w") construction from [ ` nullptr ` ](/w/cpp/language/nullptr "cpp/language/nullptr") |  [ P2166R1 ](https://wg21.link/P2166R1) |  12  |  13  |  19.30*  |  13.1.6*  |  |  |   
[ ` std::invoke_r() ` ](/w/cpp/utility/functional/invoke "cpp/utility/functional/invoke") |  [ P2136R3 ](https://wg21.link/P2136R3) |  12  |  17  |  19.31*  |  15.0.0*  |  |  |   
Range [ constructor ](/w/cpp/string/basic_string_view/basic_string_view "cpp/string/basic string view/basic string view") for  [ std::basic_string_view ](/w/cpp/string/basic_string_view "cpp/string/basic string view") |  [ P1989R2 ](https://wg21.link/P1989R2) |  11  |  14  |  19.30*  |  14.0.3*  |  |  |   
Default template arguments for  [ std::pair ](/w/cpp/utility/pair "cpp/utility/pair") 's forwarding [ constructor ](/w/cpp/utility/pair/pair "cpp/utility/pair/pair") |  [ P1951R1 ](https://wg21.link/P1951R1) |  14  |  14  |  19.30*  |  14.0.3*  |  |  |   
Remove Garbage Collection and Reachability-Based Leak Detection ( [ library support ](/w/cpp/memory#Garbage_collector_support "cpp/memory") )  |  [ P2186R2 ](https://wg21.link/P2186R2) |  12  |  14  |  19.30*  |  14.0.3*  |  |  |   
zip: [ ` views::zip ` ](/w/cpp/ranges/zip_view "cpp/ranges/zip view") , [ ` views::zip_transform ` ](/w/cpp/ranges/zip_transform_view "cpp/ranges/zip transform view") , [ ` views::adjacent ` ](/w/cpp/ranges/adjacent_view "cpp/ranges/adjacent view") , and [ ` views::adjacent_transform ` ](/w/cpp/ranges/adjacent_transform_view "cpp/ranges/adjacent transform view") |  [ P2321R2 ](https://wg21.link/P2321R2) |  13  |  15 (partial)*  |  19.33*  (partial)*  *  *    
19.37*  |  14.0.3*  |  |  |   
Heterogeneous erasure overloads for associative containers  |  [ P2077R3 ](https://wg21.link/P2077R3) |  |  |  19.32*  |  |  |  |   
[ ` std::byteswap() ` ](/w/cpp/numeric/byteswap "cpp/numeric/byteswap") |  [ P1272R4 ](https://wg21.link/P1272R4) |  12  |  14  |  19.31*  |  14.0.3*  |  |  |   
[ Printing ](/w/cpp/io/basic_ostream/operator_ltlt "cpp/io/basic ostream/operator ltlt") volatile  T  *  |  [ P1147R1 ](https://wg21.link/P1147R1) |  11.3  |  14  |  19.31*  |  14.0.3*  |  |  |   
[ ` basic_string::resize_and_overwrite() ` ](/w/cpp/string/basic_string/resize_and_overwrite "cpp/string/basic string/resize and overwrite") |  [ P1072R10 ](https://wg21.link/P1072R10) |  12  |  14  |  19.31*  |  14.0.3*  |  |  |   
Monadic operations for  [ std::optional ](/w/cpp/utility/optional "cpp/utility/optional") |  [ P0798R8 ](https://wg21.link/P0798R8) |  12  |  14  |  19.32*  |  14.0.3*  |  |  |   
[ ` std::move_only_function ` ](/w/cpp/utility/functional/move_only_function "cpp/utility/functional/move only function") |  [ P0288R9 ](https://wg21.link/P0288R9) |  12  |  |  19.32*  |  |  |  |   
Add a conditional noexcept specification to  [ std::exchange ](/w/cpp/utility/exchange "cpp/utility/exchange") |  [ P2401R0 ](https://wg21.link/P2401R0) |  12  |  14  |  19.25*  |  14.0.3*  |  |  |   
Require [ ` std::span ` ](/w/cpp/container/span "cpp/container/span") & [ std::basic_string_view ](/w/cpp/string/basic_string_view "cpp/string/basic string view") to be [ TriviallyCopyable  ](/w/cpp/named_req/TriviallyCopyable "cpp/named req/TriviallyCopyable") |  [ P2251R1 ](https://wg21.link/P2251R1) |  Yes  |  Yes  |  Yes  |  Yes  |  |  |   
Clarifying the status of the “C headers”  |  [ P2340R1 ](https://wg21.link/P2340R1) |  Yes  |  Yes  |  Yes  |  Yes  |  |  |   
[ ` <expected> ` ](/w/cpp/header/expected "cpp/header/expected") |  [ P0323R12 ](https://wg21.link/P0323R12)   
[ P2549R1 ](https://wg21.link/P2549R1) |  12  |  16  |  19.33*  |  15.0.0*  |  |  |   
constexpr for [ ` <cmath> ` ](/w/cpp/header/cmath "cpp/header/cmath") and [ ` <cstdlib> ` ](/w/cpp/header/cstdlib "cpp/header/cstdlib") |  [ P0533R9 ](https://wg21.link/P0533R9) |  4.6  (partial)*  |  |  |  |  |  |   
[ ` std::unreachable() ` ](/w/cpp/utility/unreachable "cpp/utility/unreachable") |  [ P0627R6 ](https://wg21.link/P0627R6) |  12  |  15  |  19.32*  |  14.0.