Checking for integer overflow in Rust [duplicate]

Question

Is there a canonical way to explicitly check for integer overflow in Rust? I Googled around but couldn't find the answer.

Something like:

match add_or_overflow(x, y) {
  None    => println!("overflow!"),
  Some(z) => println!("{} + {} = {}", x, y, z),
}

Or:

let x = OverflowChecked<i32>(_x);
let y = OverflowChecked<i32>(_y);
match x + y {
  OverflowChecked::Overflow => println!("overflow!"),
  OverflowChecked::Value(z) => println!("{} + {} = {}", x, y, z),
}

I could write this manually since Rust guarantees wrapping semantics, but I was just checking that there isn't some standard way to do this.

Answer 1

The functions are named checked_[operator]. See checked_add for example:

fn main() {
    let x: u8 = 255;
    let y: u8 = 1;
    let z = x.checked_add(y);

    assert_eq!(z, None);
}