On 12/4/20 10:48 AM, JeanHeyd Meneide via SG16 wrote:
Dear SG16 and C/C++ Liaison Group,

     N2594 - https://thephd.github.io/_vendor/future_cxx/papers/C%20-%20Mixed%20Wide%20String%20Literal%20Concatenation.html
- was accepted by WG14 this meeting and we just adjourned. This means
both languages have feature parity in this regards! 🎉
Excellent!  Nice work!


     WG14 also wants to look into -- after removing it -- spending
some time coming up with well-defined combination mechanism. We would
like to have ill-formedness (C++) / constraint violations (C) if the
conversion to the final chosen encoding do not work, to give people
good guarantees above e.g. synthesizing Unicode into an wide string
literal or synthesizing wide string data into Unicode literals.

Was any particular use case discussed?  Or just a general preference to, given something like this:

#define NAME u8"foo"
#define VERSION "5"

void emit(const char16_t*);

to be able to do something like this:

emit(u"" NAME "-" VERSION);

as opposed to having to do conversions and concatenations at run-time?

     (Also, I forgot to ask if they wanted to do something similar to
P1041 - https://wg21.link/p1041 - yet...)

That would be good to get on the agenda for the next WG14 meeting.  It would be great if we can start making progress on all of the following issues!  My understanding is that any proposals targeting C2X must be proposed by August 27th, 2021.