Function connect 

pub fn connect(
    resolver: &dyn Resolve,
    host: &str,
    port: u16,
    addresses: &CompiledPolicy<'_>,
    loopback_ok: &[SocketAddr],
    timeout: Duration,
) -> Result<TcpStream, Refusal>

Resolve host, refuse if any address is forbidden or matched by a deny rule of addresses (compiled from decide::address_policy), then connect to the first address that answers. A private address passes only when addresses names it. loopback_ok lists loopback addresses that may be reached anyway (tests); nothing exempts link-local or metadata.