From Mastadon post.

Working my way through the #rust book. Little confused by something in the modules section. Can't quite fit the whole thing in one toot, so here's a gist: <here>

Short version, useing nested modules. Does this allow access to ancestor modules or not?

---

In the modules section, the author refers back to the "guessing game" section and shows this:

use rand::Rng;

fn main() {
    let secret_number = rand::thread_rng().gen_range(1..=100);
}

From this, I figure "oh ok. We've included Rng from the rand module. Then we use the thread_rng function which is in the rand module. I guess because we've useed rand::Rng we now have access to public things in the rand module?

But then, testing this out, I do this:

// src/main.rs
use module_test::foo::bar;

fn main() {
    println!("{}", foo::get_3());
    println!("{}", bar::get_5());
}

// src/lib.rs
pub mod foo {
    pub fn get_3() -> u32 { 3 }

    pub mod bar {
        pub fn get_5() -> u32 { 5 }
    }
}

This fails to compile with error: use of undeclared crate or module foo

So what gives? If I use foo::bar::baz, does that allow me to do things off of foo itself or not?

Seems like not. But if not, then how does the use rand::Rng allow us to then access rand::other_non_Rng_things?