# Trait core::ops::SubAssign 1.8.0 [−] [src]

    #[lang = "sub_assign"]
    pub trait SubAssign<Rhs = Self> {
        fn sub_assign(&mut self, rhs: Rhs);
    }

The `SubAssign` trait is used to specify the functionality of `-=`.

# 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)]
    struct Point {
        x: i32,
        y: i32,
    }

    impl SubAssign for Point {
        fn sub_assign(&mut self, other: Point) {
            *self = Point {
                x: self.x - other.x,
                y: self.y - other.y,
            };
        }
    }

    impl PartialEq for Point {
        fn eq(&self, other: &Self) -> bool {
            self.x == other.x && 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});Run

## Required Methods

### `fn sub_assign(&mut self, rhs: Rhs)`

The method for the `-=` operator

## Implementors

- `impl SubAssign for Wrapping<usize>`
- `impl SubAssign for Wrapping<u8>`
- `impl SubAssign for Wrapping<u16>`
- `impl SubAssign for Wrapping<u32>`
- `impl SubAssign for Wrapping<u64>`
- `impl SubAssign for Wrapping<u128>`
- `impl SubAssign for Wrapping<isize>`
- `impl SubAssign for Wrapping<i8>`
- `impl SubAssign for Wrapping<i16>`
- `impl SubAssign for Wrapping<i32>`
- `impl SubAssign for Wrapping<i64>`
- `impl SubAssign for Wrapping<i128>`
- `impl SubAssign for usize`
- `impl SubAssign for u8`
- `impl SubAssign for u16`
- `impl SubAssign for u32`
- `impl SubAssign for u64`
- `impl SubAssign for u128`
- `impl SubAssign for isize`
- `impl SubAssign for i8`
- `impl SubAssign for i16`
- `impl SubAssign for i32`
- `impl SubAssign for i64`
- `impl SubAssign for i128`
- `impl SubAssign for f32`
- `impl SubAssign for f64`

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