libc++ Ranges Status

Overview

This document contains the status of the C++20 Ranges library in libc++. It is used to track both the status of the sub-projects of the ranges library and who is assigned to these sub-projects. This is imperative to effective implementation so that work is not duplicated and implementors are not blocked by each other.

If you are interested in contributing to the libc++ Ranges library, please send a message to the #libcxx channel in the LLVM discord. Please do not start working on any of the assigned items below.

Sub-Projects in the One Ranges Proposal

Section	Description	Dependencies	Assignee	Complete
[tuple.helper]	Update <tuple> includes.	None	Konstantin Varlamov	✅
[range.cmp]	ranges::equal_to ranges::not_equal_to ranges::less ranges::greater ranges::less_equal ranges::greater_equal	None	Zoe Carver	✅
[readable.traits]	indirectly_readable_traits iter_value_t	None	Christopher Di Bella	✅
[incrementable.traits]	incrementable_traits iter_difference_t		Christopher Di Bella	✅
[iterator.traits]	Updates to iterator_traits	indirectly_readable_traits incrementable_traits	Christopher Di Bella	✅
[special.mem.concepts]	nothrow-input-iterator nothrow-sentinel-for nothrow-input-range nothrow-forward-iterator nothrow-forward-range	[iterator.concepts] [range.refinements]	Konstantin Varlamov	✅
[specialized.algorithms]	ranges::uninitialized_default_construct ranges::uninitialized_default_construct_n ranges::uninitialized_value_construct ranges::uninitialized_value_construct_n ranges::uninitialized_copy ranges::uninitialized_copy_n ranges::uninitialized_move ranges::uninitialized_move_n ranges::uninitialized_fill ranges::uninitialized_fill_n ranges::construct_at ranges::destroy ranges::destroy_at ranges::destroy_n	[special.mem.concepts]	Konstantin Varlamov	✅
[strings]	Adds begin/end and updates const_iterator.	[iterator.concepts]	Konstantin Varlamov	✅
[views.span]	Same as [strings]	[iterator.concepts]	Konstantin Varlamov	✅
[iterator.cust.move]	ranges::iter_move		Zoe Carver	✅
[iterator.cust.swap]	ranges::iter_swap	iter_value_t	Zoe Carver	✅
[iterator.concepts]	indirectly_readable indirectly_writable weakly_incrementable incrementable input_or_output_iterator sentinel_for sized_sentinel_for input_iterator output_iterator forward_iterator bidirectional_iterator random_access_iterator contiguous_iterator		Various	✅
[indirectcallable.indirectinvocable]	indirectly_unary_invocable indirectly_regular_unary_invocable indirectly_unary_predicate indirectly_binary_predicate indirectly_equivalence_relation indirectly_strict_weak_order	[readable.traits]	Louis Dionne	✅
[projected]	ranges::projected	[iterator.concepts]	Louis Dionne	✅
[alg.req]: pt. 1	indirectly_movable indirectly_movable_storable indirectly_copyable indirectly_copyable_storable	[iterator.concepts]	Zoe Carver and Konstantin Varlamov	✅
[alg.req]: pt. 2	indirectly_swappable	[iterator.concepts] [iterator.cust.swap]	Zoe Carver	✅
[alg.req]: pt. 3	indirectly_comparable	[projected]	Nikolas Klauser	✅
[alg.req]: pt. 4	permutable mergeable sortable	[iterator.concepts]	Konstantin Varlamov	✅
[std.iterator.tags]	contiguous_iterator_tag iterator_concept specialization for pointers	[iterator.traits]	Eric Fiselier	✅
[range.iter.ops]	ranges::advance ranges::distance ranges::next ranges::prev	[iterator.concepts]	Christopher Di Bella and Arthur O’Dwyer	✅
[predef.iterators]	Updates to reverse_iterator Updates to back_insert_iterator Updates to front_insert_iterator Updates to move_iterator	[iterator.concepts] [iterator.cust.swap] [iterator.cust.move]	Various	✅
[move.sentinel]	move_sentinel	[predef.iterators]	Arthur O’Dwyer	✅
[common.iterator]	common_iterator	[iterator.concepts] [iterator.cust.swap] [iterator.cust.move]	Zoe Carver	✅
[default.sentinel]	std::default_sentinel_t	No dependencies	Zoe Carver	✅
[counted.iterator]	counted_iterator	[iterator.concepts] [iterator.cust.swap] [iterator.cust.move] [default.sentinels]	Zoe Carver	✅
[stream.iterators]	Updates to istream_iterator Updates to ostream_iterator Updates to istreambuf_iterator Updates to ostreambuf_iterator	[default.sentinels]	Various	✅
[range.access]	ranges::begin ranges::end range::cbegin ranges::cend ranges::rbegin ranges::rend ranges::crbegin ranges::crend ranges::size ranges::ssize ranges::empty ranges::data ranges::cdata	[iterator.concepts]	Various	✅
[range.range]	ranges::range ranges::borrowed_range ranges::enable_borrowed_range ranges::iterator_t ranges::sentinel_t ranges::range_difference_t ranges::range_size_t ranges::range_value_t ranges::range_reference_t ranges::range_rvalue_reference_t	[range.access]	Christopher Di Bella	✅
[range.sized]	ranges::sized_range ranges::disable_sized_range	[range.primitives] [range.range]	Christopher Di Bella	✅
[range.view]	ranges::enable_view ranges::view_base ranges::view	[range.range]	Louis Dionne	✅
[range.refinements]	ranges::output_range ranges::input_range ranges::forward_range ranges::bidirectional_range ranges::random_access_range ranges::contiguous_range ranges::common_range	[range.range]	Christopher Di Bella	✅
[range.refinements]	ranges::viewable_range	[range.range]	Louis Dionne	✅
[range.utility.helpers]	simple-view has-arrow not-same-as	[range.range] [iterator.concept.input]	Zoe Carver	✅
[view.interface]	ranges::view_interface	[ranges.range] [range.view] [range.iterator.op.prev] [range.refinements]	Zoe Carver	✅
[range.subrange]	ranges::subrange	[view.interface]	Zoe Carver	✅
[range.dangling]	ranges::dangling ranges::borrowed_iterator_t ranges::borrowed_subrange_t	[range.range] [range.subrange]	Christopher Di Bella	✅
[range.empty]	empty_view	[view.interface]	Zoe Carver	✅
[range.single]	single_view	[view.interface]	Zoe Carver	✅
[range.iota]	iota_view	[range.all]	Zoe Carver	✅
[range.all]	view::all	[range.subrange], [range.view.ref]	Zoe Carver	✅
[range.ref.view]	ref_view	[view.interface]	Zoe Carver	✅
[range.filter]	filter_view	[range.all]	Louis Dionne	✅
[range.transform]	transform_view	[range.all]	Zoe Carver	✅
[range.take]	take_view	[range.all]	Zoe Carver	✅
[range.join]	join_view	[range.all]	Zoe Carver	✅
[range.split]	split_view (renamed to lazy_split_view by P2210)	[range.all]	Zoe Carver and Konstantin Varlamov	✅
[range.counted]	view::counted	[range.subrange]	Zoe Carver	✅
[range.common]	common_view	[range.all]	Zoe Carver	✅
[range.reverse]	reverse_view	[range.all]	Zoe Carver	✅

Category	Algorithm	Assignee	CL	Complete
Search	any_of	Nikolas Klauser	D123016	✅
Search	all_of	Nikolas Klauser	D123016	✅
Search	none_of	Nikolas Klauser	D123016	✅
Search	find	Nikolas Klauser	D121248	✅
Search	find_if	Nikolas Klauser	D121248	✅
Search	find_if_not	Nikolas Klauser	D121248	✅
Search	find_first_of	Nikolas Klauser	D126529	✅
Search	adjacent_find	Nikolas Klauser	D126610	✅
Search	mismatch	Nikolas Klauser	D117817	✅
Search	equal	Nikolas Klauser	D123681	✅
Search	lexicographical_compare	Nikolas Klauser	D127130	✅
Search	partition_point	Konstantin Varlamov	D130070	✅
Search	lower_bound	Nikolas Klauser	D121964	✅
Search	upper_bound	Nikolas Klauser	D121964	✅
Search	equal_range	Hui Xie	D129796	✅
Search	binary_search	Nikolas Klauser	D121964	✅
Search	min	Nikolas Klauser	D119589	✅
Search	max	Nikolas Klauser	D122002	✅
Search	minmax	Nikolas Klauser	D120637	✅
Search	min_element	Nikolas Klauser	D117025	✅
Search	max_element	Nikolas Klauser	D117523	✅
Search	minmax_element	Nikolas Klauser	D120637	✅
Search	count	Nikolas Klauser	D121523	✅
Search	count_if	Nikolas Klauser	D121523	✅
Search	search	Nikolas Klauser	D124079	✅
Search	search_n	Nikolas Klauser	D124079	✅
Search	find_end	Nikolas Klauser	D124079	✅
Read-only	is_partitioned	Nikolas Klauser	D124440	✅
Read-only	is_sorted	Nikolas Klauser	D125608	✅
Read-only	is_sorted_until	Nikolas Klauser	D125608	✅
Read-only	includes	Hui Xie	D130116	✅
Read-only	is_heap	Konstantin Varlamov	D130547	✅
Read-only	is_heap_until	Konstantin Varlamov	D130547	✅
Read-only	clamp	Nikolas Klauser	D126193	✅
Read-only	is_permutation	Nikolas Klauser	D127194	✅
Read-only	for_each	Nikolas Klauser	D124332	✅
Read-only	for_each_n	Nikolas Klauser	D124332	✅
Write	copy	Nikolas Klauser	D122982	✅
Write	copy_if	Nikolas Klauser	D122982	✅
Write	copy_n	Nikolas Klauser	D122982	✅
Write	copy_backward	Nikolas Klauser	D122982	✅
Write	move	Nikolas Klauser	D126616	✅
Write	move_backward	Nikolas Klauser	D126616	✅
Write	fill	Nikolas Klauser	D123462	✅
Write	fill_n	Nikolas Klauser	D123462	✅
Write	transform	Nikolas Klauser	D122173	✅
Write	generate	Konstantin Varlamov	D130552	✅
Write	generate_n	Konstantin Varlamov	D130552	✅
Write	remove_copy	Nikolas Klauser	D130599	✅
Write	remove_copy_if	Nikolas Klauser	D130599	✅
Write	replace	Nikolas Klauser	D126283	✅
Write	replace_if	Nikolas Klauser	D126283	✅
Write	replace_copy	Nikolas Klauser	D129806	✅
Write	replace_copy_if	Nikolas Klauser	D129806	✅
Write	swap_ranges	Nikolas Klauser	D116303	✅
Write	reverse_copy	Nikolas Klauser	D127211	✅
Write	rotate_copy	Nikolas Klauser	D127211	✅
Write	sample	Konstantin Varlamov	D130865	✅
Write	unique_copy	Hui Xie	D130404	✅
Write	partition_copy	Konstantin Varlamov	D130070	✅
Write	partial_sort_copy	Konstantin Varlamov	D130532	✅
Merge	merge	Hui Xie	D128611	✅
Merge	set_difference	Hui Xie	D128983	✅
Merge	set_intersection	Hui Xie	D129233	✅
Merge	set_symmetric_difference	Hui Xie	D129520	✅
Merge	set_union	Hui Xie	D129657	✅
Permutation	remove	Nikolas Klauser	D128618	✅
Permutation	remove_if	Nikolas Klauser	D128618	✅
Permutation	reverse	Nikolas Klauser	D125752	✅
Permutation	rotate	Konstantin Varlamov and Nikolas Klauser	D130758	✅
Permutation	shuffle	Konstantin Varlamov	D130321	✅
Permutation	unique	Hui Xie	D130404	✅
Permutation	partition	Konstantin Varlamov	D129624	✅
Permutation	stable_partition	Konstantin Varlamov	D129624	✅
Permutation	sort	Konstantin Varlamov	D127557	✅
Permutation	stable_sort	Konstantin Varlamov	D127834	✅
Permutation	nth_element	Konstantin Varlamov	D128149	✅
Permutation	partial_sort	Konstantin Varlamov	D128744	✅
Permutation	inplace_merge	Hui Xie	D130627	✅
Permutation	make_heap	Konstantin Varlamov	D128115	✅
Permutation	push_heap	Konstantin Varlamov	D128115	✅
Permutation	pop_heap	Konstantin Varlamov	D128115	✅
Permutation	sort_heap	Konstantin Varlamov	D128115	✅
Permutation	next_permutation	Nikolas Klauser	D129859	✅
Permutation	prev_permutation	Nikolas Klauser	D129859	✅
Uninitialised memory	uninitialized_copy	Konstantin Varlamov	D116023	✅
Uninitialised memory	uninitialized_copy_n	Konstantin Varlamov	D116023	✅
Uninitialised memory	uninitialized_fill	Konstantin Varlamov	D115626	✅
Uninitialised memory	uninitialized_fill_n	Konstantin Varlamov	D115626	✅
Uninitialised memory	uninitialized_move	Konstantin Varlamov	D116023	✅
Uninitialised memory	uninitialized_move_n	Konstantin Varlamov	D116023	✅
Uninitialised memory	uninitialized_default_construct	Konstantin Varlamov	D115315	✅
Uninitialised memory	uninitialized_default_construct_n	Konstantin Varlamov	D115315	✅
Uninitialised memory	uninitialized_value_construct	Konstantin Varlamov	D115626	✅
Uninitialised memory	uninitialized_value_construct_n	Konstantin Varlamov	D115626	✅
Uninitialised memory	destroy	Konstantin Varlamov	D116078	✅
Uninitialised memory	destroy_n	Konstantin Varlamov	D116078	✅
Uninitialised memory	destroy_at	Konstantin Varlamov	D116078	✅
Uninitialised memory	construct_at	Konstantin Varlamov	D116078	✅

Misc. Items and TODOs

(Note: files with required updates will contain the TODO at the beginning of the list item so they can be easily found via global search.)

• TODO(XX_SPACESHIP_CONCEPTS): when spaceship support is added to various STL types, we need to update some concept tests.

Paper and Issue Status

(Note: stolen from MSVC here.)

Number	Name	Status	First released version
P0896R4	<ranges>	Complete	15.0
P1035R7	Input Range Adaptors
P1207R4	Movability Of Single-Pass Iterators	Complete	15.0
P1243R4	Rangify New Algorithms	Complete	15.0
P1248R1	Fixing Relations	Complete	13.0
P1252R2	Ranges Design Cleanup	Complete	15.0
P1391R4	Range Constructor For string_view	Complete	14.0
P1456R1	Move-Only Views	Complete	15.0
P1474R1	Helpful Pointers For contiguous_iterator	Complete	15.0
P1522R1	Iterator Difference Type And Integer Overflow	Complete	15.0
P1523R1	Views And Size Types	Complete	15.0
P1638R1	basic_istream_view::iterator Should Not Be Copyable
P1716R3	Range Comparison Algorithms Are Over-Constrained	Complete	15.0
P1739R4	Avoiding Template Bloat For Ranges	Complete	15.0
P1862R1	Range Adaptors For Non-Copyable Iterators
P1870R1	forwarding-range<T> is too subtle	Complete	15.0
P1871R1	Concept traits should be named after concepts	Complete	14.0
P1878R1	Constraining Readable Types	Complete	15.0
P1970R2	Consistency for size() functions: Add ranges::ssize	Complete	15.0
P1983R0	Wording for GB301, US296, US292, US291, and US283	Complete	15.0
P1994R1	elements_view Needs Its Own sentinel
P2091R0	Fixing Issues With Range Access CPOs	Complete	15.0
P2106R0	Alternative wording for GB315 and GB316	Complete	15.0
P2325R3	Views should not be required to be default constructible
P2328R1	join_view should join all views of ranges	Complete	14.0
P2210R2	Superior String Splitting
P2281R1	Clarifying range adaptor objects	Complete	14.0
P2367R0	Remove misuses of list-initialization from Clause 24
P2415	What is a view	Complete	14.0
P2432	Fix istream_view