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std::list<T,Allocator>::push_front

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< cpp‎ | container‎ | list
 
 
Containers library
Sequence
(C++11)
Associative
Unordered associative
Adaptors
Views
(C++20)
 
 
void push_front( const T& value );
void push_front( T&& value );
(since C++11)

Prepends the given element value to the beginning of the container.

No iterators or references are invalidated.

Contents

[edit] Parameters

value - the value of the element to prepend

[edit] Return value

(none)

[edit] Complexity

Constant.

[edit] Exceptions

If an exception is thrown, this function has no effect (strong exception guarantee).

[edit] Example

#include <list>
#include <iostream>
#include <iomanip>
#include <string>
 
int main()
{
    std::list<std::string> letters;
 
    letters.push_front("abc");
    std::string s{"def"};
    letters.push_front(std::move(s));
 
    std::cout << "std::list `letters` holds: ";
    for (auto&& e : letters) std::cout << std::quoted(e) << ' ';
 
    std::cout << "\nMoved-from string `s` holds: " << std::quoted(s) << '\n';
}

Possible output:

std::list `letters` holds: "def" "abc" 
Moved-from string `s` holds: ""

[edit] See also

constructs an element in-place at the beginning
(public member function) [edit]
adds an element to the end
(public member function) [edit]
removes the first element
(public member function) [edit]
creates a std::front_insert_iterator of type inferred from the argument
(function template) [edit]