Builder pattern in Rust: self vs. &mut self, and method vs. associated function

[quinedot]

@jbe

As the first type parameter is only used for a PhantomData , I think the compiler should not complain, right? Could this be considered a bug or feature request?

It wasn't the source of your error, but PhantomData being owning is this conversation again. It's either an intentional "bug" (that makes more things sound, not less) or incorrect documentation, depending on your POV.