std::ranges::move, std::ranges::move_result

Defined in header <algorithm>
Call signature
template< std::input_iterator I, std::sentinel_for<I> S, std::weakly_incrementable O >
requires std::indirectly_movable<I, O>
constexpr move_result<I, O>
    move( I first, S last, O result );
(1) (since C++20)
template< ranges::input_range R, std::weakly_incrementable O >
requires std::indirectly_movable<ranges::iterator_t<R>, O>
constexpr move_result<ranges::borrowed_iterator_t<R>, O>
    move( R&& r, O result );
(2) (since C++20)
Helper types
template< class I, class O >
using move_result = ranges::in_out_result<I, O>;
(3) (since C++20)
1) Moves the elements in the range, defined by [firstlast), to another range beginning at result. The behavior is undefined if result is within the range [firstlast). In such a case, ranges::move_backward may be used instead.
2) Same as (1), but uses r as the source range, as if using ranges::begin(r) as first, and ranges::end(r) as last.

The elements in the moved-from range will still contain valid values of the appropriate type, but not necessarily the same values as before the move.

The function-like entities described on this page are niebloids, that is:

In practice, they may be implemented as function objects, or with special compiler extensions.


first - the beginning of the range of elements to move
last - the end of the range of elements to move
r - the range of the elements to move
result - the beginning of the destination range

Return value

{last, result + N}, where.

1) N = ranges::distance(first, last).
2) N = ranges::distance(r).


Exactly N move assignments.


When moving overlapping ranges, ranges::move is appropriate when moving to the left (beginning of the destination range is outside the source range) while ranges::move_backward is appropriate when moving to the right (end of the destination range is outside the source range).

Possible implementation

struct move_fn
    template<std::input_iterator I, std::sentinel_for<I> S, std::weakly_incrementable O>
    requires std::indirectly_movable<I, O>
    constexpr ranges::move_result<I, O>
        operator()(I first, S last, O result) const
        for (; first != last; ++first, ++result)
            *result = ranges::iter_move(first);
        return {std::move(first), std::move(result)};
    template<ranges::input_range R, std::weakly_incrementable O>
    requires std::indirectly_movable<ranges::iterator_t<R>, O>
    constexpr ranges::move_result<ranges::borrowed_iterator_t<R>, O>
        operator()(R&& r, O result) const
        return (*this)(ranges::begin(r), ranges::end(r), std::move(result));
inline constexpr move_fn move {};


The following code moves thread objects (which themselves are non copyable) from one container to another.

#include <algorithm>
#include <chrono>
#include <iostream>
#include <iterator>
#include <list>
#include <thread>
#include <vector>
using namespace std::literals::chrono_literals;
void f(std::chrono::milliseconds n)
    std::cout << "thread with n=" << n.count() << "ms ended" << std::endl;
int main()
    std::vector<std::jthread> v;
    v.emplace_back(f, 400ms);
    v.emplace_back(f, 600ms);
    v.emplace_back(f, 800ms);
    std::list<std::jthread> l;
    // std::ranges::copy() would not compile, because std::jthread is non-copyable
    std::ranges::move(v, std::back_inserter(l));


thread with n=400ms ended
thread with n=600ms ended
thread with n=800ms ended

See also

moves a range of elements to a new location in backwards order
copies a range of elements to a new location
copies a range of elements in backwards order
moves a range of elements to a new location
(function template)
obtains an rvalue reference
(function template)

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