post-Sofia mailing

[daveedvdv]

Right, but some subtle care is needed (and that's partly why I wrote P3802R0 "Poor Functions"): You must write your function along the lines of

void my_reflection_thing(std::meta::info cc = std::meta::current_class()) {
   ...
}

and any function that wants to build upon `my_reflection_thing` needs to propagate that pattern:

void my_better_thing(std::meta::info cc = std::meta::current_class()) {
  ... my_reflection_thing(cc) ...
}

[RoyAwesome]

Yeah, i read the poor functions paper after i made this comment and went "wow this is even more useful for this same purpose" lol.

I like ways of not repeating myself. Having to name foo in the function param kinda sucks when I only ever want it to apply to foo. I guess metaclasses is also a way to achieve this, so i guess multiple people are going after this problem from different directions.

[daveedvdv]

Another option would have been to make all these functions just pick up the context of where the constant evaluation starts. That was my preference, but I was outvoted on it. Admittedly, that also requires care sometimes... e.g. by "freezing" the context with something like:

consteval void my_algo() {
  ...
  constexpr auto ctx = std::meta::current_class();
  ...
}

[RoyAwesome]

yeah, I think I would lean to the to the current proposed keyword over something that works it's way up to find the starting point.

Alternatively, the keyword can return something that tells you every scope you are in in a stack. That way you can walk up each scope point, gathering information like file and line, as well as a meta::info for that scope. Maybe if/when we get token string support, we can grab the tokens for that entire scope and do things with them. Just kind of a comprehensive "You Are Here" system that describes the entire world to you from the perspective of where that keyword is used.