Prefer super or crate for internal module references

[huachaohuang]

We can refer to modules in the same crate in different ways. For example, given a crate like this:

src/
  lib.rs
  a.rs
  b.rs

a can import trait B in b as crate::b::B or super::b::B. And if B is pub use in lib.rs, a can also refer B as crate::B. All these work, but it is troublesome to think about which way to go every time. So I think it will be better if we have a guideline about this.

My opinion is that we should prefer referring things relatively using super::b::B because:

• It doesn't assume if B is public or not
• When refactoring file structure, for example, if we want to move a.rs and b.rs to a sub-directory, the code still works

[dtolnay]

This makes no difference to the API of a crate so I believe it would be off topic for the API Guidelines. This project is not an all-purpose Rust code style guide.

[huachaohuang]

Got it. Any recommended place for this discussion?

[tisonkun]

@huachaohuang I think it's https://github.com/rust-dev-tools/fmt-rfcs .

Reference

• https://github.com/rust-lang/rust-guidelines
• https://doc.rust-lang.org/1.0.0/style/

[tisonkun]

And here it is rust-lang/style-team#167.