Hello all,

I want to help make injection happen for C++29 and would really appreciate
some context and history before delving in.
I read online that the favoured approach today is of token sequences from
P3294R2 <http://wg21.link/P3294R2>, instead of fragments from P2237R0
<http://wg21.link/P2237R0>.

I understand the token sequences approach is very powerful, but it is not
ideal due to it being unstructured.

What happened to the fragments approach? It looked very promising. I found
only two technical discussions on the subject:
1. The comparison part of P3294R3. Specifically the problem described in
section 4.11.
2. Discussions <https://lists.isocpp.org/sg7/2020/10/0042.php> on the SG7
reflector from 2020 about P2237 (in which it seems fragments is prefered).

Note I am not on the committee yet, I don't have access to the wiki.

>From my understanding, the main technical problem with fragments is "the
composition of fragments is awkward because we can only inject valid
fragments".

If this is the only major issue, I think it can be solved without
abandoning the approach completely. I can elaborate if desired (and write a
paper if this is deemed valuable).

Is there more to it than this problem?

Sincerely,
Omer Rosler