pub trait SubAssign<Rhs = Self> {
fn sub_assign(&mut self, rhs: Rhs);
}Expand description
The subtraction assignment operator -=.
Examples
This example creates a Point struct that implements the SubAssign
trait, and then demonstrates sub-assigning to a mutable Point.
use std::ops::SubAssign;
#[derive(Debug, Copy, Clone, PartialEq)]
struct Point {
x: i32,
y: i32,
}
impl SubAssign for Point {
fn sub_assign(&mut self, other: Self) {
*self = Self {
x: self.x - other.x,
y: self.y - other.y,
};
}
}
let mut point = Point { x: 3, y: 3 };
point -= Point { x: 2, y: 3 };
assert_eq!(point, Point {x: 1, y: 0});