Standard library header <vector>
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C++
Feature test macros (C++20)
Concepts library (C++20)
Metaprogramming library (C++11)
Ranges library (C++20)
Filesystem library (C++17)
Concurrency support library (C++11)
Execution control library (C++26)
Standard library headers
<compare> (C++20)
<contracts> (C++26)
<coroutine> (C++20)
<cstdint> (C++11)
<source_location> (C++20)
<stdfloat> (C++23)
<version> (C++20)
<concepts> (C++20)
<debugging> (C++26)
<stacktrace> (C++23)
<system_error> (C++11)
<memory_resource> (C++17)
<scoped_allocator> (C++11)
<type_traits> (C++11)
<ratio> (C++11)
<any> (C++17)
<bit> (C++20)
<charconv> (C++17)
<expected> (C++23)
<format> (C++20)
<optional> (C++17)
<stdbit.h> (C++26)
<tuple> (C++11)
<typeindex> (C++11)
<variant> (C++17)
<array> (C++11)
<flat_map> (C++23)
<flat_set> (C++23)
<forward_list> (C++11)
<hive> (C++26)
<mdspan> (C++23)
<span> (C++20)
<unordered_map> (C++11)
<unordered_set> (C++11)
<vector>
<generator> (C++23)
<ranges> (C++20)
<cuchar> (C++11)
<string_view> (C++17)
<codecvt> (C++11/17/26*)
<regex> (C++11)
<cfenv> (C++11)
<linalg> (C++26)
<numbers> (C++20)
<random> (C++11)
<simd> (C++26)
<stdckdint.h> (C++26)
<chrono> (C++11)
<ccomplex> (C++11/17/20*)
<ciso646> (until C++20)
<cstdalign> (C++11/17/20*)
<cstdbool> (C++11/17/20*)
<ctgmath> (C++11/17/20*)
<cinttypes> (C++11)
<filesystem> (C++17)
<print> (C++23)
<spanstream> (C++23)
<strstream> (C++98/26*)
<syncstream> (C++20)
<atomic> (C++11)
<barrier> (C++20)
<condition_variable> (C++11)
<future> (C++11)
<hazard_pointer> (C++26)
<latch> (C++20)
<mutex> (C++11)
<rcu> (C++26)
<semaphore> (C++20)
<shared_mutex> (C++14)
<stdatomic.h> (C++23)
<stop_token> (C++20)
<thread> (C++11)
<execution> (C++17)
This header is part of the containers library.
Contents
Includes
(C++20)
(C++11)
Classes
(class template) [edit]
(class template specialization) [edit]
(C++11)
(class template specialization)
Forward declarations
Defined in header
<functional> (C++11)
(class template) [edit]
Functions
(removed in C++20)(removed in C++20)(removed in C++20)(removed in C++20)(removed in C++20)(C++20)
vectors (function template) [edit]
(function template) [edit]
(function template) [edit]
Range access
(C++11)(C++14)
(function template) [edit]
(C++11)(C++14)
(function template) [edit]
(C++14)
(function template) [edit]
(C++14)
(function template) [edit]
(C++17)(C++20)
(function template) [edit]
(C++17)
(function template) [edit]
(C++17)
(function template) [edit]
[edit] Synopsis
#include <compare> #include <initializer_list> namespace std { // class template vector template<class T, class Allocator = allocator<T>> class vector; template<class T, class Allocator> constexpr bool operator==(const vector<T, Allocator>& x, const vector<T, Allocator>& y); template<class T, class Allocator> constexpr /*synth-three-way-result*/<T> operator<=>(const vector<T, Allocator>& x, const vector<T, Allocator>& y); template<class T, class Allocator> constexpr void swap(vector<T, Allocator>& x, vector<T, Allocator>& y) noexcept(noexcept(x.swap(y))); // erasure template<class T, class Allocator, class U = T> constexpr typename vector<T, Allocator>::size_type erase(vector<T, Allocator>& c, const U& value); template<class T, class Allocator, class Predicate> constexpr typename vector<T, Allocator>::size_type erase_if(vector<T, Allocator>& c, Predicate pred); namespace pmr { template<class T> using vector = std::vector <T, polymorphic_allocator<T>>; } // specialization of vector for bool // partial class template specialization vector<bool, Allocator> template<class Allocator> class vector<bool, Allocator>; template<class T> constexpr bool /*is-vector-bool-reference*/ = /* see description */; // exposition only // hash support template<class T> struct hash; template<class Allocator> struct hash<vector<bool, Allocator>>; // formatter specialization for vector<bool> template<class T, class CharT> requires /*is-vector-bool-reference*/<T> struct formatter<T, CharT>; }
[edit] Class template std::vector
namespace std { template<class T, class Allocator = allocator<T>> class vector { 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 */; using difference_type = /* implementation-defined */; using iterator = /* implementation-defined */; using const_iterator = /* implementation-defined */; using reverse_iterator = std::reverse_iterator <iterator>; using const_reverse_iterator = std::reverse_iterator <const_iterator>; // construct/copy/destroy constexpr vector() noexcept(noexcept(Allocator())) : vector(Allocator()) { } constexpr explicit vector(const Allocator&) noexcept; constexpr explicit vector(size_type n, const Allocator& = Allocator()); constexpr vector(size_type n, const T& value, const Allocator& = Allocator()); template<class InputIter> constexpr vector(InputIter first, InputIter last, const Allocator& = Allocator()); template<container-compatible-range <T> R> constexpr vector(from_range_t, R&& rg, const Allocator& = Allocator()); constexpr vector(const vector& x); constexpr vector(vector&&) noexcept; constexpr vector(const vector&, const type_identity_t<Allocator>&); constexpr vector(vector&&, const type_identity_t<Allocator>&); constexpr vector(initializer_list<T>, const Allocator& = Allocator()); constexpr ~vector(); constexpr vector& operator=(const vector& x); constexpr vector& operator=(vector&& x) noexcept( allocator_traits<Allocator>::propagate_on_container_move_assignment::value || allocator_traits<Allocator>::is_always_equal::value); constexpr vector& operator=(initializer_list<T>); template<class InputIter> constexpr void assign(InputIter first, InputIter last); template<container-compatible-range <T> R> constexpr void assign_range(R&& rg); constexpr void assign(size_type n, const T& u); constexpr void assign(initializer_list<T>); constexpr allocator_type get_allocator() const noexcept; // iterators constexpr iterator begin() noexcept; constexpr const_iterator begin() const noexcept; constexpr iterator end() noexcept; constexpr const_iterator end() const noexcept; constexpr reverse_iterator rbegin() noexcept; constexpr const_reverse_iterator rbegin() const noexcept; constexpr reverse_iterator rend() noexcept; constexpr const_reverse_iterator rend() const noexcept; constexpr const_iterator cbegin() const noexcept; constexpr const_iterator cend() const noexcept; constexpr const_reverse_iterator crbegin() const noexcept; constexpr const_reverse_iterator crend() const noexcept; // capacity constexpr bool empty() const noexcept; constexpr size_type size() const noexcept; constexpr size_type max_size() const noexcept; constexpr size_type capacity() const noexcept; constexpr void resize(size_type sz); constexpr void resize(size_type sz, const T& c); constexpr void reserve(size_type n); constexpr void shrink_to_fit(); // element access constexpr reference operator[](size_type n); constexpr const_reference operator[](size_type n) const; constexpr const_reference at(size_type n) const; constexpr reference at(size_type n); constexpr reference front(); constexpr const_reference front() const; constexpr reference back(); constexpr const_reference back() const; // data access constexpr T* data() noexcept; constexpr const T* data() const noexcept; // modifiers template<class... Args> constexpr reference emplace_back(Args&&... args); constexpr void push_back(const T& x); constexpr void push_back(T&& x); template<container-compatible-range <T> R> constexpr void append_range(R&& rg); constexpr void pop_back(); template<class... Args> constexpr iterator emplace(const_iterator position, Args&&... args); constexpr iterator insert(const_iterator position, const T& x); constexpr iterator insert(const_iterator position, T&& x); constexpr iterator insert(const_iterator position, size_type n, const T& x); template<class InputIter> constexpr iterator insert(const_iterator position, InputIter first, InputIter last); template<container-compatible-range <T> R> constexpr iterator insert_range(const_iterator position, R&& rg); constexpr iterator insert(const_iterator position, initializer_list<T> il); constexpr iterator erase(const_iterator position); constexpr iterator erase(const_iterator first, const_iterator last); constexpr void swap(vector&) noexcept( allocator_traits<Allocator>::propagate_on_container_swap::value || allocator_traits<Allocator>::is_always_equal::value); constexpr void clear() noexcept; }; template<class InputIter, class Allocator = allocator</*iter-value-type*/<InputIter>>> vector(InputIter, InputIter, Allocator = Allocator()) -> vector</*iter-value-type*/<InputIter>, Allocator>; template<ranges::input_range R, class Allocator = allocator<ranges::range_value_t <R>>> vector(from_range_t, R&&, Allocator = Allocator()) -> vector<ranges::range_value_t <R>, Allocator>; }
[edit] Class template std::vector specialization for bool
namespace std { template<class Allocator> class vector<bool, Allocator> { public: // types using value_type = bool; using allocator_type = Allocator; using pointer = /* implementation-defined */; using const_pointer = /* implementation-defined */; using const_reference = bool; using size_type = /* implementation-defined */; using difference_type = /* implementation-defined */; using iterator = /* implementation-defined */; using const_iterator = /* implementation-defined */; using reverse_iterator = std::reverse_iterator <iterator>; using const_reverse_iterator = std::reverse_iterator <const_iterator>; // bit reference class reference { public: constexpr reference(const reference&) = default; constexpr ~reference(); constexpr operator bool() const noexcept; constexpr reference& operator=(bool x) noexcept; constexpr reference& operator=(const reference& x) noexcept; constexpr const reference& operator=(bool x) const noexcept; constexpr void flip() noexcept; // flips the bit }; // construct/copy/destroy constexpr vector() noexcept(noexcept(Allocator())) : vector(Allocator()) { } constexpr explicit vector(const Allocator&) noexcept; constexpr explicit vector(size_type n, const Allocator& = Allocator()); constexpr vector(size_type n, const bool& value, const Allocator& = Allocator()); template<class InputIter> constexpr vector(InputIter first, InputIter last, const Allocator& = Allocator()); template<container-compatible-range <bool> R> constexpr vector(from_range_t, R&& rg, const Allocator& = Allocator()); constexpr vector(const vector& x); constexpr vector(vector&& x) noexcept; constexpr vector(const vector&, const type_identity_t<Allocator>&); constexpr vector(vector&&, const type_identity_t<Allocator>&); constexpr vector(initializer_list<bool>, const Allocator& = Allocator()); constexpr ~vector(); constexpr vector& operator=(const vector& x); constexpr vector& operator=(vector&& x) noexcept( allocator_traits<Allocator>::propagate_on_container_move_assignment::value || allocator_traits<Allocator>::is_always_equal::value); constexpr vector& operator=(initializer_list<bool>); template<class InputIter> constexpr void assign(InputIter first, InputIter last); template<container-compatible-range <bool> R> constexpr void assign_range(R&& rg); constexpr void assign(size_type n, const bool& t); constexpr void assign(initializer_list<bool>); constexpr allocator_type get_allocator() const noexcept; // iterators constexpr iterator begin() noexcept; constexpr const_iterator begin() const noexcept; constexpr iterator end() noexcept; constexpr const_iterator end() const noexcept; constexpr reverse_iterator rbegin() noexcept; constexpr const_reverse_iterator rbegin() const noexcept; constexpr reverse_iterator rend() noexcept; constexpr const_reverse_iterator rend() const noexcept; constexpr const_iterator cbegin() const noexcept; constexpr const_iterator cend() const noexcept; constexpr const_reverse_iterator crbegin() const noexcept; constexpr const_reverse_iterator crend() const noexcept; // capacity constexpr bool empty() const noexcept; constexpr size_type size() const noexcept; constexpr size_type max_size() const noexcept; constexpr size_type capacity() const noexcept; constexpr void resize(size_type sz, bool c = false); constexpr void reserve(size_type n); constexpr void shrink_to_fit(); // element access constexpr reference operator[](size_type n); constexpr const_reference operator[](size_type n) const; constexpr const_reference at(size_type n) const; constexpr reference at(size_type n); constexpr reference front(); constexpr const_reference front() const; constexpr reference back(); constexpr const_reference back() const; // modifiers template<class... Args> constexpr reference emplace_back(Args&&... args); constexpr void push_back(const bool& x); template<container-compatible-range <bool> R> constexpr void append_range(R&& rg); constexpr void pop_back(); template<class... Args> constexpr iterator emplace(const_iterator position, Args&&... args); constexpr iterator insert(const_iterator position, const bool& x); constexpr iterator insert(const_iterator position, size_type n, const bool& x); template<class InputIter> constexpr iterator insert(const_iterator position, InputIter first, InputIter last); template<container-compatible-range <bool> R> constexpr iterator insert_range(const_iterator position, R&& rg); constexpr iterator insert(const_iterator position, initializer_list<bool> il); constexpr iterator erase(const_iterator position); constexpr iterator erase(const_iterator first, const_iterator last); constexpr void swap(vector&) noexcept( allocator_traits<Allocator>::propagate_on_container_swap::value || allocator_traits<Allocator>::is_always_equal::value); static constexpr void swap(reference x, reference y) noexcept; constexpr void flip() noexcept; // flips all bits constexpr void clear() noexcept; }; }
[edit] Class template std::formatter specialization for std::vector <bool>::reference
namespace std { template<class T, class CharT> requires /*is-vector-bool-reference*/<T> struct formatter<T, CharT> { private: formatter<bool, CharT> /*underlying_*/; // exposition only public: template<class ParseContext> constexpr typename ParseContext::iterator parse(ParseContext& ctx); template<class FormatContext> typename FormatContext::iterator format(const T& ref, FormatContext& ctx) const; }; }
[edit] Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
| DR | Applied to | Behavior as published | Correct behavior |
|---|---|---|---|
| LWG 4140 | C++98 | the synopsis contains a declaration of the default constructor of std::vector <bool, Alloc>::reference |
removed the declaration |