Generics

Generic Structs

use std::fmt::Display;

struct Point<T> {
    x: T,
    y: T,
}

impl<T> Point<T> {
    fn x(&self) -> &T {
        &self.x
    }
}

impl Point<f32> {
    // specify constraints on generic types
    fn distance_from_origin(&self) -> f32 {
        (self.x.powi(2) + self.y.powi(2)).sqrt()
    }
}

impl<T: Display + PartialOrd> Point<T> {
    // use Trait Bounds to Conditionally Implement Methods
    fn cmp_display(&self) {
        if self.x >= self.y {
            println!("The largest member is x = {}", self.x);
        } else {
            println!("The largest member is y = {}", self.y);
        }
    }
}

fn main() {
    let p = Point { x: 5, y: 10 };

    println!("p.x = {}", p.x());
}

See Also

• Structs.
• Enums.
• Functions.
• Traits.
• Rust Patterns.