Re: [boost] [system] The new Boost.System is now ready

The new Boost.System is now complete, on the develop branch:

https://www.boost.org/doc/libs/develop/libs/system/

- header-only - even more constexpr than 1.68

https://pdimov.github.io/cpp-papers/P1195R0.html

- identifier-based category comparison

https://pdimov.github.io/cpp-papers/P1196R0.html

- message() into a caller-supplied buffer

https://pdimov.github.io/cpp-papers/P1197R0.html

- failed()

https://pdimov.github.io/cpp-papers/P1198R0.html

The plan is to merge it to master at some point if no breakage is encountered on develop, so that it can go into the next release.