I'm trying to better understand some borrowed code by recreating a minimal version that I can follow. But I have no idea if these patterns are sane or idiomatic:

V1: (similar to what I'm using now)
Playground: Link
Reference: Design Patterns in Rust: Mediator
Reference: Wasm_Bindgen: TODO MVC
Has:

• Rc<RefCell<Option<T>>> in the mediator field
• &*self.leaf_1.borrow_mut()

V2: (modifed example from rust docs)
Playground: Link
Reference: Rust Docs: Reference Cycles Can Leak Memory
Has:

• RefCell<Rc<Option<T>>> in the branch field
• Weak, Downgrade/Upgrade
• &**self.leaf_1.borrow_mut()

Both versions compile and lint OK.

What I need help with:

1. The Rc+RefCell / RefCell+Rc thing. -- I don't know if one structure is better than the other for the fields in the Mediator / Branch, or if the ordering will cause problems down the line.
2. &* and &** to get references to the Rc items: -- It took an embarrasing amout of time to figure out how to get these references - but the double / triple operators makes me think I'm not accessing these items properly / idiomatically / explicitly.

Are there any rules of thumb I should be following when constucting these Rc items and getting references to them?

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