std::list::front

 

C++

Language

Standard library headers

Concepts

Utilities library

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Regular expressions library (C++11)

Atomic operations library (C++11)

Thread support library (C++11)

 

Containers library

array (C++11)

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std::list

Member functions

list::list

list::~list

list::operator=

list::assign

list::get_allocator

Element access

list::front

list::back

Iterators

list::begin list::cbegin (C++11)

list::end list::cend (C++11)

list::rbegin list::crbegin (C++11)

list::rend list::crend (C++11)

Capacity

list::empty

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Modifiers

list::clear

list::insert

list::emplace (C++11)

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list::push_front

list::emplace_front (C++11)

list::pop_front

list::push_back

list::emplace_back (C++11)

list::pop_back

list::resize

list::swap

Operations

list::merge

list::splice

list::remove list::remove_if

list::reverse

list::unique

list::sort

 

reference front();
const_reference front() const;

Returns a reference to the first element in the container.

Calling front on an empty container is undefined.

Parameters

(none)

Return value

reference to the first element

Complexity

Constant

Notes

For a container c, the expression c.front() is equivalent to *c.begin().

Example

The following code uses front to display the first element of a std::list<char>:

run this code

#include <list>
#include <iostream>
 
int main()
{
    std::list<char> letters {'o', 'm', 'g', 'w', 't', 'f'};
 
    if (!letters.empty()) {
        std::cout << "The first character is: " << letters.front() << '\n';
    }  
}

Output:

The first character is o

See also

back	access the last element (public member function)