std:: iter_move (std::reverse_iterator)

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std::reverse_iterator
friend constexpr std:: iter_rvalue_reference_t < Iter >
iter_move ( const std:: reverse_iterator & i ) noexcept ( /* see below */ ) ;
(since C++20)

Casts the result of dereferencing the adjusted underlying iterator to its associated rvalue reference type.

Equivalent to auto tmp = i. base ( ) ;
return std :: ranges:: iter_move ( -- tmp ) ; .

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

Parameters

i - a source reverse iterator

Return value

An rvalue reference or a prvalue temporary.

Complexity

Constant.

Exceptions

noexcept specification:
noexcept (

std:: is_nothrow_copy_constructible_v < Iter > &&
noexcept ( std :: ranges:: iter_move ( -- std:: declval < Iter & > ( ) ) )

)

Example

Run this code 
#include <iomanip>
#include <iostream>
#include <iterator>
#include <string>
#include <vector>
 
void print(const auto& rem, const auto& v)
{
    std::cout << rem << '[' << size(v) << "] {";
    for (char comma[]{0, 0}; const auto& s : v)
        std::cout << comma << ' ' << std::quoted(s), comma[0] = ',';
    std::cout << " }\n";
}
 
int main()
{
    std::vector<std::string> p{"Alpha", "Bravo", "Charlie"}, q;
 
    print("p", p), print("q", q);
 
    using RI = std::reverse_iterator<std::vector<std::string>::iterator>;
 
    for (RI iter{p.rbegin()}, rend{p.rend()}; iter != rend; ++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] { "", "", "" }
q[3] { "Charlie", "Bravo", "Alpha" }

See also

(C++20)
casts the result of dereferencing an object to its associated rvalue reference type
(customization point object)
(C++20)
casts the result of dereferencing the underlying iterator to its associated rvalue reference type
(function)
(C++11)
converts the argument to an xvalue
(function template)
(C++11)
converts the argument to an xvalue if the move constructor does not throw
(function template)
(C++11)
forwards a function argument and use the type template argument to preserve its value category
(function template)
(C++20)
moves a range of elements to a new location
(algorithm function object)
(C++20)
moves a range of elements to a new location in backwards order
(algorithm function object)
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