C++23

Nov 2020 – Issaquah 2023 · N4950 (final draft) · ISO/IEC 14882:2024
188papers adopted
45features touched
8plenaries
← C++20C++26 →Show only C++23 on the map

Language

17 features
Character sets & encodings (C++23)13 papersSmall language features (C++23)8 papersconstexpr relaxations (C++23)4 papersLambda improvementsalso C++294 papersObject lifetime & unionsalso C++263 papersPreprocessor (C++23)3 papersAttributesalso C++262 papersCore wording overhaulsalso C++262 papersDeducing this2 papersif consteval2 papersModules fixesalso C++262 papersstatic operator() / operator[]2 papersCTAD improvementsalso C++261 paperExtended floating-point types1 paperInitialization & value categoriesalso C++26, C++291 paperMultidimensional subscript1 paperTemplates & concepts (core)also C++26, C++291 paper

Library

26 features · 2 housekeeping
Ranges: C++20 defect fixes19 papersRanges: new views & algorithms (C++23)18 papersstd::format & std::print (C++23)13 papersUtilities & type traitsalso C++268 papersStrings & string_viewalso C++267 papersLibrary constexpr-ification (C++23)6 papersmdspanalso C++26, C++295 papersDeprecations & removalsalso C++264 papersiostreams & file streamsalso C++26, C++294 papersSmart pointers & allocatorsalso C++264 paperstuple, pair & variantalso C++264 papersstd::expectedalso C++26, C++293 papersC compatibilityalso C++26, C++292 papersConcurrency utilitiesalso C++26, C++292 papersflat_map / flat_setalso C++26, C++292 papersstd::generator2 papersstd::stacktrace2 papersType-erased callablesalso C++262 papersAssociative container lookupsalso C++261 paperAtomics & memory modelalso C++26, C++291 paperBit operationsalso C++291 paperchrono & ratioalso C++261 paperExceptions & exception_ptralso C++261 paperFreestanding libraryalso C++261 paperStandard library modules1 paperstd::optionalalso C++261 paperCore & Library issue resolutionsalso 6 others19 papersNB-comment omnibus & housekeepingalso 5 others2 papers

Papers per plenary

Virtual Jul 2022 was the busiest plenary: 57 papers adopted into C++23.

VirtualNov 202011VirtualFeb 20219VirtualJun 202128VirtualOct 202129VirtualFeb 202216VirtualJul 202257KonaNov 202216IssaquahFeb 202322

Idioms in C++23

what changed in practice · from the Atlas
Parameter passingCore semanticsOwnership & lifetimesCore semanticsValue vs. reference semanticsCore semanticsMove semanticsCore semanticsInitializationCore semanticsConst & constexpr correctnessCore semanticsClass designDesignError handlingDesignPolymorphism choiceDesignAPI boundaries & vocabulary typesDesignCustomization pointsGeneric & compile-timeConstraint styleGeneric & compile-timeNamed idiomsGeneric & compile-timeAlgorithms & ranges over raw loopsCode-levelCasting disciplineCode-levelConcurrency idiomsCode-levelPhysical designCode-levelCoroutine machineryCompile-time & language mechanicsAsync compositionCompile-time & language mechanicsUB & object lifetimeCompile-time & language mechanicsDeclaration styleCompile-time & language mechanicsLambda idiomsCompile-time & language mechanicsName lookup hygieneCompile-time & language mechanicsAllocator awarenessMemory & performancePerformance idiomsMemory & performanceCode-size controlMemory & performanceGlobal state & init orderMemory & performanceString handlingText, numbers, timeInteger hygieneText, numbers, timechrono disciplineText, numbers, timeComparators & hashingText, numbers, timeC interop & ABIBoundaries & practiceFreestanding & embedded subsetBoundaries & practiceFeature detection & migrationBoundaries & practiceTooling-encoded idiomBoundaries & practice