#![allow(dead_code, deprecated, unused_variables, unused_mut)]
fn main() {
    let a = [0, 1, 2, -3, 4, 5, -6];
    let iter = a.into_iter().map_while(|x| u32::try_from(x).ok());
    let vec: Vec<_> = iter.collect();
    assert_eq!(vec, [0, 1, 2]);
}