fn parenthesised_ip(rest: &str) -> Option<IpAddr>Expand description
The address in parentheses without brackets, right after the first word, as Microsoft 365 and Exchange write it (“from mail.sender.example (203.0.113.25) by …”, “(2001:db8::25)”), and qmail (“from unknown (HELO mail.sender.example) (203.0.113.5) by …”; “(ident@203.0.113.5)”, where what comes before the last “@” is what the sender’s ident service said). The group holds the address alone, a HELO group before it passed: a group holding anything else is not read.