Use explicitly-sized integers in the `product` method doc
@@ -685,7 +685,7 @@ pub trait ParallelIterator: Sized + Send {
/// ```
/// use rayon::prelude::*;
///
- /// fn factorial(n: usize) -> usize {
+ /// fn factorial(n: u32) -> u32 {
/// (1..n+1).into_par_iter().product()
/// }
///
