Computer programming language
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C++23 , formallyISO/IEC 14882:2024 ,[ 1] open standard for theC++ programming language that followsC++20 . The final draft of this version is N4950.[ 2] [ 3]
In February 2020, at the final meeting forC++20 in Prague, an overall plan for C++23 was adopted:[ 4] [ 5] coroutines , amodular standard library, executors, and networking.
The first WG21 meeting focused on C++23 was intended to take place inVarna in early June 2020, but was cancelled due to theCOVID-19 pandemic ,[ 6] [ 7] New York [ 8] [ 7] Kona, Hawaii .[ 8] [ 8] Issaquah in February 2023.[ 9]
[ edit ] After many library changes applied to the working draft, the new"Hello, world" program will be:[1]
import std ; int main () { std :: println ( "Hello, world!" ); } Changes that have been accepted into C++23 include:
explicitthis object parameter[ 10] if consteval[ 11] multidimensional subscript operator[ 12] static call and subscript operators and static lambdas[ 13] [ 14] simplifying implicit move[ 15] auto(x) andauto{x}[ 16] new preprocessor directives: extending the lifetime of some temporaries in range-based for loop[ 19] new standard attribute[[assume(expression)]][ 20] class template argument deduction from inherited constructors[ 21] labels at the end of the compound statement[ 22] alias declarations in init-statements[ 23] literal suffixes forstd::size_t and the corresponding signed type[ 24] extended floating-point types with literals (conditionally supported)[ 25] optional() from nullarylambda expressions [ 26] attributes on lambda expressions[ 27] constexpr changes:non-literal variables, labels, andgotos inconstexpr functions[ 28] allowingstatic andthread_local variables that are usable in constant expressions inconstexpr functions[ 29] constexpr function does not need its return type and parameter types to be literal typeit is now possible to write aconstexpr function for which no invocation satisfies the requirements of a core constant expression[ 30] narrowing contextual conversions tobool instatic_assert andif constexpr[ 31] trimming whitespaces before line splicing[ 32] make declaration order layout mandated[ 33] delimited escape sequences[ 34] named universal character escapes[ 35] text encoding changes:support for UTF-8 as a portable source file encoding[ 36] consistent character literal encoding[ 37] character sets and encodings[ 38] Standard Library Module Support [ edit ] Coroutine Library Support [ edit ] synchronous coroutinestd::generator for ranges[ 40] General Utilities Support [ edit ] result typestd::expected[ 41] monadic operations forstd::optional[ 42] std::expected[ 43] utility functionstd::to_underlying to get the underlying value of enum[ 44] move-only callable wrapperstd::move_only_function[ 45] std::forward_like[ 46] std::invoke_r[ 47] std::bind_back[ 48] std::byteswap[ 49] std::unreachable: a function to markunreachable code [ 50] madestd::tuple compatible with othertuple-like objects[ 51] std::basic_common_reference specialization forstd::reference_wrapper yielding reference types[ 52] adding default arguments forstd::pair's forwarding constructor[ 53] Compile-time Support [ edit ] constexpr support for:std::type_info::operator==[ 54] std::bitset[ 55] std::unique_ptr[ 56] for some<cmath> functions[ 57] for integral overloads ofstd::to_chars andstd::from_chars[ 58] metaprogramming utilities:type traitsstd::is_scoped_enum,[ 59] std::is_implicit_lifetime,[ 60] std::reference_constructs_from_temporary, andstd::reference_converts_from_temporary.[ 61] adding move-only types support for comparison concepts[ 62] [ edit ] new range conversion functionstd::ranges::to[ 63] new constrained ranges algorithm:std::ranges::starts_withstd::ranges::ends_with[ 64] std::ranges::containsstd::ranges::contains_subrange[ 65] std::ranges::find_last and other variants[ 66] rangified versions ofiota,shift_left, andshift_right[ 67] range fold algorithms[ 68] newstd::ranges::range_adaptor_closure, a helper for defining user-defined range adaptor closures[ 48] new range adaptors:std::views::zip and other variantsstd::views::adjacent and other variants[ 69] std::views::join_with[ 70] std::views::slidestd::views::chunk[ 71] std::views::chunk_by[ 72] std::views::as_rvalue[ 73] std::views::as_const[ 74] std::views::repeat[ 75] std::views::stride[ 76] std::views::cartesian_product[ 77] std::views::enumerate[ 78] rectifying constant iterators, sentinels, and ranges, that is,std::ranges::cbegin and other similar utilities returning constant iterators should be fully guaranteed even for shallow-const views (such asstd::span)[ 74] ranges iterators as inputs to non-ranges algorithms[ 79] relaxing range adaptors to allow for move only types[ 80] making multi-param constructors of some viewsexplicit[ 81] Memory Management Support [ edit ] std::out_ptr andstd::inout_ptr for C interoperability[ 82] std::allocate_at_least andstd::allocator::allocate_at_least[ 83] explicit lifetime management functionstd::start_lifetime_as for implicit-lifetime types[ 84] disallowing user specialization ofstd::allocator_traits[ 85] String and Text Processing Support [ edit ] new member functions and changes in string types:std::basic_string_view::contains andstd::basic_string::contains[ 86] disabling construction fromnullptr forstd::basic_string andstd::basic_string_view[ 87] explicit range constructor forstd::basic_string_view[ 88] std::basic_string::resize_and_overwrite[ 89] rvalue reference overload ofstd::basic_string::substr for efficient slicing[ 90] formatting ranges, tuples, escaped presentation of characters and strings,std::thread::id, and stacktraces.[ 91] [ 92] [ 93] formatted output functionsstd::print andstd::println from new header<print>[ 95] spanstream library (std::span-based string stream) from new header<spanstream>[ 96] a support for exclusive mode instd::fstreams[ 97] std::basic_ostream::operator<<(const volatile void*)[ 98] multidimensional-spanstd::mdspan[ 99] [ 100] [ 101] [ 102] constructability and assignability of containers from other compatible ranges[ 63] flat set and flat map container adapters[ 103] [ 104] non-deduction context for allocators in container deduction guides[ 105] heterogeneous erasure overloads for associative containers[ 106] allowing iterator pair construction in stack and queue[ 107] requiringstd::span andstd::basic_string_view to be trivially copyable[ 108] C-Compatibility Support [ edit ] new header<stdatomic.h>[ 109] Language defect reports [ edit ] C++ identifier syntax using Unicode Standard Annex 31[ 110] allowing duplicate attributes[ 111] changing scope of lambda trailing return type[ 112] making overloaded comparison operators less breaking change[ 113] undeprecating volatile compound assignments[ 114] [ 115] fixing the compatibility and portability ofchar8_t[ 116] relaxing requirements onwchar_t to match existing practices[ 117] allowing some pointers and references ofthis or unknown origin in constant expressions[ 118] introduction of immediate-escalating functions promoted to immediate functions[ 119] allowingstatic_assert(false) in uninstantiated template contexts Library defect reports [ edit ] changes in ranges library:conditionally borrowed ranges[ 120] repairing input range adaptors andstd::counted_iterator[ 121] relaxing the constraint onstd::ranges::join_view[ 122] renamedstd::ranges::split_view tostd::ranges::lazy_split_view and newsplit_view[ 123] removedstd::default_initializable constraint from conceptstd::ranges::view[ 124] view with ownership and newstd::ranges::owning_view[ 125] fixedstd::ranges::istream_view[ 126] changes in text formatting library:std::basic_format_string[ 127] compile-time format string checks reducing binary code size ofstd::format_to[ 128] fixing locale handling in chrono formatters[ 129] improving width estimation[ 130] std::format[ 131] use of forwarding references in format arguments to allow non-const-formattable types[ 132] fullyconstexprstd::variant andstd::optional[ 133] supporting types derived fromstd::variant instd::visit[ 134] Removed features and deprecation [ edit ] Removed features:
Garbage Collection Support and (strict) Pointer Safety[ 135] relaxed pointer safety is to be relied upon[ 136] [ 137] Boehm GC (and it can also just be used for leak detection in leak detection, when in debug mode), and such GC is often implemented in C++, for other languages to use. Mixed wide-string literal concatenation.[ 138] Non-encodable wide character literals and multicharacter wide character literals.[ 139] Deprecated features:
std::aligned_storage andstd::aligned_union[ 140] std::numeric_limits::has_denorm[ 141] Reverted deprecated features:
Use of comma operator in subscript expressions was no longer deprecated but the semantics has been changed to support overloadable n-adicoperator[]. C headers (The corresponding<*.h> headers for compatibility with C) Published as Technical Specifications [ edit ] Clang progressively added partial C++23 support from 2021 in version 13 through to version 18 in 2024, available through the option-std=c++23.[ 143] GCC added partial, experimental C++23 support in 2021 in version 11 through the option-std=c++2b or-std=c++23 It also has an option to enable GNU extensions in addition to the experimental C++23 support,-std=gnu++2b.[ 144] In the absence of face-to-face WG21 meetings, the following changes were applied after several virtual WG21 meetings, where they were approved by straw polls.
The following were added after the virtual WG21 meeting of 9 November 2020, where they were approved by straw polls:[ 145]
Literal suffixes forstd::size_t and the corresponding signed type A member functioncontains std :: basic_string std :: basic_string_view Astacktrace library (< stacktrace > Boost .Stacktrace A type traitstd :: is_scoped_enum The header< stdatomic . h > C atomics After the virtual WG21 meeting of 22 February 2021, following features are added where they were approved by straw polls:[ 146]
Removing unnecessary empty parameter list() lambda expressions . Repairing input range adaptors andcounted_iterator Relax the requirements fortime_point :: clock [ 147] std :: visit std :: variant Locks lock lockables.[ 148] Conditionally borrowed ranges. std :: to_underlying After the summer 2021 ISO C++ standards plenary virtual meeting of June 2021, new features and defect reports were approved by straw polls:[ 149]
Consteval if (if consteval Narrowing contextual conversions tobool Allowing duplicate attributes. std :: span < spanstream > std :: out_ptr () std :: inout_ptr () constexpr std :: optional std :: variant std :: type_info :: operator == Iterators pair constructors forstd :: stack stack ) andstd :: queue queue ). Few changes of the ranges library:Generalizedstarts_with ends_with Renamedsplit_view lazy_split_view split_view Relaxing the constraint onjoin_view Removingdefault_initializable view Range constructor forstd :: basic_string_view Prohibitingstd :: basic_string std :: basic_string_view nullptr std :: invoke_r Improvements onstd :: format Adding default arguments forstd :: pair After the autumn 2021 ISO C++ standards plenary virtual meeting of October 2021, new features and defect reports were approved by straw polls:[ 150]
Non-literal variables, labels, and gotos inconstexpr Explicitthis Changes on character sets and encodings. New preprocessors:#elifdef #elifndef C23 (C language update) andGCC 12.[ 151] Allowing alias declarations in init-statement. Overloading multidimensional subscript operator (e.g.arr [ 1 , 2 ] Decay copy in language:auto ( x ) auto { x } Changes in text formatting library:Fixing locale handling in chrono formatters. Use of forwarding references in format arguments to allowstd :: generator Addition of type aliasstd :: pmr :: stacktrace std :: basic_stacktrace < std :: pmr :: polymorphic_allocator > [ 152] Changes in ranges library:Refined definition of a view. Replacing function templatestd :: ranges :: istream_view std :: ranges :: istream_view std :: ranges :: wistream_view std :: views :: istream zip zip_view zip_transform_view adjacent_view std :: views :: pairwise std :: views :: adjacent < 2 > adjacent_transform_view std :: views :: pairwise_transform std :: views :: adjacent_transform < 2 > std :: move_only_function Monadic operations forstd :: optional Member function templatestd :: basic_string :: resize_and_overwrite Printingvolatile volatile T * std :: byteswap Heterogeneous erasure overloads for associative containers. Every specialization ofstd :: span std :: basic_string_view Adding conditionalnoexcept std :: exchange [ 153] Revamped specification and use of integer-class types.[ 154] ClarifyC headers . "The headers arenot useful in code that isonly required to be valid C++. Therefore, the C headers should be provided by the C++ standard library as a fully-supported, not deprecated part, but they should also be discouraged for use in code that is not polyglot interoperability code. [..] This proposal makes the C headers no longer deprecated, so there is no formal threat of future removal. The effective discouragement to use the C headers in pure C++ code is now spelled out explicitly as normative discouragement."[ 155] After the virtual WG21 meeting of 7 February 2022, the following features are added where they were approved by straw polls:[ 156]
Allowed attributes on the function call operator of a lambda std :: expected constexpr cmath andcstdlibFunction to markunreachable code ranges :: to A type trait to detect reference binding to temporary Makingstd :: unique_ptr constexpr Pipe support for user-defined range adaptors ranges :: iota ranges :: shift_left ranges :: shift_right views :: join_with Windowing range adaptors:views :: chunk views :: slide views :: chunk_by After the virtual WG21 meeting of 25 July 2022, the following features and defect reports are added where they were approved by straw polls:[ 157]
Made rewriting equality in expressions less of a breaking change. Reverted the deprecation of bitwise assignment tovolatile Added the#warning Removed non-encodable widecharacter literals and multicharacter wide character literals. Allowedlabels to appear at the end of compound statements. Addedescape sequences delimited with curly braces for octal and hexadecimal numbers and universal character names. Allowedconstexpr Simplified some implicit move rules fromC++20 and allowed implicit move when returning an rvalue reference. Add a way to specifyunicode characters by name. For example,U '\ N { LATIN CAPITAL LETTER A WITH MACRON } ' // Equivalent to U'\u0100' Allowedoperator () static Allowed thethis pointer andreferences of unknown origin to appear in constant expressions. Allowed implementations to define extendedfloating-point types in addition to the three standard floating-point types. Added the type aliasesstd::float16_t,std::float32_t,std::float64_t,std::float128_t,std::bfloat16_t <stdfloat>, their corresponding literal suffixesf16f32f64f128bf16orF16F32F64F128BF16 and added overloads to various standard library functions that take floats as arguments. Added the[[ assume ( expression )]] Made support forUTF-8 source files mandatory, providing a portable encoding for source files. Allowed arrays ofchar unsigned char string literals . Removed the requirement thatwchar_t Addedstd::mdspan, a multidimensional array view analogous tostd::span. flat_map flat_set Added thestd :: print std :: println stdout . Provide the named modulesstd std . compat Added support for exclusive modefstreams, analogous to the "x" flag infopen Allowedstd::format to handle ranges, tuples, and other containers. Addedstd::forward_like. Madestd::string::substr usemove semantics . Addedstd :: generator std :: ranges :: input_range views :: cartesian_product views :: repeat views :: stride views :: as_const views :: as_rvalue Added new algorithms:ranges :: find_last ranges :: contains Madestd::tuple compatible with othertuple-like objects. Explicit lifetime management for implicit-lifetime types. Madestd::bitset and integral overloads ofstd::to_chars andstd::from_charsconstexpr Adding move-only types support for comparison concepts. Ranges iterators as inputs to non-ranges algorithms. Relaxing range adaptors to allow for move-only types. After the hybrid WG21 meeting of 7 November 2022, the following features and defect reports are added where they were approved by straw polls:[ 158]
Allowedoperator [] static Allowedstatic thread_local constexpr consteval constexpr consteval Extended the lifetime of temporaries that appear in thefor-range-initializer of a range-basedfor Reverted the deprecation of (all, not just bitwise)compound assignment tovolatile Monadic functions forstd :: expected Synchronize the output ofstd :: print [ 159] After the final hybrid WG21 meeting of 6-11 February 2023, the following features and defect reports are added where they were approved by straw polls:[ 160]
Referencing the Unicode Standard.[ 161] Stashing stashing iterators for proper flattening.[ 162] views::enumeratemaking multi-param constructors of views explicit relaxing ranges just a smidge escaping improvements instd::format improvingstd::format's width estimation std::format fill character allowancesformattingthread::id andstacktrace A type traitstd::is_implicit_lifetime std::common_reference_t ofstd::reference_wrapper should be a reference typedisallowing user specialization ofstd::allocator_traits std::pmr::generatordeprecatingstd::numeric_limits::has_denorm std::barrier's phase completion guarantees^ "ISO/IEC 14882:2024 Programming languages — C++" .iso.org .^ "Working Draft, Standard for Programming Language C++" (PDF) .Open Standards . 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Retrieved2020-02-13 . ^ Lelbach, Bryce Adelstein; Winters, Titus; Fracassi, Fabio; Baker, Billy; Liber, Nevin; Bastien, JF; Stone, David; Ballo, Botond; Keane, Erich; Honermann, Tom (2020-04-20)."P2145R0: Evolving C++ Remotely" .Open Standards .Archived from the original on Feb 12, 2024. ^a b Sutter, Herb (29 July 2020)."Business Plan and Convener's Report: ISO/IEC JTC1/SC22/WG21 (C++)" (PDF) .^a b c "Upcoming Meetings, Past Meetings : Standard C++" .isocpp.org .^ "C++23 "Pandemic Edition" is complete (Trip report: Winter ISO C++ standards meeting, Issaquah, WA, USA)" .herbsutter.com . 13 February 2023.^ Gašper Ažman; Sy Brand; Ben Deane; Barry Revzin (2021-07-12)."Deducing this" . ^ Barry Revzin; Richard Smith; Andrew Sutton; Daveed Vandevoorde (2021-03-22)."if consteval" . ^ Mark Hoemmen; Daisy Hollman; Corentin Jabot; Isabella Muerte; Christian Trott (2021-09-14)."Multidimensional subscript operator" (PDF) . ^ "static operator()" . 2022-04-08.^ "static operator[]" (PDF) . 2022-11-11.^ "Simpler implicit move" . 2022-03-23.^ Zhihao Yuan (2021-07-12)."auto(x): decay-copy in the language" . ^ Melanie Blower (2021-04-30)."Add support for preprocessing directives elifdef and elifndef" (PDF) . ^ Aaron Ballman (2022-01-13)."Support for #warning" (PDF) . ^ "Wording for P2644R1 Fix for Range-based for Loop" . 2022-11-11.^ "Portable assumptions" (PDF) . 2022-04-22.^ Timur Doumler (2022-05-20)."Wording for class template argument deduction from inherited constructors" (PDF) . ^ "Labels at the end of compound statements (C compatibility)" (PDF) . 2022-01-13.^ Jens Maurer (2021-04-13)."Extend init-statement to allow alias-declaration" . ^ JeanHeyd Meneide; Rein Halbersma (2019-11-24)."Literal Suffix for (signed) size_t" . ^ "Extended floating-point types and standard names" . 2022-04-22.^ Alex Christensen; JF Bastien (2020-12-11)."P1102R2: Down with ()!" . ^ "Attributes on Lambda-Expressions" (PDF) .^ Ville Voutilainen (2021-07-12)."Non-literal variables (and labels and gotos) in constexpr functions" . ^ "Permittingstatic constexpr variables inconstexpr functions" . 2022-11-07.^ "Relaxing some constexpr restrictions" . 2022-01-27.^ Andrzej Krzemieński (2021-04-12)."Narrowing contextual conversions to bool" . ^ Corentin Jabot (2021-04-13)."Trimming whitespaces before line splicing" (PDF) . ^ Pal Balog (2021-04-02)."Make declaration order layout mandated" (PDF) . ^ "Delimited escape sequences" (PDF) . 2022-02-25.^ "Named universal character escapes" . 2022-03-25.^ "Support for UTF-8 as a portable source file encoding" (PDF) . 2022-07-01.^ Corentin Jabot (2021-09-14)."Consistent character literal encoding" (PDF) . ^ Jens Maurer (2021-09-21)."Character sets and encodings" . ^ "Standard Library Modules std and std.compat" (PDF) .^ "(std::generator: Synchronous Coroutine Generator for Ranges)" (PDF) .^ Vicente Botet; JF Bastien; Jonathan Wakely (2022-01-07)."std::expected" . ^ Sy Brand (2021-04-27)."Monadic operations for std::optional" . ^ Jeff Garland (2022-09-28)."P2505R5 Monadic Functions forstd::expected" . ^ JeanHeyd Meneide (2021-01-22)."std::to_underlying for enumerations" . ^ Matt Calabrese; Ryan McDougall (2021-07-09)."move_only_function" . ^ Gašper Ažman (2022-05-13)."std::forward_like" (PDF) . ^ Zhihao Yuan (2020-04-29)."invoke_r" . ^a b Barry Revzin (2021-12-17)."Pipe support for user-defined range adaptors" . ^ Isabella Muerte; Corentin Jabot (2021-09-17)."Byteswapping for fun&&nuf" . ^ Melissa Mears; Jens Maurer (2021-10-15)."Function to mark unreachable code" (PDF) . ^ Corentin Jabot (2022-07-15)."Compatibility between tuple, pair and tuple-like objects" (PDF) . ^ Hui Xie; S. Levent Yilmaz; Tim Song (2023-02-07)."common_reference_t of reference_wrapper Should Be a Reference Type" . ^ "Wording for P2644R1 Fix for Range-based for Loop" . 2022-11-11.^ Peter Dimov (2021-05-01)."Making std::type_info::operator== constexpr" . ^ Daniil Goncharov (2022-06-25)."A more constexpr bitset" (PDF) . ^ Andreas Fertig (2021-11-06)."Making std::unique_ptr constexpr" (PDF) . ^ Edward J. Rosten; Oliver J. Rosten (2021-11-12)."constexpr for <cmath> and <cstdlib>" (PDF) . ^ Daniil Goncharov; Alexander Karaev (2021-09-18)."Add Constexpr Modifiers to Functions to_chars and from_chars for Integral Types in <charconv> Header" (PDF) . ^ Juan Alday (2020-10-12)."A proposal for a type trait to detect scoped enumerations" (PDF) . ^ Timur Doumler; Vittorio Romeo (2022-11-11)."A trait for implicit lifetime types" (PDF) . ^ Tim Song (2021-10-13)."A type trait to detect reference binding to temporary" . ^ Justin Bassett (2022-07-02)."Move-only types for equality_comparable_with, totally_ordered_with, and three_way_comparable_with" (PDF) . ^a b Corentin Jabot; Eric Niebler; Casey Carter (2022-01-21)."Conversions from ranges to containers" (PDF) . ^ Christopher Di Bella (2021-02-19)."starts_with and ends_with" . ^ Christopher Di Bella (2021-04-16)."std::ranges::contains" . ^ Zach Laine (2022-06-17)."find_last" (PDF) . ^ Tim Song (2021-12-05)."ranges::iota, ranges::shift_left, and ranges::shift_right" . ^ Barry Revzin (2022-04-22)."ranges::fold" . ^ Tim Song (2021-06-11)."zip" . ^ Barry Revzin (2022-01-28)."views::join_with" . ^ Tim Song (2021-12-05)."Windowing range adaptors: views::chunk and views::slide" . ^ Tim Song (2021-11-19)."views::chunk_by" . ^ Barry Revzin (2022-02-14)."views::as_rvalue" . ^a b Barry Revzin (2022-06-17)."cbegin should always return a constant iterator" . ^ Michał Dominiak (2022-07-13)."views::repeat" . ^ Christopher Di Bella; Tim Song (2022-07-08)."stride_view" . ^ Sy Brand; Michał Dominiak (2022-07-13)."views::cartesian_product" . ^ Corentin Jabot (2022-12-07)."views::enumerate" (PDF) . ^ David Olsen (2022-04-22)."Ranges iterators as inputs to non-Ranges algorithms" . ^ Michał Dominiak (2022-07-13)."Relaxing range adaptors to allow for move only types" . ^ Ville Voutilainen (2022-11-12)."Making multi-param constructors of views explicit" . ^ JeanHeyd Meneide; Todor Buyukliev; Isabella Muerte (2021-04-15)."out_ptr - a scalable output pointer abstraction" . ^ Jonathan Wakely; Chris Kennelly (2021-01-22)."Providing size feedback in the Allocator interface" . ^ Timur Doumler; Richard Smith (2022-07-15)."Explicit lifetime management" (PDF) . ^ Pablo Halpern (2023-02-08)."Disallow User Specialization of allocator_traits" . ^ Wim Leflere; Paul Fee (2020-06-13)."string contains function" . ^ Yuriy Chernyshov (2020-09-06)."A Proposal to Prohibit std::basic_string and std::basic_string_view construction from nullptr" . ^ Corentin Jabot (2021-03-17)."Range constructor forstd::string_view 2: Constrain Harder" (PDF) . ^ Chris Kennelly; Mark Zeren (2021-09-14)."basic_string::resize_and_overwrite" . ^ "std::string::substr() &&" .^ "Formatting Ranges" . 16 May 2022.^ Barry Revzin (2022-07-15)."Improve default container formatting" . ^ Corentin Jabot; Victor Zverovich (2023-02-09)."Formatting thread::id and stacktrace" (PDF) . ^ Alexey Gorgurov; Antony Polukhin (2020-09-16)."A Proposal to add stacktrace library" . ^ "Formatted output" .^ Peter Sommerlad (2021-02-26)."A strstream replacement using span<charT> as buffer" (PDF) . ^ "Support exclusive mode for fstreams" .^ Bryce Adelstein Lelbach (2021-09-25)."Printing volatile Pointers" . ^ "MDSPAN" . 13 July 2022.^ "index_type & size_type in mdspan" (PDF) .^ "mdspan: renamepointer andcontiguous" . 15 June 2022.^ "Add the missingempty tomdspan" .^ "A Standard flat_map" (PDF) .^ "A Standard flat_set" (PDF) .^ Arthur O'Dwyer; Mike Spertus (2021-03-14)."Stop overconstraining allocators in container deduction guides" . ^ Konstantin Boyarinov; Sergey Vinogradov; Ruslan Arutyunyan (2020-12-15)."Heterogeneous erasure overloads for associative containers" . ^ Corentin Jabot (2021-03-05)."Iterators pair constructors for stack and queue" (PDF) . ^ Nevin Liber (2021-03-19)."Require span & basic_string_view to be TriviallyCopyable" (PDF) . ^ Hans-J. Boehm (2020-10-23)."P0943R6: Support C atomics in C++" . ^ Steve Downey; Zach Laine; Tom Honermann; Peter Bindels; Jens Maurer (2021-04-12)."C++ Identifier Syntax using Unicode Standard Annex 31" . ^ Erich Keane (2020-07-02)."Allow Duplicate Attributes" (PDF) . ^ Barry Revzin (2021-09-14)."Change scope of lambda trailing-return-type" . ^ "The Equality Operator You Are Looking For" . 2022-01-13.^ "De-deprecating volatile compound operations" (PDF) .^ "Core Language Working Group NB comment resolutions for the November, 2022 meeting : 2654. 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Retrieved2024-12-09 .^ "[basic.stc.dynamic.safety]" .timsong-cpp.github.io . Retrieved2024-12-09 .^ JF Bastien; Alisdair Meredith (2021-04-16)."Removing Garbage Collection Support" . ^ Jens Maurer (2021-04-12)."Mixed string literal concatenation" . ^ "Remove non-encodable wide character literals and multicharacter wide character literals" (PDF) .^ CJ Johnson (2021-11-22)."Deprecate std::aligned_storage and std::aligned_union" (PDF) . ^ Matthias Kretz (2022-11-08)."Deprecate numeric_limits::has_denorm" (PDF) . ^ "Programming Languages — Technical specification for C++ extensions for concurrency 2" (PDF) .^ "C++ Support in Clang" .^ "C++ Standards Support in GCC - GNU Project" .^ Ranns, Nina (2020-11-19)."WG21 2020-11 Virtual Meeting: Minutes of Meeting" (PDF) . ^ Ranns, Nina (2021-02-22)."WG21 2021-02 Virtual Meeting: Minutes of Meeting" (PDF) . ^ Alexey Dmitriev; Howard Hinnant (2020-10-22)."Relax Requirements for time_point::clock" . ^ Tim Song (2020-11-13)."Locks lock lockables" . ^ Ranns, Nina (2021-06-07)."WG21 2021-06 Virtual Meeting Minutes of Meeting" (PDF) . ^ Ranns, Nina (2021-10-04)."WG21 2021-10 Virtual Meeting Minutes of Meeting" (PDF) . ^ "GCC 12 Adds Support For New #elifdef #elifndef Directives" .phoronix . May 12, 2021.Archived from the original on December 27, 2022.^ Steve Downey (2021-06-14)."Add a pmr alias for std::stacktrace" . ^ Giuseppe D'Angelo (2021-06-28)."Add a conditional noexcept specification to std::exchange" . ^ Tim Song (2021-08-06)."Cleaning up integer-class types" . ^ Thomas Köppe (2021-06-11)."Clarifying the status of the "C headers" . ^ Ranns, Nina (2022-02-07)."WG21 2022-02 Virtual Meeting: Minutes of Meeting" (PDF) . ^ Ranns, Nina (2022-08-09)."WG21 2022-07 Virtual Meeting: Minutes of Meeting" (PDF) . ^ Ranns, Nina (2022-12-05)."WG21 2022-11 Hybrid Meeting: Minutes of Meeting" (PDF) . ^ Victor Zverovich (2022-11-08)."Should the output of std::print to a terminal be synchronized with the underlying stream?" . ^ Ranns, Nina (2023-03-06)."WG21 2023-02 Hybrid Meeting: Minutes of Meeting" (PDF) . ^ Corentin Jabot (2023-02-09)."Referencing The Unicode Standard" (PDF) . ^ Tim Song (2023-01-31)."Stashing stashing iterators for proper flattening" .
