Rust for C-Programmers

2.10 Traits

Traits define shared behavior (similar to interfaces in other languages). A trait declares method signatures, and types implement those methods.

2.10.1 Declaring a Trait

trait Drawable {
    fn draw(&self);
}

2.10.2 Implementing a Trait

struct Circle;

impl Drawable for Circle {
    fn draw(&self) {
        println!("Drawing a circle");
    }
}

2.10.3 Using Traits

trait Drawable {
    fn draw(&self);
}

struct Circle;

impl Drawable for Circle {
    fn draw(&self) {
        println!("Drawing a circle");
    }
}

fn main() {
    let c = Circle;
    c.draw();
}

2.10.4 Comparison with C

C does not have a built-in concept of traits or interfaces. Often, function pointers or structs of function pointers (vtables) serve a similar purpose.