trpl-zh-cn/listings/ch07-managing-growing-projects/listing-07-07/src/lib.rs

// ANCHOR: here
mod front_of_house {
    pub mod hosting {
        pub fn add_to_waitlist() {}
    }
}

// -- snip --
// ANCHOR_END: here
pub fn eat_at_restaurant() {
    // 绝对路径
    crate::front_of_house::hosting::add_to_waitlist();

    // 相对路径
    front_of_house::hosting::add_to_waitlist();
}