[adastra22]

Thank you. Now I understand the article. And the problem identified for type classes isn’t an issue in Rust. You’d return a ‘dyn Trait’ and be done. It means the object would have to be heap allocated, but that is already a given because you are wanting to define a function that can work with any type including future defined types. I guess Haskell doesn’t support the equivalent of trait objects for type classes?

I’m not trying to prove that rust is better or something. People who do that are annoying. It’s just weird to me that this is being presented as a fundamental and largely unsolved challenge when there is a simple solution at the heart of a widely deployed and well known language, which in turn stole it from elsewhere.

[naasking]

dyn traits have quite a few restrictions if I'm reading the docs right. Like, dispatchable functions can't even have type parameters [1]. I wouldn't exactly call that "solved", although maybe a language with traits and dyn traits that used GC wouldn't have such onerous restrictions.

[1] https://doc.rust-lang.org/reference/items/traits.html#dyn-co...