Prague 2020

February 2020 plenary · adopted into C++20
44papers adopted
21features touched
← Belfast 2019Virtual 2020 →

Modules

5 papers
P1779R3ABI isolation for member functionsC++20P1815R2Translation-unit-local entitiesC++20P1857R3Modules dependency discoveryC++20P2109R0Disallow export import foo outside of module interfaceC++20P2115R0Merging of multiple definitions for unnamed unscoped enumerationsC++20

NB-comment omnibus & housekeeping

5 papers
P1963R0Fixing US 313C++20P1983R0Wording for GB301, US296, US292, US291, and US283C++20P2103R0Core Language Changes for NB Comments at the February, 2020 (Prague) MeetingC++20P2106R0Alternative wording for GB315 and GB316C++20P2113R0Proposed resolution for 2019 comment CA 112C++20

Ranges

5 papers
P1243R4Rangify new algorithmsC++20P1739R4Avoid template bloat for safe_ranges in combination with "subrange-y" view adaptorsC++20P1970R2Consistency for size functions: add ranges::ssizeC++20P1994R1elements_view needs its own sentinelC++20P2091R0Issues with range access customization point objectsC++20

Concepts

3 papers
P2092R0Disambiguating *nested-requirement*sC++20P2101R0'Models' subsumes 'satisfies'C++20P2104R0Disallow changing concept valuesC++20

Core & Library issue resolutions

3 papers
P2051R0C++ Library Issues to be moved in PragueC++20P2108R0Core Language Working Group "ready" issues for the February, 2020 (Prague) meetingC++20P2117R0C++ Standard Library Issues Resolved Directly In PragueC++20

Library specification rewrite (Mandates/Constraints)

3 papers
P1460R1Mandating the Standard Library: Clause 20 - Utilities libraryC++20P1973R1Rename _default_init functionsC++20P2045R1Missing *Mandates:* for the standard libraryC++20

Bit manipulation & numeric utilities

2 papers
P0586R2Safe integral comparisonsC++20P1956R1On the names of low-level bit manipulation functionsC++20

Calendars & time zones

2 papers
P1981R0Rename leap to leap_secondC++20P1982R0Rename link to time_zone_linkC++20

Standard library concepts

2 papers
P1964R2Wording for *boolean-testable*C++20P2102R0Make 'implicit expression variations' more explicitC++20

std::span

2 papers
P1976R2Fixed-size span construction from dynamic rangeC++20P2116R0Remove tuple-like protocol support from fixed-extent spanC++20

Three-way comparison (<=>)

2 papers
P2002R1Defaulted comparison specification cleanupsC++20P2085R0Consistent defaulted comparisonsC++20

Attributes (C++20)

1 paper
P1908R1Reserving attribute namespaces for future useC++20

constexpr expansion (C++20)

1 paper
P1937R2Fixing inconsistencies between constexpr and consteval functionsC++20

Containers & algorithms (C++20)

1 paper
P1115R3Improving the return value of erase-like algorithms, part 2: free erase[_if]C++20

Coroutines

1 paper
P2107R0Copy semantics of coroutine parametersC++20

CTAD improvements (C++20)

1 paper
P2082R1Fixing CTAD for aggregatesC++20

Deprecations & removals (C++20)

1 paper
P1831R1Deprecating volatile: libraryC++20

Implicit object creation

1 paper
P0593R6Implicit creation of objects for low-level object manipulationC++20

Lambda improvements (C++20)

1 paper
P2095R0Resolve lambda init-capture pack grammarC++20

Small language features (C++20)

1 paper
P1957R2Converting from T* to bool should be considered narrowingC++20

std::format

1 paper
P1868R2🦄 width: clarifying units of width and precision in std::formatC++20