Function array_insert 

pub unsafe fn array_insert<T, const N: usize>(
    array: &mut [MaybeUninit<T>; N],
    i: usize,
    len: usize,
    elt: T,
)

Insert an element into the array.

Safety

• array[..len] is initialized,
• array[len..] is uninitialized,
• len < N, and
• i <= len.