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

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

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

All iterators, including the end() iterator, are invalidated. No 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 <deque>
#include <iomanip>
#include <iostream>
#include <string>
 
int main()
{
    std::deque<std::string> letters;
 
    letters.push_front("abc");
    std::string s{"def"};
    letters.push_front(std::move(s));
 
    std::cout << "std::deque `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::deque `letters` holds: "def" "abc"
Moved-from string `s` holds: ""

emplace_front (C++11)	constructs an element in-place at the beginning (public member function)
push_back	adds an element to the end (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)