std::move
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.
Contents |
[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] Example
The following code moves thread objects (which themselves are not copyable) from one container to another.
#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
(C++11)
|
moves a range of elements to a new location in backwards order (function template) |
(C++11)
|
obtains an rvalue reference (function template) |