I don't think Rust has any one answer to a UI problem, since the UI story is basically the wild west right now. Everyone is doing something a little different.

I didn't mean to imply that, just that when I see people complain about the ergonomics of the language and point to using a bunch of Rc<RefCell<T>> stuff usually smells funny, it implies to me that you're either trying to use OO or control flow architectures and patterns, where the type system is able to handle the edge cases that you'd need to think about anyway. There are nicer alternatives, especially in terms of data flow architectures.

And I don't know what you mean by "indexes" in this context or which talk you're referring to, do you have any more details or a link? Google isn't finding me anything.

Catherine is relatively known in the Rust community, hence why I didn't mention anything else.

Here is her keynote talk at Rust Conf 2018.

https://youtu.be/aKLntZcp27M

Ah ok had to skim through the slides a bit, I think you meant to use the phrase "generational indexes" which is why googling didn't help me. This project was more helpful for my understanding:

https://github.com/fitzgen/generational-arena

I'm not sure what your ultimate point was though? You don't have to use anything like that in normal Rust code

Only if you understand by normal Rust code, CLI apps.

If we are talking about graphical applications, that would be a common usage.