Newtype for Autonomous System Number (ASN)
use Asn;
let asn = new;
assert_eq!;
let asn = from_str.expect;
assert_eq!;
Newtype for Autonomous System Number (ASN)
use asn::Asn;
let asn = Asn::new(0);
assert_eq!(asn, Asn::ZERO);
let asn = Asn::from_str("4294967295").expect("valid const last 32-bit ASN");
assert_eq!(asn, Asn::LAST4);