> So, because libstd (well, Rust itself, but you get the idea) all three of FromStr, &str, and SocketAddr, it's allowed to do this. You, in your own package, c

> So, because libstd (well, Rust itself, but you get the idea) all three of FromStr, &str, and SocketAddr, it's allowed to do this. You, in your own package, could not define this, since you wouldn't have defined any of them. It's unclear to me what you're saying here. It's true that you can't make an inherent method `parse` on str like the one being called here, it's also true that one couldn't implement FromStr for SocketAddr in an external package, but one can create a custom generic function that uses FromStr and have that generic type be SocketAddr for some call sites. Of course, if this function wanted to have the syntax of a method call on str, it would have to be defined in a trait that users then import. > In tokio-core, they bring SocketAddr into scope: https://docs.rs/tokio-core/0.1.3/src/tokio_core/net/tcp.rs.h.. https://docs.rs/tokio-core/0.1.3/src/tokio_core/net/tcp.rs.h.... To be clear, this isn't necessary for calling methods---including inherent methods on SocketAddr---unlike the methods in a trait. The only reason to do this is that it lets one abbreviate the name: "SocketAddr" instead of "::std::net::SocketAddr".