const N: usize = 5;
struct MyStruct(usize);

fn main() {
    // Having it un-initialized doesn't work...
    let data: [MyStruct; N];
    // but also can't initialize it as it doesn't implement `Copy`
    // let data: [MyStruct; N] = [MyStruct(0); N];

    for i in 0..N {
        data[i] = MyStruct(i);
    }

    // Do other stuff with `data`...
}