deref-move

 

C++

Compiler support

Freestanding and hosted

Language

Standard library

Standard library headers

Named requirements

Feature test macros (C++20)

Language support library

Concepts library (C++20)

Diagnostics library

Memory management library

Metaprogramming library (C++11)

General utilities library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Strings library

Text processing library

Numerics library

Date and time library

Input/output library

Filesystem library (C++17)

Concurrency support library (C++11)

Execution control library (C++26)

Technical specifications

Symbols index

External libraries

 

Algorithm library

Constrained algorithms and algorithms on ranges (C++20)
Constrained algorithms, e.g. ranges::copy, ranges::sort, ...
Non-modifying sequence operations     Batch operations for_each for_each_n (C++17) Search operations all_ofany_ofnone_of (C++11)(C++11)(C++11) countcount_if mismatch equal findfind_iffind_if_not (C++11) find_end find_first_of adjacent_find search search_n Modifying sequence operations Copy operations copycopy_if (C++11) copy_backward copy_n (C++11) move (C++11) move_backward (C++11) Swap operations swap iter_swap swap_ranges Transformation operations replacereplace_if transform replace_copyreplace_copy_if Generation operations fill fill_n generate generate_n Removing operations removeremove_if unique remove_copyremove_copy_if unique_copy Order-changing operations reverse reverse_copy rotate rotate_copy random_shuffleshuffle (until C++17)(C++11) shift_leftshift_right (C++20)(C++20) Sampling operations sample (C++17)	Sorting and related operations Partitioning operations partition partition_copy (C++11)     stable_partition is_partitioned (C++11)     partition_point (C++11) Sorting operations sort stable_sort partial_sort partial_sort_copy is_sorted (C++11) is_sorted_until (C++11) nth_element Binary search operations (on partitioned ranges) lower_bound upper_bound equal_range binary_search Set operations (on sorted ranges) includes set_union set_intersection          set_difference set_symmetric_difference Merge operations (on sorted ranges) merge inplace_merge Heap operations push_heap pop_heap make_heap sort_heap is_heap (C++11) is_heap_until (C++11) Minimum/maximum operations max min minmax (C++11) clamp (C++17) max_element min_element minmax_element (C++11) Lexicographical comparison operations lexicographical_compare lexicographical_compare_three_way (C++20) Permutation operations next_permutation prev_permutation is_permutation (C++11)	Execution policies (C++17) is_execution_policy (C++17) execution::seqexecution::parexecution::par_unseqexecution::unseq (C++17)(C++17)(C++17)(C++20) execution-policy (exposition only*)(C++26) execution::sequenced_policyexecution::parallel_policyexecution::parallel_unsequenced_policyexecution::parallel_unsequenced (C++17)(C++17)(C++17)(C++20) Numeric operations iota (C++11) inner_product      reduce (C++17) accumulate adjacent_difference transform_reduce (C++17) partial_sum inclusive_scan (C++17)     exclusive_scan (C++17) transform_inclusive_scan (C++17) transform_exclusive_scan (C++17) Specialized <memory> algorithms Specialized <random> algorithms ranges::generate_random (C++26) C library qsort bsearch

 

Specialized <memory> algorithms

Helper templates (exposition only*) voidify deref-move (C++17) nothrow-input-iteratornothrow-forward-iteratornothrow-bidirectional-iteratornothrow-random-access-iterator (C++20)(C++20)(C++26)(C++26) nothrow-sentinel-fornothrow-sized-sentinel-for (C++20)(C++26) nothrow-input-rangenothrow-forward-rangenothrow-bidirectional-rangenothrow-random-access-rangenothrow-sized-random-access-range (C++20)(C++20)(C++26)(C++26)(C++26) Object (batch) construction construct_at (C++20) uninitialized_copy uninitialized_fill uninitialized_move (C++17) uninitialized_copy_n (C++11)     uninitialized_fill_n uninitialized_move_n (C++17) ranges::construct_at (C++20) ranges::uninitialized_copy (C++20) ranges::uninitialized_fill (C++20) ranges::uninitialized_move (C++20) ranges::uninitialized_copy_n (C++20) ranges::uninitialized_fill_n (C++20) ranges::uninitialized_move_n (C++20) uninitialized_default_construct (C++17) ranges::uninitialized_default_construct (C++20) uninitialized_default_construct_n (C++17) ranges::uninitialized_default_construct_n (C++20) uninitialized_value_construct (C++17) ranges::uninitialized_value_construct (C++20) uninitialized_value_construct_n (C++17) ranges::uninitialized_value_construct_n (C++20) Object (batch) destruction destroy (C++17) destroy_n (C++17) destroy_at (C++17) ranges::destroy (C++20) ranges::destroy_n (C++20) ranges::destroy_at (C++20)

 

template< class I > constexpr decltype(auto) /*deref-move*/( I& iter )		(since C++17) (exposition only*)

Returns the result of dereferencing iter as an rvalue:

• If *iter is of an lvalue reference type, returns std::move(*iter).
• Otherwise returns *iter directly.

Parameters

iter

-

the iterator for which the referred object will be moved

Return value

As described above.

Notes

This exposition-only function template is introduced by the resolution of LWG issue 3918. It is used to prevent the unnecessary move construction from the result of dereferencing iter if the result is already an rvalue.

See also

uninitialized_move (C++17)	moves a range of objects to an uninitialized area of memory (function template & algorithm function object)
ranges::uninitialized_move (C++20)
uninitialized_move_n (C++17)	moves a number of objects to an uninitialized area of memory (function template & algorithm function object)
ranges::uninitialized_move_n (C++20)