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# core::ops::arith::SubAssign

The subtraction assignment operator `-=`.

## Signature

```rust theme={null}
pub trait SubAssign
```

## Trait functions

### sub\_assign

Performs the `-=` operation.

#### Signature

```rust theme={null}
fn sub_assign(ref self: Lhs, rhs: Rhs)
```

#### Examples

```rust theme={null}
let mut x: u8 = 3;
x -= x;
assert!(x == 0);
```