It’s because Timestamp implements the FromStr trait which is one of the first traits everyone learns about when learning rust. So when you say that your value i

It’s because Timestamp implements the FromStr trait which is one of the first traits everyone learns about when learning rust. So when you say that your value is a Timestamp and the expression is string.parse()?, the compiler knows that it has to use the implementation which returns a Timestamp. There will never be two libraries that clash because of Rust’s orphan rule: you can only implement either a trait which you define on any type, or define a foreign trait on a type which you define, so there’s no way for some random library to also ship an implementation of FromStr for Timestamp