papers VS mp11

What's fun is, because everything is decided in papers, we can find out why! https://github.com/cplusplus/papers/issues/884

Accepted paper here: https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2022/p20...

> The proposed std::print function improves usability, avoids allocating a temporary std::string object and calling operator<< which performs formatted I/O on text that is already formatted. The number of function calls is reduced to one which, together with std::vformat-like type erasure, results in much smaller binary code (see § 13 Binary code).

Additionally,

> Another problem is formatting of Unicode text:

> std::cout << "Привет, κόσμος!";

> If the source and execution encoding is UTF-8 this will produce the expected output on most GNU/Linux and macOS systems. Unfortunately on Windows it is almost guaranteed to produce mojibake despite the fact that the system is fully capable of printing Unicode

See https://github.com/cplusplus/papers/issues/557

Bringing editions to C++ failed, and I am not aware of anyone trying to tackle the issues https://github.com/cplusplus/papers/issues/631

(I could be wrong though! I follow the committee more than you may guess, but not as much as to think I know everything about what's going on.)

GitHub would not be relevant in this respect because:

* It's owned by a (single) commercial corporation, Microsoft.

* There is censorship both by content and in some respects by country of origin.

* The code is closed.

but otherwise it's an interesting idea.

The C++ standardization committee uses GitHub to track papers submitted to them, see:

https://github.com/cplusplus/papers

There was no non-approval. The facility needs more work, and the authors (and the committee) were focusing on getting print/format done first. I hope that the paper will be worked on again in the future. We will be happy to review it once there is a revision (see github for history)

For more details on what we did at the 2023-06 Varna meeting, the [GitHub issue](https://github.com/cplusplus/papers/issues/328) associated with the paper has a summary.

You subscribe to the Github issue of the proposal: https://github.com/cplusplus/papers/issues

Mp11 is standalone, but if even that's too much Boost, you can always copy/paste mp_for_each (minus the workaround if you don't need it) and tuple_for_each.

Boost.Mp11 should be the starting point for these kinds of typelist shenanigans. There's a lot of implementation tricks in there to speed up compilation (e.g. mp_at_c uses the __type_pack_element you mention in its implementation):