How should you do pointer arithmetic in Rust?

Question

I know the answer is \"you shouldn\'t\"... but for the sake of argument, how should you do it?

For example, if you wanted to write an alternative to Vec&l

Answer 1

Pointers have an offset method for pointer arithmetic.

fn main() {
    let items = [1usize, 2, 3, 4];

    let ptr = &items[1] as *const usize;

    println!("{}", unsafe { *ptr });
    println!("{}", unsafe { *ptr.offset(-1) });
    println!("{}", unsafe { *ptr.offset(1) });
}

Output

2
1
3

https://doc.rust-lang.org/nightly/book/first-edition/unsafe.html