use std::fmt::Debug;
trait HasArea {
fn area(&self) -> f64;
}
impl HasArea for Rectangle {
fn area(&self) -> f64 { self.length * self.height }
}
impl HasArea for Triangle {
fn area(&self) -> f64 { self.length * self.height }
}
#[derive(Debug)]
struct Rectangle { length: f64, height: f64 }
#[derive(Debug)]
struct Triangle { length: f64, height: f64 }
fn print_debug<T: Debug>(t: &T) {
println!("{:?}", t);
}
fn area<T: HasArea>(t: &T) -> f64 { t.area() }
fn main() {
let rectangle = Rectangle { length: 3.0, height: 4.0 };
let triangle = Triangle { length: 3.0, height: 4.0 };
print_debug(&rectangle);
println!("Area: {}", area(&rectangle));
print_debug(&triangle);
println!("Area: {}", area(&triangle));
}