Change Instant in Mutex

I want to print progress info in regular intervals while a rayon iterator runs. This is what I have so far:

let counter = AtomicU32::new(1);
let total = downloads.len();
let mut last_print = Mutex::new(Instant::now());

downloads.into_par_iter().map(|download: String| {
	let download_no = counter.fetch_add(1, Ordering::SeqCst);
		let lp = last_print.lock().unwrap();
		if lp.elapsed() > Duration::from_secs(5) {
			eprintln!("currently at download {} of {}", download_no, total);

	// do the download


So, 5 seconds after the start this will print for every download. I need to update last_print to the current time to prevent that. How can I do that?

You declare your mutex guard as mutable and dereference it:

let mut lp = last_print.lock().unwrap();
*lp = Instant::now();

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