Miss Dada  🏳️‍⚧️

does &* on the Rc help

yeah, just, idk why I'm surprised given the type system rules but this caught me off guard

It's just not an impl that anyone thought to write explicitly. Auto-deref isn't ever used when satisfying traits, so unless there's an explicit `PartialEq<Rc<String>> for str`, it'll fail.

ahh

yeah it makes more sense when you realise it's invoking a function of two arguments, and Deref doesn't mean that fn will try to find a common deref target to make the type system happy

Nah, it can pick one. It's just because traits are involved (and there are multiple deref targets to choose from, though it could just pick the first in the chain tbh) https://play.rust-lang.org/?version=stable&mode=debug&edition=2018&gist=00257fc8db0914a33c6e000a038111e8 …

basically, http://foo.bar () - style autoderef works in generic situations, but the kind of autoderef where &*** is automatically applied to things to coerce them is far more limited: if it's generic (or even if relying too heavily on inference) it won't work

Yup, which is kinda silly because the same rules used to decide which type is the receiver of `.bar` can be applied whenever `&` is used for argument passing