[Measter]

I think Steve might have forgotten (so many helper functions...), but Rust's slices have a `copy_within`[1] function for exactly this scenario:

    fn main() {
        let mut buf: [u8; 16] = *b"D04GOKUD09OVER90";
        
        buf.copy_within(7..16, 0);
        
        println!("{:?}", buf);
    }

It does only support types that are trivially copyable, but it's implemented exactly you'd expect: bounds checking then memcopy handling overlap.

[1] https://doc.rust-lang.org/std/primitive.slice.html#method.co...

[steveklabnik]

I did! Wow! Thanks :)