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# std::move

From cppreference.com
< cpp‎ | algorithm

Defined in header `<algorithm>` |  |
template< class InputIt, class OutputIt > OutputIt move( InputIt first, InputIt last, OutputIt d_first ); |  | (since C++11)

Moves the elements in the range `[first, last)`, to another range beginning at `d_first`. After this operation 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.

### [edit] Parameters

first, last | - | the range of elements to move
d_first | - | the beginning of the destination range. If `d_first` is within `[first, last)`, std::move_backward must be used instead of std::move.
Type requirements
- `InputIt` must meet the requirements of `InputIterator`.
- `OutputIt` must meet the requirements of `OutputIterator`.

### [edit] Return value

Output iterator to the element past the last element moved (d_first + (last - first))

### [edit] Complexity

Exactly `last - first` move assignments.

### [edit] Possible implementation

    template<class InputIt, class OutputIt>
    OutputIt move(InputIt first, InputIt last, OutputIt d_first)
    {
        while (first != last) {
            *d_first++ = std::move(*first++);
        }
        return d_first;
    }

### [edit] Notes

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

### [edit] Example

The following code moves thread objects (which themselves are not copyable) from one container to another.

Run this code

    #include <iostream>
    #include <vector>
    #include <list>
    #include <iterator>
    #include <thread>
    #include <chrono>

    void f(int n)
    {
        std::this_thread::sleep_for(std::chrono::seconds(n));
        std::cout << "thread " << n << " ended" << '\n';
    }

    int main()
    {
        std::vector<std::thread> v;
        v.emplace_back(f, 1);
        v.emplace_back(f, 2);
        v.emplace_back(f, 3);
        std::list<std::thread> l;
        // copy() would not compile, because std::thread is noncopyable

        std::move(v.begin(), v.end(), std::back_inserter(l));
        for (auto& t : l) t.join();
    }

Output:

    thread 1 ended
    thread 2 ended
    thread 3 ended

### [edit] See also

move_backward (C++11) | moves a range of elements to a new location in backwards order (function template) [edit]
move (C++11) | obtains an rvalue reference (function template) [edit]

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