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

void push_front( const T& value );
(1) (since C++11)
void push_front( T&& value );
(2) (since C++11)

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

No iterators or references are invalidated.

Parameters

value - the value of the element to prepend

Return value

(none).

Complexity

Constant.

Exceptions

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

Example

#include <forward_list>
#include <iomanip>
#include <iostream>
#include <string>
 
int main()
{
    std::forward_list<std::string> letters;
 
    letters.push_front("abc");
    std::string s{"def"};
    letters.push_front(std::move(s));
 
    std::cout << "std::forward_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::forward_list `letters` holds: "def" "abc"
Moved-from string `s` holds: ""

See also

(C++11)
constructs an element in-place at the beginning
(public member function)
(C++11)
removes the first element
(public member function)
creates a std::front_insert_iterator of type inferred from the argument
(function template)

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