It's not clear from context in your comment if you're saying this, but, for `x: &'a T`, 'a is a bound in two ways: - it is the maximum possible lifetime of the

It's not clear from context in your comment if you're saying this, but, for `x: &'a T`, 'a is a bound in two ways: - it is the maximum possible lifetime of the x variable itself, - it is the minimum lifetime of the `T` instance x points to. These are 100% related of course (x can't point to something that is invalid), but it is worth being careful about which end of a reference/pointer you're talking about when talking about validity.