URI: how to distinguish from invalid port vs no port number

[niklasad1]

Hey,

I read that default port was rejected in https://github.com/hyperium/http/issues/11.

However, the current API has pub fn port(&self) -> Option<Port<&str>> but it's not possible to distinguish when invalid port number vs when no port number. . Example:

let uri: Uri = "/hello/world".parse().unwrap();
assert!(uri.port().is_none());

let uri: Uri = "/hello/world:-9933".parse().unwrap();
assert!(uri.port().is_none());

Opinions about having pub fn port(&self) -> Result<Option<Port<&str>, Error> or something similar?