Fix borrow_multiply (thanks
///
/// type M = Array2<f32>;
///
-/// // Since this function borrows its inputs, captures must use ref
+/// // Since this function borrows its inputs, captures must use the x (x) pattern
/// fn borrow_multiply(a: &mut M, b: &M, c: &M) {
-/// azip!(mut a (a), ref b, ref c in { *a = b * c });
+/// azip!(mut a (a), b (b), c (c) in { *a = b * c });
/// }
///
/// fn main() {
///
/// assert_eq!(a, &b - &c);
///
+/// // Example of azip!() on borrowed values
+///
/// borrow_multiply(&mut a, &b, &c);
///
/// assert_eq!(a, &b * &c);
