24 Containers library [containers]

24.3 Sequence containers [sequences]

24.3.10 Class template list [list] Overview [list.overview]

A list is a sequence container that supports bidirectional iterators and allows constant time insert and erase operations anywhere within the sequence, with storage management handled automatically.
Unlike vectors and deques, fast random access to list elements is not supported, but many algorithms only need sequential access anyway.
A list meets all of the requirements of a container ([container.reqmts]), of a reversible container ([container.rev.reqmts]), of an allocator-aware container ([container.alloc.reqmts]), and of a sequence container, including most of the optional sequence container requirements ([sequence.reqmts]).
The exceptions are the operator[] and at member functions, which are not provided.205
Descriptions are provided here only for operations on list that are not described in one of these tables or for operations where there is additional semantic information.
namespace std { template<class T, class Allocator = allocator<T>> class list { public: // types using value_type = T; using allocator_type = Allocator; using pointer = typename allocator_traits<Allocator>::pointer; using const_pointer = typename allocator_traits<Allocator>::const_pointer; using reference = value_type&; using const_reference = const value_type&; using size_type = implementation-defined; // see [container.requirements] using difference_type = implementation-defined; // see [container.requirements] using iterator = implementation-defined; // see [container.requirements] using const_iterator = implementation-defined; // see [container.requirements] using reverse_iterator = std::reverse_iterator<iterator>; using const_reverse_iterator = std::reverse_iterator<const_iterator>; // [list.cons], construct/copy/destroy list() : list(Allocator()) { } explicit list(const Allocator&); explicit list(size_type n, const Allocator& = Allocator()); list(size_type n, const T& value, const Allocator& = Allocator()); template<class InputIterator> list(InputIterator first, InputIterator last, const Allocator& = Allocator()); template<container-compatible-range<T> R> list(from_range_t, R&& rg, const Allocator& = Allocator()); list(const list& x); list(list&& x); list(const list&, const type_identity_t<Allocator>&); list(list&&, const type_identity_t<Allocator>&); list(initializer_list<T>, const Allocator& = Allocator()); ~list(); list& operator=(const list& x); list& operator=(list&& x) noexcept(allocator_traits<Allocator>::is_always_equal::value); list& operator=(initializer_list<T>); template<class InputIterator> void assign(InputIterator first, InputIterator last); template<container-compatible-range<T> R> void assign_range(R&& rg); void assign(size_type n, const T& t); void assign(initializer_list<T>); allocator_type get_allocator() const noexcept; // iterators iterator begin() noexcept; const_iterator begin() const noexcept; iterator end() noexcept; const_iterator end() const noexcept; reverse_iterator rbegin() noexcept; const_reverse_iterator rbegin() const noexcept; reverse_iterator rend() noexcept; const_reverse_iterator rend() const noexcept; const_iterator cbegin() const noexcept; const_iterator cend() const noexcept; const_reverse_iterator crbegin() const noexcept; const_reverse_iterator crend() const noexcept; // [list.capacity], capacity [[nodiscard]] bool empty() const noexcept; size_type size() const noexcept; size_type max_size() const noexcept; void resize(size_type sz); void resize(size_type sz, const T& c); // element access reference front(); const_reference front() const; reference back(); const_reference back() const; // [list.modifiers], modifiers template<class... Args> reference emplace_front(Args&&... args); template<class... Args> reference emplace_back(Args&&... args); void push_front(const T& x); void push_front(T&& x); template<container-compatible-range<T> R> void prepend_range(R&& rg); void pop_front(); void push_back(const T& x); void push_back(T&& x); template<container-compatible-range<T> R> void append_range(R&& rg); void pop_back(); template<class... Args> iterator emplace(const_iterator position, Args&&... args); iterator insert(const_iterator position, const T& x); iterator insert(const_iterator position, T&& x); iterator insert(const_iterator position, size_type n, const T& x); template<class InputIterator> iterator insert(const_iterator position, InputIterator first, InputIterator last); template<container-compatible-range<T> R> iterator insert_range(const_iterator position, R&& rg); iterator insert(const_iterator position, initializer_list<T> il); iterator erase(const_iterator position); iterator erase(const_iterator position, const_iterator last); void swap(list&) noexcept(allocator_traits<Allocator>::is_always_equal::value); void clear() noexcept; // [list.ops], list operations void splice(const_iterator position, list& x); void splice(const_iterator position, list&& x); void splice(const_iterator position, list& x, const_iterator i); void splice(const_iterator position, list&& x, const_iterator i); void splice(const_iterator position, list& x, const_iterator first, const_iterator last); void splice(const_iterator position, list&& x, const_iterator first, const_iterator last); size_type remove(const T& value); template<class Predicate> size_type remove_if(Predicate pred); size_type unique(); template<class BinaryPredicate> size_type unique(BinaryPredicate binary_pred); void merge(list& x); void merge(list&& x); template<class Compare> void merge(list& x, Compare comp); template<class Compare> void merge(list&& x, Compare comp); void sort(); template<class Compare> void sort(Compare comp); void reverse() noexcept; }; template<class InputIterator, class Allocator = allocator<iter-value-type<InputIterator>>> list(InputIterator, InputIterator, Allocator = Allocator()) -> list<iter-value-type<InputIterator>, Allocator>; template<ranges::input_range R, class Allocator = allocator<ranges::range_value_t<R>>> list(from_range_t, R&&, Allocator = Allocator()) -> list<ranges::range_value_t<R>, Allocator>; }
An incomplete type T may be used when instantiating list if the allocator meets the allocator completeness requirements.
T shall be complete before any member of the resulting specialization of list is referenced.
These member functions are only provided by containers whose iterators are random access iterators.