It's been a while, but I tried implementing a trait that took `&self` with several different types. One such type was an integer type, so I had to pass by reference. It's probably not a big deal, but there are many things like this that seem to prefer you move or reference rather than copy.
I think it would be better for all traits to implement their methods on `self` and then the caller can choose whether the type that implements the trait is `i64` or `&i64` (instead of the trait being prescriptive about the type, which largely defeats the purpose of traits to begin with).
That said, I'm not very experienced in Rust, so I expect someone can correct me about why this is a Very Bad Idea.
I think it would be better for all traits to implement their methods on `self` and then the caller can choose whether the type that implements the trait is `i64` or `&i64` (instead of the trait being prescriptive about the type, which largely defeats the purpose of traits to begin with).
That said, I'm not very experienced in Rust, so I expect someone can correct me about why this is a Very Bad Idea.