#![allow(dead_code, deprecated, unused_variables, unused_mut)]
use std::ops::DivAssign;
#[derive(Debug, PartialEq)]
struct Frequency {
    hertz: f64,
}
impl DivAssign<f64> for Frequency {
    fn div_assign(&mut self, rhs: f64) {
        self.hertz /= rhs;
    }
}
fn main() {
    let mut frequency = Frequency { hertz: 200.0 };
    frequency /= 4.0;
    assert_eq!(Frequency { hertz : 50.0 }, frequency);
}