std::list

 

C++

Compiler support

Freestanding and hosted

Language

Standard library

Standard library headers

Named requirements

Feature test macros (C++20)

Language support library

Concepts library (C++20)

Metaprogramming library (C++11)

Diagnostics library

General utilities library

Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

Localizations library

Input/output library

Filesystem library (C++17)

Regular expressions library (C++11)

Concurrency support library (C++11)

Execution support library (C++26)

Technical specifications

Symbols index

External libraries

 

Containers library

Sequence

array (C++11)

vector

vector<bool>

inplace_vector (C++26)

deque

forward_list (C++11)

list

Associative

set

multiset

map

multimap

Unordered associative

unordered_set (C++11)

unordered_multiset (C++11)

unordered_map (C++11)

unordered_multimap (C++11)

Adaptors

stack

queue

priority_queue

flat_set (C++23)

flat_multiset (C++23)

flat_map (C++23)

flat_multimap (C++23)

Views

span (C++20)

mdspan (C++23)

Tables

Iterator invalidation

Member function table

Non-member function table

 

std::list

Member functions
list::list list::~list list::operator= list::assign list::assign_range (C++23)   list::get_allocator Element access list::front list::back Iterators list::beginlist::cbegin (C++11) list::endlist::cend (C++11) list::rbeginlist::crbegin (C++11) list::rendlist::crend (C++11) Capacity list::size list::empty list::max_size	Modifiers list::clear list::insert list::insert_range (C++23) list::emplace (C++11) list::erase list::push_front list::emplace_front (C++11) list::prepend_range (C++23) list::pop_front list::push_back list::emplace_back (C++11) list::append_range (C++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<=> (C++20) swap(std::list) erase(std::list)erase_if(std::list) (C++20)(C++20)	operator!=operator<operator>operator<=operator>= (until C++20)(until C++20)(until C++20)(until C++20)(until C++20)
Deduction guides(C++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 C++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 C++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 C++11) (until C++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 (C++17) Minimal incomplete type support (since C++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 C++20)The program is ill-formed(since C++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 C++11) std::allocator_traits<Allocator>::pointer (since C++11)
const_pointer	Allocator::const_pointer (until C++11) std::allocator_traits<Allocator>::const_pointer (since C++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 (C++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 (C++11)	returns an iterator to the beginning (public member function)
endcend (C++11)	returns an iterator to the end (public member function)
rbegincrbegin (C++11)	returns a reverse iterator to the beginning (public member function)
rendcrend (C++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 (C++23)	inserts a range of elements (public member function)
emplace (C++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 (C++11)	constructs an element in-place at the end (public member function)
append_range (C++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 (C++11)	constructs an element in-place at the beginning (public member function)
prepend_range (C++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 C++20)(removed in C++20)(removed in C++20)(removed in C++20)(removed in C++20)(C++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) (C++20)	erases all elements satisfying specific criteria (function template)

Deduction guides

(since C++17)

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 C++ standards.

DR	Applied to	Behavior as published	Correct behavior
LWG 230	C++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	C++98	T was always required to be CopyAssignable	only required if operator= or assign is instantiated with T