Function bind_host_port 

pub fn bind_host_port<P>(
    factory: &dyn Factory,
    parent: Arc<Env>,
    binding: Symbol,
    port: Arc<P>,
) -> Result<Env>
where
    P: HostPort + 'static,

Creates a child environment and binds an opaque domain port in its local frame.

No process-global registry is involved; dropping the environment drops its ownership of the binding.