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

 

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std::forward_list

Member functions
forward_list::forward_list forward_list::~forward_list forward_list::operator= forward_list::assign forward_list::assign_range (C++23)   forward_list::get_allocator Element access forward_list::front Iterators forward_list::before_beginforward_list::cbefore_begin forward_list::beginforward_list::cbegin forward_list::endforward_list::cend Capacity forward_list::empty forward_list::max_size	Modifiers forward_list::clear forward_list::emplace_front forward_list::push_front forward_list::insert_after forward_list::emplace_after forward_list::erase_after forward_list::insert_range_after (C++23) forward_list::prepend_range (C++23) forward_list::pop_front forward_list::resize forward_list::swap Operations forward_list::merge forward_list::splice_after forward_list::removeforward_list::remove_if forward_list::reverse forward_list::unique forward_list::sort
Non-member functions
operator==operator<=> (C++20) swap(std::forward_list) erase(std::forward_list)erase_if(std::forward_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)

 

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 for any reason, these functions have no effect (strong exception safety guarantee).

Example

Run this code

#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

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