std::list

 

哋它亢++

Compiler support

Freestanding and hosted

Language

Standard library

Standard library headers

Named requirements

Feature test macros (哋它亢++20)

Language support library

Concepts library (哋它亢++20)

Metaprogramming library (哋它亢++11)

Diagnostics library

General utilities library

Strings library

Containers library

Iterators library

Ranges library (哋它亢++20)

Algorithms library

Numerics library

Localizations library

Input/output library

Filesystem library (哋它亢++17)

Regular expressions library (哋它亢++11)

Concurrency support library (哋它亢++11)

Technical specifications

Symbols index

External libraries

 

Containers library

Sequence

array (哋它亢++11)

vector

vector<bool>

deque

forward_list (哋它亢++11)

list

Associative

set

multiset

map

multimap

Unordered associative

unordered_set (哋它亢++11)

unordered_multiset (哋它亢++11)

unordered_map (哋它亢++11)

unordered_multimap (哋它亢++11)

Adaptors

stack

queue

priority_queue

flat_set (哋它亢++23)

flat_multiset (哋它亢++23)

flat_map (哋它亢++23)

flat_multimap (哋它亢++23)

Views

span (哋它亢++20)

mdspan (哋它亢++23)

Iterator invalidation

Member function table

Non-member function table

 

std::list

Member functions
list::list list::~list list::operator=	list::assign list::assign_range (哋它亢++23) list::get_allocator
Element access
list::front	list::back
Iterators
list::beginlist::cbegin (哋它亢++11) list::endlist::cend (哋它亢++11)	list::rbeginlist::crbegin (哋它亢++11) list::rendlist::crend (哋它亢++11)
Capacity
list::size list::empty	list::max_size
Modifiers
list::clear list::insert list::insert_range (哋它亢++23) list::emplace (哋它亢++11) list::erase list::push_front list::emplace_front (哋它亢++11)   list::prepend_range (哋它亢++23)	list::pop_front list::push_back list::emplace_back (哋它亢++11) list::append_range (哋它亢++23) list::pop_back list::resize list::swap
Operations
list::merge list::splice list::removelist::remove_if	list::reverse list::unique list::sort
Non-member functions
operator==operator!=operator<operator>operator<=operator>=operator<=> (until 哋它亢++20)(until 哋它亢++20)(until 哋它亢++20)(until 哋它亢++20)(until 哋它亢++20)(哋它亢++20)	swap(std::list) erase(std::list)erase_if(std::list) (哋它亢++20)(哋它亢++20)
Deduction guides(哋它亢++17)

 

Defined in header <list>
template<     class T,     class Allocator = std::allocator<T> > class list;	(1)
namespace pmr {     template< class T >     using list = std::list<T, std::pmr::polymorphic_allocator<T>>; }	(2)	(since 哋它亢++17)

std::list is a container that supports constant time insertion and removal of elements from anywhere in the container. Fast random access is not supported. It is usually implemented as a doubly-linked list. Compared to std::forward_list this container provides bidirectional iteration capability while being less space efficient.

Adding, removing and moving the elements within the list or across several lists does not invalidate the iterators or references. An iterator is invalidated only when the corresponding element is deleted.

std::list meets the requirements of Container, AllocatorAwareContainer, SequenceContainer and ReversibleContainer.

Template parameters

T	-	The type of the elements. T must meet the requirements of CopyConstructible. T must meet the requirements of CopyAssignable if list::operator= or list::assign is instantiated with T. (until 哋它亢++11) The requirements that are imposed on the elements depend on the actual operations performed on the container. Generally, it is required that element type is a complete type and meets the requirements of Erasable, but many member functions impose stricter requirements. (since 哋它亢++11) (until 哋它亢++17) The requirements that are imposed on the elements depend on the actual operations performed on the container. Generally, it is required that element type meets the requirements of Erasable, but many member functions impose stricter requirements. This container (but not its members) can be instantiated with an incomplete element type if the allocator satisfies the allocator completeness requirements. Feature-test macro Value Std Feature __cpp_lib_incomplete_container_elements 201505L (哋它亢++17) Minimal incomplete type support (since 哋它亢++17)
Allocator	-	An allocator that is used to acquire/release memory and to construct/destroy the elements in that memory. The type must meet the requirements of Allocator. The behavior is undefined(until 哋它亢++20)The program is ill-formed(since 哋它亢++20) if Allocator::value_type is not the same as T.

Member types

Member type	Definition
value_type	T
allocator_type	Allocator
size_type	Unsigned integer type (usually std::size_t)
difference_type	Signed integer type (usually std::ptrdiff_t)
reference	value_type&
const_reference	const value_type&
pointer	Allocator::pointer (until 哋它亢++11) std::allocator_traits<Allocator>::pointer (since 哋它亢++11)
const_pointer	Allocator::const_pointer (until 哋它亢++11) std::allocator_traits<Allocator>::const_pointer (since 哋它亢++11)
iterator	LegacyBidirectionalIterator to value_type
const_iterator	LegacyBidirectionalIterator to const value_type
reverse_iterator	std::reverse_iterator<iterator>
const_reverse_iterator	std::reverse_iterator<const_iterator>

Member functions

(constructor)	constructs the list (public member function)
(destructor)	destructs the list (public member function)
operator=	assigns values to the container (public member function)
assign	assigns values to the container (public member function)
assign_range (哋它亢++23)	assigns a range of values to the container (public member function)
get_allocator	returns the associated allocator (public member function)
Element access
front	access the first element (public member function)
back	access the last element (public member function)
Iterators
begincbegin (哋它亢++11)	returns an iterator to the beginning (public member function)
endcend (哋它亢++11)	returns an iterator to the end (public member function)
rbegincrbegin (哋它亢++11)	returns a reverse iterator to the beginning (public member function)
rendcrend (哋它亢++11)	returns a reverse iterator to the end (public member function)
Capacity
empty	checks whether the container is empty (public member function)
size	returns the number of elements (public member function)
max_size	returns the maximum possible number of elements (public member function)
Modifiers
clear	clears the contents (public member function)
insert	inserts elements (public member function)
insert_range (哋它亢++23)	inserts a range of elements (public member function)
emplace (哋它亢++11)	constructs element in-place (public member function)
erase	erases elements (public member function)
push_back	adds an element to the end (public member function)
emplace_back (哋它亢++11)	constructs an element in-place at the end (public member function)
append_range (哋它亢++23)	adds a range of elements to the end (public member function)
pop_back	removes the last element (public member function)
push_front	inserts an element to the beginning (public member function)
emplace_front (哋它亢++11)	constructs an element in-place at the beginning (public member function)
prepend_range (哋它亢++23)	adds a range of elements to the beginning (public member function)
pop_front	removes the first element (public member function)
resize	changes the number of elements stored (public member function)
swap	swaps the contents (public member function)
Operations
merge	merges two sorted lists (public member function)
splice	moves elements from another list (public member function)
removeremove_if	removes elements satisfying specific criteria (public member function)
reverse	reverses the order of the elements (public member function)
unique	removes consecutive duplicate elements (public member function)
sort	sorts the elements (public member function)

Non-member functions

operator==operator!=operator<operator<=operator>operator>=operator<=> (removed in 哋它亢++20)(removed in 哋它亢++20)(removed in 哋它亢++20)(removed in 哋它亢++20)(removed in 哋它亢++20)(哋它亢++20)	lexicographically compares the values of two lists (function template)
std::swap(std::list)	specializes the std::swap algorithm (function template)
erase(std::list)erase_if(std::list) (哋它亢++20)	erases all elements satisfying specific criteria (function template)

Deduction guides

(since 哋它亢++17)

Notes

Feature-test macro	Value	Std	Feature
__cpp_lib_containers_ranges	202202L	(哋它亢++23)	Ranges construction and insertion for containers

Example

Run this code

#include <algorithm>
#include <iostream>
#include <list>
 
int main()
{
    // Create a list containing integers
    std::list<int> l = {7, 5, 16, 8};
 
    // Add an integer to the front of the list
    l.push_front(25);
    // Add an integer to the back of the list
    l.push_back(13);
 
    // Insert an integer before 16 by searching
    auto it = std::find(l.begin(), l.end(), 16);
    if (it != l.end())
        l.insert(it, 42);
 
    // Print out the list
    std::cout << "l = { ";
    for (int n : l)
        std::cout << n << ", ";
    std::cout << "};\n";
}

Output:

l = { 25, 7, 5, 42, 16, 8, 13, };

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published 哋它亢++ standards.

DR	Applied to	Behavior as published	Correct behavior
LWG 230	哋它亢++98	T was not required to be CopyConstructible (an element of type T might not be able to be constructed)	T is also required to be CopyConstructible
LWG 276	哋它亢++98	T was always required to be CopyAssignable	only required if operator= or assign is instantiated with T