Finding Your Way (use)

Last time we built rooms called modules. But how do you tell Rust exactly which room to look in? You give it directions — a path! 🗺️

A path is like an address. It says, “Start at the front door, go down the hall, into the kitchen, and grab the cook function.” Let’s learn how to write these directions, plus a handy shortcut to make them shorter.

A path is an address

A path names where something lives in your code. You spell it out with two dots :: between each step, starting from crate (that means “this whole crate, from the very top”).

Think of it like this… A path is like an address on a map. crate::kitchen::cook means: start at the top, go into the kitchen room, find cook. 🗺️

Writing the whole path every single time can feel long, especially if you use it a lot. That’s where our shortcut comes in.

The `use` shortcut

The word use makes a shortcut to something. After you use a path once, you can write just the short name instead of the whole long address. 🎉

New word use creates a shortcut to a path. It's like saving a place on a map so you can jump straight there without typing the full address again. 📌

Here we use the kitchen module, then call cook with the short name:

mod kitchen {
    pub fn cook() {
        println!("Sizzle! Dinner is ready. 🍳");
    }
}

use crate::kitchen::cook;

fn main() {
    cook();
    cook();
}

Thanks to use, we just wrote cook() instead of crate::kitchen::cook() every time. Much shorter, and still easy to read! 🙌

Ferris says: Lots of coders like to use the whole room, like use crate::kitchen;, and then call kitchen::cook(). That way you can still tell which room the code came from! 🦀

Try this! Add a second pub fn bake() inside the kitchen module that prints a baking message. Add another use line for it, then call bake() from main. Shortcuts everywhere! 🧁

Quick quiz

What does use do?

Yes! use creates a shortcut, so you can call the short name instead of the long path. 🎉

You learned… A path is an address like crate::kitchen::cook, and use makes a handy shortcut so you can write the short name. You've kept a big project tidy — high five! 🖐️ Next world: World 8: Collections, where we store whole groups of things together! 📚

A path is an address

The use shortcut

Quick quiz

The `use` shortcut