iter_move(std::counted_iterator) 

friend constexpr std::iter_rvalue_reference_t<I>
    iter_move( const std::counted_iterator& i )
        noexcept(noexcept(ranges::iter_move(i.base())))
            requires std::input_iterator<I>;
 (since C++20)

Casts the result of dereferencing the underlying iterator to its associated rvalue reference type. The behavior is undefined if i.count() is equal to ​0​.

The function body is equivalent to return ranges::iter_move(i.base());.

This function is not visible to ordinary unqualified or qualified lookup, and can only be found by argument-dependent lookup when std::counted_iterator<I> is an associated class of the arguments.

Parameters

i - a source iterator adaptor

Return value

An rvalue reference or a prvalue temporary.

Complexity

Constant.

Example

#include <iomanip>
#include <iostream>
#include <iterator>
#include <string>
#include <vector>
 
void print(auto const& rem, auto const& v)
{
    std::cout << rem << '[' << size(v) << "] {";
    for (char comma[]{0, ' ', 0}; auto const& s : v)
        std::cout << comma << std::quoted(s), *comma = ',';
    std::cout << "}\n";
}
 
int main()
{
    std::vector<std::string> p{"Alpha", "Bravo", "Charlie"}, q;
 
    print("p", p), print("q", q);
 
    using RI = std::counted_iterator<std::vector<std::string>::iterator>;
 
    for (RI iter{p.begin(), 2}; iter != std::default_sentinel; ++iter)
        q.emplace_back(/* ADL */ iter_move(iter));
 
    print("p", p), print("q", q);
}

Possible output:

p[3] {"Alpha", "Bravo", "Charlie"}
q[0] {}
p[3] {"", "", "Charlie"}
q[2] {"Alpha", "Bravo"}

See also

(C++20)
 casts the result of dereferencing an object to its associated rvalue reference type
(customization point object)
(C++20)
 swaps the objects pointed to by two underlying iterators
(function template)
(C++11)
 obtains an rvalue reference
(function template)
(C++11)
 obtains an rvalue reference if the move constructor does not throw
(function template)
(C++11)
 forwards a function argument
(function template)
(C++20)
 moves a range of elements to a new location
(niebloid)
(C++20)
 moves a range of elements to a new location in backwards order
(niebloid)

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