Sometimes I wonder if this pure search for being "idiomatic" is worth the effort. On paper yes, more idiomatic code is almost always a good thing, it feels more natural to create code in a way the language was designed to be used. But it practice, you don't get any points for being more idiomatic and your code isn't necessarily going to be safer either (smart pointers are often "good enough"). I'm fine using references to pass parameters to function and I love the idea to "force" the programmer to organize objects in a tree way (funny enough I was already doing that in C++), but I'll take a Rc rather than a lifetimed reference as a field in a structure any day. That shit becomes unreadable fast!

EDIT: but I love cargo clippy! It tells me what to change to get more idiomatic points. Who knows why an if/then/else is better than a match for two values, but clippy says so, and who am I to question the idiomatic gods?