}
}
-// ## Traits and borrowed types
+// ## Traits and reference types
//@ If you inspect the addition function above closely, you will notice that it actually consumes ownership of both operands
//@ to produce the result. This is, of course, in general not what we want. We'd rather like to be able to add two `&BigInt`.
// Writing this out becomes a bit tedious, because trait implementations (unlike functions) require full explicit annotation
// of lifetimes. Make sure you understand exactly what the following definition says. Notice that we can implement a trait for
-// a borrowed type!
+// a reference type!
impl<'a, 'b> ops::Add<&'a BigInt> for &'b BigInt {
type Output = BigInt;
fn add(self, rhs: &'a BigInt) -> Self::Output {