friend std::iter_rvalue_reference_t<I> iter_move( const std::common_iterator& i ) noexcept(noexcept(ranges::iter_move(std::declval<const I&>())) 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.var
does not hold an I
object (i.e. an iterator).
The function body is equivalent to: return std::ranges::iter_move(std::get<I>(i.var));
.
This function is not visible to ordinary unqualified or qualified lookup, and can only be found by argument-dependent lookup when std::common_iterator<I,S>
is an associated class of the arguments.
i | - | a source iterator adaptor. |
An rvalue reference or a prvalue temporary.
Constant.
#include <iomanip> #include <iostream> #include <iterator> #include <string> #include <vector> void print(auto const& rem, auto const& v) { std::cout << rem << "[" << size(v) << "] { "; for (int o{}; auto const& s : v) std::cout << (o++ == 0 ? "" : ", ") << quoted(s); std::cout << " }\n"; } int main() { std::vector<std::string> p { "Andromeda", "Cassiopeia", "Phoenix" }, q; print("p", p), print("q", q); using CI = std::common_iterator< std::counted_iterator<std::vector<std::string>::iterator>, std::default_sentinel_t >; CI last{ std::default_sentinel }; for (CI first{ {p.begin(), 2} }; first != last; ++first) { q.emplace_back( /* ADL */ iter_move(first) ); } print("p", p), print("q", q); }
Possible output:
p[3] { "Andromeda", "Cassiopeia", "Phoenix" } q[0] { } p[3] { "", "", "Phoenix" } q[2] { "Andromeda", "Cassiopeia" }
(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) | 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) |
© cppreference.com
Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.
https://en.cppreference.com/w/cpp/iterator/common_iterator/iter_move