#![allow(dead_code, deprecated, unused_variables, unused_mut)]
#![feature(maybe_uninit_fill)]
use std::mem::MaybeUninit;
fn main() {
    let mut buf = [const { MaybeUninit::uninit() }; 3];
    let mut iter = [1, 2, 3, 4, 5].into_iter();
    let (initialized, remainder) = buf.write_iter(iter.by_ref());
    assert_eq!(initialized, & mut [1, 2, 3]);
    assert_eq!(remainder.len(), 0);
    assert_eq!(iter.as_slice(), & [4, 5]);
}