Comment by terts
3 months ago
Hi! So for Roto, our introspection needs are actually fairly limited. We only need the `TypeId`, the type name, the size and the alignment. which Rust can give us without any additional traits. It's not possible currently to - for example - access struct fields and enum variants. That is something that I plan to add, but that might require a crate like `bevy_reflect` or `facet`.
Rust is giving me just enough information to pull the current version of. More powerful introspection/reflection is not possible without derive macros. If you're ok with derive macros though, you could look into the 2 crates I mentioned.
Hope that answers your question!
Did you go through many iterations on the API of the registration? If so, which designs did you disqualify and why?
Not many iterations, but a lot of head scratching was involved haha.
I decided against using a trait and a derive macro because I wanted to avoid running into Rust's orphan rule. We have a crate called routecore where most of our types are declared and then a separate crate called Rotonda which uses those types and uses Roto. I wanted Rotonda to be able to register routecore types.
That's also the downside of the current reflection crates; they require each type to have a derive macro.