Initialize array holding struct more efficiently

Question

I have the following code:

const N: usize = 10000;
const S: usize = 7000;

#[derive(Copy, Clone, Debug)]
struct T {
    a: f64,
    b: f64,
    f: f64
}

fn main         


        

Answer 1

You can use std::mem::uninitialized(). Note, however, that it is considered unsafe and needs to be marked as such:

let mut t: [T; N] = unsafe { std::mem::uninitialized() };

As stated by the aforelinked docs:

This is useful for FFI functions and initializing arrays sometimes, but should generally be avoided.