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Reflection for C++26

(isocpp.org)
196 points svlasov | 3 comments | 30 Jun 24 11:26 UTC | HN request time: 0s | source
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stefanos82 ◴[01 Jul 24 22:41 UTC] No.40851614[source]▶
Can I ask a naive question that consists of two parts and please don't flame me? lol

  * What type of problems static reflection could solve, in general?
  * Are there specific cases and / or situations where static reflection could resolve such case, even simplify an unnecessary complexity?
replies(8): >>40851661 #>>40851675 #>>40851709 #>>40851795 #>>40851942 #>>40852552 #>>40853159 #>>40853615 #
quotemstr ◴[01 Jul 24 22:49 UTC] No.40851675[source]▶
> What type of problems static reflection could solve, in general?

Imagine making a plain

    struct Point { float x; float y; };
and wanting to serialize it to JSON without further ceremony
replies(2): >>40851792 #>>40853917 #
1. sankhao ◴[02 Jul 24 06:01 UTC] No.40853917[source]▶
This is doable in c++20 https://github.com/stephenberry/glaze
replies(1): >>40854242 #
2. _flux ◴[02 Jul 24 07:11 UTC] No.40854242[source]▶
That's pretty neat! What's the C++20 feature that enables this?
replies(1): >>40855636 #
3. gpderetta ◴[02 Jul 24 11:40 UTC] No.40855636[source]▶
From a quick look, generalized constexpr evaluation, but in practice it relies on parsing non-portable decorated function names from things like source location. An ugly, slow, but effective hack.