>, Pred) |
| // |
| // Erases all elements that satisfy the predicate pred from the container. |
| // Returns the number of erased elements. |
| template <typename K, typename C, typename A, typename Pred> |
| typename btree_set<K, C, A>::size_type erase_if(btree_set<K, C, A> &set, |
| Pred pred) { |
| return container_internal::btree_access::erase_if(set, std::move(pred)); |
| } |
| |
| // absl::btree_multiset<> |
| // |
| // An `absl::btree_multiset<K>` is an ordered associative container of |
| // keys and associated values designed to be a more efficient replacement |
| // for `std::multiset` (in most cases). Unlike `absl::btree_set`, a B-tree |
| // multiset allows equivalent elements. |
| // |
| // Keys are sorted using an (optional) comparison function, which defaults to |
| // `std::less<K>`. |
| // |
| // An `absl::btree_multiset<K>` uses a default allocator of `std::allocator<K>` |
| // to allocate (and deallocate) nodes, and construct and destruct values within |
| // those nodes. You may instead specify a custom allocator `A` (which in turn |
| // requires specifying a custom comparator `C`) as in |
| // `absl::btree_multiset<K, C, A>`. |
| // |
| template <typename Key, typename Compare = std::less<Key>, |
| typename Alloc = std::allocator<Key>> |
| class btree_multiset |
| : public container_internal::btree_multiset_container< |
| container_internal::btree<container_internal::set_params< |
| Key, Compare, Alloc, /*TargetNodeSize=*/256, |
| /*IsMulti=*/true>>> { |
| using Base = typename btree_multiset::btree_multiset_container; |
| |
| public: |
| // Constructors and Assignment Operators |
| // |
| // A `btree_multiset` supports the same overload set as `std::set` |
| // for construction and assignment: |
| // |
| // * Default constructor |
| // |
| // absl::btree_multiset<std::string> set1; |
| // |
| // * Initializer List constructor |
| // |
| // absl::btree_multiset<std::string> set2 = |
| // {{"huey"}, {"dewey"}, {"louie"},}; |
| // |
| // * Copy constructor |
| // |
| // absl::btree_multiset<std::string> set3(set2); |
| // |
| // * Copy assignment operator |
| // |
| // absl::btree_multiset<std::string> set4; |
| // set4 = set3; |
| // |
| // * Move constructor |
| // |
| // // Move is guaranteed efficient |
| // absl::btree_multiset<std::string> set5(std::move(set4)); |
| // |
| // * Move assignment operator |
| // |
| // // May be efficient if allocators are compatible |
| // absl::btree_multiset<std::string> set6; |
| // set6 = std::move(set5); |
| // |
| // * Range constructor |
| // |
| // std::vector<std::string> v = {"a", "b"}; |
| // absl::btree_multiset<std::string> set7(v.begin(), v.end()); |
| btree_multiset() {} |
| using Base::Base; |
| |
| // btree_multiset::begin() |
| // |
| // Returns an iterator to the beginning of the `btree_multiset`. |
| using Base::begin; |
| |
| // btree_multiset::cbegin() |
| // |
| // Returns a const iterator to the beginning of the `btree_multiset`. |
| using Base::cbegin; |
| |
| // btree_multiset::end() |
| // |
| // Returns an iterator to the end of the `btree_multiset`. |
| using Base::end; |
| |
| // btree_multiset::cend() |
| // |
| // Returns a const iterator to the end of the `btree_multiset`. |
| using Base::cend; |
| |
| // btree_multiset::empty() |
| // |
| // Returns whether or not the `btree_multiset` is empty. |
| using Base::empty; |
| |
| // btree_multiset::max_size() |
| // |
| // Returns the largest theoretical possible number of elements within a |
| // `btree_multiset` under current memory constraints. This value can be |
| // thought of as the largest value of `std::distance(begin(), end())` for a |
| // `btree_multiset<Key>`. |
| using Base::max_size; |
| |
| // btree_multiset::size() |
| // |
| // Returns the number of elements currently within the `btree_multiset`. |
| using Base::size; |
| |
| // btree_multiset::clear() |
| // |
| // Removes all elements from the `btree_multiset`. Invalidates any references, |
| // pointers, or iterators referring to contained elements. |
| using Base::clear; |
| |
| // btree_multiset::erase() |
| // |
| // Erases elements within the `btree_multiset`. Overloads are listed below. |
| // |
| // iterator erase(iterator position): |
| // iterator erase(const_iterator position): |
| // |
| // Erases the element at `position` of the `btree_multiset`, returning |
| // the iterator pointing to the element after the one that was erased |
| // (or end() if none exists). |
| // |
| // iterator erase(const_iterator first, const_iterator last): |
| // |
| // Erases the elements in the open interval [`first`, `last`), returning |
| // the iterator pointing to the element after the interval that was erased |
| // (or end() if none exists). |
| // |
| // template <typename K> size_type erase(const K& key): |
| // |
| // Erases the elements matching the key, if any exist, returning the |
| // number of elements erased. |
| using Base::erase; |
| |
| // btree_multiset::insert() |
| // |
| // Inserts an element of the specified value into the `btree_multiset`, |
| // returning an iterator pointing to the newly inserted element. |
| // Any references, pointers, or iterators are invalidated. Overloads are |
| // listed below. |
| // |
| // iterator insert(const value_type& value): |
| // |
| // Inserts a value into the `btree_multiset`, returning an iterator to the |
| // inserted element. |
| // |
| // iterator insert(value_type&& value): |
| // |
| // Inserts a moveable value into the `btree_multiset`, returning an iterator |
| // to the inserted element. |
| // |
| // iterator insert(const_iterator hint, const value_type& value): |
| // iterator insert(const_iterator hint, value_type&& value): |
| // |
| // Inserts a value, using the position of `hint` as a non-binding suggestion |
| // for where to begin the insertion search. Returns an iterator to the |
| // inserted element. |
| // |
| // void insert(InputIterator first, InputIterator last): |
| // |
| // Inserts a range of values [`first`, `last`). |
| // |
| // void insert(std::initializer_list<init_type> ilist): |
| // |
| // Inserts the elements within the initializer list `ilist`. |
| using Base::insert; |
| |
| // btree_multiset::emplace() |
| // |
| // Inserts an element of the specified value by constructing it in-place |
| // within the `btree_multiset`. Any references, pointers, or iterators are |
| // invalidated. |
| using Base::emplace; |
| |
| // btree_multiset::emplace_hint() |
| // |
| // Inserts an element of the specified value by constructing it in-place |
| // within the `btree_multiset`, using the position of `hint` as a non-binding |
| // suggestion for where to begin the insertion search. |
| // |
| // Any references, pointers, or iterators are invalidated. |
| using Base::emplace_hint; |
| |
| // btree_multiset::extract() |
| // |
| // Extracts the indicated element, erasing it in the process, and returns it |
| // as a C++17-compatible node handle. Overloads are listed below. |
| // |
| // node_type extract(const_iterator position): |
| // |
| // Extracts the element at the indicated position and returns a node handle |
| // owning that extracted data. |
| // |
| // template <typename K> node_type extract(const K& k): |
| // |
| // Extracts the element with the key matching the passed key value and |
| // returns a node handle owning that extracted data. If the `btree_multiset` |
| // does not contain an element with a matching key, this function returns an |
| // empty node handle. |
| // |
| // NOTE: In this context, `node_type` refers to the C++17 concept of a |
| // move-only type that owns and provides access to the elements in associative |
| // containers (https://en.cppreference.com/w/cpp/container/node_handle). |
| // It does NOT refer to the data layout of the underlying btree. |
| using Base::extract; |
| |
| // btree_multiset::merge() |
| // |
| // Extracts all elements from a given `source` btree_multiset into this |
| // `btree_multiset`. |
| using Base::merge; |
| |
| // btree_multiset::swap(btree_multiset& other) |
| // |
| // Exchanges the contents of this `btree_multiset` with those of the `other` |
| // btree_multiset, avoiding invocation of any move, copy, or swap operations |
| // on individual elements. |
| // |
| // All iterators and references on the `btree_multiset` remain valid, |
| // excepting for the past-the-end iterator, which is invalidated. |
| using Base::swap; |
| |
| // btree_multiset::contains() |
| // |
| // template <typename K> bool contains(const K& key) const: |
| // |
| // Determines whether an element comparing equal to the given `key` exists |
| // within the `btree_multiset`, returning `true` if so or `false` otherwise. |
| // |
| // Supports heterogeneous lookup, provided that the set has a compatible |
| // heterogeneous comparator. |
| using Base::contains; |
| |
| // btree_multiset::count() |
| // |
| // template <typename K> size_type count(const K& key) const: |
| // |
| // Returns the number of elements comparing equal to the given `key` within |
| // the `btree_multiset`. |
| // |
| // Supports heterogeneous lookup, provided that the set has a compatible |
| // heterogeneous comparator. |
| using Base::count; |
| |
| // btree_multiset::equal_range() |
| // |
| // Returns a closed range [first, last], defined by a `std::pair` of two |
| // iterators, containing all elements with the passed key in the |
| // `btree_multiset`. |
| using Base::equal_range; |
| |
| // btree_multiset::find() |
| // |
| // template <typename K> iterator find(const K& key): |
| // template <typename K> const_iterator find(const K& key) const: |
| // |
| // Finds an element with the passed `key` within the `btree_multiset`. |
| // |
| // Supports heterogeneous lookup, provided that the set has a compatible |
| // heterogeneous comparator. |
| using Base::find; |
| |
| // btree_multiset::lower_bound() |
| // |
| // template <typename K> iterator lower_bound(const K& key): |
| // template <typename K> const_iterator lower_bound(const K& key) const: |
| // |
| // Finds the first element that is not less than `key` within the |
| // `btree_multiset`. |
| // |
| // Supports heterogeneous lookup, provided that the set has a compatible |
| // heterogeneous comparator. |
| using Base::lower_bound; |
| |
| // btree_multiset::upper_bound() |
| // |
| // template <typename K> iterator upper_bound(const K& key): |
| // template <typename K> const_iterator upper_bound(const K& key) const: |
| // |
| // Finds the first element that is greater than `key` within the |
| // `btree_multiset`. |
| // |
| // Supports heterogeneous lookup, provided that the set has a compatible |
| // heterogeneous comparator. |
| using Base::upper_bound; |
| |
| // btree_multiset::get_allocator() |
| // |
| // Returns the allocator function associated with this `btree_multiset`. |
| using Base::get_allocator; |
| |
| // btree_multiset::key_comp(); |
| // |
| // Returns the key comparator associated with this `btree_multiset`. |
| using Base::key_comp; |
| |
| // btree_multiset::value_comp(); |
| // |
| // Returns the value comparator associated with this `btree_multiset`. The |
| // keys to sort the elements are the values themselves, therefore `value_comp` |
| // and its sibling member function `key_comp` are equivalent. |
| using Base::value_comp; |
| }; |
| |
| // absl::swap(absl::btree_multiset<>, absl::btree_multiset<>) |
| // |
| // Swaps the contents of two `absl::btree_multiset` containers. |
| template <typename K, typename C, typename A> |
| void swap(btree_multiset<K, C, A> &x, btree_multiset<K, C, A> &y) { |
| return x.swap(y); |
| } |
| |
| // absl::erase_if(absl::btree_multiset<>, Pred) |
| // |
| // Erases all elements that satisfy the predicate pred from the container. |
| // Returns the number of erased elements. |
| template <typename K, typename C, typename A, typename Pred> |
| typename btree_multiset<K, C, A>::size_type erase_if( |
| btree_multiset<K, C, A> & set, Pred pred) { |
| return container_internal::btree_access::erase_if(set, std::move(pred)); |
| } |
| |
| namespace container_internal { |
| |
| // This type implements the necessary functions from the |
| // absl::container_internal::slot_type interface for btree_(multi)set. |
| template <typename Key> |
| struct set_slot_policy { |
| using slot_type = Key; |
| using value_type = Key; |
| using mutable_value_type = Key; |
| |
| static value_type &element(slot_type *slot) { return *slot; } |
| static const value_type &element(const slot_type *slot) { return *slot; } |
| |
| template <typename Alloc, class... Args> |
| static void construct(Alloc *alloc, slot_type *slot, Args &&...args) { |
| absl::allocator_traits<Alloc>::construct(*alloc, slot, |
| std::forward<Args>(args)...); |
| } |
| |
| template <typename Alloc> |
| static void construct(Alloc *alloc, slot_type *slot, slot_type *other) { |
| absl::allocator_traits<Alloc>::construct(*alloc, slot, std::move(*other)); |
| } |
| |
| template <typename Alloc> |
| static void construct(Alloc *alloc, slot_type *slot, const slot_type *other) { |
| absl::allocator_traits<Alloc>::construct(*alloc, slot, *other); |
| } |
| |
| template <typename Alloc> |
| static void destroy(Alloc *alloc, slot_type *slot) { |
| absl::allocator_traits<Alloc>::destroy(*alloc, slot); |
| } |
| |
| template <typename Alloc> |
| static void transfer(Alloc *alloc, slot_type *new_slot, slot_type *old_slot) { |
| construct(alloc, new_slot, old_slot); |
| destroy(alloc, old_slot); |
| } |
| }; |
| |
| // A parameters structure for holding the type parameters for a btree_set. |
| // Compare and Alloc should be nothrow copy-constructible. |
| template <typename Key, typename Compare, typename Alloc, int TargetNodeSize, |
| bool IsMulti> |
| struct set_params : common_params<Key, Compare, Alloc, TargetNodeSize, IsMulti, |
| /*IsMap=*/false, set_slot_policy<Key>> { |
| using value_type = Key; |
| using slot_type = typename set_params::common_params::slot_type; |
| |
| template <typename V> |
| static const V &key(const V &value) { |
| return value; |
| } |
| static const Key &key(const slot_type *slot) { return *slot; } |
| static const Key &key(slot_type *slot) { return *slot; } |
| }; |
| |
| } // namespace container_internal |
| |
| ABSL_NAMESPACE_END |
| } // namespace absl |
| |
| #endif // ABSL_CONTAINER_BTREE_SET_H_ |