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std::make_move_iterator

Defined in header `<iterator>`
template< class Iter > std::move_iterator<Iter> make_move_iterator( Iter i );		(since C++11) (until C++17)
template< class Iter > constexpr std::move_iterator<Iter> make_move_iterator( Iter i );		(since C++17)

make_move_iterator is a convenience function template that constructs a std::move_iterator for the given iterator i with the type deduced from the type of the argument.

Parameters

input iterator to be converted to move iterator

Return value

A std::move_iterator which can be used to move from the elements accessed through i.

Possible implementation

template< class Iter >
constexpr std::move_iterator<Iter> make_move_iterator( Iter i )
{
    return std::move_iterator<Iter>(std::move(i));
}

Example

#include <iostream>
#include <iomanip>
#include <list>
#include <vector>
#include <string>
#include <iterator>
 
auto print = [](auto const rem, auto const& seq) {
    for (std::cout << rem; auto const& str : seq)
            std::cout << std::quoted(str) << ' ';
    std::cout << '\n';
};
 
int main()
{
    std::list<std::string> s{"one", "two", "three"};
 
    std::vector<std::string> v1(s.begin(), s.end()); // copy
 
    std::vector<std::string> v2(std::make_move_iterator(s.begin()),
                                std::make_move_iterator(s.end())); // move
 
    print("v1 now holds: ", v1);
    print("v2 now holds: ", v2);
    print("original list now holds: ", s);
}

Possible output:

v1 now holds: "one" "two" "three"
v2 now holds: "one" "two" "three"
original list now holds: "" "" ""

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR	Applied to	Behavior as published	Correct behavior
LWG 2061	C++11	`make_move_iterator` did not convert array arguments to pointers	made to convert